JP2012033730A - Method of manufacturing photoelectric conversion device - Google Patents

Abstract

A method for manufacturing a photoelectric conversion device capable of obtaining a compound semiconductor layer having a desired composition ratio using a single source precursor is provided.
A method of manufacturing a photoelectric conversion device includes a step of forming a surface layer containing a compound of a first metal element and a chalcogen element on the surface of an electrode layer 2 containing a first metal element, Applying a raw material solution containing a single source precursor having an organic ligand, a group I-B element and a group III-B element to form a precursor layer, and heating the precursor layer. And forming a chalcopyrite structure compound semiconductor layer containing a group IB element and a group III-B element.
[Selection] Figure 1

Description

  The present invention relates to a method for manufacturing a photoelectric conversion device using a compound semiconductor.

  Some solar cells use a photoelectric conversion device including a light absorption layer made of a chalcopyrite-based I-III-VI group compound semiconductor such as CIGS. In the photoelectric conversion device, for example, a first electrode layer made of, for example, Mo is formed on a substrate made of soda lime glass, and the I-III-VI group compound is formed on the first electrode layer. A light absorption layer made of a semiconductor is formed. Further, a transparent second electrode layer made of ZnO or the like is formed on the light absorption layer via a buffer layer made of ZnS, CdS or the like.

  As a manufacturing method for forming a semiconductor layer constituting such a light absorption layer, a manufacturing method for reducing cost is used instead of a high-cost manufacturing method using a vacuum system such as a sputtering method which has been conventionally used. Development is underway.

In Patent Document 1, a single source precursor (single source precursor) in which Cu, Se, In, or Ga is present in one organic compound is dissolved in an organic solvent, applied, and heat-treated. Thus, it is described that a Cu (In, Ga) Se ₂ semiconductor layer is formed.

The production method of the single source precursor of Patent Document 1 will be specifically described. A metal complex such as Cu (CH ₃ CN) ₄ .PF ₆ is reacted with a Lewis base such as P (C ₆ H ₅ ) _3. By producing a complex of the form {P (C ₆ H ₅ ) ₃ } ₂ Cu (CH ₃ CN) ₂ ⁺ and reacting this complex with a complex containing In or Ga and Se, Single source precursors containing Cu, In or Ga, Se are fabricated.

US Pat. No. 6,992,202

  When the single source precursor solution of Patent Document 1 is applied on the first electrode layer and heat-treated, the composition ratio of the IB group element and the III-B group element is the composition ratio in the single source precursor. Unlike the above, an I-III-VI group compound semiconductor having a desired composition ratio cannot be obtained. In particular, group III-B elements tend to decrease after heat treatment.

  The objective of this invention aims at providing the manufacturing method of the photoelectric conversion apparatus which can obtain the compound semiconductor layer of a desired composition ratio using a single source precursor.

  The method for manufacturing a photoelectric conversion device according to an embodiment of the present invention includes a step of forming a surface layer containing a compound of the first metal element and a chalcogen element on the surface of the electrode layer containing the first metal element. Applying a raw material solution containing a single source precursor having an organic ligand, a group I-B element and a group III-B element on the surface layer to form a precursor layer; Heating the precursor layer to form a compound semiconductor layer having a chalcopyrite structure containing the IB group element and the III-B group element.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to form favorably the photoelectric conversion apparatus which has a compound semiconductor layer of a desired composition ratio using a single source precursor.

It is a perspective view which shows an example of embodiment of a photoelectric conversion apparatus. It is sectional drawing of the photoelectric conversion apparatus of FIG.

  FIG. 1 is a perspective view illustrating an example of an embodiment of a photoelectric conversion device manufactured using the method for manufacturing a photoelectric conversion device of the present invention, and FIG. 2 is a cross-sectional view thereof. The photoelectric conversion device 10 includes a substrate 1, a first electrode layer 2, a first semiconductor layer 3, a second semiconductor layer 4, and a second electrode layer 5. In the present embodiment, an example in which the first semiconductor layer 3 is a light absorption layer and the second semiconductor layer 4 is a buffer layer bonded to the first semiconductor layer 3 is not limited to this. The second semiconductor layer 4 may be a light absorption layer. Moreover, although the photoelectric conversion apparatus 10 in this embodiment has shown what light injects from the 2nd electrode layer 5 side, it is not limited to this, Light is incident from the board | substrate 1 side, Also good.

  1 and 2, a plurality of photoelectric conversion devices 10 are formed side by side. The photoelectric conversion device 10 includes a third electrode layer 6 provided on the substrate 1 side of the first semiconductor layer 3 so as to be separated from the first electrode layer 2. The second electrode layer 5 and the third electrode layer 6 are electrically connected by the connection conductor 7 provided in the first semiconductor layer 3. The third electrode layer 6 is integrated with the first electrode layer 2 of the adjacent photoelectric conversion device 10. With this configuration, adjacent photoelectric conversion devices 10 are connected in series. In one photoelectric conversion device 10, the connection conductor 7 is provided so as to penetrate the first semiconductor layer 3 and the second semiconductor layer 4, and the first electrode layer 2 and the second electrode layer are provided. The first semiconductor layer 3 and the second semiconductor layer 4 sandwiched between 5 and 5 perform photoelectric conversion.

  The substrate 1 is for supporting the photoelectric conversion device 10. Examples of the material used for the substrate 1 include glass, ceramics, resin, and metal.

  The first electrode layer 2 and the third electrode layer 6 are made of a conductor such as Mo, Al, Ti, or Au, and are formed on the substrate 1 by a sputtering method or a vapor deposition method.

The first semiconductor layer 3 is mainly composed of an I-III-VI group compound semiconductor. The group I-III-VI compound semiconductor is a group I-B element (in this specification, the name of the group follows the short-period periodic table. Note that the group I-B element is a long-period period of IUPAC. In the table, it is a compound semiconductor of a group 11 element), a group III-B element (also referred to as a group 13 element), and a group VI-B element (also referred to as a group 16 element), has a chalcopyrite structure, and has chalcopyrite. This is called a compound compound semiconductor (also called a CIS compound semiconductor). Examples of the I-III-VI group compound semiconductor include Cu (In, Ga) Se ₂ (also referred to as CIGS), Cu (In, Ga) (Se, S) ₂ (also referred to as CIGSS), and CuInS ₂ (CIS). Also called). Cu (In, Ga) Se ₂ refers to a compound mainly composed of Cu, In, Ga, and Se. Cu (In, Ga) (Se, S) ₂ refers to a compound mainly composed of Cu, In, Ga, Se, and S. Such an I-III-VI group compound semiconductor has a high photoelectric conversion efficiency, and an effective electromotive force can be obtained even when used as a thin layer of 10 μm or less.

Such a first semiconductor layer 3 is manufactured as follows. First, a solution for a semiconductor layer for forming the first semiconductor layer 3 is prepared. The semiconductor layer solution includes a step of producing a first complex solution, a step of producing a second complex solution, a step of producing a precipitate having a single source precursor, and a step of producing a solution for a semiconductor layer. And is produced. Each manufacturing process will be described in detail below.

(Process for preparing the first complex solution)
A first complex solution in which a first complex containing a Lewis base (hereinafter, the Lewis base used for the first complex is referred to as a first Lewis base) and a group IB element is prepared. As the first Lewis base, a VB group element (also referred to as a Group 15 element) such as P (C ₆ H ₅ ) ₃ , As (C ₆ H ₅ ) ₃ and N (C ₆ H ₅ ) ₃ is included. An organic compound is mentioned. As the raw material of the I-B group _element, Cu (CH 3 _CN) organometallic complex such as 4 · PF ₆ and the like. The organic ligand used in this organometallic complex is preferably less basic than the first Lewis base. In addition, by dissolving a metal salt of a group IB element such as CuCl, CuCl ₂ , CuBr, and CuI in an organic solvent functioning as a ligand such as acetonitrile, the group I-B element coordinated with acetonitrile is obtained. An organometallic complex may be used. Examples of the organic solvent for the first complex solution include acetonitrile, acetone, methanol, ethanol, and isopropanol.

The first Lewis base is L, and an organometallic complex of an IB group element is [M′R ′ ₄ ] ⁺ (X ′) ⁻ (M ′ is an IB group element, and R ′ is an arbitrary organic coordination. And (X ′) ⁻ represents an arbitrary anion), and when the first complex is [L ₂ M′R ′ ₂ ] ⁺ (X ′) ⁻ , the reaction for forming the first complex is Is expressed as Reaction Scheme 1.

As a specific example of Reaction Formula 1, for example, the first Lewis base L is P (C ₆ H ₅ ) ₃ , and the organometallic complex [M′R ′ _m ] ⁺ (X ′) ⁻ is a Cu group element. In the case of (CH ₃ CN) ₄ · PF ₆ , the first complex [L _n M′R ′ _(mn) ] ⁺ (X ′) ⁻ is {P (C ₆ H ₅ ) ₃ } ₂ Cu (CH ₃ CN) ₂ · PF ₆

(Preparation process of second complex solution)
Chalcogen element-containing organic compound (hereinafter, the chalcogen element-containing organic compound used for the second complex is referred to as the first chalcogen element-containing organic compound) and III-B group element (hereinafter, the III-B group element used for the second complex solution) A second complex solution containing a second complex containing the first III-B group element) is prepared. The chalcogen element-containing organic compound is an organic compound having a chalcogen element (the chalcogen element means S, Se, or Te among VI-B group elements), for example, acrylic, allyl, alkyl, vinyl, perfluoro Thiol, selenol, tellurol, and the like in which a chalcogen element is bonded to an organic compound such as carbamate. In addition, examples of the material of the first group III-B element include metal salts such as InCl ₃ and GaCl ₃ . Moreover, methanol, ethanol, propanol etc. are mentioned as an organic solvent of a 2nd complex solution.

The chalcogen element is E, the metal salt of the first chalcogen element-containing organic compound is A (ER ″) (R ″ is an organic compound, A is an arbitrary cation), and the first III-B group The metal salt of the element is M ″ (X ″) ₃ (M ″ is a first group III-B element, and X ″ is an arbitrary anion), and the second complex is A ⁺ [M ′ When “(ER ″) ₄ ] ^— , the reaction for forming the second complex is represented by Reaction Formula 2. The metal salt A (ER ″) of the first chalcogen element-containing organic compound is composed of a metal alkoxide such as NaOCH ₃ and a first chalcogen element-containing organic compound such as phenyl selenol (HSeC ₆ H ₅ ). Is obtained by reacting.

As a specific example of Reaction Formula 2, for example, the metal salt A (ER ″) of the first chalcogen element-containing organic compound is NaSeC ₆ H ₅ , and the metal salt M ″ (X ′ ') ₃ is InCl ₃ or GaCl ₃ ,
In this case, the second complex A ⁺ [M ″ (ER ″) ₄ ] ⁻ is converted to Na ⁺ [In (SeC ₆ H ₅ ) ₄ ] ⁻ or Na ⁺ [Ga (SeC ₆ H ₅ ) ₄ ] ^−. Generate.

  In addition, the 1st group III-B element contained in a 2nd complex solution is not restricted to one type, Multiple types may be contained. For example, both In and Ga may be included in the second complex solution. Such a second complex solution can be prepared by using a mixture of a plurality of types of metal salts of the first group III-B elements as a raw material of the second complex solution. Or you may produce the 2nd complex solution containing 1 type of 1st III-B group elements for every 1st III-B group element, and mix these.

(Preparation process of a precipitate having a single source precursor)
By mixing the first complex solution and the second complex solution prepared as described above, the first complex reacts with the second complex, and the IB group element such as Cu, the first complex such as In and Ga, etc. A precipitate is formed comprising a single source precursor containing one III-B element and a chalcogen element such as Se. The reaction to form such a single source precursor [L _n M ′ (ER ″) ₂ M ″ (ER ″) ₂ ] is represented by Reaction Scheme 3.

Specific examples of Scheme 3, the first complex is _{{P (C 6 H 5)} 3} 2 Cu (CH 3 CN) 2 · PF 6, second complex is _{^{Na + [M '' (SeC}} 6 H 5) ₄ ] ^- (M ″ is In and / or Ga), the single source precursor is {P (C ₆ H ₅ ) ₃ } ₂ Cu (SeC ₆ H ₅ ) ₂ M ″ (SeC ₆ H ₅ ) ₂

And it isolate | separates into the deposit containing this single source precursor, and the solution of the upper part of a deposit, discharges | emits a solution part, and takes out the precipitate containing a single source precursor.

  The temperature when the first complex and the second complex are reacted is preferably 0 to 30 ° C., and the reaction time is preferably 1 to 5 hours. In order to remove impurities such as Na and Cl, the portion precipitated by the reaction is desirably washed using a technique such as centrifugation or filtration.

(Process for preparing semiconductor layer solution)
The precipitate containing the above single source precursor can be prepared by dissolving in an organic solvent such as toluene, pyridine, xylene, acetone or the like.

  The semiconductor layer solution thus prepared is applied onto the first electrode layer 2 to form a precursor layer for forming a compound semiconductor. Before that, the surface of the first electrode layer 2 is formed. A surface layer containing a compound of the first metal element and the chalcogen element contained in the first electrode layer 2 is formed in advance. By forming such a surface layer, it is possible to suppress a decrease in the group I-B element and the group III-B element during the heat treatment of the precursor layer including the single source precursor, and a desired composition. A compound semiconductor having a ratio can be manufactured. That is, when a precursor layer including a single source precursor is formed on the first electrode layer 2 and heat-treated as in the prior art, a part of the single source precursor is first bonded by a chemical bond such as a coordination bond. It is considered that the structure of the single source precursor is broken by this, and it tends to be decomposed into a complex containing a group IB element and a complex containing a group III-B element. . Therefore, it is considered that when a precursor layer having such a broken single source precursor is heat-treated, part of the decomposed complex is vaporized and reduced, and the desired composition ratio is not achieved. On the other hand, it has been found that the formation of the surface layer on the surface of the first electrode layer 2 as in the present invention can suppress it.

The surface layer is preferably formed with a first thickness of 5 nm to 200 nm from the viewpoint of satisfactorily producing the first semiconductor layer 3 having good electrical connection with the first electrode layer 2. . The surface layer contains a compound of the first metal element and the chalcogen element contained in the first electrode layer 2. Thereby, adhesiveness with the 1st electrode layer 2 can be improved. The chalcogen element contained in this surface layer is preferably the same as the chalcogen element contained in the first semiconductor layer 3. As a result, the adhesion between the first electrode layer 2 and the first semiconductor layer 3 can be further enhanced, and electrical connection can be enhanced. For example, when the first electrode layer 2 is Mo and the first semiconductor layer 3 is Cu (In _x Ga _1-X ) Se ₂ (where X is 0 ≦ X ≦ 1), the surface layer is a compound of Mo and Se such as MoSe _2.

  Such a surface layer is formed by, for example, heating the surface of the first electrode layer 2 with the first metal layer 2 by heating the first electrode layer 2 containing the first metal element in an atmosphere containing the chalcogen element. It can be formed by chemically changing to a compound of an element and a chalcogen element. By using such a method, the surface layer can be easily formed and the adhesion between the first electrode layer 2 and the surface layer can be improved. As another method for forming the surface layer, a method of forming a compound of a first metal element and a chalcogen element on the first electrode layer 2 using a thin film forming method such as a sputtering method, And a method of chemically reacting the first metal element and the chalcogen element contained in the first electrode layer 2 by applying an organic compound containing the chalcogen element on the electrode layer 2 and then heat-treating the organic compound. .

  On the first electrode layer 2 thus formed with the surface layer, the semiconductor layer solution is applied using a spin coater, screen printing, dipping, spraying, or a die coater, and dried to form a precursor layer. To do. Drying is desirably performed in a reducing atmosphere. The temperature at the time of drying is 50-300 degreeC, for example. During this drying, the organic components may be pyrolyzed.

  And the said precursor layer is heat-processed and the 1st semiconductor layer 3 with a thickness of 1.0-2.5 micrometers is produced. The heat treatment is preferably performed in a reducing atmosphere in order to prevent oxidation and form a good semiconductor layer. The reducing atmosphere in the heat treatment is preferably a nitrogen atmosphere, a forming gas atmosphere, a hydrogen atmosphere, or the like. The heat treatment temperature is, for example, 400 ° C to 600 ° C.

The precursor layer can react with a chalcogen element contained in a chalcogen element-containing organic compound in a single source precursor as a raw material to form a group I-III-VI compound semiconductor. It may be dissolved separately in the preparation solution. Alternatively, the precursor layer may be heat-treated while supplying a gas containing a chalcogen element. As a result, the chalcogen element that is easily deficient due to evaporation or the like can be sufficiently supplied to obtain the desired first semiconductor layer 3. Examples of the gas containing the chalcogen element include S vapor, Se vapor, H ₂ S, and H ₂ Se.

  By stacking a second semiconductor layer 4 having a conductivity type different from that of the first semiconductor layer 3 on the first semiconductor layer 3, the photoelectric conversion device 10 can be obtained. The second semiconductor layer 4 has a conductivity type different from that of the first semiconductor layer 3, and the electric power generated by light irradiation between the first semiconductor layer 3 and the second semiconductor layer 4 is well separated to provide power. Can be obtained. For example, when the first semiconductor layer 3 is a p-type semiconductor, the second semiconductor layer 4 is an n-type semiconductor. Note that another layer may be interposed at the interface between the first semiconductor layer 3 and the second semiconductor layer 4. Examples of such other layers include an i-type semiconductor layer and a buffer layer that forms a heterojunction with the first semiconductor layer 3. In the present embodiment, the second semiconductor layer 4 functions as a buffer layer that performs a heterojunction with the first semiconductor layer 3 and functions as a semiconductor layer having a conductivity type different from that of the first semiconductor layer 3. Also serves as.

Examples of the second semiconductor layer 4 include CdS, ZnS, ZnO, In ₂ Se ₃ , In (OH, S), (Zn, In) (Se, OH), and (Zn, Mg) O. It is formed with a thickness of 10 to 200 nm by a chemical bath deposition (CBD) method or the like. In (OH, S) refers to a compound mainly composed of In, OH, and S. (Zn, In) (Se, OH) refers to a compound mainly composed of Zn, In, Se, and OH. (Zn, Mg) O refers to a compound mainly composed of Zn, Mg and O.

  The second electrode layer 5 is a 0.05 to 3.0 μm transparent conductive film such as ITO or ZnO. The second electrode layer 5 is preferably made of a semiconductor having a conductivity type different from that of the first semiconductor layer 3 in order to improve translucency and conductivity. The second electrode layer 5 is formed by sputtering, vapor deposition, chemical vapor deposition (CVD), or the like. The second electrode layer 5 is a layer having a resistivity lower than that of the second semiconductor layer 4, and is for taking out charges generated in the first semiconductor layer 3. From the viewpoint of taking out charges well, it is preferable that the resistivity of the second electrode layer 5 is less than 1 Ω · cm and the sheet resistance is 50 Ω / □ or less.

  In order to increase the absorption efficiency of the first semiconductor layer 3, it is preferable that the second electrode layer 5 has optical transparency with respect to the absorbed light of the first semiconductor layer 3. The second electrode layer 5 has a thickness of 0.05 to 0.5 μm from the viewpoint of enhancing the light transmittance and at the same time enhancing the light reflection loss prevention effect and the light scattering effect and further transmitting the current generated by the photoelectric conversion. Thickness is preferred. From the viewpoint of preventing light reflection loss at the interface between the second electrode layer 5 and the second semiconductor layer 4, the refractive indexes of the second electrode layer 5 and the second semiconductor layer 4 are equal. preferable.

A plurality of photoelectric conversion devices 10 can be arranged and electrically connected to form a photoelectric conversion module. In order to easily connect adjacent photoelectric conversion devices 10 in series, as shown in FIGS. 1 and 2, the photoelectric conversion device 10 has a first electrode layer 2 on the substrate 1 side of the first semiconductor layer 3.
And a third electrode layer 6 provided apart from each other. The second electrode layer 5 and the third electrode layer 6 are electrically connected by the connection conductor 7 provided in the first semiconductor layer 3.

  The connection conductor 7 is made of a material having a lower electrical resistivity than the first semiconductor layer 3. Such a connection conductor 7 can be formed, for example, by forming a groove penetrating the first semiconductor layer 3 and the second semiconductor layer 4 and forming a conductor in the groove. As such a conductor, for example, after forming a groove penetrating the first semiconductor layer 3 and the second semiconductor layer 4, the second electrode layer 5 is also formed in the groove, thereby connecting conductor 7. Can be formed (see FIGS. 1 and 2). Further, the connection conductor 7 may be formed by filling the groove with a conductive paste.

  As shown in FIGS. 1 and 2, a collecting electrode 8 may be formed on the second electrode layer 5. The collecting electrode 8 is for reducing the electric resistance of the second electrode layer 5. From the viewpoint of increasing light transmittance, the thickness of the second electrode layer 5 is preferably as thin as possible, but if it is thin, the conductivity is lowered. However, since the current collecting electrode 8 is provided on the second electrode layer 5, the current generated in the first semiconductor layer 3 can be taken out efficiently. As a result, the power generation efficiency of the photoelectric conversion device 10 can be increased.

  For example, as shown in FIG. 1, the collector electrode 8 is formed in a linear shape from one end of the photoelectric conversion device 10 to the connection conductor 7. Thereby, the current generated by the photoelectric conversion of the first semiconductor layer 3 is collected to the current collecting electrode 8 via the second electrode layer 5, and this current is collected to the adjacent photoelectric conversion device 10 via the connection conductor 7. It can conduct well. Therefore, by providing the current collecting electrode 8, the current generated in the first semiconductor layer 3 can be efficiently taken out even if the second electrode layer 5 is thinned. As a result, power generation efficiency can be increased.

  The collector electrode 8 preferably has a width of 50 to 400 μm from the viewpoint of suppressing light from being blocked to the first semiconductor layer 3 and having good conductivity. The current collecting electrode 8 may have a plurality of branched portions.

  The collector electrode 8 can be formed, for example, by printing a metal paste in which a metal powder such as Ag is dispersed in a resin binder or the like in a pattern and curing it.

  The collector electrode 8 is preferably provided so as to reach the outer peripheral end of the light absorption layer 3 in plan view. With such a configuration, the current collecting electrode 8 protects the outer peripheral portion of the light absorbing layer 3, suppresses chipping in the outer peripheral portion of the light absorbing layer 3, and improves photoelectric conversion also in the outer peripheral portion of the light absorbing layer 3. It can be carried out. Further, the current generated at the outer peripheral portion of the light absorption layer 3 can be efficiently taken out by the collecting electrode 8 reaching the outer peripheral end portion. As a result, power generation efficiency can be increased.

About the manufacturing method of the photoelectric conversion apparatus of this invention, it evaluated as follows. First, 10 mmol of Cu (CH ₃ CN) ₄ .PF ₆ as an organometallic complex of a group I-B element and 20 mmol of P (C ₆ H ₅ ) ₃ as a first Lewis base were each added to 100 ml of acetonitrile. Dissolved. After confirming that these solutions were uniformly dissolved, the solution was stirred with a magnetic stirrer at room temperature for 5 hours to prepare a first complex solution containing the first complex.

On the other hand, 40 mmol of NaOCH ₃ and 40 mmol of HSeC ₆ H ₅ were dissolved in 300 ml of methanol, and then 7 mmol of InCl ₃ and ₃ mmol of GaCl ₃ were dissolved. After confirming complete dissolution, the mixture was stirred with a magnetic stirrer at room temperature for 5 hours to prepare a second complex solution containing the second complex.

  Next, the second complex solution was dropped into the first complex solution at a rate of 10 ml per minute. Table 1 shows the charged compositions of Cu, Se, In, and Ga. Thereby, it was confirmed that a white precipitate was generated during the dropping. After completion of the dropwise addition, the mixture was stirred at room temperature for 1 hour with a magnetic stirrer. As a result, a precipitate was precipitated.

  In order to take out only this precipitate, the operation of separating the solvent with a centrifuge, dispersing it in 500 ml of methanol, and subjecting it to centrifugation was repeated twice. As a result, it was confirmed that the residual amount of Na in the final product was 1 ppm or less.

  The precipitate was dried at room temperature in a vacuum to remove the solvent, and then the composition of the precipitate was analyzed by emission spectroscopic analysis (ICP). As a result, it was confirmed that the precipitate was a single source precursor containing triphenylphosphine, phenyl selenol, Cu, In and Ga. The molar ratio of Cu, In, Ga, and Se in the precipitate was 1.04: 0.77: 0.23: 4.05.

Moreover, 10 mmol of pyridine and 4 mmol of HSeC ₆ H ₅ were mixed as a composition adjustment of the raw metal element, and 1 mmol of metal indium was dissolved in this mixed solution to prepare a third complex solution.

  And the solution for semiconductor layers whose molar ratio of Cu, In, and Ga is 0.95: 0.79: 0.21 was formed by melt | dissolving said precipitate in this 3rd complex solution.

Next, a soda lime glass substrate 1 having a first electrode layer 2 made of Mo on the surface is heated in a hydrogen atmosphere containing Se, and a surface of MoSe _{2 having} a thickness of 10 nm is formed on the first electrode layer 2. A layer was formed. And in the glove box made into nitrogen gas atmosphere, the said solution for semiconductor layers is apply | coated by the doctor blade method on the 1st electrode layer 2 in which the said surface layer was formed, and this is heated at 110 degreeC with a hotplate. Then, the precursor layer was formed by drying for 5 minutes.

  And the heat processing of this precursor layer was implemented in hydrogen gas atmosphere. The heat treatment was performed by rapidly raising the temperature to 525 ° C. in 5 minutes and holding at 525 ° C. for 1 hour, followed by natural cooling to produce the first semiconductor layer 3 made of a compound semiconductor thin film having a thickness of 1.5 μm.

  Thereafter, cadmium acetate and thiourea were dissolved in aqueous ammonia, and the sample was immersed in the solution to form a second semiconductor layer 4 made of CdS having a thickness of 0.05 μm on the first semiconductor layer 3. Further, an Al-doped zinc oxide film (second electrode layer 5) was formed on the second semiconductor layer 4 by a sputtering method. Finally, an aluminum electrode (extraction electrode) was formed by vapor deposition to produce a photoelectric conversion device 10 as a sample.

In addition, as a comparative example, a photoelectric conversion device in which a MoSe ₂ surface layer was not formed on the first electrode layer was manufactured. The photoelectric conversion device as a comparative example was manufactured in the same manner as the photoelectric conversion device as the sample, but the surface layer was not formed on the surface of the first electrode layer.

Composition analysis of each first semiconductor layer of the photoelectric conversion device as a sample manufactured as described above and the photoelectric conversion device as a comparative example was performed. As a result, the first semiconductor layer has a molar ratio of Cu, In, and Ga of 1.15: 0.96: 0.04, and the amount of Ga is reduced compared to the composition of the solution for forming a semiconductor. It was. On the other hand, in the sample produced by the production method of the present invention, the molar ratio of Cu, In, and Ga is 0.96: 0.80: 0.20, which is close to the composition of the semiconductor forming solution, It was found that a part of the metal could be suppressed from decreasing.

  It should be noted that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the present invention.

1: Substrate 2: First electrode layer 3: First semiconductor layer 4: Second semiconductor layer 5: Second electrode layer 6: Third electrode layer 7: Connection conductor 8: Current collecting electrode 10: Photoelectric Conversion device

Claims (4)

Forming a surface layer containing a compound of the first metal element and a chalcogen element on the surface of the electrode layer containing the first metal element;
Applying a raw material solution containing a single source precursor having an organic ligand, a group IB element and a group III-B element on the surface layer to form a precursor layer;
And heating the precursor layer to form a chalcopyrite structure compound semiconductor layer containing the IB group element and the III-B group element. .   The method for manufacturing a photoelectric conversion device according to claim 1, wherein Mo is included as the first metal element, and Se is included as the chalcogen element. The method for manufacturing a photoelectric conversion device according to claim 1, wherein Cu (In _x Ga _1-X ) Se ₂ (where X is 0 ≦ X ≦ 1) is included in the compound semiconductor layer.   The step of forming the surface layer is a step of chemically changing the surface of the electrode layer into a compound of the first metal element and the chalcogen element by heating the electrode layer in an atmosphere containing the chalcogen element. The manufacturing method of the photoelectric conversion apparatus in any one of Claims 1 thru | or 3.

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