WO2014090925A1

WO2014090925A1 - Gas mixing device

Info

Publication number: WO2014090925A1
Application number: PCT/EP2013/076329
Authority: WO
Inventors: Baskar Pagadala Gopi
Original assignee: Aixtron Se
Priority date: 2012-12-14
Filing date: 2013-12-12
Publication date: 2014-06-19
Also published as: TW201433355A; DE102013113817A1; WO2014090925A4

Abstract

The invention relates to a device for mixing a number of gases, said device comprising a plurality of gas feeds (3) that lead into a mixing chamber (1), a gas baffle device (4, 5, 18, 23, 24, 25) for generating a circulating gas flow and a gas outlet opening (6, 22) or a gas outlet pipe (2), into which the gas outlet opening (22) leads. The gas flows that are fed into the mixing chamber (1) via the gas feeds (3) flow out of said mixing chamber (1) by means of the outlet opening. In order to further develop the device for advantageous use, according to the invention the first gas baffle device (4, 5,18, 23, 24, 25) is located in the mixing chamber (1).

Description

Gas mixing device

The invention relates to a device for mixing together a plurality of gases, with a plurality of gas supply lines, which open into a mixing chamber, with a first Gasumlenkeinrichtung to produce a circulating gas stream and with a gas outlet opening or a gas outlet tube, in particular gas mixing tube, in which from the gas supply lines in the mixing chamber fed gas streams flow out of the mixing chamber. A gas mixing device shows the US 2009/0120364 AI. The gas mixing device serves to mix together different gases. The gases are introduced by means of gas supply lines in a premixing chamber, where a first mixing of the gases takes place. The gases are diverted and fed to a gas mixing tube. In order to improve the mixing, a Gasumlenkeinrichtung is provided which imposes a swirling the gas. The Gasumlenkeinrichtung is formed by an insert which is inserted into the gas mixing tube.

In CVD devices, a coating is applied to substrates. For this purpose, process gases are introduced through a gas inlet element into a process chamber where the substrates to be coated are located. In the process chamber, chemical reactions take place, resulting in reaction products that deposit on the surface of the substrates. If a homogeneous gas mixture is to be introduced into the process chamber, the process gases must first be mixed in suitable mixing devices. For example, US Pat. No. 7,540,305 B2 shows a CVD process chamber with a gas inlet organ designed as a shovelhead, in which different from one another Process gases are to be fed. For this purpose, a mixing device is provided in the upstream direction.

DE 10 2005 003 984 A1 describes an annular ring surrounding the periphery of a showerhead, in which process gases fed into the annular chamber mix.

A process chamber with gas inlet member and the gas inlet member in the direction of flow upstream mixing chamber also shows the US 2003/0019428 AI.

The invention is based on the object to develop a gas mixing device nutzsvorteilhaft. The object is achieved by the invention specified in the claims.

The claimed gas mixing device is used as an aggregate on a CVD reactor. The CVD reactor consists of a reactor housing in which the process chamber is arranged. Substrates are to be coated in the process chamber. For this purpose, process gases are introduced into the process chamber through a suitable gas inlet element. The latter is heated so that chemical reactions can take place there. In particular, it is provided that the process gases decompose pyrolytically. First and foremost, the device consists of a mixing chamber, into which a plurality of gas lines open. The mixing chamber has a Gasumlenkeinrichtung that generates a circulating gas stream. The mixing chamber has an opening through which the circulating gas flow can pass. occurs and is passed through a pipe. The mixing chamber may be a premixing chamber if the pipe is a gas mixing pipe. In a preferred embodiment, a first Gasumlenkeinrichtung is formed as a circulation chamber, which is located in the center of the mixing chamber. The circulation chamber may have a circular cross-section. It then preferably has a diameter which is greater than the diameter of the gas outlet pipe or the gas outlet opening. However, the circulation chamber or the housing of the gas mixing device can also have a non-circular geometry, for example a polygonal floor plan. Quite generally, it is advantageous if the cross-sectional area of the circulation chamber is greater than the cross-sectional area of the gas outlet pipe or of the gas outlet opening. If a gas mixing tube adjoins the mixing chamber, the diameter is preferably also greater than the diameter of the gas mixing tube. The gas outlet opening may be located in the center of the circulation chamber. The circulation chamber may have a bottom, in the middle of which the gas outlet opening is arranged, to which the gas mixing tube adjoins. Gas guide surfaces can be arranged on the floor. These gas guide surfaces may be formed by Gasleitblechen which are mounted obliquely to the radial direction on the ground, so that an optionally pre-aligned gas flow is made to rotate. The vortex thus produced exits the opening and later into the gas mixing tube, where further Gasumlenkelemente may be located. There are preferably provided further Gasumlenkeinrichtungen. These may be surrounded by a radially outer zone. In a radially outer zone, the gas streams can be fed from the gas inlets. The second and third gas deflectors may annularly surround the circulation chamber. The second and third gas diverter means may have second and third gas diverter elements. These deflecting elements can be formed by Gasleitblechen. The Gasleitbleche are preferably designed so that they divert a radially outward to radially inwardly flowing gas flow transversely to the radial direction. The deflection can take place in the circumferential direction about the center of the mixing chamber. Preferably, the mixing chamber has arranged in a plane gas supply lines. The gas deflection can then also take place in a direction transverse to the plane. Particularly preferably, the gas flow generated by the second or third Gasumlenkeinrichtung has both a component of motion in the circumferential direction so a rotational component and a component of movement transverse to the plane in which open the gas supply lines. In a preferred embodiment, two gas deflection devices are nested radially one inside the other. They have Gasumlenkelemente acting in opposite directions. However, both Gasumlenkeinrichtungen direct the gas flow in the same transverse direction to the plane, but in opposite directions of rotation. For example, a gas diverter may impose a direction of motion component clockwise and the other a counterclockwise direction of motion component to the gas flow. A total flow flowing radially inward from an outer annular channel divides into two substantially equal partial flows, each partial flow flowing through a gas deflection device and being deflected in another direction of rotation. The gas streams deflected in opposite directions in the circumferential direction may recombine before entering the circulation chamber, where they are forced to share a common spin with which the total gas flow can enter the gas mixing tube. For example, twelve gas supply lines can be provided, which are connected in a star-shaped arrangement with an outer annular wall of the mixing chamber. Through the openings of the outer annular wall of the mixing chamber different process gases are fed into the mixing chamber at different circumferential positions. They enter into a common outer Ring channel in which the gas composition depends strongly on the circumferential position. A first mixing takes place in that the inhomogeneous gas stream is divided into two sub-streams, which is deflected in opposite directions. The gas streams leaving the second and third gas deflecting devices with different directions of rotation join together in the first gas deflecting device in which they are forced to rotate in a common direction of rotation in the course of a radial inward flow. The strongly swirling gas mixture then flows through a gas outlet opening of the bottom of the circulation chamber and into a diameter-reduced gas mixing tube, which may have a multiplicity of fourth gas deflection means, so that there takes place a further homogenization of the gas mixture. The mixing of the gas streams entering the device through the various gas supply lines can take place on two levels located one above the other. Each level forms a gas deflection volume. In each Gasumlenkvolumen are Gasumlenkelemente. It may be baffles that are arranged obliquely to a radial direction, so that they not only radially inward, but also in the circumferential direction direct the incoming gas flow, so impose on him a twist or rotation. The baffles can be flat sheets. But you can also be bent, for example, be curved in an S-shape. It is also possible to restrict the baffles so that they have a twist. As a result of this distortion, the gas flow flowing in the radial direction is deflected not only in the circumferential direction but also in the axial direction. The spaces between the baffles extending at an angle to the radial direction form flow-guiding chambers. It is advantageous if the axial height of the baffles in the flow direction, that is reduced from radially outside to radially inside. As a result, the gases can flow from one chamber into the adjacent chamber, thereby transferring the baffles. stream. There may be several, preferably two Gasumlenkvolumina arranged one above the other. The two gas volumes are separated by a separating bottom, which runs in a plane perpendicular to the axis of the device. The bottom can be located approximately halfway up the gas inlet opening, so that the gas flow entering through the gas inlet opening is divided between the two gas deflection volumes. In each of the two gas volumes, the gas is deflected in the circumferential direction. The gas deflection elements are preferably arranged so that this takes place in different directions of rotation. Thus, the gas flow flowing through the upper Gasumlenkvolumen, clockwise and the gas flow, which is fed by the lower Gasumlenkvolumen be turned counterclockwise. In a preferred embodiment, the gas stream entering through the gas inlet opening flows in the radial direction only past a gas deflecting element before the gas stream continues to flow through the gas outlet opening in the axial direction. The gas inlet openings can be arranged at a uniform angle distribution about the axis of the device. The gas inlet openings can also be located only on one side, in particular half side of the device. Preferably, however, all gas inlet openings lie in one plane. In a radially outermost annular channel into which open the gas inlet openings, one or more Gasumlenkeinrichtungen be arranged. Here, too, two Gasumlenkvolumina can be arranged one above the other, wherein the two Gasumlenkvolumina are equally supplied by the gas supply lines with gas. In each of the two Gasumlenkvolumen there is a deflection of the gases in each case a different direction of rotation.

The gas mixing chamber according to the invention is arranged upstream of a CVD reactor in the flow direction. The gas flow exiting the gas mixing tube flows into a gas inlet member of a CVD device. The inventive The gas mixing device has large-area flow cross sections and a multi-axis deflection of the gases introduced into the mixing device, the gases partly flowing against one another. The invention thus provides a gas mixing device in which the gases mix homogeneously at the lowest possible pressure drop between gas inlet and gas outlet of the gas mixing device. All flow cross sections of the mixing chamber are larger than the flow cross sections of the gas outlet tube designated gas mixing tube.

The mixing device described above is optimized for low pressures. Preferably, the mixing device is described in a pressure range of 0.2 mbar. It is designed especially for such a pressure range.

Embodiments of the invention are explained below with reference to accompanying drawings. Show it:

1 is a perspective view of a first embodiment with removed a mixing chamber 1 closing ceiling plate,

2 is a plan view of the device shown in Figure 1,

3 is a section along the line III - III in Figure 1,

4 shows a representation according to FIG. 3, wherein the section is drawn along an annular wall 11 surrounding a gas deflection element 8, 5 shows an illustration according to FIG. 3, wherein the section is drawn along an annular wall 12 surrounding a gas deflection element 16,

6 is a partially broken perspective view,

Fig. 7 dissolved out of the mixing chamber, an annular wall 12 with attached Gasumlenkelementen 8, 16,

Fig. 8 shows a broken section through a gas mixing tube 2 and

Fig. 9 in perspective Gasumlenkelemente 18, as in the

Gas mixing tube 2 are arranged,

10 is a first perspective view of a second embodiment, also here with the cover removed,

10 is a side view of the embodiment shown in Figure 10, Fig. 12 is a plan view of the embodiment shown in Figure 10, Fig. 13 is a section along the line XIII - XIII in Figure 11, Fig. 14 is a section along the line XIV XIV in FIG. 12

15 is a second perspective view of the second embodiment with partially broken annular wall 9, a perspective view of a third embodiment with the ceiling removed and with flanges removed in front of the gas supply lines 3, Fig. 17 is a side view of the embodiment shown in Figure 16,

18 shows the section according to the line XVIII - XVIII in Figure 17, Figure 19 shows the section along the line XIX - XIX in Figure 17,

Fig. 20 shows the section along the line XX - XX in Figure 17 and

21 is a second perspective view of the third embodiment with partially broken outer annular wall. 9

The devices shown in the drawings are used to homogeneously mix a plurality of different gases supplied through separate gas supply lines 3 of the device to discharge the homogenized gas flow from a gas mixing tube 2. The device can be flanged to a CVD reactor. The gas mixture emerging from the gas mixing tube 2 is fed into a gas inlet member of the CVD reactor, which introduces the gas mixture into a process chamber in which substrates rest on a susceptor to coat each other after a chemical decomposition of the process gases or a chemical reaction of the process gases to become.

The devices shown in the drawings consist of a mixing chamber 1, which can be seen in the figure 1. The ceiling 20 of the mixing chamber 1 is not shown there, so that essential entrails of the mixing chamber 1 can be seen. The mixing chamber has a flat-cylindrical housing with a circular outline. An outer wall of the mixing chamber 1 forms an annular wall 9 with a plurality, for example four, six, eight or twelve openings. At each of the openings a gas inlet flange is attached, so that a total of twelve gas supply lines 3 form.

In the first embodiment, the gas supply lines 3 open in a uniform circumferential distribution in an annular channel 10, whose outer side is bounded by the first ring wall 9 and whose inner side is bounded by a second annular wall 11 which is fixed to the ceiling 20. Under the second annular wall 11, an underflow zone 17 is formed, which is bounded from the bottom 21 of the here also the function of a premixing chamber performing mixing chamber 1 down.

At the second annular wall 11, two radially nested annular channels 13, 15 close. The third annular channel 13 is delimited in the radial outer direction by the second annular wall and in the radial direction by a third annular wall 12. The third annular wall 12 has both the ceiling 20 and towards the ground a space. The third annular wall 12 surrounds the third annular channel 15, which is surrounded on the radially inner side by a fourth annular wall 14. The fourth annular wall 14 is connected to the bottom 21 of the mixing chamber 1 and is spaced from the ceiling 20. The second gas deflecting elements 8 are located in the second annular channel 13 and are oblique to the center axis of the cylindrical mixing chamber 1. In the second annular channel 13 and in the third annular channel 15 are located approximately identically designed second Gasumlenkelemente 8 and third Gasumlenkelemente arranged. You are able to deflect a flowing from the annular channel 10 in the underflow zone 17 gas flow flowing through the second annular channel 13 from bottom to top in the counterclockwise direction. They thus give the gas stream flowing through the second annular channel 13 an angular momentum directed in the counterclockwise direction. The third Gasumlenkelemente 16, which are arranged in the third annular channel 15, are also able to redirect the bottom of the third annular channel 15 by flowing gas stream in Umf angsrichtung. However, the third Gasumlenkelemente 16 formed here by baffles force the gas flow, however, a direction of rotation in a clockwise direction.

The underflow zone 17 and the inlet cross sections of the second and third annular channels 13, 15 are designed such that approximately equal gas flows flow through the two annular channels 13, 15. The flowing from the first annular channel 10 in the underflow zone 17 gas stream is thus divided into two approximately equal partial gas flows, both side by side in the axial direction upwardly different ring channels 13, 15 flow through and are rotated in opposite directions.

In a zone immediately above the second annular channel 13 and the third annular channel 15, a strongly swirled zone is formed, in which two gas streams flow against each other. This leads to a strong mixing of the two gas streams.

Thus, initially in an annular chamber 10 a substantially radial gas flow takes place and in the radially inner annular channels 13, 15 an axial gas deflection. The recombined gas stream then flows radially inwardly into a circulation chamber 4. The circulation chamber 4 has a bottom 7 which extends at the level of the upper edge of the fourth annular wall 14. The bottom 7 is connected to the edge of the upper ring wall 14. The ceiling of the circulation chamber 4 is formed by the ceiling 20 of the mixing chamber 1.

FIGS. 1 and 2 show that first gas deflecting elements 5 are located between the floor 7 and the ceiling 20. These are web-like baffles which are connected both to the ceiling 20 and to the floor 7. The baffles 5 extend obliquely to a radial direction with respect to the center of the mixing chamber 1. A gas flow flowing radially outwards in the direction of the center thus becomes a swirling clockwise rotating swirl. With this vortex, the gas flow passes through a gas outlet opening 6 in a arranged under the bottom 7 chamber 19. At the chamber 19, a gas outlet pipe 2 connects. The inner diameter of the opening 6 substantially corresponds to the diameter of the gas outlet pipe 2.

In the gas mixing tube 2 are fourth Gasumlenkelemente 18, which are also formed by baffles and which are able to impose a vortex to the gas flowing through the gas mixing tube 2 gas. In this exemplary embodiment, the gas mixing chamber also performs the function of a premixing chamber, since further gas deflection elements 18 of a gas mixing tube 2 adjoin the gas outlet opening 22, through which the premixed gas leaves the chamber 19.

The jacket wall of the gas mixing tube 2 can be tempered. The second embodiment shown in Figures 10 to 15 has a cup-shaped housing with a flat bottom 21 and a parallel extending, but not shown in the figures cover. An outer wall 9 extending on a circular line has a multiplicity of radial openings which in each case form a gas feed line 3. Sitting at the openings

Flange sections to which pipes can be flanged. The interior of the cylindrical housing forms a circulation chamber 4. The opening cross-sections of the gas supply lines 3 extend almost over the entire axial height of the circulation chamber 4. In the middle of the circulation chamber is a bottom plate 7, which has a circular ground plan. It has in the middle of a gas passage opening 6. The bottom 7 is located centrally between the bottom 21 and the ceiling, not shown, and extends parallel thereto. The outer peripheral edge 7 'of the bottom 7 passes approximately through the middle of each gas inlet 3. The edge 7' has a radial distance to the inner surface of the annular wall. 9

The space above the intermediate bottom 7 forms a first Gasumlenkvolumen. The space below the intermediate bottom 7 forms a second Gasumlenkvolumen. In both Gasumlenkvolumina flows through the gas supply lines 3 in about the same gas flow.

At the intermediate bottom 7 Gasumlenkelemente 5 and at the bottom Gasumlenkelemente 23 are mounted on the top. The Gasumlenkelemente 5, 23 have an S-shaped configuration and are connected with a longitudinal edge to the intermediate bottom 7. One of these longitudinal edges opposite longitudinal edge 5 'and 23' is inclined. This gives the Gasumlenkelement 5, 23 a wedge-shaped shape. The upstream, ie to the gas supply 3 turned end face 5 "', 23"' has a greater axial length than the gas passage opening 6 facing end face 5 ", 23".

The Gasumlenkelemente 5, 23 of the two Gasumlenkvolumen are arranged so net that they generate opposing rotating gas streams. The Gasumlenkvolumen lying in the figures above generated with its Gasumlenkelementen 5 a gas flow in the counterclockwise direction. The underlying Gasumlenkvolumen generated with its Gasumlenkelementen 23 a clockwise gas flow. From the figure 15 it can be seen that before the mouth of each gas inlet 3, the longer end face 5 "', 23"' of Gasumlenkelementes 23, 5 is located.

In which the gas deflecting elements 5, 23 taper in the axial direction in the flow direction, ie from radially outside to radially inside, the gases entering through the gas inlet openings 3 can partially flow away via the gas deflecting elements 5, 23 before they pass through the gas outlet openings 6, 22 in the axial direction emerge from the circulation chamber 4.

The Gasumlenkelemente 5, 23 extend continuously from the Gaszu- line 3 to the gas passage opening 6 and the gas outlet opening 22. The gas passage opening 6 and the gas outlet opening 22 are axially superimposed. The mixture of the gases in the circulation chamber 4 is thus effected by only one Gasumlenkstufe, each having only one radially acting Gasumlenkelement 5, 23.

In an embodiment not shown, the Gasumlenkelemente 5, 23 are not only bent around an axis, but also transversely thereto, for example, wound around a radial axis, so that the Gasumlenkelemente 5, 23 the diverted gas flow not only a directional component in the circumferential direction, but also a directional component in the axial direction. The baffles 5, 23 here form a set of the same gas deflection elements, which extend between the gas inlet opening 3 and the gas outlet opening 6, 22. Between each of a gas inlet opening 3 and the radially inner gas outlet opening 6, 22, only a Gasumlenkelement 5, 23 extends.

The third exemplary embodiment illustrated in FIGS. 16 to 21 is similar to the first exemplary embodiment with regard to the radial division of the mixing chamber 1 into a plurality of mixing zones arranged one behind the other in the radial direction in the form of annular channels 10, 13, 15 and a central circulation chamber 4. The gas inlet, however, is similar to the gas inlet of the second embodiment shown in Figures 10 to 15.

Also, this embodiment has a circular disk-shaped bottom 21 with a central gas outlet opening 22, to which a not shown gas outlet pipe 2 can connect. The side wall of the mixing chamber is formed by a cylindrical wall 9. This annular wall has a plurality of circular openings which extend substantially over the entire axial height of the annular wall 9. An unillustrated lid closes the mixing chamber 1 and runs parallel to the bottom 21st

The gas supply lines 3 open into an outer annular channel 10. By an intermediate bottom 26 of the outer annular channel 10 is divided into two superposed Gasumlenkvolumina. In each of the two gas deflection volumes The gas deflection elements 23, 24, 25 are arranged so that they impose a component of motion in the circumferential direction to the gas flow flowing in the radial direction through the gas supply line 3. The two gas deflection volumes generate oppositely rotating rotational flows.

Again, the radially outwardly facing end edge edges of the Gasumlenkelemente 23 of the two superimposed Gasumlenkvolumina aligned with each other and cross the gas supply line 3 through its center. Through the center of the gas supply line 3 and the intermediate bottom 26 extends. A radially outer portion of each Gasumlenkelementes 23 is formed by a substantially rectilinear guide plate. The baffle extends obliquely to the radial direction. At the over the entire axial height of the Gasumlenkvolumen extending guide plate 23 is followed by a likewise extending over the entire height slightly curved portion 25 at. The section 25 extends approximately on a circular arc around the center of the mixing chamber 1. The straight section 23 of the Gasumlenkelementes an arc section 24 connects, which extends only over half the axial height of the Gasumlenkvolumens. The end 24 'of the arcuate Gasumlenk- element 24 extends approximately in the radial direction and is connected to an annular wall 11. The annular wall 11 carries on its side facing the center side Gasumlenkbleche 8, which deflects the flowing into a lower flow zone 17 of the annular wall 11 gas flow upwards and counterclockwise. Between a ring wall 14 and the annular wall 11 thus forms a second annular channel 13.

In the axial direction below the second annular channel 13 is a third annular channel 15, the center of the ring wall 14 and radially outward ßen of a third annular wall 12 is limited. This third annular wall 12 is connected to Gasumlenkelementen 24 of the lower Gasumlenkvolumens and is spaced from the bottom 21, so that an underflow zone 17 'is formed, can pass through the gas to enter the third annular channel 15 and then into the second annular channel thirteenth In the annular channel 13 there is thus a thorough mixing of the gas entering the lower gas deflection volume with the gas entering the upper gas deflection volume. The mixture flows out of the top of the second annular channel 13 and in the radial inward direction, where a central further circulation chamber 4 is arranged. The circulation chamber 4 corresponds in terms of its structure substantially to the circulation chamber described in the first embodiment, but here, the, the gas deflecting 5 forming gas baffles are curved in the plane of the bottom 7. They give the gas flowing out of the annular channel 13 a clockwise directed twist. The gas leaves through the gas passage opening 6, the topmost level and enters in a swirling axial flow in the central chamber 19, the bottom 21, the gas outlet opening 22, to which an unillustrated gas outlet pipe is connected. The above explanations serve to explain the inventions as a whole, which in each case independently develop the prior art at least by the following combinations of features, namely: a device which is characterized in that the first gas deflecting device 4, 5, 18, 23, 24, 25 is arranged in the mixing chamber 1. A device, which is characterized in that the gas deflecting device 4, 5 has a circulation chamber 4, with a chamber cross-sectional area which is greater than the cross-sectional area of the gas outlet tube 2 or the gas outlet opening 6, 22nd

A device characterized by a first gas outlet opening 6, which is arranged in the center of the bottom 7 of the circulation chamber 4 and which opens into the gas outlet pipe 2. A device, characterized in that the Gasumlenkeinrichtung 4, 5 Gasleitflächen 5, 18, 23, 24, 25 in order to impose a swirling radially into the circulation chamber 4 gas flow, wherein the Gasleitflächen 5, 18, 23, 24, 25 are formed in particular of at a bottom 7, 21, 26 fixed webs.

A device characterized by first, second and / or third Gasumlenkelemente 5, 8, 16, 23, 24, 25, with which the fed into a radially outer zone 10 of the mixing chamber 1 gas flows are deflected transversely to the radial direction.

A device, which is characterized in that the gas streams fed into a radially outer zone 10 of the mixing chamber 1 are deflected in the circumferential direction and / or that by means of two Gasumlenkeinrichtungen 8, 13; 15, 16 two gas streams are generated, wherein one is deflected in a clockwise direction and / or a counterclockwise direction and at least one flows into the circulation chamber 4 in the radial direction. A device, which is characterized in that the second and / or third Gasumlenkelemente 8, 16, 23, 24, 25 are each associated with an annular channel 13, 15. A device which is characterized in that a plurality of gas supply lines 3 open in a star-shaped manner into a radially outer annular channel 10, to which an underflow zone 17, 17 'adjoins in radial inward direction, whereby the gas stream coming from the annular channel 10 is of substantially equal volume Distribution divided into two gas streams, each by an annular channel 13, 15 with second and third Gasumlenkeinrichtungen 8, 13; 15, 16 flow, reunite downstream of the annular channels 13, 15 and flow from radially outside into the circulation chamber 4.

A device, characterized in that the gas supply lines lie in a common plane and are arranged around the circulation chamber 4, wherein the axis of the gas outlet tube 2 is perpendicular to this plane.

A device which is characterized in that fourth gas deflecting elements 18 are arranged in the gas outlet pipe 2.

A device which is characterized in that the Gasumlenkelemente 5 baffles having an axial height, which decreases from radially outside to radially inside.

A device characterized by two Gasumlenkvolumina into which the gas supply lines 3 open, wherein the Gasumlenkvolumina in the axial direction by a bottom 26, 7 are separated from each other and each Gasumlenkele 5, 23, 24, 25, with which the radially flowing into the respective Gasumlenkvolumen gas flow is deflected in a rotational movement about the axis, the Gasumlenkelemente 5, 23, 24, 25 of the different Gasumlenkvolumina gas flows generate in different directions.

A device which is characterized in that between the gas supply line 3 and the gas outlet opening 6, 22 only one set of identically designed Gasumlenkelement 5, 23 is arranged. A device characterized in that the gas deflecting element 5, 23, 24, 25 has an arcuate shape.

The use of a device of the type described above at a total pressure of less than 10 mbar, preferably less than 1 mbar, preferably at 0.2 mbar.

All disclosed features are essential to the invention (individually, but also in combination with one another). The disclosure of the associated / attached priority documents (copy of the prior application) is hereby also incorporated in full in the disclosure of the application, also for the purpose of including features of these documents in claims of the present application. The subclaims characterize with their features independent inventive developments of the prior art, in particular to make on the basis of these claims divisional applications. LIST OF REFERENCE NUMBERS

1 mixing chamber 22 gas outlet opening

2 gas mixing tube / gas outlet tube 23 Gasumlenkelement

3 gas supply line 23 'longitudinal edge

4 circulation chamber 23 "front side

5 Gasumlenkelement (first) 23 '"front side

5 'longitudinal edge 24 Gasumlenkelement

5 "front side 24 'end

5 '' end 25 Gasumlenkelement

6 gas outlet opening 26 floor

7 soil

7 'edge

8 gas deflector (second)

9 ring wall (first)

10 ring channel (first)

11 ring wall (second)

12 ring wall (third)

13 ring channel (second)

14 ring wall (fourth)

15 ring channel (third)

16 gas deflector (third)

17 underflow zone

17 'flow zone

18 gas deflector (fourth)

19 chamber

20 blanket

21 floor

Claims

EXPECTATIONS

1. Device for mixing several gases together, with a plurality of gas supply lines (3) which open into a mixing chamber (1), with a gas deflection device (4, 5, 18, 23, 24, 25) to generate a circulating gas stream and with a gas outlet opening (6, 22) or a gas outlet pipe (2), into which the gas outlet opening (22) opens, from which the gas streams fed into the mixing chamber (1) through the gas supply lines (3) flow out of the mixing chamber (1), characterized that the first gas deflection device (4, 5, 18, 23, 24, 25) is arranged in the mixing chamber (1).

2. Device according to claim 1, characterized in that the gas deflection device (4, 5) has a circulation chamber (4) with a chamber cross-sectional area that is larger than the cross-sectional area of the gas outlet pipe (2) or the gas outlet opening (6, 22).

3. Device according to one of the preceding claims, characterized by a first gas outlet opening (6) which is arranged in the center of the bottom (7) of the circulation chamber (4) and which opens into the gas outlet pipe (2).

4. Device according to one of the preceding claims, characterized in that the gas deflection device (4,

5) has gas guide surfaces (5, 18, 23, 24, 25) in order to impose turbulence on a gas stream flowing radially into the circulation chamber (4), the gas guide surfaces (5, 18, 23, 24, 25) in particular on a floor (7, 21, 26) attached webs are formed.

Device according to one of the preceding claims, characterized by first, second and/or third gas deflection elements (5, 8, 16, 23, 24, 25) with which the gas streams fed into a radially outer zone (10) of the mixing chamber (1). be deflected transversely to the radial direction.

6. Device according to one of the preceding claims, characterized in that the gas streams fed into a radially outer zone (10) of the mixing chamber (1) are deflected in the circumferential direction and / or that by means of two gas deflection devices (8, 13; 15, 16) two gas streams are generated, one being deflected clockwise and/or one counterclockwise and at least one flowing into the circulation chamber (4) in the radial direction.

7. Device according to one of the preceding claims, characterized in that the second and / or third gas deflection elements (8, 16, 23, 24, 25) are each assigned to an annular channel (13, 15).

8. Device according to one of the preceding claims, characterized in that a plurality of gas supply lines (3) open in a star shape into a radially outer annular channel (10), which is followed by an underflow zone (17, 17 ') in the radially inward direction, the The gas stream coming from the annular channel (10) is divided into two gas streams in a substantially equal volume distribution, each of which flows through an annular channel (13, 15) with second and third gas deflection devices (8, 13; 15, 16), downstream of the annular channels (13 , 15) again combine and flow into the circulation chamber (4) from the radial outside.

Device according to one of the preceding claims, characterized in that the gas supply lines lie in a common plane and are arranged around the circulation chamber (4), the axis of the gas outlet pipe (2) running perpendicular to this plane.

Device according to one of the preceding claims, characterized in that fourth gas deflection elements (18) are arranged in the gas outlet pipe (2).

Device according to one of the preceding claims, characterized in that the gas deflection elements (5) are baffles which have an axial height which decreases from radially outside to radially inside.

12. Device according to one of the preceding claims, characterized by two gas deflection volumes into which the gas supply lines (3) open, the gas deflection volumes being separated from one another in the axial direction by a base (26, 7) and each gas deflection elements (5, 23, 24, 25 ) with which the gas stream flowing radially into the respective gas deflection volume is deflected into a rotational movement about the axis, the gas deflection elements (5, 23, 24, 25) of the different gas deflection volumes generating gas flows in different directions of rotation.

13. Device according to one of the preceding claims, characterized in that only one set of identically designed gas deflection elements (5, 23) is arranged between the gas supply line (3) and the gas outlet opening (6, 22).

14. Device according to one of the preceding claims, characterized in that the gas deflection element (5, 23, 24, 25) has an arcuate shape.

15. Use of a device according to one or more of the preceding claims at a pressure range of less than 10 mbar, preferably less than 1 mbar, preferably at 0.2 mbar.

16. Device or use of a device, characterized by one or more of the characterizing features of one of the preceding claims.