TW200832732A - Roll-to-roll electroplating for photovoltaic film manufacturing - Google Patents

Abstract

A roll to roll system for forming an absorber structure for solar cells on a flexible foil as the flexible foil is advanced through units of the system and by unwrapping from a supply spool and wrapping around a take-up spool. Surface of the flexible foil is first conditioned in a conditioning unit to form an activated surface. A precursor stack including copper, gallium and indium layers is electroplated onto the activated surface by utilizing separate electroplating units for each layers. The precursor layer is reacted with at least one of Se and S in an annealing unit of the system.

Description

200832732 IX. Description of the Invention: [Technical Field] The present invention relates to a method and an apparatus for preparing a film of an IBIIIAVIA compound semiconductor film for use in a radiation detector and a photovoltaic application. [Prior Art] A solar cell is an optoelectronic device that can directly convert sunlight into electricity. The most common solar cell material is germanium in the form of single crystal or polycrystalline wafer. However, the power generated by the solar cell based on germanium is used. The cost is higher than the cost of electricity generated by more traditional methods, so since the early 1970s, efforts have been made to reduce the cost of solar cells used on land. One way to reduce the cost of solar cells is to develop low cost film growth techniques that deposit solar cell characteristic absorber materials on large area substrates and produce these devices using local yield, low cost methods. The IBIIIAVIA compound semiconductor includes materials of Group 18 (Cu, Ag, Au), Group IIIA (B, Al, Ga, Ι, τΐ) and VIA (0, S, Se, Te, Po) in the periodic table or Element, which is an excellent absorber material for thin film solar cell structures; in particular, compounds of Cu, In, Ga, Se and S (generally referred to as CIGS(S) or Cu (In 'G a)) (S, S e) 2 or Cul n 1-XG ax (S y S e 1 .y ) k, where 〇< j, 〇SySl' and k is about 2) has been applied to the solar cell structure, and It can produce nearly 20% conversion efficiency, but contains π Α Α elemental element eight! And/or the absorber of the Group VIA element Te also exhibits the same effect; therefore, overall, 'in solar cell applications' contains i) at least one of the Groups 5, 2008, 327, 32 in the Group IB, and at least one of In, Ga and A1 and iii) Among the VIA families, compounds of at least one of S, Se and Te are the most noticeable. Fig. 1 illustrates the structure of a conventional IBIIIAVIA compound photovoltaic cell (e.g., Cu(In, Ga, Al)(S, Se, Te) 2 thin film solar cell). The device 10 is fabricated on a substrate (for example, a glass plate, a metal plate (aluminum or stainless steel), an insulating box or mesh, or a conductive foil or mesh), and contains Cu (In'Ga, Al) (S, Se, Te). The absorber film 12 of one of the 2 families is grown on a conductive layer 13 which is previously deposited on the substrate 11 and serves as an electrical contact to the device. Various conductive layers including M〇, Ta, W, Ti, and stainless steel have been used in the first! The solar cell structure shown in the drawing; if the substrate itself is a suitably selected conductive material, the conductive layer 13 may not be used because the substrate u can be used as an ohmic contact to the device. After the absorber film 12 is grown, a penetrating layer 14' such as a CdS, ZnO or CdS/ZnO stack is formed on the absorber film. The light radiation 15 enters the device via the penetrating layer 14, and a metal mesh (not shown) is also deposited on the penetrating layer 14 to reduce the effective series resistance of the device. It should be noted that if the substrate is transparent, the structure shown in Figure 亦可 can also be reversed. In such an example, the light enters the device from the substrate side of the solar cell. In a thin film solar cell using the IBIIIAVIA compound absorber, the battery efficiency is related to a strong 2 function of the ΙΒ/ΠΙΑ molar ratio. If there is more than one steroidal material in the composition, the relative amount or molar ratio of these steroidal elements will also affect its properties. for

For the Cu(In,Ga)(S,Se)2 absorber layer, for example, the efficiency of the device is a function of the molar ratio of Cu/(In + Ga); in addition, the battery is different.

Parameters (such as its open circuit voltage, short circuit current, and fill factor) are also proportional to the molar ratio of Group IIIA elements (ie, Ga/(Ga+in) moles. In general, for device performance, Ga/ (Ga+In) Mo ¥ ratio is kept at about or below; on the other hand, when the Ga/(Ga+;{) molar ratio increases, the optical energy gap of the absorber layer increases, and the open circuit voltage of the solar cell Therefore, the short-circuit current is generally reduced. For the film > integral program, it is important to control the composition of the IB/ΠΙΑ group molar ratio and the molar ratio of the IIIA component. Note that although the chemical formula is often written as Cu(In,Ga)(S,Se)2, the exact chemical formula of the compound should be Cu(In,Ga)(S,Se)k' where k is generally close to 2, but not precise. For the sake of simplicity, the following continues to use a k value of 2; it should be noted that in the chemical formula, Cu(X, Y) represents X and Y respectively from (X== and γ = 100%) to (Χ=100 All chemical compositions of % and Υ = 〇%), for example, Cu(In, Ga) represents all compositions from Culn to CuGa, and similarly, Cu(In, Ga (S, Se) 2 represents a group of foods in which the Ga/(Ga+In) molar ratio is from 〇 to 1 and the Se/(Se + S) molar ratio is from 0 to 1. The first type is used for growth. The technology of the Cii (In, Ga) Se2 layer is a co-evaporation method involving the evaporation of Cu, In, Ga and Se from a single steaming boat to a heating substrate. The deposition rate of each component is careful. Monitoring and control. Another technique for growing Cu(In,Ga)(S,Se)2 type compound thin films for solar cells is a two-stage process, which first deposits Cu(In,Ga) on a substrate ( At least two components of the S, Se) 2 material are then reacted with S and/or Se in a high temperature annealing procedure; for example, for CuInSe2 growth, Cu 7 200832732

The thin sublayer with In is first deposited on a substrate to form a precursor layer, which then reacts with Se at a higher temperature, and if the reaction atmosphere is rich, CuIn(S, Se) can be grown. 2 layer. Add Ga to the precursor layer,

That is, a Cu (Iii, Ga) (S, Se) 2 absorber can be grown by using a Cu/In/Ga stacked film precursor. Other prior art involves depositing a Cu-Se/In-Se, Cu-Se/Ga-Se or Cu-Se/In-Se/Ga-Se stack and reacting it to form a compound. It is also possible to use a mixed precursor stack comprising a compound and an elemental sublayer, such as a Cu/In-Se stack or a Cu/In_Se/Ga-Se stack, wherein In-Se and Ga-Se represent selenides of In and Ga, respectively. Sputtering and evaporation techniques have also been used in the prior art to deposit sublayers containing bismuth IB and bismuth components of the metal clumps; for example, in the case of CuInSe2 growth, sequentially on the substrate The Cu and In sublayers are deposited from the ClI and in targets by sputtering, and then the resulting stacked precursor film is heated at a higher temperature in the presence of a gas, as described in U.S. Patent 4,798,660. In recent years, U.S. Patent No. 6,48,442 discloses a method of electroplating a stacked precursor film to form a Cu-Ga/In stack on a metal counter electrode, the precursor film comprising a Cu_Ga alloy sublayer. And the In sublayer, and then reacting the precursor stack film with one of the s to form a compound absorber layer. U.S. Patent No. 6,92,669 describes an apparatus and method for producing such an absorber layer based on sputtering. A method is described in U.S. Patent No. 4,581,108, which is incorporated herein by reference. In this method, a Cu sublayer is first electrodeposited on the plate, followed by electrodeposition of a ϊn sublayer, and heating of the deposited Cu/In precursor stack in a reaction atmosphere containing s 200832732. High plate current density, which causes non-uniformities and problems with substrate bonding, as described in the reference (Kapur et al., "Low cost Thin Film Chalcopyrite Solar Cells 9% Proceedings of 18th IEEE Photovoltaic Specialists Conf., 1985, p. 1429". "Low cost Methods for the Production of Semiconductor Films for CIS/CdS Solar Cells'', Solar Cells, vol. 21, p. 65, 1987)

Described. The above brief review illustrates the current need to develop high-volume, low-cost technologies for the manufacture of thin-film solar cells and modules. SUMMARY OF THE INVENTION The present invention provides a winding system for forming a solar cell absorber that continuously treats the surface of the flexible foil as the flexible foil advances through the processing unit of the roll-up system. SUMMARY OF THE INVENTION One idea of the present invention is to provide a system for forming a solar cell 1 < absorber structure that forms an absorption on the front surface of a continuous flexible workpiece as the continuous flexible workpiece advances through the unit of the gold w, the system Body Sowing. The system includes a conditioning unit to condition the front surface of the continuous flexible workpiece to form an activated surface portion. The system further includes a first plating unit for forming a first layer of one of the < t ^ precursor stacks, wherein the continuous flexible workpiece advances through the 兮 chain and the first plating unit by The activation tables of the continuous flexible workpiece are formed by electroplating a metal, wherein the metal belongs to one of the ΐ ΐ 族 族 and the ninth 200832732 周期 family on the periodic table. a first cleaning unit of the system for cleaning the first layer deposited in the first electron microscope unit. The system further includes a second plating unit for forming a second layer of the precursor stack, As the continuous flexible workpiece advances through the second plating unit and the first layer is continuously plated in the first plating unit to the next active surface portion of the continuous flexible workpiece surface, by A metal is formed on the first layer, wherein the other metal belongs to one of the third and third groups of the periodic table, and the first layer is different from the second layer. A second cleaning unit of the system is for cleaning the second layer deposited in the second electroplating unit. The system further includes a third plating unit for forming a third layer that advances through the first, second, and third money units while the second layer is attached to the second layer Electroplating unit is continuously plated to the first layer (which is next to the active portion of the flexible workpiece surface by the electric clock) and the first layer is continuously plated in the first first plating unit at the flexible When the active portion is under the surface of the workpiece, the precursor is stacked by electroplating a metal belonging to one of the first and third groups to the second layer. The third layer is different from the first and second layers. The system also includes a moving assembly for holding and linearly moving the unit of the continuous flexible workpiece through the system, wherein the moving assembly includes a feed feed spool and a pick-up spool for unwinding and providing the continuous The unprocessed portion of the workpiece is flexibly threaded into the system, and the pick-up spool is used to receive and wind the processed portion. [Embodiment] 10

200832732 The present invention provides a low cost, high throughput two segment for the manufacture of CIGS (S) type absorption for solar cells. Figure 2 is a schematic illustration of the program and tool of the present invention; in this embodiment, Using a winding process, the workpiece 22 (for example, having a flexible substrate and a contact layer can be electrodeposited with a Group IB material (preferably Cu) and a first (more than In and Ga at least) a) a tool 9 having a shaft 20 and a return spool 21, the flexible foil substrate 22 being guided from a series of plating units 23 to the return spool 21 23 comprising at least one Group IB material plating unit and at least A material plating unit; after each plating unit 23, preferred units 24A, 24B. After each plating process, the wet plating surfaces, and thus the cross-contamination of the electroplating electro-fluid in the plating unit 23 is avoided. After electrocoating a section of the substrate 22 in a plating unit, the section passes - wherein the chemical residue of the Cu bath on the section is moved by the section to the third group plating Unit (such as Ga. should pay attention to The zone can also be dried after the wetting step. Generally, the surface of the plated material remains wet when it enters another plating solution. A unitary 25 is required at the end of the tool 19 to ensure that the iB group containing the plating is provided. In contrast to the Group IIIA foil substrate 22, before it is wound onto the recovery reel 21, it is dried*»to avoid damage to the plating layer, and can be fed from the packaging reel 27 to the recovery reel 21 containing the electroplated Group IB material program. The g-layer is embodied in a continuous flexible foil substrate. The 111A family material has a supply roll supply reel 20. The treatment unit is a genus with a clean cleaning unit repellent or electroplated Cu plating or • cleaning unit, washing And then electroplating unit); however, it is preferred to make the wet/dry single material flexible* fully cleaned and dry into a packaging board with the Dai family

II 200832732 Between the layers of the flexible foil substrate 22 of the material' wherein the packaging sheet 26 can be a paper or thin polymeric sheet. The flowchart 100 shown in Figure 5 provides an exemplary program flow for a particular embodiment of the roll-to-roll system of the present invention. Initially, as shown in block 1 〇 1, a contact layer can be formed on the substrate to form a continuous wrapable workpiece on which the system of the present invention is constructed using the system of the present invention. Next, as shown in block 102, in a surface activation step, the surface of the contact layer is conditioned to form an activated surface for subsequent electrodeposition procedures. As shown in block 103, the surface of the conditioned contact layer is cleaned prior to electrodeposition, e.g., wetted with a cleaning solution to remove possible chemical residues and particles from the surface of the contact layer. It should be noted that the surface activation step is very important because the electrodeposition efficiency on the surface depends on the nature of the material deposited on the surface, and the activation surface is an electrochemically active material surface, which is efficient. Electroplating is performed; if the surface exhibits electro-chemical inertness, the electrodeposition efficiency is generally low and the bondability is poor. However, the 'electron' efficiency on a surface that is active or activated will be higher and more consistent; consistent electrodeposition will result in uniform thickness of the electrodeposited material. In the present invention, the cms-type absorber layer is formed by using a precursor stack (for example, Cu/Ga/In or stack). 'The thickness of these layers in the stack needs to be tightly controlled to further (4) Cu/(In+Gam Ga/ The ratio of (In + Ga) is generally less than 1, which is very important for the quality of the resulting absorber and the performance of the solar cell fabricated on such an absorber. The general target ratio of cu/(In+Ga) In the range of 0·"·95; in the wound system, a first layer (such as a Cu layer) is deposited on the contact layer of 12 200832732. The contact layer is different. The length of time is exposed to the atmosphere, and the end thereof Depending on the position of the reel. For example, if the flexible workpiece moves at 2 ft/min, in a 5000 ft long reel, the contact layer at the beginning of the roller is coated with copper within a few minutes. The contact layer at the end of the reel is coated after 41 hours; the change in exposure time of the contact layer will cause contact layer conditioning differences due to oxidation, exposure to chemical fumes, etc. The plating rate of the Cu layer on the layer will be due to its At the beginning and at the end of the spool is different 'Xin this rate difference may then result in different overall thickness of the Cu layer flexible workpiece, and cause

The Cu/(In+Ga) molar ratio is changed, thus reducing the process yield, and it is impossible to manufacture a high-efficiency solar cell with high yield. By electrodepositing the first layer on the contact layer, it is ensured that the electrodeposition efficiency of the first layer on the contact layer is uniform throughout the reel by using the activation chamber and the activation procedure step, and that uniformity is ensured. The ratio of Cu/(In+Ga). When a subsequent electroplating procedure is performed to plate a first metal layer (e.g., steel onto an activated surface, the conditioning process of the present invention results in a 90% increase in heart rate; for example, by an anionic conditioning procedure The activated surface formed on the contact layer can be used for subsequent plating procedures (such as copper plating) with a plating efficiency of 90%. However, if the surface is electrochemically inert, the efficiency of the electrical reference is lowered and low. 90%, or even as low as 20-50%. Blocks 104 to 108 illustrate the sequence of programs used to form the stack of precursors prior to the month of the present invention. As shown in block 104, in a first electrodeposition step, A Group IB material (eg, copper) can be electrodeposited on the surface of the conditioned and cleaned contact layer. After this step, a cleaning step is performed to clean the electrodeposition of the 13th 200832.

The surface of the IB material is shown in Figure 1-5. As shown in block 106, in a second electrodeposition step, a first Group IIIA material (e.g., gallium) is deposited on the surface of the cleaned Group IB material layer, and after this step, a cleaning is performed. The procedure is to clean the surface of the electrodeposited first layer of the lanthanum material as indicated by block 107. As in block 108, a second Group IIIA material (e.g., indium) is electrodeposited on the surface of the cleaned first lanthanum material layer in a third electrodeposition step to complete the precursor stack. The precursor stack is cleaned and dried in the next step, as in block 109; the precursor stack is reacted in the presence of a Group VIA material (eg, selenium and sulfur transported in the vapor phase) to form an absorption. Body, as shown in block 110. Alternatively, only the precursor layer in block 108 is cleaned without drying, as shown in block 111, to electrodeposit a Group VIA material onto the precursor stack as indicated by block 112. After the electrodeposition process, the precursor stack with the VIA material layer is cleaned, as in block 113, dare to form an absorber, such as block 114. Other Group VIA materials may be introduced as needed during the reaction to form an absorbent body. The winding-up procedure of the present invention provides several advantages. Electrodeposition is a process with high sensitivity to the surface. Most of the defects in the plating layer come from the surface of the clock; therefore, it is best to minimize the substrate processing in the plating process. Substantial contact, particles, etc., cause defects in the subsequent deposition of the film on the surface. The plating efficiency and thickness uniformity of the plating layer are also affected by the conditions of the surface to be plated, for example, by electrodeposition on a surface exposed to air, a chemical gas, or a general external environment for different times. A chemically active, freshly deposited electrode of Cu, Ga or In on the surface of 200832732 is a more reproducible procedure. In the wind-up procedure, all deposits are done in a controlled environment (details on the roll are not shown in the figure) and the time between deposits is minimized 'unlike several loads required in the batch program And an unloading step to deposit a stack of materials on the _ substrate. In the winding procedure of the present invention, a material (e.g., copper) is formed on a section of the substrate; after the clocking and washing step, the surface of the material is fresh and active, Thus, when the segment is moved into the next bath (e.g., Ga or In bath) in seconds or minutes, deposition begins on the active surface. If the rate of the foil substrate is fixed, then Ga or In plating will always operate on the same active Cu surface'. This will result in a high degree of repeatability in the thickness and uniformity of the layers of ιη and Ga, for the case of the Cu layer. is also like this. If a Cu layer is deposited on the flexible substrate, the surface of the flexible foil substrate can be first obtained by passing the flexible foil substrate through a pre-deposited electrolyte and applying a pre-deposition treatment step or conditioning the surface. activation. The pre-deposition treatment step may be an etching step or an electro-treatment step such as an anionic conditioning step or a cationic conditioning step, wherein the anion conditioning step comprises: • applying a cathode to the substrate relative to the electrode in the pre-deposited electrolyte The cation conditioning step includes applying a voltage to the substrate that is anodic relative to the electrode in the pre-deposited electrolyte. The conditioning step can also include an acid pickling step; or include depositing on the substrate prior to Cu deposition. A deposition step of a fresh layer; in these examples, an active surface can be provided for the Cu electrodeposition step such that this step produces repeatable results in the thickness and uniformity of the Cu layer. As described above, for deposition of Cu, iη and/or 15 200832732

The thickness and uniformity control of the Ga layer is of high importance because it is necessary to control the Cu/(In+Ga) and Ga/(In + Ga) molar ratios of the matrix as a whole. FIG. 3 shows an exemplary The roll-up plating system 3 制造 can manufacture a metal stack including Cu, In and Ga on a flexible substrate 22 with high thickness controllability and uniformity. The electroplating system 3A includes a series of units, a supply spool 20, a return spool 21, and a mechanism for guiding the flexible foil substrate 22 from the supply spool 2 to the recovery spool 2 1 via the series of processing units (not shown) . The series of processing units includes at least one electroplated single το 31, at least one Ga plating unit 32, and at least one a plating unit 33; it should be noted that the order of the plating units can be varied to achieve different stacks on the substrate. For example, the order of the plating units shown in Figure 3 will create a Cu/Ga/In stack on the substrate, changing this order and adding other plating units as needed to obtain Cu/In/Ga, In/Cu/ Stacking of Ga, Ga/Cu/In, Cu/Ga/Cu/In, Cu/Ga/Cu/In/Cu, Cu/In/Cu/Ga, Cu/In/Cu/Ga/Cu, etc. Repeat to produce more such stacks. However, stacking starting with a Cu layer is preferred because cu plating can produce a highly controllable, metallographically good coating with high clocking efficiency, and Cu is comparable to Ga or In plated thereon. Good substrate. Hereinafter, the present invention will be described using the configuration shown in Fig. 3, in which the plating system 30 includes one of a Cu plating unit, a Ga plating unit, and an in plating unit. In the electroplating system 30 of Fig. 3, it is preferred to have a conditioning unit 34' which conditioned the surface of the flexible foil substrate 22, while the Cu layer will be on the Cu electric clock 16 200832732

The unit 31 is electroplated on the surface. 3A illustrates the general structure of a flexible foil substrate 22 that includes a flexible foil substrate 45 in contact with a conductive layer 46 or a first surface 45A deposited on the flexible foil substrate 45. Zhan. The rewritable f|substrate 45 can be made of any polymer or metal pig, but is preferably a metal foil, such as a 20-25 Ομη thick stainless steel foil, a Ti, a Α1 foil or an aluminum alloy foil; various metal foil substrates (eg Cu, Ti, Mo, Ni, A1) solar cells that have been proven to be usable in CIGS(S) (eg BM Basol et al. "Status of flexible CIS research at ISET", NASA Document ID: 19950014096, accession Ν〇·: 95Ν-20512, data from NASA Center for Aerospace Information. The conductive layer 46 may be in the form of a single film layer, or may comprise a stack of various sub-layers (not shown); preferably, conducting The layer includes at least one diffusion barrier layer that prevents impurities from diffusing from the flexible foil substrate 45 to the film layer to be electrodeposited and into the CIGS(S) layer during its formation. The material of the conductive layer 46 includes, but is not limited to, Ti, Mo, Cr, Ta, W, Ru, Ir, Os, and nitrides and oxynitrides of these materials are preferably 'the free surface 46A of the conductive layer 46 includes at least one of Ru, Ir, and Os to provide The plating layer is better for tuberculosis. In an example, electrodeposition is performed on the free surface 46A of the conductive layer 46, and an auxiliary layer 47 (indicated by a broken line) may be coated on the rear surface 45B of the flexible foil substrate 45 as needed to protect during the annealing/reaction step. The foil substrate 45 is flexed to form a CIGS (S) compound, or the flexible foil substrate 45 is prevented from being bent; it is important that the material of the auxiliary layer 47 is stable in Cn, In, and Ga plating chemistry, that is, in these plating solutions. Will not dissolve or not on it 17 200832732

Contaminants' can avoid reaction with Group VIA materials; materials that can be used in the auxiliary layer 47 include, but are not limited to, Ru, Os, Ir, Ta, W, and the like. The use of an auxiliary layer 47 comprising at least one of Ru, Ir and Os has the additional advantage that this material is highly resistant to the reaction of Se, S and Te; therefore, any layer forming a CIGS(S) compound is free on the conductive layer 46. After the reaction step on surface 46 A, the auxiliary layer protects the flexible foil substrate 45 from reacting with .Se, S or Te and leaving a surface that can be easily soldered. In a conventional device, Mo may serve as the auxiliary layer 47; during the selenization and/or vulcanization treatment, or during the growth of the CIGS (S) absorber, the Mo layer reacts with Se and/or S to form a Mo ( S, Se) surface layer. After the solar cells are completed, they need to be interconnected to form a module; the interconnection includes soldering or attaching the back surface of each cell to the front surface of an adjacent cell. The Mo(S,Se) layer behind the battery cannot be effectively soldered, so the surface of the selenized and/or vulcanized Mo needs to be substantially removed; however, the surface including one of Ru, Ir and Os can be easily soldered, There is no need to remove the additional steps of selenizing or vulcanizing the surface layer because these materials are not selenized or vulcanized. Referring to Fig. 3, before entering the Cu plating unit 31, the flexible foil substrate 22 passes through a conditioning unit 34 and passes through a cleaning unit 35 as needed. In the conditioning unit 34, the surface of the flexible foil substrate 22 (e.g., the free surface 46A of the conductive layer 46 in Figure 3A) is conditioned to prepare for Cu plating. The conditioning procedure includes exposing the free surface 46A to an acidic or alkaline solution for etching and/or activation, applying a cathode or anode to the free surface 46A relative to the electrode when both the electrode and the free surface 46A are exposed to an electrolyte. a voltage, electrodepositing a crystal 18 on the free surface 46A 200832732

The layer, or only the free surface 46A, is wetted before it is moved to the Cu plating unit 31. If only the wetting procedure is performed in the conditioning unit 34, the cleaning unit 35 is not required; otherwise it is necessary to remove any remaining on the surface of the flexible foil substrate 22 with the cleaning unit 35 before moving it to the Cu plating unit 31. Residual chemicals. In the present invention, if a crystal layer is electrodeposited on the free surface 46A in the conditioning unit 34, the crystal layer may be a Cu layer having a thickness of 2-50 nm, and it may be deposited from a plating solution. It produces a uniform film layer free of defects; a miscible Cu electrolyte with a high pH is particularly suitable for this purpose. The bismuth seed layer and various chemical substances used for electroplating are disclosed in the US patent filed on November 2, 2005, entitled "Technology and Equipment for Deposition of Semiconductor Layers of Solar Cells and Module Manufacturing". U.S. Patent Application Serial No. 1 1/462,685, the entire disclosure of which is incorporated herein by reference. The entire contents of these applications are incorporated herein by reference. Once a section of the free surface 46A of the conductive layer 46 is conditioned and cleaned, it moves into the Cu plating unit 31. Within the Cu plating unit 31, the free surface 46A ( Or if the surface of the seed layer when the seeding layer has been deposited by the conditioning unit 34 is exposed to the copper plating solution 36A which is circulated between a first storage tank 3 6AA and a first chemical tank 36A'; during the cycle Or in the first chemical tank 36A', the copper plating solution 36A can be filtered and supplemented. In the first chemical tank 3 6 A', different plating liquid parameters can be controlled continuously or periodically, for example: additive content, Copper content Temperature, pH, etc., to ensure the stability of the copper deposition process. The conductive layer 19 200832732 46 can be achieved in different ways (or when the flexible foil substrate itself is conductive, ie to the flexible foil substrate 45) Electrically connected, including via a roller 39 that is in contact with at least a portion of the front and rear surfaces thereof with the flexible foil substrate 22, preferably, a front surface contact is made at both edges that avoids substantial contact with most of the front surface, In order to avoid damage or contamination of the surface by contact, a first anode electrode 40 A is placed in the copper plating solution 36A, and a bit is applied between the first anode electrode 40A and the partial conductive layer 46 in the steel plating unit 31. Poorly, when the flexible foil 22 moves, Cu is deposited on a portion of the free surface 46A exposed to the copper plating solution 36A. The flexible pig matrix 22 treated in the Cu plating unit 31 is passed through Cu. The cleaning unit 37A is inserted into the Ga plating unit 32. In the (5) electroplating sheet 7G, the surface of the deposited Cu layer is exposed to a Ga plating solution 36 which is circulated in a second storage tank 36BB and a second chemical tank. During the cycle or in the first The second chemical tank 36B can filter and supplement the Ga clock liquid 36B. The second chemical tank 36b can continuously or periodically control different plating liquid parameters, for example, the additive content 'Ga content, temperature , pH, etc., to ensure the stability of the Ga deposition process. The electrical properties of the conductive layer 46 (or when the conductive substrate itself is conductive, ie, the flexible substrate 45) can be achieved in different ways. The connection includes passing through a roller 39 that contacts at least a portion of the front and rear surfaces of the flexible substrate 22. Preferably, a front surface contact is made at both edges that avoids substantial contact with most of the front surface to avoid contact And destroy or contaminate the front surface. A second anode electrode 4〇B is placed in the Ga plating solution 36B, and a potential difference is applied between the second anode electrode 4〇b and the partial conductive layer 46 in the Ga plating unit 32. When the flexible foil substrate 22 is moved, Ga is deposited on the surface of the portion cu exposed to the electric clock liquid 36B. The flexible foil substrate portion processed in the Ga plating unit 32 passes through the Ga cleaning unit 37B and enters the in plating unit 33. In the In plating unit, the surface of the deposited Ga layer is exposed to an In plating solution 36C which is circulated between a third storage tank 36CC and a third chemical tank 36C; during the cycle or in the third chemical tank 36C. In time, the plating solution 36c can be filtered and replenished in the third chemical tank 36C, and different plating liquid parameters such as additive content, In content, temperature, pH value, etc. can be continuously or periodically controlled to ensure The stability of the In deposition program. The electrical connection to the conductive layer 46 (or to the flexible foil substrate 45 when the flexible foil substrate itself is conductive) can be achieved in different ways, including by contacting at least the flexible foil substrate 22 with at least Part of the front and rear surface of the drum 39. Preferably, the front surface contact is made at both edges to avoid substantial contact with most of the front surface to prevent damage or contamination of the front surface by contact. A third anode electrode 40 C is placed in the In plating solution 36, c, and a potential difference is applied between the third anode electrode 40C and the partial conductive layer 46 in the In plating unit 33 for the flexible foil substrate. When moving 22, In is deposited on the surface of the portion Ga which is exposed to the ITO plating solution 36C. After the in electrodeposition, a portion of the flexible foil substrate including all of the plated Cu/Ga/In stack passes through a cleaning/drying unit 38 and is moved to the recovery spool 21. It should be noted that other processing units may be added to the plating system 30 of FIG. 3; for example, another Cu electric clock unit and another cleaning unit may be added between the Ga cleaning unit 37B and the In electric boat unit 33, Manufacturing 21 200832732

Cu/Ga/Cu/In stacking. The anode electrode used in the electroplating unit may be an inert anode or it may be a Cu, E electrode and in electrodeposition containing Cu, In and Ga, respectively, a soluble anode 1 in the stack cu, In and a layer The thickness is between 10 nm and 500 nm. The details of the cleaning or cleaning/drying unit are not shown in Figure 3, however, an established cleaning device (such as a device that sprays the cleaning solution onto the portion to be cleaned or dipped into the cleaning solution) is available. In these units, an air fork that directs high velocity air or inert gas to the portion to be dried can be used as a dry climb, and the dry gas can be pre-filtered and heated to make drying more efficient and faster. An example of a roll-type electrodeposition system and method for stacking a Group IB material and a Group mA material is now described, and other processing units may be added to the plating system of Figure 3 to extend its function, as follows Said. Figure 4 illustrates a wound processing system 5A comprising an IB-ΠΙΑ family plating unit 51 and a Group VIA material plating unit IB-ΠΙΑ plating unit 51 for electrically converting the Group IB material and the Ιπν family material This builds up on the flexible foil substrate 22 to form a metal precursor film, and may include all or most of the components of the electroplating system 3, such as shown in FIG. For example, the Group IB-IIIA plating unit 51 can be deposited. Layer +, and may include the conditioning unit 34 of FIG. 3, the cleaning unit 35, (the plating unit 31, the Cu cleaning unit 37A, the Ga plating unit 32, the cleaning unit 37B, and the plating unit 33. Another can also be used The cleaning unit has a drying unit instead of the cleaning/drying unit 38 of Fig. 3, so that the changeable substrate 22 coated or electrochemically coated with cu,...in has -clean and Tan Run 22

The surface of 200832732 is moved to the VIA material plating unit 62. In the Vth group material electro-recording unit 62, at least one layer (Se layer) of Se, u is deposited on the metal precursor film, and has a "metal precursor / VIA material" stack rewritable The substrate will then pass through the final cleaning/drying module 63 and onto the recovery spool 21. The presence of a vis group material on a metal precursor film comprising Cu, (5) and In has some advantages; the advantage is that the VIA family material provides protection to the surface of the metal precursor film. 'Indium and gallium are soft, low melting materials, Moreover, it is easy to be damaged during the winding process. By depositing a layer VIA material (such as Se) on the metal precursor film, the damage property can be reduced or even eliminated, and the flexible mesh can be safely Winding onto the return spool 21. The thickness of the Group VIA material is in the range of 10_2 〇〇〇 nm. The winding treatment system of Fig. 4 may be equipped with an annealing unit 64 as shown in Fig. 4; in use, the annealing unit 64 reacts between the electrodeposited metal precursor film and the electrodeposited Group VIA material. And forming a reactive precursor layer on the flexible y# substrate 22. If the via material is Se, the reaction precursor layer contains, for example, Cu, In, Ga, Cu_(ja,

Cu-In, In-Ga, Cu-Se, In-Se, Ga-Se, Cu_In_Se, cu_Ga-Se,

The In-Ga-Se and Cu-In-Ga-Se phases are depending on the temperature applied to the annealing unit 64 and the time spent in the annealing unit 64. The temperature applied by the annealing unit is in the range of 〇〇-55 (TC, preferably in the range of 200-45 (TC). After the annealing unit 64 is present, the flexible foil containing the reaction precursor layer It will be safely wound onto the recovery reel 21, or it can be wound as shown in Figure 2. It should be noted that the VIA material plating sheet 23 200832732 62 is similar to the plating unit shown in Figure 3, the annealing unit 64. Similar to the design described in the U.S. Patent Application Serial No. The content is incorporated herein by reference. The above examples use a flexible foil substrate such as illustrated in Figure 3A.

22, the conductive layer 46 and optionally the auxiliary layer 47 may be deposited on the flexible foil substrate 45 by various deposition techniques, such as by evaporation and sputtering in a separate system, but other plating may be integrated. Or an electroless plating module in the system shown in Figures 3 and 4, before moving the flexible foil substrate 45 to at least one conductive layer before moving to other processing units (e.g., Group IB-IIIA plating unit of Figure 4) Or the contact layer and the auxiliary layer are simultaneously plated; this method causes defects in the electroplated Cu, In and Ga layers because defects (such as scratches, pinholes or other defects) in or on the contact layer are due to the contact layer. It is freshly deposited and then coated with Cu to avoid it with Ga. The contact layer in this manner needs to include a material that can be plated or electrolessly plated, and the material needs to be simultaneously applied to the CIGS(S) material i ώ t ^ 0

Bamboo needles are good ohmic choices and do not react with S and / or Se. These membranes are intercalated and disclosed in the United States, which was filed on November 2, 2005, and entitled "Deposition of Solar <& ^ and Semiconductor Layer Technology and Equipment Manufacturing of Miso Battery" , gentleman, four-seeking application No. 1 1/266,013 and August 4, 2004 application, 韶 韶 r & continued as "Technology and Reconstruction for the Preparation of Precursor Films in Thin Film Solar Cell Manufacturing" U.S. Patent Application Serial No. 11/462,685, the entire disclosure of which is incorporated herein by reference. It should be noted that by exposing the back side of the flexible foil substrate to contact with the plating solution and depositing 24200832732 current, it is possible to electrify an auxiliary layer on the back side of the substrate when the front surface is in contact with the layer. In a two-stage technique involving the deposition of a metal precursor containing Cix, yttrium and Ga and the reaction of the metal precursor film layer with at least one of S e and S, it is necessary to control the Cu, In and 〇 & Individual thickness, because it determines the final metering composition of the compound layer after the reaction step. The coiled deposition method of the present invention provides intelligent program control, so the in situ measurement device (for example, XRF) can be used to monitor these thicknesses; xrf can be probed The needles are placed at different locations in the systems shown in Figures 2, 3 and 4, which monitor the thickness of the deposited Cu, In and Ga, and optionally the Se layer. If there is a deviation between the target and the deposited thickness of any of the Cu, In, and Ga layers, the XRF tool sends a signal to the power supply that controls the thickness to increase or decrease the plating current density to maintain the film thickness at a target. Inside the window. These methods are described in detail in U.S. Provisional Patent Application No. 60/744,252, filed on Apr. 4, 2006, the entire disclosure of which is incorporated herein by reference.

Once the metal precursor film of the present invention, or the "metal precursor / Group VIA material" stack, or the reactive precursor layer is formed, the reaction or further reaction of these layers with the via material can be achieved by various mechanisms; In contrast, these layers are exposed to Group VIA gases at higher temperatures, and such techniques are well known in the art and include the presence of at least one of Se gas, s gas, and Te gas, The layers are heated to 350-600 ° C for 5 minutes to 1 hour, wherein the Se gas, the S gas and the Te gas are, for example, solid Se, solid S, solid Te, H 2 Se gas, H 2 S 25

200832732 Gas and other sources provided. In another embodiment, one or more layers of Group VIA material are deposited on a metal precursor and then heated in a furnace or thermal annealing furnace. The Group VIA material can be plated, sputtered or plated onto a metal precursor layer in a separate processing unit. Alternatively, an ink of Group VIA nai particles may be prepared and then deposited on the metal layer to form a Group VIA layer containing Group VIA nai particles, which may be immersed, sprayed, or knives. Forming or ink writing techniques deposit these layers. The reaction can be carried out at a higher temperature for 1 to 30 minutes depending on the reaction temperature; the reaction results in the formation of the IBIIIAVIA compound. It should be noted that these reaction chambers may be added to the apparatus shown in FIG. 4 or the annealing unit 64 may be a reaction unit for performing an overall in-line procedure, and the flexible foil substrate having the CIGS(S) may be wound onto the recovery reel 21 at In the above examples, a system having a horizontal mesh pattern is described. Note that the concept of the present invention can also be applied to a system in which the flexible foil substrate is operated at any angle between the vertical position and the horizontal plane. The horizontal deposition can be performed by "upward deposition" or "downward deposition". The flexible foil substrate can be moved from left to right, and vice versa, it can also be moved in a continuous or stepwise manner, or it can oscillate. The "front and rear" motion shifts when a flexible foil substrate is moved in one direction to deposit a portion of the layer thereon, and more layers are deposited as it moves in the opposite direction. DC, AC, pulsed back-pulse power supplies, or other types of supplies can be used in the deposition step. Solar cells can be fabricated on the IBIIIAVIA compound layer of the present invention using materials and methods well known in the art. For example, the layer is quickly vaporized with the first precursor material to ‘clock, trinization, this table, should be online or renewable. Then or in the first place, 26

200832732 A thin window of CdS is deposited on the surface of the compound layer by chemical immersion plating, a transparent window is deposited on the CdS layer by MOCVD or sputtering, and a metal finger pattern is deposited on the ZnO as needed. Solar battery. Although the invention has been described in terms of specific preferred embodiments, those skilled in the art can understand other modifications. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a cross-sectional view of a solar cell using an IBIIIAVIA family absorber layer; Fig. 2 illustrates a wound electrodeposition system of the present invention; and Fig. 3 illustrates another winding of the present invention Electrodeposition system, including multiple plating unit and cleaning unit; Figure 3A illustrates the structure of the flexible foil substrate; Figure 4 illustrates a winding system including an additional processing unit, including a Group VIA material plating The unit; and Figure 5 illustrate a detailed implementation flow diagram of the procedure for using a roll-to-roll system. (<1 ZnO Completion) The main component symbol description 10 Device 12 Absorber film 14 Penetration layer 19 Tool 11 Substrate 13 Conduction layer 15 Radiation 20 Supply reel 27 200832732

21 Rewinding reel 22 Flexible foil substrate 23 Plating unit 24A, 24B Cleaning unit 25 Wetting/drying unit 26 Packaging board 27 Packaging reel 30 Plating system 31 Plating unit 32 Plating unit 33 Plating unit 3 4 Conditioning unit 35 Cleaning unit 3 6A Plating solution 36AA first_slot 36A9 first chemical tank 36B plating solution 36BB second storage tank 36B9 second chemical tank 3 6C plating solution 36CC third storage tank 36C5 chemical tank 37A cleaning unit 37B cleaning unit 38 cleaning/drying unit 39 reel 40A first anode electrode 40B second anode electrode 40C third anode electrode 45 flexible foil substrate 45A first surface 45B second surface 46 conductive layer 46A white surface 47 auxiliary layer 50 wound processing system 51 plating unit 62 plating unit 63 Cleaning/drying module 64 annealing unit 101~114 step 28

Claims (1)

200832732 X. Patent application garden: i.- A system 30 for forming a solar cell-absorbent structure on the front surface of a continuous slingable member, the continuous flexible workpiece system advancing through the system Units, the system comprising: a conditioning unit for conditioning the front surface of the continuous flexible workpiece of the z 揸嫉 榼哎 edge to form a number of activated surface portions, wherein the stems. The main surface of the main v t _ /, T is activated along the continuous flexible material for electroplating. Pit the workpiece to create a uniform activation surface; a first plating unit for forming a first layer of a precursor stack when the continuous flexible workpiece advances through the first plating unit Forming a metal belonging to one of the third group and the group IIIA on the activating surface portions of the continuous flexible workpiece; a first cleaning unit for cleaning deposition in the first plating unit The first layer, a second plating unit 'for forming a second layer of the precursor stack, is when the continuous flexible workpiece advances through the second plating unit and the first layer is attached to the When the first electric clock unit is continuously plated to an active surface portion of the continuous flexible workpiece, by forming another metal electric clock belonging to the third and third groups on the first layer, wherein The first layer is different from the second layer; a second cleaning unit for cleaning the second layer deposited in the second plating unit; and a moving component for holding and linearly moving the continuous exchangeable Workpiece passing 29 2008327 32 The pick-up reel of the system processes the portion to the processing portion. 2. The application unit is configured to obtain a second layer by using the first two electroplating unit to activate the portion and the continuous flexible portion belongs to the second layer. 3. If the unit is cleaned and dried in the plating unit / 4. such as Shen Yuan, to make the units, wherein the moving assembly includes a feeding reel and a feeding reel can be unfolded and fed the continuous In the system of scratching the workpiece, the pick-up reel is used to receive and wind the system of claim 1 of the patent scope, and further comprises a third electroplating to form a third layer, which is when the continuous flexible workpiece Advancing, second and third plating units, and wherein the second layer is continuously plated to the surface of the continuous flexible workpiece, the first layer is continuously electroplated to the workpiece in the first plating unit When the surface of the surface is further activating the surface portion, the precursor is stacked by electroplating another metal of one of the lanthanum and the third group, wherein the third layer is related to the first and the patent scope The system of item 2 further includes one of a cleaning-drying three cleaning unit for cleaning the third layer, and the third cleaning unit for cleaning the third layer deposited in the third layer. Please refer to the system of the third item of the patent scope, including the annealing of the first, second and third layers. 30 200832732 5. The system of claim 3, further comprising a fourth electric clock unit for depositing a fourth layer of the VIA material on the third layer. The system of item 5, wherein the Group VI material comprises one of: Se, S, and Te. 7. The system of claim 5, further comprising a cleaning-drying unit and an annealing unit, wherein the cleaning-drying unit is for cleaning and drying the fourth layer, the annealing unit is for making the first The second, third and fourth layers react. 8. The punching system of claim 1, wherein the conditioning unit comprises at least one of: an electrical processing chamber having an electrical treatment solution and an electrode that is anionizable with respect to the continuous flexible workpiece system The cation is polarized to form the activating portions; a deposition chamber and a pickling chamber for depositing a seed layer on the front surface of the continuous flexible workpiece, and the pickling chamber Forming the front surface of the continuous flexible workpiece to form the activated portions; and an etch chamber for etching the front surface of the continuous flexible workpiece to form the activated portions. 31 200832732 9. The system of claim 1, wherein the material of the Group IB comprises copper, and wherein the first material of the first group includes Ga and In. 10 of the patent application. The system further includes a package supply spool for providing a continuous wrap sheet for placement on the processed portion as the continuous flexible workpiece is wrapped along the pick-up spool. 11. The system of claim 9, further comprising a deposition monitoring unit for monitoring and controlling the thickness of the deposited first, second and third layers. 1 2. The system of claim 11, wherein the deposition monitoring unit provides a feedback signal to each of the first, second, and third plating units to cause the first, second, and third depositions The thickness of the layer tends to a predetermined thickness of one of the first, second and third layers. 1 3. The system of claim 12, wherein the trend is for maintaining a target ratio of Cu/In+Ga to Ga/In+Ga. 14. A method of forming a precursor stack on a front side of a continuous flexible workpiece using a system comprising a moving component, wherein the front side package 32 200832732 includes a conductive layer, the method comprising: One input end of the system moves and feeds the portion of the continuous flexible workpiece that has not been wound before, and passes through a conditioning unit, an activation surface cleaning unit, a first plating unit, a first cleaning unit, and a first a second plating unit, a second cleaning unit, a third plating unit and a cleaning-drying unit; conditioning the surface of the conductive layer in the conditioning unit to form an activating surface portion, wherein the activating surface portion is substantially Forming an active surface of the continuous flexible workpiece in electroplating; cleaning the activated surface portion of the activated surface cleaning unit; forming a precursor on the activated surface portion after the activated surface portion is to be cleaned The stack of materials includes: in the first plating unit, a gold belonging to one of the materials of the Group IB and one of the materials of the first group Electroplating on the activated surface portion to form a first material layer; cleaning the first material layer in the first cleaning unit; in the second plating unit, by belonging to the Dioxon material and the Dioxon Another metal of the material is electroplated onto the first material layer to form a second material layer, wherein the second material layer is different from the first material layer; the second material layer is cleaned in the second cleaning unit; Forming a third material layer in the third plating unit by depositing another metal belonging to the first lanthanum material and the third lanthanum material on the second material layer, 33 200832732, wherein the third material layer Unlike the first and second layers of material, the precursor stack is cleaned and dried in the cleaning-drying unit; the processed portion of the continuous flexible workpiece is picked up and wound at one of the outputs of the system. 15. For the application of the method of item 14 of the patent scope, it further includes: Cleaning the precursor stack in a third cleaning unit prior to cleaning and drying; and forming a fourth material layer on the precursor stack from a fourth deposition unit by depositing at least one Group VIA material, wherein The unit that moves the continuous flexible workpiece to and sequentially passes includes the third cleaning unit and the fourth deposition unit. 1 6. The method of claim 15, further comprising reacting the precursor stack with the fourth layer in an annealing unit, and wherein the unit that moves the continuous flexible workpiece to and sequentially passes The annealing unit is included. 17. The method of claim 16, wherein the at least one Group VI material comprises one of: Se, S, and Te. The method of claim 15, wherein the at least one Group VI material comprises one of: Se, S and Te. 34. The method of claim 15 wherein the method of claiming the precursor material is by immersing the precursor in a stack of ~: at least - 穑, 蝼 、, - va The ink solution contains the small amount of the VIA group of the genus, the nanoparticle of the group, by electroplating the at least one material of the group VIA to the deposition. , discriminate the drive stack and 20 · as in the method of claim 14 of the patent scope, after drying, in an annealing unit #^·································· At least one Group VIA material reacts; and wherein the unit through which the hydrazine is passed sequentially comprises the annealing unit. $ 'Working the workpiece to one of the following: one of the following: the electric treatment in a treatment solution, the continuation of the continuation of the workpiece, and the deposition of a θ 稹禋 日 layer on the front surface of the continuous flexible workpiece Wash the continuous The front surface of the workpiece is governed by one of the first. The barrier portion is thereby applied to form the activated electrode, wherein the electrical pattern is polarized with the cationic type. 22. The method of claim 14 deposits a seed layer on the contact layer. Wherein the conditioning comprises: 23, as in the method of claim 14th, wherein the material of the group of materials 35 200832732 comprises Cu, and wherein the material of the third group includes Ga and In, the sixth 24. The method of claim 14, further comprising: forming a fifth layer after forming the second layer, and forming a layer after forming the third layer, wherein the fifth layer is the same as the first layer, And the sixth layer is the same as the layer. 36