Device and method for preparing CIGS solar cell absorption layer at low temperature

Abstract

The invention discloses a device and method for preparing a CIGS solar cell absorption layer at a low temperature, and belongs to the technical field of solar cells, the device mainly comprises a process cavity, evaporation sources and an artificial lightning system, and the process cavity comprises a pretreatment cavity, three evaporation cavities and a cooling cavity; the evaporation source comprises an H2Se evaporation source communicated with the three evaporation cavities, a Cu evaporation source communicated with the second evaporation cavity, and an In and Ga evaporation source communicated with the first evaporation cavity and the third evaporation cavity; and the artificial lightning system is arranged at the tops of the pretreatment cavity and the evaporation cavity and is used for carrying out instantaneous high-energy treatment on the substrate. According to the preparation method, the preparation device is utilized, three elements of Cu, In and Ga are evaporated in different cavities in three steps under the H2Se atmosphere, the substrate is subjected to instantaneous high-energy treatment through an artificial lightning system after each step of evaporation, traditional substrate heating is replaced, energy is greatly saved, meanwhile, the process is more controllable, and the production cost is reduced. And an absorption layer with a chalcopyrite structure can be formed, so that the conversion efficiency of the CIGS solar cell is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of solar cells, and specifically discloses a device and a method for preparing an absorption layer of a CIGS solar cell at low temperature. Background Art

[0002] Copper indium gallium selenide (CIGS) solar cells are thin-film solar cells with a chalcopyrite crystal structure. They have the advantages of low cost, good power generation stability, and high conversion efficiency. They are considered to be the most promising thin-film solar cells. Their cell structure is mainly composed of soda-lime glass / back electrode layer / absorption layer / buffer layer / window layer / transparent conductive layer. At present, high-performance CIGS solar cells are mainly made by a three-step co-evaporation method. When preparing the CIGS film layer, the substrate generally needs to be heated, which consumes a lot of energy and is costly. In addition, it cannot be applied to flexible substrates such as flexible PI (polyimide) substrates, which greatly limits the industrialization process of CIGS solar cells. Therefore, there is an urgent need for a method to produce high-efficiency CIGS solar cells without heating the substrate. Summary of the invention

[0003] The purpose of the present invention is to solve the problem that the prior art requires heating of the substrate, which consumes high energy and has high cost, and cannot be applied to flexible substrates such as flexible PI substrates, which greatly limits the industrialization process of CIGS solar cells. A device and method for low-temperature preparation of CIGS solar cell absorption layers are proposed. This method uses an artificial lightning system to perform instantaneous high-energy treatment on different stages of evaporation, replacing traditional substrate heating, which greatly saves energy and makes the process more controllable.

[0004] In order to solve the above technical problems, the present invention provides a device for preparing a CIGS solar cell absorption layer at low temperature, comprising:

[0005] The process chamber comprises a pretreatment chamber, an evaporation chamber and a cooling chamber which are arranged in sequence, wherein the evaporation chamber comprises a first evaporation chamber, a second evaporation chamber and a third evaporation chamber which are arranged in sequence;

[0006] A transmission system, arranged at the bottom of the process chamber, for transmitting the substrate;

[0007] A vacuum system, which is in communication with the process chamber and is used to provide vacuum for the process chamber;

[0008] The oil heating system is connected with the heating pipes in the walls of the pretreatment chamber and the evaporation chamber;

[0009] A water cooling system communicates with a cooling pipe in a wall of the cooling chamber;

[0010] Evaporation sources, including H 2Se (selenide) evaporation source, Cu (copper) evaporation source, In (indium) evaporation source and Ga (gallium) evaporation source, the evaporation source is connected to the evaporation chamber through a connecting pipe, wherein H 2 The Se evaporation source is communicated with the first evaporation chamber, the second evaporation chamber, and the third evaporation chamber, the Cu evaporation source is communicated with the second evaporation chamber, and the In evaporation source and the Ga evaporation source are communicated with the first evaporation chamber and the third evaporation chamber;

[0011] The artificial lightning system is located at the top of the pretreatment chamber and the evaporation chamber and is used to perform instantaneous high-energy treatment on the substrate.

[0012] As a further description of the present invention, a cooling fan is also provided in the cooling chamber.

[0013] As a further description of the present invention, an inlet door is provided at the entrance of the pretreatment chamber, an outlet door is provided at the outlet of the cooling chamber, and isolation doors are provided between the pretreatment chamber, the first evaporation chamber, the second evaporation chamber, the third evaporation chamber and the cooling chamber.

[0014] As a further description of the present invention, position sensors are provided on the chamber entrance door, the isolation door and the chamber exit door.

[0015] As a further description of the present invention, a heating resistance wire is provided in each of the evaporation sources.

[0016] As a further description of the present invention, a control valve is provided on the connecting pipeline.

[0017] As a further description of the present invention, a pipeline heating device is provided on the connecting pipeline.

[0018] In order to solve the above technical problems, the present invention also provides a method for preparing a CIGS solar cell absorption layer at low temperature, comprising the following steps:

[0019] (1) Using an artificial lightning system in a pretreatment chamber to perform instantaneous high-energy treatment on a substrate with a back electrode;

[0020] (2) Transfer to the first evaporation chamber, in H 2 In and Ga are co-evaporated and deposited on the back electrode in a Se atmosphere at a deposition rate of 80-100 nm / min for 4-6 min. After the deposition is completed, an artificial lightning system is used for instantaneous high-energy treatment.

[0021] (3) Transfer to the second evaporation chamber, in H 2 Cu was evaporated and deposited in a Se atmosphere at a deposition rate of 100-140 nm / min for 4-6 min. After the deposition was completed, an artificial lightning system was used for instantaneous high-energy treatment.

[0022] (4) Transfer to the third evaporation chamber, in H 2In and Ga are deposited by co-evaporation compensation in Se atmosphere, with a compensation deposition rate of 60-90 nm / min and a deposition time of 1-3 min. After the deposition is completed, an artificial lightning system is used for instantaneous high-energy treatment;

[0023] (5) The product is transferred to a cooling chamber for cooling and crystallization, thereby completing the preparation of the absorption layer of the CIGS solar cell.

[0024] As a further description of the present invention, the atomic fraction ratio of In:Ga:Se in step (2) is (10-20):(5-10):(70-85); the atomic fraction ratio of Cu:In:Ga:Se in step (3) is (28-35):(8-15):(4-7):(40-58); the atomic fraction ratio of Cu:In:Ga:Se in step (4) is (25-30):(16-22):(6-10):(35-45).

[0025] The method of the present invention utilizes a device for preparing the absorption layer of a CIGS solar cell at low temperature, adopts a step-by-step evaporation method to deposit the four elements of Cu, In, Ga and Se on a substrate, and utilizes an artificial lightning system to perform instantaneous high-energy treatment on different stages of evaporation, which can replace traditional substrate heating, greatly save energy, and also make the process more controllable, and can be applied to large-scale, commercial production; at the same time, this method can also be applied to low-temperature flexible substrates such as flexible PI, ultra-thin flexible glass and other substrates to produce flexible CIGS solar cells; this method is a physical method, the process is stable, and the process is controllable and pollution-free.

[0026] In order to solve the above technical problems, the present invention also provides a method for preparing a CIGS solar cell. The absorption layer of the CIGS solar cell is prepared by the above method.

[0027] Due to the adoption of the above technical solution, the beneficial effects of the present invention are:

[0028] (1) The device of the present invention is provided with three evaporation chambers connected in sequence, and the three evaporation chambers are connected to H 2 Se evaporation source is connected, and both are equipped with artificial lightning system to make the substrate 2 In the Se atmosphere, In, Ga and Cu are deposited in three different evaporation chambers by evaporation step by step, and In and Ga are deposited in addition. After each step of evaporation, the artificial lightning system can be used for instantaneous high-energy treatment to form an absorption layer with a chalcopyrite structure. In addition, the cavity wall of the evaporation chamber is heated by oil heating to ensure that the cavity wall does not condense the evaporated material; the cooling cavity is cooled by a water cooling system and a cold air blower, which is conducive to the crystallization of the absorption layer; each evaporation source is heated by a resistance wire to ensure that the activity of the evaporated atoms does not decrease.

[0029] (2) The method of the present invention utilizes a device for preparing the CIGS solar cell absorption layer at low temperature, performs evaporation deposition of the CIGS absorption layer according to a certain process flow, and simultaneously uses an artificial lightning system for instantaneous high-energy processing, thereby eliminating the need for substrate heating and temperature monitoring. 2 Cu, In and Ga are evaporated in three steps in different chambers under Se atmosphere. After each step of evaporation, the substrate is subjected to instantaneous high-energy treatment using an artificial lightning system to form an absorption layer with a chalcopyrite structure. In addition, Ga forms a "V"-shaped gradient band gap during the entire evaporation process, which effectively improves the collection capacity of photogenerated carriers and greatly increases the conversion efficiency of CIGS solar cells.

[0030] (3) In the CIGS co-evaporation process, an artificial lightning system is used to replace the traditional method of heating the substrate with a resistance wire, which not only greatly saves energy costs, but also avoids high-temperature treatment, making the production process more stable and controllable, and achieving the goal of low temperature and high efficiency;

[0031] (4) The method of the present invention is not only applicable to glass substrates, but can also be applied to low-temperature flexible substrates such as flexible PI and ultra-thin flexible glass to produce flexible CIGS solar cells;

[0032] (5) The continuous and rapid absorption layer preparation method can be applied to large-scale, large-size and continuous production, providing technical support for the mass production of CIGS solar cells. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 A schematic diagram of a device for preparing a CIGS solar cell absorption layer at low temperature according to the present invention;

[0034] Figure 2 Schematic diagram of the absorption layer formation of CIGS solar cells assisted by artificial lightning systems. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments.

[0036] Embodiment 1:

[0037] This embodiment provides a device for preparing the absorption layer of a CIGS solar cell at low temperature. Figure 1 As shown, including:

[0038] A process chamber, comprising a pretreatment chamber 110, an evaporation chamber and a cooling chamber 130 which are arranged in sequence, wherein the evaporation chamber comprises a first evaporation chamber 121, a second evaporation chamber 122 and a third evaporation chamber 123 which are arranged in sequence, an inlet door 141 is arranged at the entrance of the pretreatment chamber 110, an outlet door 143 is arranged at the outlet of the cooling chamber 130, an isolation door 142 is arranged between the pretreatment chamber 110, the first evaporation chamber 121, the second evaporation chamber 122, the third evaporation chamber 123 and the cooling chamber 130; and position sensors 150 are arranged on the inlet door 141, the isolation door 142 and the outlet door 143;

[0039] The transport system 200 includes a transport roller disposed at the bottom of the process chamber and used for transporting the substrate;

[0040] A vacuum system 300 is communicated with the process chamber and is used to provide vacuum for the process chamber;

[0041] The oil heating system 400 is connected to the heating pipes in the pretreatment chamber 110 and the evaporation chamber wall. The oil heating system and the heating pipes can maintain the activity of the materials and prevent the materials from sticking to the chamber wall.

[0042] The water cooling system 500 is connected to the cooling pipe in the wall of the cooling cavity 130;

[0043] Evaporation sources, including H 2 Se evaporation source 610, first Ga evaporation source 620, first In evaporation source 630, Cu evaporation source 640, second In evaporation source 650 and second Ga evaporation source 660, all evaporation sources are provided with heating resistance wire 670, the evaporation source is connected with the evaporation chamber through a connecting pipe, and the connecting pipe is provided with a pipe heating device 680 and a control valve 690, wherein H 2 The Se evaporation source 610 is connected to all three evaporation chambers, the first Ga evaporation source 620 and the first In evaporation source 630 are connected to the first evaporation chamber 121, the Cu evaporation source 640 is connected to the second evaporation chamber 122, and the second In evaporation source 650 and the second Ga evaporation source 660 are both connected to the third evaporation chamber 123;

[0044] The artificial lightning system 700 is disposed on the top of the pre-treatment chamber 110 and the evaporation chamber, and is used to perform instantaneous high-energy treatment on the substrate.

[0045] As an optimization of this embodiment, a cooling fan 131 is further provided in the cooling chamber 130 .

[0046] Embodiment 2:

[0047] This embodiment provides a method for preparing a CIGS solar cell absorption layer at low temperature, using the device of embodiment 1, comprising the following steps:

[0048] (1) Turn on the vacuum system 300 and evacuate the entire process chamber. The vacuum degree is required to reach 3.0×10 -6 mbar, start the oil heating system 400 and the water cooling system 500, start the transmission system 200 to make it start to rotate according to the predetermined process speed; turn on the heating resistor wire 670 of all evaporation sources to ensure that all evaporation sources reach the predetermined evaporation temperature, turn on H 2 The control valve 690 of the Se evaporation source 610 makes the three evaporation chambers filled with H 2 Se atmosphere; opening the chamber door 141, sending the glass substrate coated with the Mo back electrode into the pretreatment chamber 110, turning on the artificial lightning system 700 of the pretreatment chamber 110, and using 400,000 volt artificial lightning to perform instantaneous high-energy pretreatment on the glass substrate;

[0049] (2) The isolation door 142 between the pretreatment chamber 110 and the first evaporation chamber 121 is opened, the glass substrate enters the first evaporation chamber 121, and the control valves 690 of the first Ga evaporation source 620 and the first In evaporation source 630 are opened. 2 Co-evaporation deposition of Ga and In in an atmosphere of Se, with a deposition rate of 80-100 nm / min and a deposition time of 4-6 min. After the deposition is completed, rapid treatment is performed using 400,000 volt artificial lightning, and the atomic fraction ratio of In:Ga:Se is (10-20):(5-10):(70-85);

[0050] (3) The isolation door 142 between the first evaporation chamber 121 and the second evaporation chamber 122 is opened, the substrate enters the second evaporation chamber 122, the control valve 690 of the Cu evaporation source 640 is opened, and the H 2 Cu is evaporated and deposited in an atmosphere of Se, with a deposition rate of 100-140 nm / min and a deposition time of 4-6 min. After the deposition is completed, a 400,000 volt artificial lightning is used for rapid treatment, and the atomic fraction ratio of Cu: In: Ga: Se is (28-35): (8-15): (4-7): (40-58);

[0051] (4) The isolation door 142 between the second evaporation chamber 122 and the third evaporation chamber 123 is opened, the substrate enters the third evaporation chamber 123, the control valve 690 of the second In evaporation source 650 and the second Ga evaporation source 660 is opened, and In and In are deposited by compensation evaporation, the deposition rate is 60-90 nm / min, and the deposition time is 1-3 min. After the deposition is completed, 400,000 volt artificial lightning is used for rapid treatment, and finally the atomic fraction ratio of Cu: In: Ga: Se is (25-30): (16-22): (6-10): (35-45);

[0052] (5) The isolation door 142 between the third evaporation chamber 123 and the cooling chamber 130 is opened, and the substrate enters the cooling chamber 130. The cooling fan 132 is conducive to the formation of chalcopyrite crystals. Finally, the chamber door 143 is opened to complete the preparation of the CIGS absorption layer. The artificial lightning system assists the formation of the absorption layer of the CIGS solar cell. Figure 2 As shown, the whole process does not require substrate heating, which can greatly save production costs.

[0053] Embodiment three:

[0054] This embodiment provides a method for preparing a CIGS solar cell at low temperature, such as Figure 2 As shown, the following steps are included:

[0055] (1) A Mo film, a SiN layer and a Mo film are sequentially deposited on a glass substrate 10 by magnetron sputtering to form a back electrode 20;

[0056] (2) cleaning the substrate glass 10 with the molybdenum back electrode 20 to remove dirt;

[0057] (3) using the method of Example 2 to evaporate and deposit a CIGS absorption layer 30 on the molybdenum electrode, the CIGS absorption layer 30 comprising an In-Ga layer 31, a Cu-rich layer 32 and an In-Ga compensation layer 33;

[0058] (4) A CdS buffer layer of about 50 nm is prepared on the CIGS absorption layer by using a chemical bath method (CBD);

[0059] (5) Magnetron sputtering was used to prepare 80 nm intrinsic ZnO and about 800 nm low-resistance ZnO:Al window layer;

[0060] (6) A 900 nm AZO transparent conductive layer is prepared on the window layer by DC magnetron sputtering to finally form a CIGS solar cell.

[0061] Ga forms a "V"-shaped gradient band gap during the entire evaporation process, which effectively improves the collection capacity of photogenerated carriers and greatly increases the conversion efficiency of the battery.

[0062] Embodiment 4:

[0063] This embodiment provides a method for preparing a CIGS solar cell absorption layer at low temperature, using the device of embodiment 1, comprising the following steps:

[0064] (1) Turn on the vacuum system and evacuate the entire process chamber. The vacuum degree is required to reach 3.0×10 -6mbar, start the oil heating system and water cooling system, start the transmission roller 200 to make it start to rotate according to the predetermined process speed; turn on the heating resistor wire 650 of all evaporation sources to ensure that all evaporation sources reach the predetermined evaporation temperature, turn on H 2 Se evaporation source control valve 690, so that the three evaporation chambers are filled with H 2 Se atmosphere; opening the chamber door 141, sending the glass substrate coated with the Mo back electrode into the pretreatment chamber 110, turning on the artificial lightning system 700 of the pretreatment chamber 110, and using 500,000 volt artificial lightning to perform instantaneous high-energy pretreatment on the glass substrate;

[0065] (2) The isolation door 142 between the pretreatment chamber 110 and the first evaporation chamber 121 is opened, the glass substrate enters the first evaporation chamber 121, and the control valves 690 of the first Ga evaporation source 620 and the first In evaporation source 630 are opened. 2 Co-evaporation deposition of Ga and In in an atmosphere of Se, with a deposition rate of 80-100 nm / min and a duration of 4-6 min. After the deposition is completed, rapid treatment is performed using 500,000 volt artificial lightning, and the atomic fraction ratio of Ga:In:Se is (10-20):(5-10):(70-85);

[0066] (3) The isolation door 142 between the first evaporation chamber 121 and the second evaporation chamber 122 is opened, and the substrate enters the second evaporation chamber 122. 2 Cu is evaporated and deposited in an atmosphere of Se, with a deposition rate of 100-140 nm / min and a deposition time of 4-6 min. After the deposition is completed, a 400,000 volt artificial lightning is used for rapid treatment, and the atomic fraction ratio of Cu:Ga:In:Se is (28-35):(8-15):(4-7):(40-58);

[0067] (4) opening the isolation door 142 between the second evaporation chamber 122 and the third evaporation chamber 123, allowing the substrate to enter the third evaporation chamber 123, opening the control valve 690 of the second In evaporation source 650 and the second Ga evaporation source 660, and performing compensation evaporation deposition of In and Ga at a deposition rate of 60 to 90 nm / min for 1 to 3 min. After the deposition is completed, a 500,000 volt artificial lightning flash is used for rapid treatment, and finally the atomic fraction ratio of Cu:Ga:In:Se is (25 to 30):(16 to 22):(6 to 10):(35 to 45);

[0068] (5) The isolation door 142 between the third evaporation chamber 123 and the cooling chamber 130 is opened, and the substrate enters the cooling chamber 130. The cooling fan 132 is conducive to the formation of chalcopyrite crystals. Finally, the exit door 143 is opened to complete the preparation of the CIGS absorption layer.

[0069] Embodiment five:

[0070] This embodiment provides a method for preparing a CIGS solar cell at low temperature, such as Figure 2 As shown, the following steps are included:

[0071] (1) A Mo film, a SiN layer and a Mo film are sequentially deposited on a glass substrate 10 by magnetron sputtering to form a back electrode 20;

[0072] (2) cleaning the substrate glass 10 with the molybdenum back electrode 20 to remove dirt;

[0073] (3) using the method of Example 4 to evaporate and deposit a CIGS absorption layer 30 on the molybdenum electrode;

[0074] (4) On the CIGS absorption layer 30, a CdS buffer layer of about 50 nm is prepared by a chemical bath method (CBD);

[0075] (5) Magnetron sputtering was used to prepare 80 nm intrinsic ZnO and about 800 nm low-resistance ZnO:Al window layer;

[0076] (6) A 900 nm AZO transparent conductive layer is prepared on the window layer by DC magnetron sputtering to finally form a CIGS solar cell.

[0077] Ga forms a "V"-shaped gradient band gap during the entire evaporation process, which effectively improves the collection capacity of photogenerated carriers and greatly increases the conversion efficiency of the battery.

[0078] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them. A person skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some of the technical features may be replaced by equivalents. However, these modifications or replacements will not cause the essence of the corresponding technical solutions to deviate from the protection scope of the present invention.

Claims

1. A device for preparing a CIGS solar cell absorption layer at low temperature, characterized in that: include: The process chamber comprises a pretreatment chamber, an evaporation chamber and a cooling chamber which are arranged in sequence, wherein the evaporation chamber comprises a first evaporation chamber, a second evaporation chamber and a third evaporation chamber which are arranged in sequence; A transmission system, arranged at the bottom of the process chamber, for transmitting the substrate; A vacuum system, which is in communication with the process chamber and is used to provide vacuum for the process chamber; The oil heating system is connected with the heating pipes in the walls of the pretreatment chamber and the evaporation chamber; A water cooling system communicates with a cooling pipe in a wall of the cooling chamber; Evaporation sources, including H2Se evaporation source, Cu evaporation source, In evaporation source and Ga evaporation source, the evaporation sources are connected with the evaporation chamber through a connecting pipe, wherein the H2Se evaporation source is connected with the first evaporation chamber, the second evaporation chamber and the third evaporation chamber, the Cu evaporation source is connected with the second evaporation chamber, and the In evaporation source and the Ga evaporation source are connected with the first evaporation chamber and the third evaporation chamber; The artificial lightning system is located at the top of the pretreatment chamber and the evaporation chamber and is used to perform instantaneous high-energy treatment on the substrate.

2. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 1, characterized in that: A cooling fan is also arranged in the cooling chamber.

3. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 1, characterized in that: An inlet door is arranged at the entrance of the pretreatment chamber, an outlet door is arranged at the outlet of the cooling chamber, and isolation doors are arranged between the pretreatment chamber, the first evaporation chamber, the second evaporation chamber, the third evaporation chamber and the cooling chamber.

4. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 3, characterized in that: The chamber entrance door and the isolation door are both provided with position sensors.

5. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 1, characterized in that: The evaporation source is provided with a heating resistance wire.

6. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 1, characterized in that: The communicating pipeline is provided with a control valve.

7. The device for preparing the absorption layer of a CIGS solar cell at low temperature according to claim 1 or 6, characterized in that: The communicating pipe is provided with a pipe heating device.

8. A method for preparing a CIGS solar cell absorption layer at low temperature, characterized in that: Utilizing the device according to any one of claims 1 to 7, comprising the following steps: (1) Using an artificial lightning system in a pretreatment chamber to perform instantaneous high-energy treatment on a substrate with a back electrode; (2) Transfer to the first evaporation chamber, co-evaporate and deposit In and Ga on the back electrode in a H2Se atmosphere, with a deposition rate of 80-100 nm / min and a deposition time of 4-6 min. After the deposition is completed, an artificial lightning system is used for instantaneous high-energy treatment; (3) Transfer to the second evaporation chamber, evaporate and deposit Cu in H2Se atmosphere, the deposition rate is 100-140nm / min, the deposition time is 4-6min, and after the deposition is completed, an artificial lightning system is used for instantaneous high energy treatment; (4) Transfer to the third evaporation chamber, co-evaporate and deposit In and Ga in a H2Se atmosphere, the compensation deposition rate is 60-90 nm / min, the deposition time is 1-3 min, and after the deposition is completed, an artificial lightning system is used for instantaneous high energy treatment; (5) The product is transferred to a cooling chamber for cooling and crystallization, thereby completing the preparation of the absorption layer of the CIGS solar cell.

9. The method for preparing a CIGS solar cell absorption layer at low temperature according to claim 8, characterized in that: The atomic fraction ratio of In:Ga:Se in step (2) is (10-20):(5-10):(70-85); the atomic fraction ratio of Cu:In:Ga:Se in step (3) is (28-35):(8-15):(4-7):(40-58); the atomic fraction ratio of Cu:In:Ga:Se in step (4) is (25-30):(16-22):(6-10):(35-45).

10. A method for preparing a CIGS solar cell, characterized in that: The absorption layer of the CIGS solar cell is prepared by the method described in claim 8 or 9.

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