DE102009023125A1 - Manufacturing serially switched thin-film solar cells, comprises arranging a semi-finished product with a rigid carrier substrate onto a reception, and introducing the semi-finished product in a deposition chamber with a deposition device - Google Patents

Abstract

The method comprises arranging a semi-finished product (10) with a rigid carrier substrate (12) onto a reception, introducing the semi-finished product in a deposition chamber with a deposition device, bringing a masking device with a strand-like masking agent (30a, 30b), which is present in a longitudinal direction under prestress, onto a surface of the semi-finished product turned to the deposition device, and partially shading the surface of the semi-finished product using the masking device against the deposition device for structuring a material layer to be deposited. The method comprises arranging a semi-finished product (10) with a rigid carrier substrate (12) onto a reception, introducing the semi-finished product in a deposition chamber with a deposition device, bringing a masking device with a strand-like masking agent (30a, 30b), which is present in a longitudinal direction under prestress, onto a surface of the semi-finished product turned to the deposition device, partially shading the surface of the semi-finished product using the masking device against the deposition device for structuring a material layer to be deposited, depositing the material layer on the semi-finished product, and removing the masking device from the surface of the semi-finished product. The strand-like masking agent contains filaments (32, 34) lying on each other. The carrier substrate consists of glass, glass ceramic material, wafer, plastic or metal. The semi-finished product is convexly bulged in relation to the deposition device. The strand-like masking agent carries out a relative movement against the semi-finished product in the longitudinal direction of the masking agent during the deposition of the material layer, is continuously or quasi-continuously fed and discharged in the longitudinal direction, is guided with a guide roller or is directed by a centering unit, and is loaded in vertical to the surface of the semi-finished product by a holding down device transverse to its longitudinal direction. The holding down device has the guide roller and the centering unit. The strand-like masking agent is prestressed in the longitudinal direction by a spring. Several material layers are deposited on the semi-finished product under the utilization of the deposition chambers. The masking agent is displaced between the deposition of the material layers onto the surface of the semi-finished product transverse to its longitudinal direction to allow contact or separation of determined material layers. The deposition of the material layers and the displacement of the masking agent take place in process gas atmosphere or in vacuum. The displacement of the masking agent takes place in a separate displacement chamber. A transfer takes placer between the deposition and displacement steps, in which the semi-finished product is exposed to the process gas atmosphere or vacuum. The contaminants or residues of the deposited material layers are removed from the masking device by an etching process. An independent claim is included for a device for manufacturing serially switched thin-film solar cells.

Description

The The invention relates to a method for the production of serially connected Thin-film solar cells, which arrange the steps of a Semi-finished product with a rigid carrier substrate on a receptacle, introducing of the semifinished product in a deposition chamber with a separator and depositing a layer of material on the semifinished product.

solar cells in particular based on the thin-film technology due to low material consumption during the production of the active layers and a high potentially achievable efficiency. To reduce ohmic losses and to provide a high output voltage become the active layers of solar cells usually structured on the substrate and connected in series with each other.

When Substrate for the production of solar cells based Thin-film technology can be rigid materials be used, because this way the very thin layers can be arranged on a firm basis, whereby increase the mechanical stability and the Can simplify handling during production.

A method for producing an interconnection of thin-film solar cells with glass substrates is known from WO 2007/044555 A2 known. Here, in a first process, active and conductive layers are deposited on a substrate, wherein then individual or all layers are separated by a laser or by mechanical scribing to apply a printing process or by electroplating an additional conductive layer for the specific connection of certain active layers.

In an alternative method follows the deposition process respectively a cutting process. This is the last deposited Layer, possibly together with other layers, separated to with the subsequent layer targeted conductive or active To bring material into the separation area. After this the top conductive layer, the front contact, applied is, then this layer, if necessary together with further layers, cut open to a short circuit of the front contacts to prevent neighboring solar cells.

On In this way it is basically possible to use solar cells in thin-film technology on glass substrates. However, it has been found that such methods are particularly complicated and therefore very expensive, since each applied Layers in an additional process for the purpose of interconnection again have to be partially removed. Therefor separate expensive laser cutting systems or mechanical scoring systems are necessary. In addition, according to the method, the glass substrate must be between a deposition and a cutting process are transferred, respectively the deposition process takes place in a vacuum chamber and the cutting process done in separate devices. The transfer is taking shape particularly complex, since each one is passed through a vacuum lock and moreover an adaptation of the substrate temperature to each of the deposition under vacuum or during the cutting process prevailing process temperatures must be made.

Of Further, by repeated input and removal of the substrate the risk of contamination of both the substrate and the Separator and the cutting device rise. This can to reduced process quality and waste production to lead.

From the WO 2007/085343 A1 a method for the production of series-connected solar cells with flexible substrates is known in which the substrate is applied in a deposition device on a curved support surface and shadowed by means of at least one tensioned wire which rests on the substrate, opposite the deposition device. Thus, the applied material layer is already structured during the deposition. Advantageously, the tensioned wire can be biased relative to the flexible substrate such that a sufficiently wide contact surface results by deformation of the substrate instead of a mere line contact, in the area no material can be deposited.

About that In addition, it is envisaged that both the flexible substrate and the wire of the separator continuously or quasi-continuously fed be a continuous generation of a structured material layer on the flexible carrier substrate in a continuous process to enable.

It However, it has been shown that a production of such solar cells with flexible substrates on an industrial scale only with high cost is possible. Also have such solar cells only limited mechanical stability and thus need in some applications with separate carrier and protective layers be provided.

The method is particularly not suitable for the production of thin-film solar cells with rigid substrates, since the wire can not shadow the rigid substrate due to the lack of curvature and lack of elasticity on the substrate surface against the separator, which is flaws, esp dered short circuits in the structuring of the deposited material layer can result.

On the other hand the production of solar cells on glass substrates is widespread and and tested on a large scale. However, a serial interconnection of such solar cells is expensive and expensive.

In front In this background, the invention is based on the object improved process for the production of thin-film solar cells specify with rigid substrates, preferably for a cheap, automated production is suitable. Further should be suitable for carrying out this method Device can be specified.

• – Anordnen eines Halbzeuges mit einem starren Trägersubstrat auf einer Aufnahme;
• – Einbringen des Halbzeuges in eine Abscheidekammer mit einer Abscheideeinrichtung;
• – Aufbringen einer Maskiereinrichtung mit mindestens einem strangförmigen Maskiermittel, das in Längsrichtung unter Vorspannung steht, auf eine der Abscheideeinrichtung zugewandten Oberfläche des Halbzeuges;
• – partielles Abschatten der Oberfläche des Halbzeuges mittels der Maskiereinrichtung gegenüber der Abscheideeinrichtung zur Strukturierung einer abzuscheidenden Materialschicht;
• – Abscheiden der Materialschicht auf das Halbzeug; und
• – Lösen der Maskiereinrichtung von der Oberfläche des Halbzeuges.

This object is achieved by a method for producing serially connected thin-film solar cells with the following steps:

• Arranging a semifinished product with a rigid carrier substrate on a receptacle;
• - Introducing the semifinished product in a deposition chamber with a separator;
• - Applying a masking device with at least one strand-shaped masking agent, which is biased in the longitudinal direction, on a deposition of the device facing surface of the semifinished product;
• Partial shading of the surface of the semifinished product by means of the masking device with respect to the deposition device for structuring a material layer to be deposited;
• - depositing the material layer on the semi-finished product; and
• - Release the masking of the surface of the semifinished product.

The The object of the invention is completely solved in this way.

According to the invention namely by the masking device with the strand-shaped Masking a particularly good and safe shading of the semifinished product with the rigid carrier substrate opposite the separator causes. The strand-shaped masking agent must have a Have a thickness of at least 20 microns. Also has to be given sufficient elasticity so that (instead of a linear) a surface contact between the rigid support substrate and the strand-like Masking agent results. Otherwise, there is no sufficient shading more guaranteed, so the risk of short circuits consists.

The Structuring of the deposited material layer according to the invention already be achieved during the deposition process. It can therefore even with thin-film solar cells with rigid substrates on separate separation processes for structuring a material layer be waived. A cheap, automatable production can be realized by on a large scale proven systems for the production of solar cells on glass substrates can be used.

The strand-shaped masking ensures a high process reliability, as even with only slight curvature the substrate ensures reliable shading so that the coating produces clean, uncoated release surfaces, be avoided by the short circuits.

Under a "rigid carrier substrate" is in frame this application understood a carrier substrate, the in Contrary to a flexible carrier substrate only in limited Dimensions is bendable, so with a maximum deflection allowed a bending radius of ≥ 100 cm. In this case it could be about a plate made of a glass, a glass-ceramic material or act from a wafer. In the narrower sense is one among them Carrier substrate understood that a maximum deflection allowed with a bending radius of ≥ 20 cm. Below it comes it destroys or damages z. B. a permanent deformation of the substrate. So it turned out that glass plates tend to break at a smaller bend radius, Support substrates in the form of rigid plastic plates or Metal plates are damaged by z. B. break or permanently deformed.

As already mentioned, it may be in the rigid carrier substrate to be a substrate made of a glass, a glass-ceramic material, a wafer, a plastic or a metal.

On This way, various glass, glass-ceramic materials or wafers are used to the rigid carrier substrate to build. Preferably, materials can be used Be special for electronic applications are suitable, such. B. borosilicate glass with a proportion of barium oxide and alumina. Form suitable glass and glass ceramic materials a highly effective diffusion barrier, allowing for extra Measures can be dispensed with in this regard. Also Wafers can be used as carrier substrates.

About that In addition, plastic plates and metal plates are basically suitable as carrier substrates.

In a preferred embodiment, the strand-shaped masking means on a plurality of adjacent filaments. In the context of this application, "filament" is understood as meaning any type of elongated element. It may therefore be a wire made of metal to a thread made of plastic, z. B. of polyamide, or of a high strength material such. B. aramid act. In addition, other inorganic materials that can be pulled out to threads or fibers conceivable, such. In any case, a continuous, tensile filament must be found which has a thickness of at least 20 microns. In addition, especially when using only a single filament this must be so far deformable when resting on the rigid support substrate that results in a sheet-like contact, not only a linear contact between the rigid substrate and the strand-shaped masking agent. Otherwise, sufficient shading is not guaranteed, so there is a risk of short circuits.

Become several, adjacent filaments used, then arise already thereby spaces, which shielded to the outside are and thus a good shield against the plasma to ensure.

In Advantageous development of the invention, the semifinished product is convex arched relative to the separator.

On this way can be achieved, that when applied Masking agent, which is biased in the longitudinal direction, a force component in the direction of the surface of the semifinished product results. This makes the masking agent particularly effective against the semifinished product can be biased and it can be an even better shading the surface of the semi-finished product relative to the separator result.

In In this context, it should be noted that the bending stresses in the Semifinished product with the rigid carrier substrate clearly below the critical strength values can remain. Considering the high rigidity of the rigid support substrate leaves Consequently, cause a slight curvature, which, however significantly contribute to the further improvement of process safety can.

In preferred development of the invention performs the at least a masking agent during the deposition of the material layer relative to the semi-finished a relative movement in the longitudinal direction of Masking agent off.

By This measure can be a particularly effective shading of the semifinished product relative to the separation device and the process-related deposition of the material layer to be deposited on the masking agent can be significantly reduced. Consequently the process quality can continue to improve and the Effort for cleaning the masking with the masking agent can be reduced.

in the According to this application, the relative movement between the semifinished product and the masking agent in the longitudinal direction of the masking agent both by movement of the semifinished product relative to the stationary one Masking agent or by movement of the masking agent opposite the dormant semi-finished as well as by simultaneous movement of the Semi-finished and the masking agent done. The can Movements in opposite directions or in the same direction be different absolute speeds.

According to one Another embodiment of the invention, the at least one masking agent in the longitudinal direction continuously or quasi-continuously added and removed.

Consequently The process can be automated particularly well because the masking agent For example, in the circulation process or in the roll-to-roll process and can be dissipated.

In preferred development of the invention, the at least one Masking carried out with at least one guide roller or aligned by at least one centering means.

On This way, a particularly accurate, targeted delivery of the masking agent can cause Abschattungsverluste minimized and thus the process accuracy and quality can still be further increased. By appropriate leadership and alignment of the masking agent with guide rollers and / or Centering can also be the contiguous filaments the masking agent are supported to the effectiveness the shading further increase.

According to one Another embodiment of the invention, the at least one masking agent a hold-down device transverse to its longitudinal direction, essentially perpendicular to the surface of the semifinished product loaded.

Also By this measure, a force component can be vertical be effected to the surface of the semifinished product, the one solid support of the masking agent on the surface of the Semifinished promote and thus the shading of the surface of the semifinished product with respect to the separating device on can improve.

In an alternative embodiment of the invention, the hold-down device has the at least one Guide roller or the at least one centering on.

hereby can perform various functions, holding down, aligning and the guiding, combined, thereby increasing the manufacturing process can be significantly simplified.

In Advantageous development of the invention, the at least one Masking in the longitudinal direction by a tensioning means, in particular a spring, pretensioned.

On this way, the bias can be applied very easily, z. B. by the clamping means directly on the masking agent with its filaments attacks or by the tensioner with the guide roller or the hold down cooperates to indirectly a Preload in the masking agent to initiate.

According to one Another embodiment of the invention, several layers of material deposited on the semifinished product using several deposition chambers.

hereby it is made possible to the deposition process of each to use deposited layer adapted deposition chambers, whereby the cleaning or rinsing effort can be reduced can and does improve manufacturing productivity results. In particular, can be highly automated for manufacturing Cluster or line arrangements with several specialized separation chambers be used.

In expedient development of the invention between the deposition of the material layers, the at least one Masking agent transverse to its longitudinal direction on the surface of the semifinished product to make a contact or separation allow certain material layers.

On in this way, it is possible to connect thin-film solar cells connected in series Produce particularly effective, since now each layer of material separately be structured and the previous separation structure for deposition a new material layer can be released. This can To be deposited material to adhere to the old separation structure, whereby different material layers particularly effective and easy contacted can be.

In Advantageous development of the invention, the deposition takes place the material layers and the at least one masking agent in a process gas atmosphere or in vacuum.

Consequently need the semifinished product and the masking device for the displacement of the masking agent not from the process gas atmosphere or led out of the vacuum. It can become one Reduction of the production time results and the production leaves Automate yourself even better. Furthermore, lock operations for adapting the semifinished product or the masking device to the Process conditions are avoided, there are fewer impurities on and less process residues can escape into the environment. In addition, the substrate remains at the same temperature, what the component quality is beneficial.

According to one Another embodiment of the invention, the displacement of at least a masking agent in a separate offset chamber.

On this way a specialized offset chamber can be used to further increase manufacturing productivity. Furthermore, the series suitability of the method improves, since now known deposition chambers without special installations for Displacement of the masking agent can be used.

In expedient development of the invention takes place a transfer between the deposition and the displacement in which the semifinished product continues to the process gas atmosphere or the Vacuum is exposed.

By This measure can also affect the manufacturing steps for series-compatible specialization with several separation chambers, an offset chamber and a transfer between the deposition and the putting still in the process gas atmosphere or done in a vacuum.

According to one Another embodiment of the invention by cleaning, in particular etching processes, Dirt and residues of the deposited Material layers removed from the masking device.

On this way, the cleaning of the masking in the manufacturing process be integrated, in particular can be established for this purpose Technologies and existing cleaning facilities of each Chambers are used.

The object of the invention is further achieved by a device for producing serially connected thin-film solar cells having at least one deposition chamber with a deposition device, with a receptacle for receiving a semifinished product with a rigid carrier substrate, in particular a carrier substrate made of a glass material, and with a masking device, the can be applied to the semifinished product, wherein the masking device at least one strand-shaped masking agent, the in Can be biased longitudinally and for partial deposition of the semifinished product relative to the separator relative to the semifinished is aligned.

According to one Development of the device according to the invention the strand-shaped masking means has a plurality of on adjacent filaments.

Thereby the shading is further improved.

According to one further embodiment of the invention Device is the receptacle for receiving the semi-finished in relation executed on the separator convex curved.

In expedient development of the invention Device has these a plurality of spaced apart Masking on.

In Advantageous development of the invention Device has these a plurality of deposition chambers for deposition the material layers, an offset chamber with a shifter with offset means for displacing the at least one masking agent transverse to its longitudinal direction relative to the surface of the semifinished product and a handling chamber with a handling device for feeding the semifinished product into the chambers.

According to one further embodiment of the device according to the invention a vacuum can be applied to the chambers or a process gas can be supplied.

With Such a device can be the inventive Perform procedures to get an improved, favorable and automatable production of thin-film solar cells to perform on rigid substrates.

It it is understood that the above and the following to be explained features of the invention not only in the specified combination, but also in other combinations or used alone, without the scope of the present To leave invention.

Further Features and advantages of the invention will become apparent from the following Description of preferred embodiments with reference on the drawings. Show it:

1 a sequence of layer structures of a semifinished product during the production of solar cells using the method according to the invention;

2 a schematic layer structure of integrated interconnected thin-film solar cells with indicated Maskiermittelpositionen;

3 a section through various masking agents for carrying out the method according to the invention;

4 an arrangement for guiding and aligning the masking agent;

5 another arrangement for guiding and aligning the masking agent;

6 a schematic section through a deposition chamber according to the present invention along the line VI-VI in 7 ;

7 a schematic section of a masking along the line VII-VII in 6 ;

8th a schematic section through an offset chamber according to the present invention along the line VIII-VIII in 9 ;

9 a schematic section of a shifter according to the line IX-IX in 8th ;

10 two schematic representations of an offset chamber according to the invention;

11 a further schematic representation of a deposition chamber according to the invention;

12 a schematic sequence of a method according to the invention;

13 a schematic representation of an apparatus for performing the method according to the invention; and

14 a further schematic sequence of the method according to the invention.

1 shows a sequence of layer structures one with the numeral 10 designated semifinished product during the production of serially interconnected thin-film solar cells using the method according to the invention.

In 1a is the semi-finished product 10 only from a rigid carrier substrate. masking 30a . 30b with filaments 32 . 34 are applied and serve the structuring of a deposited material layer.

1b shows the condition of the semi-finished product 10 ' for example after a first deposition process. This was a back contact layer 14a . 14b applied according to the masking agent 30a . 30b in 1a is structured. By an offset process have the masking agent 30a . 30b ' On the surface of the semi-finished product, a new layer was taken immediately next to their old positions in order to structure a next layer to be deposited.

In 1c is the semi-finished product 10 '' shown after a second deposition. This became an active layer 16a . 16b structured isolated. By a recent offset process have the masking agents 30a '' . 30b '' have taken a new position and can now structure a third layer of material to be deposited.

The layer structure of the semifinished product 10 ''' after this deposition shows 1d , A front contact layer 18a . 18b was deposited in a structured manner. The result is an exemplary structure of thin-film solar cells with a carrier substrate 12 , a structured back contact layer 14 , a structured active layer 16 and a structured front contact layer 18 , Due to the partial shading and thus the structuring of the material layers 14 . 16 . 18 is now a serial contacting of two solar cell arrangements 14a . 16a . 18a and 14b . 16b . 18b generated since the front contact 18a the one solar cell array with the back contact 14b the second solar cell assembly is in communication.

The arrangement according to 1 is intended to be understood only as illustrative and not in a limiting sense, since in particular the active layer 16 can be constructed from a plurality of sub-layers. The back contact layer 14 is advantageously made of conductive, reflective materials such. As silver or aluminum, during the front contact 18 preferably made of conductive, transparent materials, such. B. aluminum-doped zinc oxide is formed.

at Thin-film solar cells is the formation of individual Layers by deposition or other suitable coating and conversion procedures. In particular, the chemical are suitable Vapor deposition, z. As the plasma-assisted chemical Vapor deposition or physical vapor deposition, such as z. As the vapor deposition or sputtering.

Under Thin film can thin layers solid substances in the micron to the nanometer range understood be at least those in relation to a carrier substrate are made significantly less thick. It has to be added that for better understanding in the figures, these thickness ratios not shown to scale.

In 2 is a schematic series-connected solar cell array with a further layer sequence of a semifinished product 10 shown in the production of thin-film solar cells. The active layer 16 is further subdivided in the form of pin transitions. Such a transition may be, for example, an n-layer 20a . 20b . 20c with n-doped silicon, an adjoining intrinsic absorber layer 22a . 22b . 22c with undoped silicon and finally a p-layer 24a . 24b . 24c having p-doped silicon.

at Silicon-based solar cells may be amorphous or crystalline, in particular Also micro or nanocrystalline silicon come to use.

Of the shown layer structure is only as an exemplary embodiment to understand the active layer of thin-film solar cells based on semi-finished products with rigid substrates can also thin Layers of alternative materials such as gallium arsenide, cadmium telluride or according to the CIGS technology copper, indium, Gallium, sulfur or selenium. It is also conceivable, instead Provide the p-i-n transitions p-n junctions.

It goes on to understand that with the inventive Process also called tandem cells or packed solar cells with several consecutive p-i-n or p-n junctions can be made to solar cells with higher To realize energy yield.

In addition, it goes without saying that the carrier substrate 12 as a carrier for other passive and active devices such. B. protection diodes or contact terminals can serve or for receiving elements to protect against environmental influences, such. B. front covers or Vergussanordnungen can be used.

Of Furthermore, it is conceivable with the invention Method Material layers on the semi-finished suitable parallel to so that instead of a higher output voltage, as it is to be effected by the serial interconnection, higher Amperages result. Also are any combinations conceivable of parallel and serial interconnection.

2 also shows, indicated by dashed circles, the various positions of the masking agent to be taken 30a . 30b during a production of the solar cells according to the invention 11a . 11b . 11c , As described above, shading during a deposition process and subsequent displacement of the masking agent can be achieved 30a . 30b structuring such that the p-layer 24a the solar cell 11a with the n-layer 20b the solar cell 11b contacted and here through the serial connection of the solar cell 11a with the solar cell 11b is possible.

It should be noted that the representation of the masking agent 30 Again, for reasons of clarity, not to scale, as this is usually designed to be much thicker than the layer thickness of the deposited material layers.

In this context, without limiting the generality to conventional dimensions of the solar cell according to the invention 11b To be received. The cell width is in 2 With 26 and may typically be approximately in the range of 8 to 12 mm, in particular approximately 10 mm. In contrast, the process width as a measure of the surface losses of the solar cell, and thus for the determined by the process loss of efficiency, with 28 designated. The process width 28 Consequently, results in the example of a solar cell produced by a method according to the invention 11 from the two-time offset of the masking agent 30 that is about three times the width of the masking agent 30 ,

In 1 and 2 has the masking agent 30 two filaments each 32 . 34 on, the z. B. each may have a diameter of 0.03 mm to 0.2 mm. This results in a process width in this example 28 from about 0.18 mm to 1.2 mm, for efficiency considerations of cell width 26 is deducted. Consequently, with the method according to the invention, depending on the number and size of the filaments of the masking agent 30 a small area loss of about 12% up to values significantly smaller than 5% can be realized.

3 represents possible embodiments of the cross section of the strand-shaped masking agent 30a . 30b dar. The masking agents 30a and 30b each have 3 filaments, which lie against each other according to the invention.

The masking agent 30a has three filaments arranged in one plane 32a . 34a . 36a , This arrangement on the surface 74 of the semifinished product 10 is particularly well suited to avoid short circuits in the material to be deposited. Ideally, there are three lines of contact and a sufficiently large uncoated area can form between them. Even with a failure of one of the three line touches, e.g. B. by lifting a filament from the surface and thereby causing penetration of the material layer to be deposited in the shaded space can still structuring of the surface by the remaining filaments 74 be enabled.

According to 3 has the masking agent 30b about a filament 34b that is not on the surface itself 74 of the semifinished product 10 rests, but is particularly suitable, the filaments 32b . 36b safe on the surface 74 impose. This can be done by the concern of the filament 34b on the filaments 32b and 36b the shaded area will be maintained even if the filament 32b and the filament 36b should not rest against each other.

In the 3 shown filaments 32 . 34 . 36 all have a circular cross-section. This should not be understood as a limitation, but it is also possible to use filaments with deviating shape, such as those with oval cross-sections, rectangular, square or triangular cross-sections with or without rounded edges. In particular, this can increase the number of possible line contacts.

It is also possible to use filaments of various cross-sectional shapes and sizes in a masking agent 30 provided.

The filaments 32 . 34 . 36 can be made of metal materials, plastics, glass, aramid or carbon fibers or suitable combinations of materials such. B. overmoulded steel cores or braided materials may be formed.

As described above, it is beneficial to use the masking agent 30 so opposite to the semifinished product 10 to guide or align that contiguous to the filaments 32 . 34 . 36 is supported. Show accordingly 4 and 5 two ways to guide or align the masking agent 30 with a leadership role 42 or a centering strip 46 ,

4 thus provides a rotationally symmetrical guide roller with a centering 44 in the form of a V-groove and 5 a solid centering strip 46 with a centering device 44 also in the form of a V-groove.

This ensures that when using the masking agent according to the invention 30 with a plurality of filaments 32 . 34 an alignment on a filament, in the embodiments of the numeral 34 designated, which serves as a reference for the orientation through the V-groove. Thus, the position of the masking agent becomes 30 clearly based on the filament 34 certainly.

The masking agent 30 is under bias according to the invention. Particularly advantageous may now be in alignment of the filaments 32 . 34 through the centering means 44 with a V-groove on the filament 32 give a force component which the filament 34 additionally against the semi-finished product 10 can press.

It is also conceivable that with a suitable design of the centering 44 the example configurations of the masking agent 30a . 30b according to 3 or other suitable masking configurations can also be aligned relative to the semifinished product by means of arrangements with guide rollers or centering strips.

It It has been shown that even a single filament on a rigid Carrier substrate safe shading and thus avoidance of shorts. So revealed the use of a wire of 50 microns in thickness existing filament on a support substrate made of glass a sufficiently sharp shading. With such a diameter the wire is already so flexible that a flat Edition also results on a rigid carrier substrate, so that safe shading is ensured and short circuits be avoided.

In the 6 and 7 becomes a deposition chamber 70 with a hold-down device 80 shown for performing the method according to the invention. At the beginning, it should be mentioned that the curvature of the semi-finished product 10 This is shown oversubscribed for clarity.

semi-finished 10 with rigid carrier substrates are considered stiff and generally have high coefficients of elasticity. Consequently, only small deformations can be effected so that critical voltage characteristics, eg. B. the bending tensile strength in glass materials, are not exceeded by the deformation process.

The semi-finished product 10 is on a recording 76 arranged and opposite a separator 72 bulge. This curvature can by the weight of the semi-finished product 10 carried out by suitable means, for example by holders 62a . 62b , The holders 62a . 62b can also be used advantageously to edge regions of the semifinished product 10 opposite the separator 72 shade in order to avoid material deposits and thus unwanted contacts in these areas.

In the deposition chamber 70 is a hold-down device 80 arranged, which is a masking device 60 with masking agents 30 for partial shading and structuring of the surface 74 of the semifinished product 10 opposite the separator 72 having. For guiding the masking agent 30 are these leadership roles 42a . 42b assigned to the frame parts 66a . 66b the hold-down device are provided. Particularly advantageous are the guide rollers 42a . 42b just as used to the masking agents 30 opposite the semifinished product 10 additionally to bias. The masking agents 30 be through clamping means 56 biased in the form of springs. In the example shown are the clamping means 56 directly into the masking agent 30 nonetheless, other implementations are external to the maskants 30 introduced biasing forces conceivable.

During the deposition process can now with the hold-down device 80 with the masking device 60 a secure exact hold of the semi-finished product 10 on the recording 76 and a structuring of the material layer to be deposited can be realized.

In the 8th and 9 Now a subsequent process step is shown. In an offset chamber 84 with a misalignment device 86 the inventive displacement of the masking agent takes place 30 , about a solar cell array according to 1 or 2 manufacture. In 8th is shown that now the hold down 80 with the masking device 60 with the masking agents 30 as by the arrows 90a . 90b indicated, from the semifinished product 10 is lifted off. These are lifting means 88a . 88b , provided for example in the form of threaded spindles or pneumatic cylinders. The semi-finished product 10 will continue with owners 62a . 62b on the recording 76 fixed.

After this, an offset can now be made, for example according to the figure 94 designated double arrow in 9 , The offset movement is via offset means 92a . 92b introduced, which in turn are designed in the form of threaded spindles or pneumatic cylinders. In this case, there is a relative movement between the semifinished product 10 that on the recording 76 is fixed, and the offset device 86 , This is followed by a step in which the hold-down device 80 back to the surface 74 of the semifinished product is lowered to the masking agent 30 apply and a bias against the semifinished product 10 to be able to produce. Now another material layer to be structured and deposited can be applied.

It is understood that the arrangements of the deposition chamber 76 according to 6 and the offset chamber 84 according to 8th spatially separated or combined can be implemented. Both variants are conceivable and among other things influenced by the planned throughput of the plant.

In 10 is another embodiment of an offset chamber 84 shown. 10a shows an arrangement in which the semifinished product 10 on a ceiling-side recording 76 is arranged and by means of the hold-down device 80 with the masking device 60 is held. Bodenseitig are fixatives 96a . 96b . 96c provided, not yet in Intervention with the half-pull 10 have been brought.

10b however, now represents a state in which the hold-down device 80 by pivoting the semi-finished product 10 has been removed. The pivoting movement about a pivot axis 100 is indicated by the numeral 102 indicated arrow illustrates. For this it is necessary that the fixative 96a . 96b . 96c the semi-finished product 10 against detachment from the recording 76 to back up. The movement is done by the with 98a . 98b and 98c indicated arrows illustrates. Now, the displacement movement of the masking 60 done analogously 9 ,

11 represents an alternative design of a deposition chamber 76 with the according to 10 on the cover side provided receptacle 76 arranged semi-finished product 10 dar. The Abscheideeinrichung 72 is arranged on the bottom side. In this arrangement, the masking agents 30 via buffering agent 104a . 104b provided and recorded in the form of filament rolls. The leadership roles 42a . 42b serve for the deflection of the masking agent and the application of a biasing force in the direction of the surface 74 of the semifinished product 10 , A biasing force in the longitudinal direction of the masking agent is provided by a tensioning means 56 in the form of a spring, attached to the leadership 42b attacks, initiated.

The masking agent is particularly advantageous 30 along its longitudinal direction relative to the semifinished product 10 a relative movement, as by the with 105a and 105b indicated arrows indicated. It can thereby effectively the deposition of material on the masking agent 30 be reduced. In particular, it may also be possible, the masking agent 30 continuously or quasi-continuously supply a cleaning device in order to remove process-related material residues and other impurities can.

In this context, add that the filaments of the masking agent 30 on the buffering agents 104a . 104b can already abut each other or individually supplied by a plurality of buffer means and only by the guide rollers and centering means are applied to each other and after passing the semifinished product 10 in turn isolated and can be wound up on separate buffering agent.

In the 12 and 13 is a flowchart for performing the method according to the invention by means of a device 106 presented in the form of a cluster or cell manufacturing plant and this process through a with 109 be indicated process arrow sequence indicated. A means of transport 108 for feeding and discharging the semi-finished products 10 . 10 ' . 10 '' is with a lock 110 coupled, which serves to decouple the process gas atmosphere or the process-side applied vacuum from the environment.

A handling chamber 122 with a handling device 124 , for example in the form of a handling robot, ensures the handling of the semi-finished product 10 ' in the device 106 , It is conceivable that in the lock 110 the hold-down device 80 with the masking device 60 , according to 6 and 7 , on the semi-finished product 10 ' is applied. Thus, the semifinished product 10 ' as in 12 represented in a first chamber 112 for the deposition of the back contact and immediately thereafter in a chamber 114 be introduced for deposition of the n-layer.

This is followed by a first offset operation, which in the offset chamber 84 is performed, which according to 7 can be configured and about, but not exclusively, with the Versatzeinrichtung 86 can be provided. Subsequently, a transfer takes place in a chamber 116 for the deposition of the i-layer, which in turn is an offset process in the displacement chamber 84 followed. This is followed by a transfer into a chamber 118 for the deposition of the p-layer and finally the transfer into a chamber 120 for the separation of the front contact.

After another pass through the lock 110 and transfer from the process gas atmosphere or the process-side adjacent vacuum in the environment, the semi-finished 110 '' , which is now provided with a solar cell assembly according to the invention, again the means of transport 108 be supplied.

semi-finished 10 with rigid carrier substrates are particularly suitable for the production of large-area solar cell arrangements, since the carrier substrates of the arrangement impart mechanical strength, whereby the production-compatible handling of larger units is made possible. With the device shown by way of example 106 for carrying out the method according to the invention can be semi-finished products 10 process with rigid carrier substrates whose base areas cover about areas of less than 0.5 m ² to greater than 5 m ² . These bases are advantageously square or rectangular, but may also have other suitable shapes.

It is understood that the inventive method further process steps before, intermediate, downstream or else can be switched to the manufacture of solar cell assemblies to complete.

This can in particular cutting and cleaning processes, the application of other active and passive components, testing and control steps as well as lamination or assembly processes. Furthermore, an antireflection coating is usually applied to the surface of such solar cells to optimize the effect of the incident light.

14 Finally, schematically represents a possible sequence of the process according to the invention, with a device according to 12 and 13 can be carried out.

Alternatively, it is conceivable, based on the steps in 14 to design a line or assembly line production, which may be advantageous for example in a planned mass production. Accordingly, according to the sequence shown, two locks 110a . 110b be provided, one of which serves for the entry and the other the exit from the process gas atmosphere or the process-related vacuum. In between are process chambers 112 . 114 . 116 . 118 and 120 arranged for the deposition of material layers, in turn, two offset chambers 84a . 84b for displacement of the masking agent 30 are interposed. The necessary transfer takes place by means of the handling device indicated here by arrows 124 ,

It is to add that also mixed forms as for example a combined line and cell production are conceivable, in particular then, if it seems possible, through expensive manufacturing facilities to use multiple lines or to buffer options to provide process security.

With The inventive method can now be based on simple and, conveniently, a serially interconnected fabrication Thin-film solar cells with rigid carrier substrates be performed. In particular, they are connected to the interconnection involved process steps in the process gas atmosphere or in a vacuum, without the structuring of the material layers necessary in this case must be provided outside of it.

By this in-situ interconnection can be expenditures for external devices such as laser cutting machines or mechanical scoring systems avoid or reduce. In addition, it improves the process quality, because now less lock operations and fewer transfers outside the process gas atmosphere or the vacuum is necessary.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - WO 2007/044555 A2 [0004]
• - WO 2007/085343 A1 [0008]

Claims (21)

Method for producing series-connected thin-film solar cells, comprising the following steps: arranging a semifinished product ( 10 ) with a rigid carrier substrate ( 12 ) on a recording ( 76 ); - introduction of the semi-finished product ( 10 ) in a deposition chamber ( 70 . 112 . 114 . 116 . 118 . 120 ) with a separating device ( 72 ); Application of a masking device ( 60 ) with at least one strand-form masking agent ( 30 ), which is biased in the longitudinal direction, on one of the separator ( 72 ) facing surface ( 74 ) of the semifinished product ( 10 ); Partial shading of the surface ( 74 ) of the semifinished product ( 10 ) by means of the masking device ( 60 ) opposite the separation device ( 72 ) for structuring a material layer to be deposited ( 14 . 16 . 18 . 20 . 22 . 24 ); - deposition of the material layer ( 14 . 16 . 18 . 20 . 22 . 24 ) on the semi-finished product ( 10 ); and - releasing the masking device ( 60 ) from the surface ( 74 ) of the semifinished product ( 10 ). The method of claim 1, wherein the strand-like Masking means a plurality of adjacent filaments having. Method according to Claim 1 or 2, in which a carrier substrate ( 12 ), which consists of a glass, a glass ceramic material, a wafer, a plastic or a metal. Method according to one of the preceding claims, in which the semifinished product ( 12 ) convex with respect to the separator ( 72 ) is arched. Method according to one of the preceding claims, in which the strand-shaped masking agent ( 30 ) during the deposition of the material layer ( 14 . 16 . 18 . 20 . 22 . 24 ) relative to the semifinished product ( 10 ) a relative movement in the longitudinal direction of the masking agent ( 30 ). Method according to one of the preceding claims, in which the strand-shaped masking agent ( 30 ) is supplied and removed continuously or quasi-continuously in the longitudinal direction. Method according to one of the preceding claims, in which the strand-shaped masking agent ( 30 ) with at least one leading role ( 42 ) or by at least one centering means ( 44 ) is aligned. Method according to one of the preceding claims, in which the strand-shaped masking agent ( 30 ) by a hold-down device ( 80 ) transversely to its longitudinal direction, substantially perpendicular to the surface ( 74 ) of the semifinished product ( 10 ) is charged. Method according to one of the preceding claims, in which the hold-down device ( 80 ) the at least one leadership role ( 42 ) or the at least one centering means ( 44 ) having. Method according to one of the preceding claims, in which the strand-shaped masking agent ( 30 ) in the longitudinal direction by a tensioning means ( 56 ), in particular a spring is biased. Method according to one of the preceding claims, in which a plurality of material layers ( 14 . 16 . 18 . 20 . 22 . 24 ) using several deposition chambers ( 70 . 112 . 114 . 116 . 118 . 120 ) on the semi-finished product ( 10 ) are deposited. Method according to one of the preceding claims, in which between the deposition of the material layers ( 14 . 16 . 18 . 20 . 22 . 24 ) the strand-shaped masking agent ( 30 ) transverse to its longitudinal direction on the surface ( 74 ) of the semifinished product ( 10 ) to contact or separate certain layers of material ( 14 . 16 . 18 . 20 . 22 . 24 ). Method according to one of the preceding claims, in which the deposition of the material layers ( 14 . 16 . 18 . 20 . 22 . 24 ) and the displacement of the strand-like masking agent ( 30 ) takes place in a process gas atmosphere or in a vacuum. Method according to one of the preceding claims, wherein the displacement of the strand-shaped masking agent ( 30 ) in a separate displacement chamber ( 84 ) he follows. Method according to one of the preceding claims, in which a transfer takes place between the deposition and the displacement, in which the semifinished product ( 10 ) is further exposed to the process gas atmosphere or the vacuum. Method according to one of the preceding claims, in which by cleaning, in particular etching processes, soiling or residues of the separated material layers ( 14 . 16 . 18 . 20 . 22 . 24 ) from the masking device ( 60 ) are removed. Device for producing serially connected thin-film solar cells with at least one deposition chamber ( 70 . 112 . 114 . 116 . 118 . 120 ) with a separating device ( 72 ), with a recording ( 76 ) for receiving a semi-finished product ( 10 ) with a rigid carrier substrate ( 12 ), in particular a carrier substrate ( 12 ) made of a glass material, and with a masking device ( 60 ) applied to the semifinished product ( 10 ) is applicable, wherein the masking device ( 60 ) a strand-shaped masking agent ( 30 ), which can be prestressed in the longitudinal direction and for partial shading of the semifinished product ( 10 ) opposite the separation device ( 72 ) relative to the semifinished product ( 10 ) is alignable. Apparatus according to claim 17, wherein the strand-like masking means comprises a plurality of filaments ( 32 . 34 . 36 ) having. Apparatus according to claim 17 or 18, wherein the receptacle ( 76 ) for receiving the semi-finished product ( 10 ) with respect to the separator ( 72 ) is convexly curved. Apparatus according to claim 17, 18 or 19, comprising a plurality of deposition chambers ( 70 . 112 . 114 . 116 . 118 . 120 ) for the deposition of the material layers ( 14 . 16 . 18 . 20 . 22 . 24 ), an offset chamber ( 84 ) with a misalignment device ( 86 ) with offset means ( 92 ) for displacing the at least one masking agent ( 30 ) transverse to its longitudinal direction relative to the surface ( 74 ) of the semifinished product ( 10 ) and a handling chamber ( 122 ) with a handling device ( 124 ) for feeding the semifinished product ( 10 ) into the chambers ( 70 . 84 . 112 . 114 . 116 . 118 . 120 . 122 ) having. Apparatus according to claim 20, wherein at the chambers ( 70 . 84 . 112 . 114 . 116 . 118 . 120 . 122 ) A vacuum can be applied or a process gas can be supplied.