US20010032800A1

US20010032800A1 - Method of manufacturing semiconductor device and tray used in the method

Info

Publication number: US20010032800A1
Application number: US09/836,412
Authority: US
Inventors: Masato Numazaki; Usuke Enomoto; Hiromichi Suzuki; Hitoshi Kazama
Original assignee: Hitachi Ltd; Hitachi ULSI Systems Co Ltd
Current assignee: Hitachi Ltd; Hitachi Solutions Technology Ltd
Priority date: 2000-04-20
Filing date: 2001-04-18
Publication date: 2001-10-25
Also published as: KR20010098728A; JP2002002871A; TW523856B

Abstract

A tray is constituted by a tray body portion for connecting a plurality of pockets and cushioning portions which are arranged on the bottom portions of the pockets serving as contact positions between the pockets and CSPs when the CSPs are stored in the pockets and which are formed of a soft material having a degree of hardness lower than that of the tray body portion. The tray moderates impact force acting on the CSPs in falling the tray to prevent the CSP from being broken and damaged.

Description

FIELD OF THE INVENTION

The present invention relates to a semiconductor manufacturing technique and, more particularly, to a technique that is effectively applied to improve the protecting properties of a semiconductor device when semiconductor devices are stored by a built-up type tray.

BACKGROUND OF THE INVENTION

A plate-like vessel called a tray is known as a vessel, for storing semiconductor devices, used when semiconductor device (also called semiconductor packages) are transported between processes of semiconductor manufacturing processes or shipped.

A plurality of recessed pockets (storage portions) for storing semiconductor devices are formed in the tray to be aligned in the form of a matrix. The respective semiconductor devices are stored in the pockets. When the tray is built up on another tray, a plurality of semiconductor devices can be stored.

Of the semiconductor devices, as a semiconductor device in which a plurality of ball electrodes serving as external terminals are arranged (area array arrangement) in the form of a matrix on an external terminal fitting surface (surface on a mounting side) which is a rear surface of a main body formed by molding, a CSP (Chip Scale Package or Chip Size Package), a BGA (Ball Grid Array), or a wafer process package (to be referred to as a WPP hereinafter, a semiconductor package having a chip size and obtained such that pads on a wafer are rearranged in the form of an area array, molded, and then diced), or a flip-chip product is known. When the semiconductor device is stored and transported, a built-up type tray may be used.

In addition, the built-up type tray is not only used in transportation of a semiconductor device, but also may be used as a jig used in the following case. That is, a tray in which a semiconductor device is stored is turned over, the semiconductor device is supported by a tray arranged on the lower side, and the tray arranged on the upper side is removed to perform visual inspection for ball electrodes on the rear surface of a CSP or a BGA.

The built-up type tray may also be used as a jig used when a baking process for semiconductor devices is performed together with the trays.

The technique of a built-up type tray in which an electronic part or a micropatterned part such as a semiconductor device is stored is described in, e.g., Japanese Patent Application Laid-Open No. 11-208764, Japanese Patent Application Laid-Open No. 11-145315, or Japanese Patent Application Laid-Open No. 7-277389.

However, in a tray using the above technique, when the tray is impacted by falling during transportation of a semiconductor device, the semiconductor device in the tray is also impacted in a pocket. As a result, when the semiconductor device is a CSP, a WPP, or a flip-chip product of a chip-exposed type, a semiconductor chip may be cracked or split, so that the semiconductor chip is disadvantageously broken.

In addition, in a semiconductor device such as a BGA of a mold type which is relatively heavy, ball electrodes serving as external terminals of the BGA are disadvantageously transformed by impact caused by falling a tray, or the ball electrodes are disadvantageously cut out.

SUMMARY OF THE INVENTION

Therefore, an entire tray may be formed of a relatively soft material having a low degree of hardness. However, since the basic structure of the tray is a monolithic structure, the tray is bent by a baking process (e.g., a high temperature of 150° C. or higher). As a result, a tray cannot be removed when trays are built up. In this manner, a handling failure is disadvantageously caused.

Therefore, a technique in which a part of a tray is formed of a material different from the material of the tray body may be considered. However, such a technique is not described in Japanese Patent Application Laid-Open No. 11-208764, Japanese Patent Application Laid-Open No. 11-145315, or Japanese Patent Application Laid-Open No. 7-277389.

It is an object of the present invention to provide a method of manufacturing a semiconductor device which improves the protecting properties of the semiconductor device to prevent a semiconductor chip from being broken down and a tray used in this method.

Furthermore, it is another object of the present invention to provide a method of manufacturing a semiconductor device which reduces transformation of a tray and a tray used in this method.

According to one aspect of the present invention, a plurality of trays each having a tray body portion for connecting a plurality of storage portions and cushioning portions formed of a material softer than the tray body portion are prepared, a tray in which semiconductor devices are supported by the cushioning portions on the storage portions and another tray which can be built up on the tray are built up, and the cushioning portions of the tray and the other tray are arranged on both of front and rear surface sides of the semiconductor devices to store the semiconductor devices.

The outline of another aspect of this application will be described below in a plurality of items. More specifically,

1. a method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged on bottom portions which are contact positions between the storage portions and the semiconductor devices and formed of a material softer than the tray body portion;

the step of arranging the semiconductor devices in the storage portions of the trays to support surfaces of the semiconductor devices on a mounting side of the body portion with the cushioning portions; and

the step of building up the tray and another tray which can be built up on the tray and arranging the cushioning portions of the tray and the other tray on both of front and rear surface sides of the semiconductor devices in the storage portions of the tray to store the semiconductor devices.

2. A method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged on bottom portions and inner walls which are contact positions between the storage portions and the semiconductor devices and formed of a material softer than the tray body portion;

the step of arranging the semiconductor devices in the storage portions of the tray and supporting surfaces or external terminals of the semiconductor devices on a mounting side of the body portion with the cushioning portions; and

3. A method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged at contact positions between the storage portions and the semiconductor devices and formed of a resin material having a degree of hardness lower than that of the tray body portion;

the step of arranging the semiconductor devices in the storage portions of the tray and supporting the semiconductor devices with the cushioning portions; and

4. A method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged at contact positions between the storage portions and the semiconductor devices and formed of a material softer than the tray body portion;

5. A method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged to position the semiconductor devices in the storage portions and formed of a material softer than the tray body portion;

the step of arranging the cushioning portions inside gull-wing outer leads of the semiconductor devices and of positioning the semiconductor devices with the cushioning portions to store the semiconductor devices in the storage portions of the tray; and

the step of building up the tray and another tray which can be built up on the tray and of storing the semiconductor devices in the storage portions of the respective trays.

6. A method of manufacturing a semiconductor device is characterized by comprising:

the step of preparing a plurality of trays in which a plurality of storage portions have side walls and bottom surfaces connected to the side walls and the bottom surfaces are cushioning portions formed of a material softer than a tray body portion; and

the step of building up a first tray of the plurality of trays and a second tray of the plurality of trays and of storing the semiconductor devices such that the cushioning portions of the first tray and the second tray are arranged on both front and rear surface sides of the semiconductor devices in the storage portions of the first tray.

7. A tray comprises:

a tray body portion for connecting a plurality of storage portions in which semiconductor devices are stored; and

cushioning portions arranged in the storage portions and formed of a material softer than the tray body portion;

is characterized in that when the tray and another tray which can be built up on the tray while the semiconductor devices are stored in the storage portions of the tray, the cushioning portions are arranged on both front and rear surface sides of the semiconductor devices, and the cushioning portions on at least one of both the front and rear surface sides are in contact with the semiconductor devices.

The above objects, other objects, and novel characteristic features of the present invention will be apparent from the description of this specification and the accompanying drawings.

BRIEF DESCRIPTIONS OF THE DRAWINGS

FIGS. 1A to [0044] 1C are plan and side views showing an example of the structure of a tray on a front surface side used in a method of manufacturing a semiconductor device according to a first embodiment of the present invention, wherein FIG. 1A is a plan view, FIG. 1B is a side view in a tray longitudinal direction, and FIG. 1C is a side view in a tray width direction.
FIGS. 2A to [0045] 2C are enlarged views showing the detailed structure of portion A shown in FIG. 1A, wherein FIG. 2A is a plan view, FIG. 2B is a sectional view showing a B-B section in FIG. 2A, and FIG. 2C is a sectional view showing a C-C section in FIG. 2A.
FIG. 3 is a bottom view showing the structure of the tray on a rear surface side shown in FIG. 1. [0046]
FIG. 4 is an enlarged partial plan view showing the detailed structure of portion D shown in FIG. 3. [0047]
FIG. 5 is a graph of characteristic data showing an example of the characteristics of a material used for forming a tray body portion in the tray shown in FIG. 1. [0048]
FIG. 6 is a graph of characteristic data showing an example of the characteristics of a material used for forming a cushioning portion in the tray shown in FIG. 1. [0049]
FIG. 7 is an enlarged partial sectional view showing an example of a storage state of a semiconductor device using the tray shown in FIG. 1. [0050]
FIG. 8 is a perspective view showing an example of a state of a tray in transportation between steps in a method of manufacturing a semiconductor device using the tray shown in FIG. 1. [0051]
FIG. 9 is an enlarged partial sectional view showing an example of a state of a tray in inspection for the rear surface of a semiconductor device in a method of manufacturing a semiconductor device using the tray shown in FIG. 1. [0052]
FIG. 10 includes a packing process flow chart showing an example of a method of packing a semiconductor device in the method of manufacturing a semiconductor device using the tray shown in FIG. 1 and a perspective view corresponding to the packing procedures. [0053]
FIG. 11 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0054]
FIG. 12 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0055]
FIG. 13 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0056]
FIG. 14 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0057]
FIG. 15 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0058]
FIG. 16 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0059]
FIG. 17 is an enlarged partial sectional view showing a storage state of a semiconductor device when a tray of a modification is used in the method of manufacturing a semiconductor device according to the present invention. [0060]
FIGS. 18A to [0061] 18C are plan and side views showing the structure of the front surface side of a tray of a modification used in the method of manufacturing a semiconductor device according to the present invention, wherein
FIG. 18A is a plan view, [0062]
FIG. 18B is a side view in a tray longitudinal direction, and [0063]
FIG. 18C is a side view in a tray width direction. [0064]
FIG. 19 is a bottom view showing the structure of the rear surface side of the tray shown in FIG. 18. [0065]
FIG. 20 is an enlarged partial sectional view showing a cut structure of a storage portion in a longitudinal direction when a semiconductor device is stored in the tray shown in FIG. 18. [0066]
FIG. 21 is an enlarged partial sectional view showing a cut structure of a storage portion in a width direction when a semiconductor device is stored in the tray shown in FIG. 18. [0067]
FIG. 22 is an enlarged partial sectional view showing a storage state of a semiconductor device in a tray of a modification used in the method of manufacturing a semiconductor device according to the present invention. [0068]
FIG. 23 is an enlarged partial plan view showing an example of the structure of a tray according to a fourth embodiment of the present invention. [0069]
FIG. 24 is a partial sectional view showing a structure obtained when trays shown in FIG. 23 are built up while the structure is cut along an E-E line in FIG. 23.[0070]

DESCRIPTION OF THE PREFERRED EMBODIMENTS

Embodiments of the present invention will be described below with reference to the drawings. [0071]
In the following embodiments, the descriptions of the same parts or similar parts are not basically repeated except when the descriptions are required. [0072]
In addition, in the following embodiments, if necessary for convenience, the present invention is described in a plurality of sections or embodiments. However, except when a specific designation is made, these sections or embodiments are not unrelated to each other, one is the modification, detailed description, or supplementary description of a part or the whole of the other. [0073]
In the following embodiments, when the number of elements or the like (including the number of elements, numeral values, quantities, ranges, and the like) is mentioned, except when a specific designation is made and when the number of elements is rationally apparently limited to a specific number, and the number of elements may be equal to, larger than, or smaller than the specific number. [0074]
The same reference numerals denote the same parts in all the drawings for explaining the embodiments, and a repetitive description will be omitted. [0075]
A first embodiment of the present invention will be described below. [0076]
A [0077] tray 1 used in a method of manufacturing a semiconductor device (semiconductor package) according to the first embodiment is a built-up type plate-like tray in which the semiconductor devices are arranged in the form of a matrix. Here, as shown in FIG. 1, the tray 1 in which 12×17=204 semiconductor devices can be stored will be described below. However, the number of semiconductor devices which can be stored is not limited to 204, and the number of semiconductor devices may be 204 or less or may be 204 or more.
The semiconductor device stored in the [0078] tray 1 described in the first embodiment, as shown in FIG. 7, is obtained such that a plurality of ball electrodes (external terminals) 2 b are arranged in the form of an area array on an external terminal fitting surface (surface on a mounting side) 2 c which is a rear surface opposing the front surface side of a body portion 2 a of the tray 1. As an example, a small CSP 2 will be described below.
The [0079] tray 1 shown in FIGS. 1 to 4 will be described first. The tray is a built-up type tray which stores CSPs 2 and has a plurality of pockets (storage portions) 1 a arranged in the form of a matrix on both the front and rear surfaces. The tray 1 stores CSPs 2 in the pockets 1 a, and is used when desired processes such as preservation, transportation, characteristic selection, inspection, a baking process, and a shipping process are performed.
The configuration of the [0080] tray 1 is constituted by a tray body portion 1 d for connecting a plurality of pockets 1 a and cushioning portions 1 g arranged at contact positions between the pockets 1 a and the CSPs 2, the cushioning portions 1 g being formed of a material softer than the tray body portion 1 d.
More specifically, in the [0081] tray 1, the cushioning portion 1 g formed of a material softer than the tray body portion 1 d is arranged at a position where the pocket 1 a is in contact with the CSP 2 to moderate an impact force acting on the CSP 2 when the tray falls, so that the CSP 2 is prevented from being broken or damaged.
The pockets [0082] 1 a of the tray 1, as shown in FIG. 1 and FIG. 3, are formed at the same positions of both of a front surface 1 e (one surface) of the tray body portion 1 d and a rear surface 1 f (other surface) opposing the front surface 1 e. More specifically, the rear surface side of the pocket 1 a of the front surface 1 e is the pocket 1 a of the rear surface 1 f, and the pockets 1 a are formed on the front surface 1 e side and the rear surface 1 f side to sandwich the cushioning portions 1 g.
In the first embodiment, as shown in FIGS. 2A, 2B and [0083] 2C, the cushioning portion 1 g is arranged on a bottom portion 1 c of the pocket 1 a, and a plurality of projections 1 b are formed on both the front and rear surfaces of the cushioning portion 1 g.
In this case, as shown in FIG. 7, in the pocket [0084] 1 a on the front surface 1 e side, when the CSP 2 is stored in the pocket 1 a, the projections 1 b are formed on the cushioning portion 1 g so as not to be in contact with the ball electrodes 2 b of the external terminal fitting surface 2 c of a tape substrate 2 d of the body portion 2 a of the CSP 2.
More specifically, to the external [0085] terminal fitting surface 2 c of the tape substrate 2 d, the five projections 1 b are formed respectively on each of both the end portions of the bottom portion 1 c of the pockets 1 a in the longitudinal direction as shown in FIG. 2A such that the projections 1 b are in contact with the end portions of the external terminal fitting surface 2 c in the longitudinal direction to support the CSP 2.
On the other hand, in the pocket [0086] 1 a on the rear surface 1 f side, when built-up trays 1 having a large number of stages are turned over, as shown in FIG. 4, 18 projections 1 b are formed on the entire bottom portion 1 c of the pocket 1 a to be almost uniformly dispersed such that a surface 3 a (surface opposing a surface on which bonding electrodes are formed) of the semiconductor chip 3 in the CSP 2 stored in the pocket 1 a of the lower tray 1 which has not been turned over is supported after the trays are turned.
However, the number of [0087] projections 1 b formed on the front and rear surfaces of the cushioning portion 1 g is not limited to a specific number.
The [0088] projection 1 b has such a shape that a sectional area in the horizontal direction gradually decreases toward the distal end of the projection 1 b to make it possible to moderate impact force given to the CSP 2 when the tray 1 falls.
More specifically, the [0089] projections 1 b of the cushioning portion 1 g in the tray 1, as shown in FIGS. 2B and 2C, are formed to have conical shapes. However, the shape of the projection 1 b may be not only a conical shape but also a pyramidal shape, and may be a shape other than the conical shape and the pyramidal shape.
In manufacturing the [0090] tray 1, the tray body portion 1 d and the cushioning portion 1 g are manufactured by a double molding method which is a method which simultaneously performs molding operations by different molding materials.
Therefore, the [0091] tray body portion 1 d of the cushioning portion 1 g in the tray 1 preferably is formed of a resin material which can be easily subjected to transfer molding.
However, not using the double molding method, different molding operations may be performed for the [0092] tray body portion 1 d and the cushioning portion 1 g, respectively so as to join the tray body portion 1 d and the cushioning portion 1 g.
In the [0093] tray 1, the cushioning portion 1 g formed of a material softer than the tray body portion 1 d. For example, the degree of hardness of the resin material constituting the cushioning portion 1 g is preferably lower than the degree of hardness of the resin material constituting the tray body portion 1 d (preferably low).
In addition, since the [0094] tray 1 is also used as a storage jig when a baking process for the CSP 2 is performed, the tray body portion 1 d and the cushioning portion 1 g preferably formed of resin materials each having a high heat resistance. For example, the tray body portion 1 d and the cushioning portion 1 g more preferably are formed of resin materials each having a heat resistance of 150° C. or higher which is a temperature of the baking process.
Examples of the resin materials constituting the [0095] tray body portion 1 d and the cushioning portion 1 g are as follows. For example, the resin material of the tray body portion 1 d is polyphenylene ether (PPE), and the resin material of the cushioning portion 1 g formed of a material softer than the tray body portion 1 d is polyester-based elastomer. The main material characteristic data of both the materials are shown in FIG. 5 (PPE) and FIG. 6 (polyester-based elastomer), respectively.
The [0096] tray 1 is of a built-up type.
More specifically, as shown in FIG. 7, the [0097] trays 1 are formed to have such shapes that the trays 1 can be built up in a plurality of stages, and the CSPs 2 can be stored in the pockets 1 a of the trays 1 of the respective stages except for the uppermost stage. The pocket 1 a on the front surface 1 e side of the tray 1, as shown in FIG. 2A, is formed to be surrounded by cross-shaped front-surface-side guides 1 h at the corners (however, the pockets 1 a which are outermost arranged in the tray 1 are formed to be surrounded by cross-shaped and T-shaped front-surface-side guides 1 h or cross-shaped, T-shaped, and L-shaped front-surface-side guides 1 h).
Therefore, in order to obtain the built-up [0098] type trays 1, rear-surface-side guides 1 i as shown in FIG. 4 are arranged at positions corresponding to positions between the adjacent front-surface-side guides 1 h on the front surface 1 e side on the rear surface 1 f side. In this manner, when the trays 1 are built up, the trays 1 are fitted to each other without interfering the front-surface-side guides 1 h on the front surface 1 e side with the rear-surface-side guide 1 i on the rear surface 1 f side, so that the trays are positioned when the trays are built up.
The pocket [0099] 1 a on the front surface 1 e side is constituted by a region surrounded by cross-shaped, T-shaped, and L-shaped front-surface-side guides 1 h. When the CSP 2 is stored in the pocket 1 a on the front surface 1 e side, the four angle portions of the square body portion 2 a (which is the tape substrate 2 d in this case) of the CSP 2 are positioned by the respective inner walls 1 k of the cross-shaped, T-shaped, and L-shaped front-surface-side guides 1 h, so that the CSP 2 is positioned.
On the other hand, the pocket [0100] 1 a on the rear surface 1 f side, as shown in FIG. 4, is constituted by one pair of rear-surface-side guides 1 i and two pairs of rear-side-surface guides 1 i, i.e., 6 rear-surface-side guides 1 i arranged at positions of two pair of opposing sides of the square. When the CSP 2 is stored in the pocket 1 a on the rear surface 1 f side, the four sides of the square body portion 2 a (which is the tape substrate 2 d) of the CSP 2 are positioned by the respective inner walls 1 k of one pair of rear-surface-side guides 1 i and the two pairs of rear-surface-side guides 1 i which are arranged to be opposite to each other, so that the CSP 2 is positioned.
In addition, near the center of the [0101] tray 1 on the front surface 1 e side, as shown in FIG. 1A, adsorbing ribs 1 j for forming a closed region by connecting the cross-shaped front-surface-side guides 1 h are formed.
When trays are removed from the built-up [0102] trays 1 in order from the uppermost tray 1, the closed region closed by the cross-shaped front-surface-side guides 1 h and the adsorbing ribs 1 j is formed to prevent vacuum leakage caused when the closed region is vacuum-adsorbed.
The handling of the [0103] tray 1 is not limited to vacuum adsorption. Therefore, the absorbing ribs 1 j may not be always arranged.
Here, the structure of the [0104] CSP 2 stored in the tray 1 and shown in FIG. 7 will be described below. The semiconductor chip 3 is arranged on the square tape substrate 2 d having a size almost equal to that of the semiconductor chip 3, and the plurality of ball electrodes 2 b are arranged with an area array arrangement in an inner region (part) of the external terminal fitting surface 2 c opposing the chip arrangement side of the tape substrate 2 d. Therefore, the CSP 2 is of a Fan-In type.
Since the [0105] tape substrate 2 d is slightly larger than the semiconductor chip 3 in size, the body portion 2 a in the CSP 2 corresponds to the tape substrate 2 d.
A method of manufacturing a semiconductor device according to the first embodiment will be described below. [0106]
In the first embodiment, as the method of manufacturing a semiconductor device, desired processes such as preservation, transportation, characteristic selection, inspection (visual inspection), a baking process, and a shipping process of the [0107] CSP 2 using the tray 1 will be described below.
When the [0108] CSPs 2 are to be preserved by the tray 1, the plurality of built-up type trays 1 shown in FIGS. 1 to 4 are prepared. Each of trays 1 comprises the tray body portion 1 d in which the plurality of pockets 1 a arranged in the forms of matrixes are formed on both the front and rear surfaces; and the cushioning portions 1 g arranged at the bottom portions 1 c which are contact positions between the pockets 1 a and the CSPs 2, formed of a resin material softer than the tray body portion 1 d and having a degree of hardness higher than that of the tray body portion 1 d.
Subsequently, the [0109] CSP 2 is arranged in the pocket 1 a on the front surface 1 e side of the tray 1 (first tray), as shown in FIG. 7, so that the CSP 2 are supported by means of the projections 1 b of the cushioning portion 1 g by supporting the portions near both the ends of the external terminal fitting surface 2 c of the tape substrate 2 d which is the body portion 2 a.
In this manner, the [0110] CSP 2 is stored in the pocket 1 a.
In addition, on the [0111] tray 1, another tray 1 (second tray) which can be built up on the tray 1 is built up.
In this case, the rear-surface-side guides [0112] 1 i of the upper tray 1 are fitted in the front-surface-side guides 1 h of the lower tray 1 to build up the upper and lower trays.
In this manner, the [0113] CSP 2 can be stored in the pocket 1 a of the lower tray 1 such that the cushioning portions 1 g of the lower tray 1 and the upper tray 1 (another tray 1) are arranged on both the front and rear surface sides of the CSP 2.
When three or [0114] more trays 1 are built up, the CSP 2 is arranged in the pocket 1 a on the front surface 1 e side of the upper tray 1 (second) by the same method as described above, and a third tray 1 is built up on the resultant structure.
In this manner, as shown in FIG. 8, the [0115] trays 1 are built up in a plurality of stages to preserve the plurality of CSPs 2. However, since the upper most tray 1 is used as a lid, there is no CSPs 2 stored in the pockets 1 a of the uppermost tray 1.
In the built-up state shown in FIG. 8, the plurality of built-up [0116] trays 1 are bundled by a band 6. However, in order to only preserve the CSPs 2, bundling may not be always performed by the band 6.
Transportation, a baking process, and the like of the CSP [0117] 2 (semiconductor device) using the tray 1 will be described next.
For example, when the [0118] CSP 2 is transported by using the trays 1 between desired steps of the steps in manufacturing a semiconductor device, the CSPs 2 are stored in the pockets 1 a of the lowermost tray 1, the second tray 1, and the third tray 1 on the front surface 1 e side by the storing method described above. In addition, the plurality of trays 1 are built up in a plurality of stages. Since the uppermost tray 1 is used as a lid, the CSPs 2 are not stored in the uppermost tray 1.
Thereafter, the plurality of built-up [0119] trays 1 are bundled by the band 6 as shown in FIG. 8 to prevent the built-up trays 1 from being easily separated from each other.
In addition, the plurality of built-up [0120] trays 1 are transported between the semiconductor manufacturing steps by an automatic transportation vehicle or the like.
When the baking process of the [0121] CSPs 2 is performed, the plurality of built-up trays 1 in which the CSPs 2 are stored are passed through a baking furnace. In this manner, the plurality of CSPs 2 are subjected to the baking process together with the trays.
In this case, since the tray [0122] 1 (the tray body portion 1 d and the cushioning portion 1 g) according to the first embodiment formed of a resin material having high heat resistance, e.g., a resin material having a heat resistance of 150° C. which is a baking process temperature, the CSPs 2 can be subjected to the baking process together with the tray 1.
As the baking process, a baking process performed before packing as a moisture absorbing process for the [0123] CSPs 2 in the tray 1 in which the CSPs 2 are stored and a baking process performed after shipping (shipping destination) as a humidity absorbing process for the CSPs 2 which have been mounted on mounting boards are known.
A method of visually inspecting the [0124] ball electrodes 2 b of the CSPs 2 stored in the built-up trays 1 and a characteristic selecting method for the CSPs 2 will be described below.
For example, [0125] multi-stage trays 1 as shown in FIG. 8 obtained by staking the trays 1 in which the CSPs 2 are stored in the pockets 1 a on the front surface 1 e (one surface) side are prepared.
Subsequently, the built-up [0126] trays 1 are directly turned over, and the surfaces 3 a of the semiconductor chips 3 of the CSPs 2 are supported by the projections 1 b of the cushioning portions 1 g of the pockets 1 a on the rear surface 1 f (the other side) side of another tray 1 (another tray 1 arranged on the upper side before the turning over) arranged on the lower side by the turning over.
Thereafter, as shown in FIG. 9, the trays [0127] 1 (trays 1 arranged on the lower side before the turning over) arranged on the upper side by the turning over are sequentially removed to expose the CSPs 2 having the external terminal fitting surfaces 2 c facing upward. In this manner, visual inspection for the ball electrodes 2 b which are the external terminals of the CSPs 2 or electric characteristic selection inspection for the CSPs 2 is performed.
More specifically, even though the [0128] trays 1 are turned over in the built-up state, the CSPs 2 can be supported in a state in which the CSPs 2 are upside down. In this manner, when the trays 1 are used as jigs for supporting the CSPs 2, visual inspection for the ball electrodes 2 b arranged on the external terminal fitting surfaces 2 c of the body portions 2 a of the CSPs 2 and electric characteristic selection inspection for the CSPs 2 can be performed.
A packing and shipping method for the CSPs [0129] 2 (semiconductor devices) using the trays 1 will be described below.
As shown in step S[0130] 1 in FIG. 10, the plurality of built-up trays 1 in which the CSPs 2 are stored in the pockets 1 a shown in FIG. 7 are prepared.
More specifically, prepared are the built-up [0131] trays 1 in which the CSPs 2 are stored in the pockets 1 a of the trays 1 except for the uppermost tray 1.
Subsequently, as shown in step S[0132] 2, the built-up trays 1 are bundled by the band 6.
In this case, [0133] silica gel 7 serving as a humidity absorbing agent and an indicator card 8 for checking a humidity level are bundled by the band 6 together with the trays 1.
Thereafter, humidity-proof packing shown in step S[0134] 3 is performed.
Here, the built-up [0135] trays 1 bundled by the band 6 is put into a humidity-proof packing bag 9 formed of an aluminum-foil-contained film sheet, and the humidity-proof packing bag 9 is closed by heat sealing. A bar code label 11 in which the information of a product is described is stuck on a surface 9 a of the humidity-proof packing bag 9.
Thereafter, inner box packing shown in step S[0136] 4 is performed.
In this state, the humidity-[0137] proof packing bag 9 filled with the built-up trays 1 is put into an inner box (storage box) 4 together with an air cap 12 serving as a buffer material.
Subsequently, label display shown in step S[0138] 5 is performed.
More specifically, the [0139] bar code label 11 is stuck on the surface 4 a of the inner box 4.
Thereafter, outer box packing shown in step S[0140] 6 is performed.
Here, for example, a plurality of [0141] inner boxes 4 are filled in the outer box 5, and the outer box 5 is packed by taping. The bar code label 11 is stuck on a surface 5 a of the outer box 5.
In this manner, packing the [0142] trays 1 by using the humidity-proof packing bag 9, the inner box 4, and the outer box 5 is completed, and the outer box 5 is shipped.
In the method of manufacturing a semiconductor device according to the first embodiment, when the [0143] cushioning portions 1 g formed of a material softer than the tray body portions 1 d are arranged at the contact positions between the pockets 1 a of the trays 1 in which the CSPs 2 are stored and the CSPs 2, impact can be moderated by the cushioning portions 1 g even though the CSPs 2 are impacted by falling the trays 1 in transportation of the CSPs 2. Therefore, impact force acting on the semiconductor chips 3 can be reduced.
As a result, breakdown such as chip crack of the [0144] semiconductor chips 3 can be prevented. In this manner, the protecting properties of the CSPs 2 when the CSPs 2 are transported by the trays 1 can be improved.
Since impact can be moderated by the cushioning portion lg, impact force acting on the [0145] CSP 2 in impact can be reduced.
In this manner, the [0146] ball electrodes 2 b of the CSP 2 can be prevented from being transformed or damaged. As a result, as described above, the protecting properties of the CSP 2 in transportation or the like using the tray 1.
In addition, in the [0147] tray 1, the tray body portion 1 d and the cushioning portions 1 g in the pocket 1 a almost uniformly formed over the entire region of the tray body portion 1 d is not formed of one type of material (same material), but of different materials, respectively. For this reason, circulation of a molding material to the entire area of the tray body portion 1 d when the tray 1 is formed becomes uniform. As a result, transformation such as warpage of the tray 1 can be reduced.
In addition to this operation, when the [0148] tray body portion 1 d and the cushioning portion 1 g formed of resin materials each having heat resistance, transformation such as warpage of the tray 1 can be reduced even in a high-temperature atmosphere. Therefore, the tray 1 can be used in a baking process.
According to the first embodiment, in building up the [0149] trays 1, a cavity portion is formed on the front-surface side of the CSPs 2. For this reason, even though transformation such as warpage occurs in the tray 1, a partially concentrated load can be prevented from acting on the CSPs 2.
As a result, the [0150] CSPs 2 can be subjected to the baking process together with the tray 1 while the CSPs 2 are stored in the tray 1.
In addition, since transformation such as warpage of the [0151] tray 1 when the baking process is performed can be reduced, the invention is effective for recycling (reusing) of the tray 1.
In the [0152] tray 1 of the first embodiment, the cushioning portion 1 g in the pocket 1 a has a bottom surface connected to the inner wall 1 k serving as the side wall of the pocket 1 a. A CSP support portion including the bottom surface of the pocket 1 a is constituted only by the cushioning portion 1 g formed of a soft material.
In this manner, the CSP support portion of the pocket [0153] 1 a does not have a two-layered structure formed of a hard material constituting the tray body portion 1 d and a soft material constituting the cushioning portion 1 g, but has a structure formed of only a soft material. For this reason, the tray 1 can be easily manufactured, and the manufacturing cost of the tray 1 can be reduced.
In the [0154] tray 1 according to the first embodiment, when the CSPs 2 are stored in the pockets 1 a, and the trays 1 are built Up, a cavity portion is formed on the surface side of the CSP 2 (side opposing the ball electrodes 2 b).
In this manner, even though the [0155] trays 1 are warped, a concentrated load can be prevented from acting on the CSPs 2 in the pockets 1 a.
Furthermore, in the [0156] trays 1 according to the first embodiment, in building up the trays, only the cushioning portions 1 g of the upper and lower trays 1 are arranged on both the front and rear surfaces of the CSPs 2. For this reason, even though the CSPs 2 are brought into contact with the soft cushioning portions 1 g on the front-surface side due to warpage of the tray 1 or vibration in transportation of the trays, the CSPs 2 are not damaged, and the CSPs 2 can be prevented from being broken.
A second embodiment of the present invention will be described below. [0157]
FIGS. [0158] 11 to 17 are enlarged partial sectional views showing storage states of semiconductor devices when trays of modifications are used in the method of manufacturing a semiconductor device according to the present invention.
In the second embodiment, various modifications for the [0159] trays 1 used in the method of manufacturing a semiconductor device according to the first embodiment will be described below with respect to their structures and effects.
In a [0160] tray 1 shown in FIG. 11, in a cushioning portion 1 g arranged on a bottom portion 1 c of a pocket 1 a, a surface corresponding to the front surface 1 e of the pocket 1 a is formed as a flat surface 11, and a plurality of projections 1 b are separately formed on a surface corresponding to a rear surface 1 f.
More specifically, a surface which [0161] support ball electrodes 2 b of a CSP 2 in the cushioning portion 1 g is formed as the flat surface 11. In this manner, since a surface with which the ball electrodes 2 b of the CSP 2 are in contact is the flat surface 11, contacts between the ball electrodes 2 b and the cushioning portion 1 g are not related to the arrangement shape of the ball electrodes 2 b. Therefore, the CSP 2 in which the ball electrodes 2 b are formed in an area array arrangement over the entire area of an external terminal fitting surface 2 c of the CSPs 2 can be stored. As a result, it can effectively store the CSPs 2 or the like in which the ball electrodes 2 b are arranged in a full matrix.
In a [0162] tray 1 shown in FIG. 12, on both the surfaces of a cushioning portion 1 g formed on a bottom portion 1 c of a pocket 1 a, a plurality of projections 1 b are separately formed according to the fitting pitch and arrangement of the ball electrodes 2 b of the CSPs 2 such that the projections 1 b are not in contact with the ball electrodes 2 b.
More specifically, on both the surfaces of the [0163] cushioning portion 1 g, the plurality of projections 1 b are formed at such positions that the projections 1 b are not in contact with the ball electrodes 2 b of the CSP 2. In this manner, since the ball electrodes 2 b of the CSP 2 are positioned by the projections 1 b, the CSP 2 can be prevented from being unstable in a direction parallel to the cushioning portion 1 g in storing the CSP 2.
In this manner, damage of the [0164] semiconductor chip 3 of the CSP 2 caused by impact can be reduced.
In a [0165] tray 1 shown in FIG. 13, in contrast to the cushioning portion 1 g of the tray 1 shown in FIG. 11, a plurality of projections 1 b are separately formed on a surface corresponding to a front surface 1 e of the pockets 1 a in a cushioning portion 1 g, and a surface opposing the surface corresponding to the front surface 1 e is formed as a flat surface 11.
In this case, like the [0166] tray 1 shown in FIG. 12, the CSP 2 can be prevented from being unstable in a direction parallel to the cushioning portion 1 g in storing the CSP 2. Therefore, damage of the semiconductor chip 3 of the CSP 2 caused by impact can be reduced.
In a [0167] tray 1 shown in FIG. 14, the arrangement of a plurality of projections 1 b formed on a cushioning portion 1 g is made equal to the arrangement of the projections 1 b corresponding to the front surface 1 e side of the pocket 1 a of the cushioning portion 1 g of the tray 1 shown in FIG. 7 and described in the first embodiment.
More specifically, when the [0168] CSP 2 is stored in the pocket 1 a, the plurality of projections 1 b are formed on both the front and rear surfaces of the cushioning portion 1 g at such positions that the projections 1 b are reliably prevented from being in contact with the ball electrodes 2 b of the CSP 2. In this case, since the projections 1 b can be formed without being related to the set pitch and arrangement of the ball electrodes 2 b of the CSP 2, positions for forming the projections 1 b on the cushioning portion 1 g can be easily set.
In a [0169] tray 1 shown in FIG. 15, projections 1 b having the same arrangement as that of the projections 1 b shown in FIG. 14 are formed on only a side corresponding to the front surface le side of the pocket 1 a of the cushioning portion 1 g, and a surface opposing to the side is formed as a flat surface 11.
In this manner, the same effect as that of the [0170] tray 1 shown in FIG. 14 can be obtained.
In a [0171] tray 1 shown in FIG. 16, the front and rear surfaces of a cushioning portion 1 g are formed as flat surfaces 11. In this manner, the ball electrodes 2 b of a CSP 2 are directly supported by the flat surfaces 11 of the cushioning portion 1 g. For this reason, the conditions of contact positions between the ball electrodes 2 b of the CSP 2 and the cushioning portion lg are not related to the set pitch and arrangement of the ball electrodes 2 b. Therefore, as in the effect obtained by the tray 1 shown in FIG. 11, the tray 1 which is effective to store the CSPs 2 or the like having the ball electrodes 2 b arranged in a full matrix.
A [0172] tray 1 shown in FIG. 17, in addition to a cushioning portion 1 g of the bottom portion 1 c of the pocket 1 a, an inner surface 1 k of the pocket 1 a formed of the same material as that of the cushioning portion 1 g.
In this manner, in a semiconductor device such as the [0173] CSP 2 having the exposed semiconductor chip 3, impact generated when the side surface of the semiconductor chip 3 or an end portion of the tape substrate 2 d collides with the inner surface 1 k can be moderated. As a result, impact force acting on the semiconductor chip 3 can be further reduced.
Therefore, in addition to an impact force moderating effect obtained by the [0174] cushioning portion 1 g of the bottom portion 1 c of the pocket 1 a, the protecting properties of the CSP 2 can be improved.
The effects, i.e., a reduction in transformation such as warpage of the [0175] tray 1, being able to use the tray 1 in a baking process, and prevention of a concentrated load acting on the CSPs 2 by the cavity portion on the front-surface side of the CSPs 2 in building up the trays 1 can be obtained as in the first embodiment.
The resin materials constituting the [0176] tray body portions 1 d and the cushioning portions 1 g of the trays 1 shown in FIGS. 11 to 17, other structures of the trays 1, and the method of manufacturing a semiconductor device according to the second embodiment, i.e., preservation, transportation, characteristic selection, inspection (visual inspection), a baking process, and a shipping method of the CSPs 2 using the trays 1 shown in FIGS. 11 to 17 are the same as those described in the first embodiment. For this reason, a repetitive description thereof will be omitted.
A third embodiment of the present invention will be described below. [0177]
In the third embodiment, a semiconductor device stored in a [0178] tray 1 has a plurality of gull-wing outer leads (external terminals) 10 b as shown in FIG. 20, the outer leads 10 b are arranged at a small pitch (e.g., pitch of 0.4 mm to 0.5 mm), and each of the outer lead 10 b having a small lead thickness of about 0.1 mm. The tray 1 for storing the semiconductor device will be described below.
Therefore, in the third embodiment, as an example of the semiconductor device, a case in which a TQFP (Thin Quad Flat Package) [0179] 10 shown in FIG. 20 will be described. The semiconductor device may be an SOP (Small Outline Package) or the like except for the TQFP 10.
Each of [0180] trays 1 shown in FIGS. 18 and 19 is a built-up type tray in which the TQFP 10 shown in FIG. 20 can be stored. The tray 1 is constituted by a tray body portion 1 d having a plurality of pockets 1 a arranged in matrix arrangements on both the front and rear surfaces and for connecting the plurality of pockets 1 a; and rib-like cushioning portions 1 g arranged to position the TQFPs 10 in the pockets 1 a and formed of a material softer than the tray body portion 1 d. Each of the cushioning portions 1 g projects from a bottom portion 1 c like a rib.
More specifically, the rib-[0181] like cushioning portions 1 g projecting from the bottom portion 1 c, as shown in FIGS. 18A, 18B, 18C and 19, are formed along the four sides of square body portions 10 a serving as molding portions of the TQFPs 10 on the bottom portions 1 c of the pockets a to position the TQFPs 10 shown in FIG. 20, and the TQFPs 10 are positioned in the pockets 1 a by the rib-like cushioning portions 1 g. For this reason, the outer leads 10 b can be prevented from being in contact with inner walls 1 k of the pockets 1 a due to vibration or impact generated in transportation of the TQFPs 10 using the tray 1.
In a [0182] tray 1 shown in FIG. 22, as in the tray 1 described in the first embodiment, a cushioning portion 1 g is formed over the entire area of a bottom portion 1 c of the pocket 1 a together with cushioning portions 1 g projecting like ribs. As in the tray 1 shown in FIG. 18, the body portion 10 a of the TQFP 10 is positioned by the cushioning portions 1 g projecting like ribs.
When the [0183] TQFPs 10 are stored in the pockets 1 a of the trays 1 shown in FIGS. 18 and 22 according to the third embodiment, as shown in FIGS. 20, 21, and 22, the rib-like cushioning portions 1 g are arranged inside a gull-wing outer lead 10 b of the TQFP 10, and the body portion 10 a of the TQFP 10 is positioned and stored in the pocket 1 a by the rib-like cushioning portions 1 g.
When the [0184] tray 1 described in the third embodiment is used, the rib-like cushioning portions 1 g formed of a resin material softer than the tray body portion 1 d. For this reason, the cushioning portions 1 g can be prevented from being broken and lost by impact.
Therefore, when a semiconductor device such as the [0185] TQFP 10 which has the gull-wing outer leads 10 b, is of a narrow-pitch type, and has a small lead thickness of about 0.1 mm, the TQFP 10 can be reliably positioned in the pocket 1 a. For this reason, the outer lead 10 b can be prevented from colliding with the inner wall 1 k of the pocket 1 a. As a result, the outer leads 10 b in the TQFP 10 can be prevented from being transformed.
In addition, according to the third embodiment, in building up the [0186] trays 1, a cavity portion is formed on the front surface side of the TQFP 10 (semiconductor device). For this reason, even though transformation such as warpage occurs in the trays 1, a partially concentrated load can be prevented from acting on the TQFP 10 (semiconductor device).
The resin materials constituting the [0187] tray body portions 1 d and the cushioning portions 1 g in the trays 1 show in FIGS. 18 and 22, other structures of the trays 1, and the method of manufacturing a semiconductor device according to the third embodiment, i.e., preservation, transportation, characteristic selection, inspection (visual inspection), a baking process, and a shipping method of the TQFPs 10 using the trays 1 shown in FIGS. 18 to 22 are the same as those described in the first embodiment. For this reason, a repetitive description thereof will be omitted.
A fourth embodiment of the present invention will be described below. [0188]
In the fourth embodiment, a semiconductor stored in a [0189] tray 1 has a BGA board 13 a serving as a wiring board shown in FIG. 24, and a semiconductor chip 3 (see FIG. 7) is mounted on the wiring board. As an example of the semiconductor device, a BGA 13 will be described below, in which a plurality of ball electrodes 13 c are formed as external terminals in an area array arrangement on an external terminal fitting surface 13 b of a BGA board 13 a and which has a sealing body portion 13 d serving as a molding portion formed by sealing a semiconductor chip 3 with a resin mold.
However, as the semiconductor device, an LGA (Land Grid Array) except for the [0190] BGA 13 may be used, in which the semiconductor chip 3 is mounted on the wiring board.
Therefore, a [0191] tray 1 shown in FIG. 23 and used in a method of manufacturing a semiconductor device (semiconductor package) according to the fourth embodiment, like the tray 1 described in the first embodiment, is a built-up type plate-like tray in which the plurality of semiconductor devices are arranged in the form of a matrix. In FIG. 23, a partial structure (the pocket 1 a and the periphery thereof) on the front surface side of the tray 1 is enlargedly shown.
The characteristic parts of the [0192] tray 1 according to the fourth embodiment will be described below. The tray 1 has a tray body portion 1 d for connecting pockets 1 a which are a plurality of storage portions and cushioning portions 1 g arranged in the pockets 1 a and formed of a material softer than the tray body portion 1 d. When the tray 1 in which the BGA 13 is stored in the pocket 1 a and another tray 1 are built up, as shown in FIG. 24, the cushioning portions 1 g are arranged on both the front and rear surface sides of the BGA 13. The sealing body portion 13 d of the BGA 13 is supported by one (arranged on the front side of the BGA 13) of the cushioning portions 1 g, and the outer peripheral portion of the external terminal fitting surface 13 b of the BGA board 13 a is supported by the other cushioning portion 1 g (arranged on the rear side of the BGA 13).
In the [0193] tray 1 according to the fourth embodiment, the cushioning portions 1 g for supporting the lower (rear) side of the BGA 13 shown in FIG. 24 are formed at the four corners of each square pocket 1 a as shown in FIG. 23 to have L shapes. The L-shaped cushioning portions 1 g support the corners of the outer peripheral portion of the external terminal fitting surface 13 b of the BGA board 13 a of the BGA 13.
More specifically, when the [0194] BGA 13 is stored in the pocket 1 a, the L-shaped cushioning portions 1 g are arranged to support the outer region of a ball electrode arrangement region in the external terminal fitting surface 13 b of the BGA board 13 a such that the L-shaped cushioning portions 1 g are not in contact with the ball electrodes 13 c fitted on the BGA board 13 a.
Therefore, the [0195] cushioning portions 1 g for supporting the lower (rear) side of the BGA 13 (the external terminal fitting surface 13 b side of the BGA board 13 a) are not limited to the configuration in which the cushioning portions 1 g are arranged at four corners in the pockets 1 a. When the cushioning portions 1 g are arranged to support the outside region (outer peripheral portion) of the ball electrode arrangement region on the external terminal fitting surface 13 b of the BGA board 13 a, the cushioning portions 1 g may be arranged at positions except for the four corners in the pocket 1 a.
The L-shaped [0196] cushioning portions 1 g arranged at the four corners of each pocket 1 a may be integrated with the tray body portion 1 d and may be formed of the same hard material as that of the tray body portion 1 d. In this case, the L-shaped cushioning portions 1 g serve as package support portions formed of the same material as that of the tray body portion 1 d.
Therefore, when the [0197] trays 1 according to the fourth embodiment are built up such that the BGAs 13 are stored in the trays 1, of the cushioning portions 1 g arranged on both the front and rear surface sides of the BGAs 13, the cushioning portions 1 g arranged on at least the upper sides (front sides) of the BGAs 13 may be in contact with the sealing body portions 13 d serving as the molding portions of the BGAs 13 to support the sealing body portions 13 d. The cushioning portions 1 g for supporting the lower side (rear side) of the BGA board 13 a may be formed of a soft material softer than the tray body portion 1 d, and may be formed of the same hard material as that of the tray body portion 1 d.
However, both the [0198] cushioning portions 1 g preferably are formed of a soft material softer than the tray body portion 1 d.
Therefore, in the [0199] tray 1 according to the fourth embodiment, when both the cushioning portions 1 g arranged on both the front and rear surface sides of the BGA 13 are formed of a soft material softer than the tray body portion 1 d, at least the cushioning portions ig arranged on one of the front and rear surfaces of the BGA 13 may have a structure in which the cushioning portions ig are in contact with the BGA 13 to support the BGA 13.
Subsequently, the detailed structure of the [0200] tray 1 will be described below. In the tray body portion 1 d, the pocket 1 a which is surrounded by partition walls 1 s serving as side walls and a bottom plate 1 t and which is a storage portion formed as a recessed portion 1 s formed in a quadratic shape (square), and a leg portion 1 w as shown in FIG. 24 is downwardly formed on a side edge 1 u extending from the outer edge of the tray body portion 1 d.
In addition, connection holes [0201] 1 r the number of which is proper and which shown in FIG. 23 are formed in the bottom plate 1 t of the pocket 1 a, and rib-shaped cushioning portions 1 g are formed on the upper surface and the lower surface of the bottom plate 1 t of the pocket 1 a of the tray body portion 1 d.
The [0202] tray body portion 1 d is molded by using a synthetic resin such as polystyrene, polyethylene, polypropylene, or a vinyl chloride resin having thermoplasticity. However, it is recommended to obtain antistatic properties that electric conductivity and elasticity are given to the tray body portion 1 d by using conductive carbon, a conductive material such as graphite, rubber having elasticity, or a material to which an elastic material such as polybutadiene is added.
Amounts of additives of these compositions are adjusted to have, for example, a ratio of 70% of polystyrene, 10% of carbon, and 20% of polybutadiene. As a molding method, a method using injection molding is convenient. However, this method is not limited to the method using injection molding, as a matter of course. [0203]
The pocket [0204] 1 a serving as a storage portion is a position where a semiconductor device such as the BGA 13 is stored and it is formed in a recess shape by a bottom plate it and partition walls is. In this case, the horizontal area and height of the pocket 1 a are properly set by the size of the BGA 13 to be stored, or the pocket 1 a must have a flat surface and a height such that at least the BGA 13 is not in contact with the partition wall is and does not project from the partition walls is.
In addition, it is recommended that the partition walls is are formed in accordance with the external shape of the [0205] BGA 13.
In addition, a notch portion [0206] 1 v is formed in the partition wall 1 s between the adjacent pockets 1 a. The notch portion 1 v is formed by notching the partition wall 1 s to obtain a surface almost parallel to the bottom plate 1 t. The notch portion 1 v is used as a position where a connection portion 1 g for connecting an annular cushioning portion 1 g is formed. When the connection portion 1 g is not formed, the notch portion 1 v need not be formed in the partition wall 1 s.
The connection holes [0207] 1 r are holes which simultaneously mold ribs 1 m and holding portions 1 n or into which the holding portions 1 n are pressed when the annular cushioning portion 1 g is formed in the pocket 1 a. The plurality of connection holes 1 r the number of which is proper are formed at a position where the annular cushioning portion 1 g of the pocket 1 a is formed. In particular, the connection holes 1 r are desirably formed at at least four positions including a crossing position between the rib 1 m and the connection portion 1 g.
The [0208] annular cushioning portion 1 g comprises the rib 1 m projecting from the bottom plate 1 t of the pocket 1 a; the holding portion in which presses the BGA 13 from the upper side when the trays 1 are built up, a connection portion 1 p for connecting the rib 1 m and the holding portion 1 n to each other, and the cushioning portion 1 g for connecting adjacent ribs 1 m.
The [0209] rib 1 m is angularly formed on the bottom surface portion of the pocket 1 a, and the rib 1 m is connected to another adjacent rib 1 m by the connection portion 1 g. The holding portion 1 n is angularly formed on the lower surface (rear surface side) of the bottom plate 1 t of the pocket 1 a. The rib 1 m and the holding portion 1 n are connected to each other by the connection portion 1 p through the connection holes 1 r, the number of which is proper and which are formed in the bottom plate 1 t.
The set width and height of the [0210] rib 1 m are not limited to specific values. However, the width and height are adapted to the size of the BGA 13 to be stored, and the rim 1 m must have such a height that the rib 1 m is not in contact with the ball electrodes 13 c of the BGA 13 when the BGA 13 is mounted in the pocket 1 a.
On the other hand, the set width and height of the holding portion in are not limited to specific values. However, the width and height are adapted to the size of the [0211] BGA 13, and the holding portion in is in contact with the sealing body portion 13 d of the BGA 13 stored in the lower tray 1 when the trays 1 are built up. The height is desirably set to be such a height that a high pressure does not act on the sealing body portion 13 d.
In addition, the L-shaped and [0212] annular cushioning portions 1 g have flexibility to absorb impact to the tray 1 such that the impact is prevented from being transmitted to the BGA 13. As the material of the cushioning portions 1 g, a material (more specifically, a material having a heat distortion temperature of 150° C. or more is recommended) which has heat resistance and which is not transformed when the tray 1 is thermally washed is used, and, for example, polyester elastomer, a silicon resin, or polyurethane is used.
A method of forming the [0213] annular cushioning portion 1 g is as follows. That is, molds for molding the cushioning portions 1 g are fitted on the upper and lower surfaces of the tray 1, and a proper resin is injected into the molds by an injection molding method or the like. The injected resin forms the rib 1 m and the cushioning portion 1 g, and is injected into the connection holes 1 r. The resin is flowed from the connection holes 1 r to form the holding portion 1 n and the connection portion 1 p, thereby integrally molding the cushioning portion 1 g.
The method of molding the [0214] cushioning portion 1 g is not limited to the above method. The cushioning portion 1 g constituted by the rib 1 m, the holding portion 1 n, and the connection portion 1 p may be formed independently of the tray 1, and the cushioning portion 1 g may be inserted into the connection hole 1 r. Molds may be fitted on the upper and lower surfaces of the tray body portion 1 d without forming the connection holes 1 r and the connection portion 1 p, and the rib 1 m and the holding portion 1 n may be independently formed by injection molding.
Therefore, similarly, the L-shaped [0215] cushioning portions 1 g are formed independently of the tray body portion 1 d by injection molding.
The [0216] rib 1 m and the holding portion 1 n need not be angularly formed, and may be formed as dotted or linear projections each having a proper width. The rib 1 m and the holding portion 1 n may be flatly formed on the entire area of the bottom plate 1 t of the pockets 1 a or a part, e.g., four corners, of the bottom plate 1 t.
Therefore, when the [0217] rib 1 m and the holding portion in are formed like dots, the cushioning portions 1 g need not be formed. When the rib 1 m and the holding portion 1 n are formed like dots, lines, or planes, the connection holes 1 r and the connection portion 1 p need not be formed.
The [0218] rib 1 m and the holding portion 1 n may be formed by adhering a silicon resin, polyurethane, or a vinyl chloride resin which is formed into an annular shape or another shape, a foam plastic, or a sponge (the L-shaped cushioning portions 1 g at the four corners in the pocket 1 a are similarly formed).
The [0219] annular cushioning portion 1 g may be inserted and fitted in the connection hole 1 r by the following manner. That is, the connection hole 1 r is entirely or properly formed on the bottom plate it of the pockets 1 a, the cross section of the cushioning portion 1 g is made equal to the shape of the connection hole 1 r, and, on a longitudinal section, the rib 1 m and the holding portion 1 n are formed to project from the upper and lower surfaces of the bottom plate 1 t. In this case, the rib 1 m and the holding portion in projecting from the bottom plate it of the cushioning portion 1 g are formed like dots, lines, or planes to constitute the rib 1 m and the holding portion 1 n.
A side edge [0220] 1 u of the tray body portion 1 d extends on the outer edge of the tray body portion 1 d in the four directions to have a proper width, and a leg portion 1 w is downwardly formed on the side edge 1 u. The leg portion 1 w is placed on the side edge 1 u of the lower tray 1 when the trays 1 are built up. The leg portion 1 w is formed to be adapted to the sizes of the BGA 13, the rib 1 m, and the holding portion 1 n and to have such a proper height that an unnecessary pressure does not act on the BGA 13. The leg portion 1 w may be directly formed on the bottom plate 1 t without forming the side edge 1 u, and the leg portion 1 w may not be specially formed.
A using procedure of the [0221] tray 1 according to the fourth embodiment will be described below. The BGA 13 is placed in the pocket 1 a of the tray 1, and is supported by the L-shaped cushioning portions 1 g arranged at the four corners.
In this manner, the [0222] BGA 13 is supported by the L-shaped cushioning portions 1 g arranged at the four corners at which the outer peripheral portion of the external terminal fitting surface 13 b of the BGA board 13 a is arranged in the pocket 1 a.
In this manner, the [0223] trays 1 in which the BGAs 13 are built up such that the leg portions 1 w of the upper tray 1 are placed on the side edge 1 u of the lower tray 1. In this case, the holding portion in formed on the upper tray 1 holds the sealing body portion 13 d of the BGA 13 stored in the lower tray 1 from the upper side, and the BGA 13 is held by the cushioning portions 1 g from the upper and lower sides.
More specifically, in the [0224] BGA 13, the sealing body portion 13 d is supported by the holding portion in of the upper tray 1 from the upper side, and the BGA board 13 a is supported by the L-shaped cushioning portions 1 g of the lower tray 1 from the lower side.
The [0225] trays 1 built up as described above are packed in a box, and the box is transported.
In order to examine an influence to the [0226] BGA 13, the tray 1 formed of a vinyl chloride resin in which the cushioning portions 1 g formed of polyester elastomer were arranged and the tray 1 in which the cushioning portions 1 g were not arranged were used, and the five trays 1 in which the BGAs 13 were stored were built up to be packed. Drop tests of the trays 1 were performed to a concrete floor every 5 cm. As a result, the BGAs 13 stored in the tray 1 in which the cushioning portions 1 g were not arranged were damaged in the drop test at a height of 10 cm. However, the BGAs 13 stored in the tray 1 in which the cushioning portions 1 g were arranged were not damaged in the drop test at a height of 60 cm.
As described above, in the fourth embodiment, when the holding portion [0227] 1 n constituting the cushioning portion 1 g is arranged on the lower surface of the bottom plate 1 t of each pocket 1 a of the tray 1 is arranged, the BGA 13 is prevented by friction between the BGA 13 and the holding portion in from being easily slipped in comparison with a case in which the BGA 13 is stored in the pocket 1 a of the tray 1 having a low coefficient of friction. The BGA 13 can be prevented in the pocket 1 a from horizontally moving (horizontal slipping).
As a result, the [0228] BGA 13 can be prevented from being damaged by being in contact with the partition wall is serving as a side wall, and impact from the lower side of the tray 1 is absorbed by the cushioning portion 1 g, and is not transmitted to the BGA 13. For this reason, the BGA 13 can be prevented from being broken.
In addition, in the [0229] tray 1 according to the fourth embodiment, since the cushioning portions 1 g are formed on both the upper and lower surfaces of the bottom plate 1 t of each pocket 1 a, the BGA 13 can be held with proper pressures from the upper and lower sides when the trays 1 are built up. For this reason, the BGA 13 do not move in the pocket 1 a of the BGA 13, and impact to the tray 1 is absorbed by the cushioning portion 1 g and not transmitted to the BGA 13. Therefore, the BGA 13 can be reliably prevented from being broken.
Since the [0230] rib 1 m on the upper surface of the bottom plate 1 t of the pocket 1 a and the holding portion 1 n on the lower surface are connected to each other through the connection hole 1 r formed in the bottom plate 1 t of the pocket 1 a and integrally molded, the molding process of the cushioning portion 1 g can be simplified, and the cushioning portion 1 g can be formed to have a large thickness. For this reason, the cushioning portion 1 g can more absorb impact to the trays 1 and can prevent the impact from being transmitted to the BGA 13. Therefore, the BGA 13 can be prevented from being broken.
Furthermore, the L-shaped [0231] cushioning portions 1 g are arranged at the four corners on the upper surface of the bottom plate 1 t of each recessed pocket 1 a of the tray 1, and the holding portion 1 n constituting the cushioning portions 1 g is arranged on the lower surface of the bottom plate 1 t. In this manner, when the trays 1 in which the BGAs 13 are placed in the pockets 1 a and supported by the L-shaped cushioning portions 1 g are vertically built up supporting the BGA 13, the BGAs 13 can be held from the upper and lower sides by the L-shaped cushioning portions 1 g arranged on the upper surface of the bottom plates 1 t of the pockets 1 a and the holding portions 1 n serving as the cushioning portions 1 g arranged on the lower surface of the bottom plates 1 t of the pockets 1 a of the upper tray 1 for storing the BGAs 13.
Therefore, when the [0232] trays 1 in which the BGA 13 are stored are transported (conveyed), the BGAs 13 do not move in the pockets 1 a, and vibration in transportation is not easily transmitted to the BGAs 13. As a result, the BGAs 13 can be prevented from being broken.
The invention made by the present inventor has been described above on the basis of the embodiment of the invention. However, the present invention is not limited to the embodiments of the invention. Various changes and modifications of the invention can be effected without departing from the spirit and scope of the invention, as a matter of course. [0233]
For example, in the first embodiment described above, the case in which a semiconductor device (semiconductor package) is the [0234] CSP 2 is described. The semiconductor device is not limited to the CSP 2, and any semiconductor device in which the ball electrodes 2 b serving as external terminals are arranged on the external terminal fitting surface 2 c of the body portion 2 a may be used. A WPP, BGA, or a flip-chip product having wire bumps comprising Au may be used.
In the first to third embodiments described above, as the materials of the [0235] tray body portion 1 d and the cushioning portion 1 g constituting the tray 1, the material of the tray body portion 1 d is polyphenylene ether (PPE), and the material of the cushioning portion 1 g is polyester-based elastomer or the like. However, as the materials constituting the tray body portion 1 d and the cushioning portion 1 g, if the cushioning portion 1 g is formed of a molding material softer than the tray body portion 1 d, other molding materials except for the PPE and the polyester-based elastomer may be used.
In addition, in the drawings showing the built-up states of the [0236] trays 1 described in the first to fourth embodiments, the case in which the trays 1 are built up in two stages is illustrated. However, the number of built-up trays 1 is not limited to a specific value, and any number of built-up trays 1 may be used.

Claims

What is claimed is:

1. A method of manufacturing a semiconductor device with storing semiconductor devices in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform desired processes such as preservation, transportation, and inspection for the semiconductor devices, comprising:

the step of arranging the semiconductor devices in the storage portions of the trays to support the semiconductor devices with the cushioning portions; and

2. A method of manufacturing a semiconductor device with storing semiconductor devices in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform preservation, transportation, characteristic selection, inspection, a baking process, or shipping for the semiconductor devices, comprising:

the step of preparing the plurality of trays each having a tray body portion for connecting the plurality of storage portions; and cushioning portions arranged on bottom portions which are contact positions between the storage portions and the semiconductor devices and formed of a material softer than the tray body portion;

3. A method of manufacturing a semiconductor device with storing semiconductor devices in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform preservation, transportation, characteristic selection, inspection, a baking process, or shipping for the semiconductor devices, comprising:

the step of preparing the plurality of trays each having a tray body portion for connecting a plurality of storage portions; and cushioning portions arranged on bottom portions and inner walls which are contact positions between the storage portions and the semiconductor devices and formed of a material softer than the tray body portion;

4. A method of manufacturing a semiconductor device with storing semiconductor devices in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform preservation, transportation, characteristic selection, inspection, a baking process, or shipping for the semiconductor devices, comprising:

5. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray in which the tray body portion and the cushioning portions are formed of a resin material to which transfer molding can be easily performed.

6. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray is used in which the tray body portion and the cushioning portions are formed of a resin material having high heat conductivity.

7. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray is used in which a plurality of projections are formed on front and rear surfaces of the cushioning portions arranged on bottom portions of the storage portions.

8. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray is used in which a plurality of projections are formed at least one surface of front and rear surfaces of the cushioning portions arranged on bottom portions of the storage portions and the other surface is formed as a flat surface.

9. A method of manufacturing a semiconductor device according to

claim 7

, wherein the tray is used in which the projections of the cushioning portions are separately arranged on one or both of the front and rear surfaces of the cushioning portions.

10. A method of manufacturing a semiconductor device according to

claim 7

, wherein the tray is used in which the projections of the cushioning portions are arranged at positions which are not in contact with an external terminals of the semiconductor devices on one or both of the front and rear surfaces of the cushioning portions.

11. A method of manufacturing a semiconductor device according to

claim 7

, wherein the tray is used in which each of the projections of the cushioning portions is formed to have such a shape that a sectional area in the horizontal direction gradually decreases toward its distal end.

12. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray in which both the front and rear surfaces of the cushioning portions are formed as flat surfaces is used.

13. A method of manufacturing a semiconductor device according to

claim 1

, wherein the tray in which inner walls of the storage portions are formed of the same material as that of the cushioning portions is used.

14. A method of manufacturing a semiconductor device with storing semiconductor devices having ball electrodes as external terminals in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform preservation, transportation, characteristic selection, inspection, a baking process, or shipping for the semiconductor devices, comprising:

15. A method of manufacturing a semiconductor device according to

claim 14

, wherein the tray for storing the semiconductor devices in each of which the plurality of ball electrodes are fitted in an area array arrangement over an almost entire area of an external terminal fitting surface is used.

16. A method of manufacturing a semiconductor device according to

claim 14

, wherein the tray for storing the semiconductor devices in each of which the plurality of ball electrodes are fitted in an area array arrangement on a part of an external terminal fitting surface is used.

17. A method of manufacturing a semiconductor device according to

claim 14

, wherein the tray is used in which projections of the cushioning portions arranged on bottom portions of the storage portions are arranged at positions which are not in contact with the ball electrodes of the semiconductor devices on one or both of front and rear surfaces of the cushioning portions.

18. A method of manufacturing a semiconductor device according to

claim 15

19. A method of manufacturing a semiconductor device according to

claim 16

20. A method of manufacturing a semiconductor device according to

claim 1

, wherein the plurality of trays are built up in a plurality of stages, the plurality of semiconductor devices are arranged on the plurality of stages, and the plurality of built-up trays are conveyed between semiconductor manufacturing steps.

21. A method of manufacturing a semiconductor device according to

claim 1

, wherein the plurality of trays are built up in a plurality of stages, the plurality of semiconductor devices are arranged on the plurality of stages, and the plurality of built-up trays are stored in a storage box and shipped.

22. A method of manufacturing a semiconductor device according to

claim 1

, wherein the trays built up in a plurality of stages in which the semiconductor devices are stored in the storage portions of one of the front and rear surfaces are turned over; the semiconductor devices are supported by the cushioning portions of the storage portions on the other surface of the tray arranged on lower side by the turning-over, thereafter, the trays arranged on upper side by the turning over are sequentially removed to expose the semiconductor devices; and an external terminals of the semiconductor devices are visually inspected.

23. A method of manufacturing a semiconductor device according to

claim 1

, wherein the plurality of trays are built up in a plurality of stages; the plurality of semiconductor devices are stored on the plurality of stages; and the semiconductor devices stored in the plurality of built-up trays are subjected to a baking process together with the trays.

24. A method of manufacturing a semiconductor device with storing semiconductor devices having gull-wing outer leads as external terminals in storage portions of built-up type trays having a plurality of storage portions on both front and rear surfaces to perform preservation, transportation, characteristic selection, inspection, a baking process, or shipping for the semiconductor devices, comprising:

the step of arranging the cushioning portions inside the gull-wing outer leads of the semiconductor devices and of positioning the semiconductor devices with the cushioning portions to store the semiconductor devices in the storage portions of the tray; and

25. A method of manufacturing a semiconductor device according to

claim 24

, wherein the plurality of trays are built up in a plurality of stages; the plurality of semiconductor devices are arranged and stored on the plurality of stages; and the plurality of built-up trays are conveyed between semiconductor manufacturing steps.

26. A method of manufacturing a semiconductor device according to

claim 24

, wherein the plurality of trays are built up in a plurality of stages; the plurality of semiconductor devices are arranged and stored on the plurality of stages; and the plurality of built-up trays are stored in a storage box and shipped.

27. A method of manufacturing a semiconductor device according to

claim 24

, wherein the plurality of trays are built up in a plurality of stages; the plurality of semiconductor devices are stored on the plurality of stages, and the semiconductor devices arranged and stored in the plurality of built-up trays are subjected to a baking process together with the trays.

28. A method of manufacturing a semiconductor device with storing semiconductor devices in storage portions of built-up type trays having a plurality of storage portions and a tray body portion for connecting the storage portions to perform desired processes such as preservation, transportation, and inspection for the semiconductor devices, comprising:

the step of preparing a plurality of trays in which the plurality of storage portions have side walls and bottom surfaces connected to the side walls and the bottom surfaces are cushioning portions formed of a material softer than the tray body portion; and

29. A tray having a plurality of recessed storage portions, comprising:

wherein when the tray and another tray which can be built up on the tray while the semiconductor devices are stored in the storage portions of the tray, the cushioning portions are arranged on both front and rear surface sides of the semiconductor devices, and the cushioning portions on at least one of both the front and rear surface sides are in contact with the semiconductor devices.

30. A tray according to

claim 29

, wherein the semiconductor devices have sealing body portions in which semiconductor chips are mounted on wiring boards and which have sealing body portions for sealing the semiconductor chips, a plurality of external terminals are arranged in an area array arrangement on the wiring boards; and, when the tray in which the semiconductor devices are stored in the storage portions and the other tray are built up, of the cushioning portions arranged on both the front and rear surface sides of the semiconductor devices, the cushioning portions on at least one of both the front and rear surface sides are in contact with the sealing body portions of the semiconductor devices.

31. A tray according to

claim 29

, wherein the semiconductor devices have sealing body portions in which semiconductor chips are mounted on wiring boards and which have sealing body portions for sealing the semiconductor chips; a plurality of external terminals are arranged in an area array arrangement on the wiring boards; and, when the tray in which the semiconductor devices are stored in the storage portions and the other tray are built up, of the cushioning portions arranged on both the front and rear surface sides of the semiconductor devices, the cushioning portions on one of both the front and rear surface sides support the sealing body portions of the semiconductor device; and the cushioning portions on the other of both the front and rear surface sides support outer peripheral portions of external terminal fitting surfaces of the wiring boards.