JP2010232285A - Method of manufacturing photoelectric conversion device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method of manufacturing a photoelectric conversion device, by which a manufacturing cost can be reduced. <P>SOLUTION: The method of manufacturing the photoelectric conversion device having a transparent electrode layer 20, a back electrode layer 40, and an amorphous silicon layer 30 interposed between the transparent electrode layer 20 and back electrode layer 40, includes a first step of applying a liquid containing a solvent to at least one of the transparent electrode layer 20, amorphous silicon layer 30, and back electrode layer 40; a second step of generating a precursor by removing the solvent from the applied liquid; a third step of dividing the precursor by a mechanical method; and a fourth step of heat-treating the divided precursor. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  Some embodiments according to the present invention relate to a method for manufacturing a photoelectric conversion device for manufacturing a photoelectric conversion device such as a thin film solar cell.

  Conventionally, as a photoelectric conversion device, a first electrode layer formed on a substrate, a semiconductor layer formed on the first electrode and made of amorphous silicon or the like, and a second electrode layer formed on the semiconductor layer There is something with. In addition, the first electrode layer, the semiconductor layer, and the second electrode layer are irradiated with laser to form unevenness of a predetermined pattern, whereby the first electrode and the second electrode are adjacent to each other between adjacent photoelectric conversion elements. Is known which has an integrated structure by forming a current path for electrically connecting the plurality of photoelectric conversion elements in series (see, for example, Patent Document 1).

JP 7-790002 A

  However, in the conventional method, a laser is irradiated to form unevenness of a predetermined pattern, and in order to form a silicon thin film used as a semiconductor layer, a plasma CVD method (chemical vapor deposition method) is usually used. ) And other vacuum processes. For this reason, there is a problem that a large-scale and expensive device such as a laser device or a vacuum device is required, and inconveniences such as a lot of raw material gas are wasted, and the manufacturing cost of the photoelectric conversion device is increased. there were.

  Some aspects of the present invention have been made in view of the above-described problems, and an object thereof is to provide a method for manufacturing a photoelectric conversion device that can reduce manufacturing costs.

  The manufacturing method of the photoelectric conversion device according to the present invention includes a first electrode layer, a second electrode layer, and a semiconductor layer interposed between the first electrode layer and the second electrode layer. A method for manufacturing a photoelectric conversion device, wherein at least one of the first electrode layer, the semiconductor layer, and the second electrode layer is applied with a first step of applying a liquid containing a solvent. Formed by a second step of generating a precursor obtained by removing the solvent from the liquid, a third step of dividing the precursor by a mechanical method, and a fourth step of performing a heat treatment on the divided precursor. .

  According to this configuration, at least one of the first electrode layer, the semiconductor layer, and the second electrode layer is formed by the first step, the second step, the third step, and the fourth step. Here, as compared with the layer formed in the fourth step, the precursor of the layer generated in the second step has a low hardness and is easily processed. Further, in the third step, for example, since the division is performed by a mechanical method such as scratching or scribing, the laser device used in the conventional manufacturing method becomes unnecessary. Furthermore, in the fourth step, a layer constituting the photoelectric conversion device is formed by performing a heat treatment, so that the vacuum device used in the conventional manufacturing method becomes unnecessary. This can reduce wrinkles generated when dividing, reduce the number of times a large-scale and expensive device is used, and reduce the manufacturing cost of the photoelectric conversion device.

  Preferably, an amorphous silicon layer having a p-type amorphous silicon layer, an i-type amorphous silicon layer, and an n-type amorphous silicon layer is formed as the semiconductor layer, and the liquid contains silicon atoms, and the p-type amorphous silicon layer, At least one of the i-type amorphous silicon layer and the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step.

  According to this configuration, at least one of the p-type amorphous silicon layer, the i-type amorphous silicon layer, and the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. . In this case, by using a liquid containing silicon atoms as the liquid, one or more of the layers constituting the amorphous silicon layer can be formed.

  Preferably, the liquid includes a silane polymer and a dopant, and the p-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step.

  According to this configuration, the p-type amorphous silicon layer is formed by the first process, the second process, the third process, and the fourth process. In this case, a p-type amorphous silicon layer can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) and a dopant (for example, a boron compound) as the liquid.

  Preferably, the liquid includes a silane polymer, and the i-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step.

  According to this configuration, the i-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. In this case, an i-type amorphous silicon layer can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) as the liquid.

  Preferably, the liquid includes a silane polymer and a dopant, and the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step.

  According to this configuration, the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. In this case, an n-type amorphous silicon layer can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) and a dopant (for example, a phosphorus compound) as the liquid.

Preferably, the silane polymer is a hydroxylated polysilane.
According to this configuration, since a liquid containing polysilane hydroxide is used as the liquid, a high-quality silicon layer can be obtained.

  Preferably, the method includes a step of forming a zinc oxide layer on the n-type amorphous silicon layer.

  According to this configuration, since the zinc oxide layer is formed on the n-type amorphous silicon layer, the zinc oxide layer is a reflection that enhances reflection of light transmitted through the substrate, the first electrode layer, and the amorphous silicon layer. While acting as an enhancement layer, for example, it acts as a diffusion preventing layer for preventing metal fine particles contained in the second electrode layer formed on the zinc oxide layer from diffusing into the n-type amorphous silicon layer.

  Preferably, the second electrode layer is formed by the first step, the second step, the third step, and the fourth step, and the third step is a precursor of the second electrode layer. Only split.

  According to this configuration, the second electrode layer is formed by the first step, the second step, the third step, and the fourth step, and only the precursor of the second electrode layer is divided in the third step. Here, in the conventional manufacturing method, after forming the second electrode layer, the second electrode layer is divided by irradiating a laser. In this case, since not only the second electrode layer but also the amorphous silicon layer absorbs the laser, the amorphous silicon layer is also divided. On the other hand, in the manufacturing method of the present invention, since only the precursor of the second electrode layer is divided, the area of the amorphous silicon layer can be increased as compared with the conventional manufacturing method. Thereby, the photoelectric conversion efficiency of a photoelectric conversion apparatus can be improved.

Preferably, the substrate and the first electrode layer are light transmissive.
According to such a configuration, since the substrate and the first electrode layer have optical transparency, light incident on the substrate and the first electrode layer reaches the amorphous silicon layer. Accordingly, the amount of light incident on the semiconductor layer (amorphous silicon layer) can be increased, and the photoelectric conversion efficiency of the photoelectric conversion device can be improved.

It is a sectional side view explaining the structure of the photoelectric conversion apparatus manufactured with the manufacturing method of this invention. It is a figure explaining the process of forming the transparent electrode layer shown in FIG. It is a figure explaining the process of forming the amorphous silicon layer shown in FIG. It is a figure explaining the process of forming the amorphous silicon layer shown in FIG. It is a figure explaining the process of forming the zinc oxide layer shown in FIG. It is a figure explaining the process of forming the back surface electrode layer shown in FIG. It is a figure explaining the structure of the photoelectric conversion apparatus manufactured with the conventional manufacturing method.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
First, the configuration of the photoelectric conversion device in this embodiment will be described with reference to FIG. FIG. 1 is a side sectional view for explaining the structure of a photoelectric conversion device manufactured by the manufacturing method of the present invention.

  As shown in FIG. 1, the photoelectric conversion device 1 includes a substrate 10, a transparent electrode layer (first electrode layer) 20, a p-type amorphous silicon layer 31, an i-type amorphous silicon layer 32, and an n-type amorphous silicon layer. 33, an amorphous silicon layer (semiconductor layer) 30, a zinc oxide layer 34, and a back electrode layer (second electrode layer) 40 are provided.

  Here, the p-type has a p-type impurity such as boron, the n-type has an n-type impurity such as phosphorus, and the i-type (intrinsic) means that no impurity is implanted. It means a layer having a lower impurity concentration than the n-type layer.

  The substrate 10 is a substrate made of, for example, glass, and the transparent electrode layer 20 is formed on one surface of the substrate 10 and made of a conductor such as tin-added indium oxide (ITO). Moreover, the transparent electrode layer 20 is divided | segmented by the scratch process mentioned later. The amorphous silicon layer 30 is formed on the transparent electrode layer 20 and divided by a scratch process described later. The zinc oxide layer 34 is formed on the amorphous silicon layer 30. The back electrode layer 40 is formed on the zinc oxide layer 34 and divided by a scratch process described later. Thus, by dividing the transparent electrode layer 20, the amorphous silicon layer 30, and the back electrode layer 40, a current path as shown by a dotted arrow in FIG. 1 is formed, and the photoelectric conversion device 1 has a series integrated structure. is doing.

  In addition, it is preferable that the board | substrate 10 and the transparent electrode layer 20 have a light transmittance. As the substrate 10 having optical transparency, a glass substrate can be exemplified. As the transparent electrode layer 20 having optical transparency, in addition to ITO, antimony-added tin oxide (ATO), fluorine-added tin oxide (FTO), Examples thereof include aluminum-added zinc oxide (AZO) and gallium-added zinc oxide (GZO). Thereby, in FIG. 1, light incident on the substrate 10 and the transparent electrode layer 20 from below reaches the amorphous silicon layer 30.

  Next, a method for manufacturing the photoelectric conversion device 1 will be described with reference to FIGS. FIG. 2 is a diagram illustrating a process of forming the transparent electrode layer shown in FIG.

<Formation of transparent electrode layer>
(First step)
As shown in FIG. 2A, a liquid 20A in which metal fine particles are dispersed in an inorganic or organometallic compound dissolved in a solvent is applied to the surface of one surface of the substrate 10 by a spray method. For example, when forming ITO as the transparent electrode layer 20, ITO fine powder having a particle size of 0.1 μm or less dispersed in a solvent, dibutyltin diacetate (DBTDA) and indium acetylacetate (InAA) such as acetylacetone What was dissolved in the organic solvent can be used as the liquid 20 </ b> A applied to the substrate 10. In this case, 2 to 10 percent by weight of tin may be added. The method for applying the liquid is not limited to the spray method, and other methods such as a spin coating method and an ink jet method may be used. The method for applying the liquid is not limited in the following description.

(Second step)
Next, the liquid 20A applied on the substrate 10 in the first step is subjected to heat treatment to generate the precursor 20B of the transparent electrode layer 20. “Precursor” refers to a material in a previous stage for obtaining a specific material. Although the heat treatment conditions depend on the type of solvent, the liquid 20A is dried so that the solvent is removed from the applied liquid 20A at a temperature of 100 to 150 ° C., for example. At this time, heat treatment is performed so that the dissolved or dispersed material in the liquid does not change. Here, the precursor 20B of the transparent electrode layer 20 produced in the second step is lower in hardness and easier to process than the transparent electrode layer 20 formed in the fourth step described later.

(Third step)
Next, as shown in FIG. 2B, the second recess is formed so as to form a recess (line or groove) having a width of several tens of μm by a mechanical method such as scratching or scribing. The precursor 20B of the transparent electrode layer 20 generated in the process is divided. Thereby, since it divides | segments by mechanical methods, such as a scratch and a scribe, the laser apparatus used with the conventional manufacturing method becomes unnecessary. In the case of scratching, it is physically and mechanically scraped off using, for example, a needle, a grinder, a blade or the like. Further, as shown in FIG. 2C, which is a top view (plan view) when FIG. 2B is viewed from the upper side, the formed recesses (lines or grooves) may be only in one direction. Two or more directions may be used. The same applies to the following description.

(4th process)
Next, as illustrated in FIG. 2D, the transparent electrode layer 20 is formed by performing heat treatment on the precursor 20 </ b> B of the transparent electrode layer 20 divided in the third step. In the heat treatment, for example, the precursor 20B of the transparent electrode layer 20 is fired at a temperature of 150 to 400 ° C.

  The inorganic or organometallic compound contained in the liquid 20A applied to the substrate 10 in the first step is indium (In), tin (Sn), zinc (Zn), titanium (Ti), gallium (Ga), tungsten ( Metal compounds containing at least one of W), cerium (Ce), and lead (Pb), particularly indium compounds and tin compounds are preferred. Specifically, tri-i-propoxy indium, indium acetate, indium formate, indium octylate, indium acetyl acetate, basic indium acetate, basic indium octylate, di-n-butyltin acetate, tin acetate, formic acid Tin, octylate, tin acetylacetonate, basic tin acetate, basic octylate, tetra-n-butoxytin, t-butoxytin, Ti alkoxide and other organometallic compounds, indium chloride, indium nitrate, tin chloride, nitric acid Inorganic salts such as tin and zinc chloride can be used. In addition to these, inorganic or organic compounds such as zinc, titanium, gallium, tungsten, and cerium lead may be used. In addition, by mixing several kinds of metals with different ionization numbers, electrons are supplied to balance the electric charge, and the effect of improving the conductivity can be obtained.

  Further, as the solvent of the liquid 20A applied to the substrate 10, a solvent that can be coordinated to the metal and the metal fine particles contained in the inorganic or organic compound and that dissolves the orientation or the organic compound is used. Specifically, ethanol, isopropyl alcohol, N-methylpyrrolidone, NN′-dimethylformamide, NN′-dimethylformamide, toluene, xylene, or the like is used.

<Formation of amorphous silicon layer>
(First step)
3 and 4 are diagrams for explaining a process of forming the amorphous silicon layer shown in FIG. As shown in FIG. 3 (A), polysilane is dissolved in an organic solvent and added (doped) with p-type impurities such as boron and boron, for example, hydrogenated polysilane and a boron compound. The liquid 31A is applied on the transparent electrode layer 20 by spin coating. The liquid 31 </ b> A applied on the transparent electrode layer 20 is obtained by dissolving polysilane in an organic solvent and may be added with a compound serving as a dopant source, such as decaborane. Here, “polysilane” refers to a compound represented by the general formula Si _n H _{2n + 2} (n <2). As a specific example, one having one or more cyclic structures such as cyclopentasilane (Si ₅ H ₁₀ ) is photopolymerized by irradiating with ultraviolet rays to obtain a higher order silane. The same applies to the following description.

(Second step)
Next, the liquid 31A applied on the transparent electrode layer 20 in the first step is subjected to heat treatment to generate a precursor 31B of the p-type amorphous silicon layer 31. The heat treatment conditions depend on the type of solvent, but the liquid 31A is dried so that the solvent is removed from the applied liquid 31A at a temperature of 100 to 150 ° C., for example. At this time, specifically, heat treatment is performed at a temperature at which the material is not amorphized so as not to change what is dissolved or dispersed in the liquid. Here, the precursor 31B of the p-type amorphous silicon layer 31 generated in the second step is low in hardness and easy to process compared to the p-type amorphous silicon layer 31 formed in the fourth step described later. State.

(First step)
Next, as shown in FIG. 3B, a solution obtained by dissolving polysilane in an organic solvent, for example, a liquid 32A containing hydrogenated polysilane is applied onto the precursor 31B of the p-type amorphous silicon layer 31 by spin coating. Apply.

(Second step)
Next, the liquid 32A applied on the precursor 31B of the p-type amorphous silicon layer 31 in the first step is subjected to heat treatment to generate the precursor 32B of the i-type amorphous silicon layer 32. Although the heat treatment conditions depend on the type of solvent, the liquid 32A is dried so that the solvent is removed from the applied liquid 32A at a temperature of 100 to 150 ° C., for example. At this time, specifically, heat treatment is performed at a temperature at which the material is not amorphized so as not to change what is dissolved or dispersed in the liquid. Here, the precursor 32B of the i-type amorphous silicon layer 32 generated in the second step is lower in hardness and easier to process than the i-type amorphous silicon layer 32 formed in the fourth step described later. State.

(First step)
As shown in FIG. 3C, a liquid 33A in which polysilane is dissolved in an organic solvent and doped (doped) with an n-type impurity such as phosphorus is used as a precursor 32B of an i-type amorphous silicon layer 32. It is applied by spin coating. The liquid 33A applied onto the precursor 32B of the i-type amorphous silicon layer 32 is obtained by dissolving polysilane in an organic solvent and adding a compound serving as a dopant source, for example, yellow phosphorus (P ₄ ). It may be.

(Second step)
Next, the liquid 33A applied on the precursor 32B of the i-type amorphous silicon layer 32 in the first step is subjected to heat treatment to generate the precursor 33B of the n-type amorphous silicon layer 33. Although the heat treatment conditions depend on the type of solvent, the liquid 33A is dried so that the solvent is removed from the applied liquid 33A at a temperature of 100 to 150 ° C., for example. At this time, specifically, heat treatment is performed at a temperature at which the material is not amorphized so as not to change what is dissolved or dispersed in the liquid. Here, the precursor 33B of the n-type amorphous silicon layer 33 generated in the second step is lower in hardness and easier to process than the n-type amorphous silicon layer 33 formed in the fourth step described later. State.

(Third step)
Next, as shown in FIG. 4D, p-type so as to form a recess (line or groove) having a width of several tens of μm by a mechanical method such as scratching (cutting) or scribing (cutting). The precursor 31B of the amorphous silicon layer 31, the precursor 32B of the i-type amorphous silicon layer 32, and the precursor 33B of the n-type amorphous silicon layer 33, that is, the precursor 30B of the amorphous silicon layer 30 are divided. In the case of scratching, it is physically and mechanically scraped off using, for example, a needle, a grinder, a blade or the like. Thereby, since it divides | segments by mechanical methods, such as a scratch and a scribe, the laser apparatus used with the conventional manufacturing method becomes unnecessary. 4E is a top view (plan view) of FIG. 4D viewed from above.

(4th process)
Next, as shown in FIG. 4F, the precursor 30B of the amorphous silicon layer 30 divided in the third step is subjected to heat treatment, and a p-type amorphous silicon layer 31, an i-type amorphous silicon layer 32, and an n-type An amorphous silicon layer 33, that is, an amorphous silicon layer 30 is formed. In the heat treatment, for example, the precursor 30B of the amorphous silicon layer 30 is fired at a temperature of 300 to 400 ° C. The thickness of each of the formed amorphous silicon layers 30 is about several tens of nm for the p-type amorphous silicon layer 31, about 300 nm for the i-type amorphous silicon layer 32, and about several tens of nm for the n-type amorphous silicon layer 33. preferable.

In this embodiment, the liquid 31A, 32A, 33A to be applied is a liquid containing polysilane, but other silicon compounds may be polymerized. As the silicon compound, a silicon compound represented by Si _n X _m can be used. Specific examples of the compound where m = 2n + 2 include hydrogenated silanes such as trisilane, tetrasilane, pentasilane, hexasilane, and heptasilane, and those obtained by substituting some or all of these hydrogen atoms with halogen atoms. Specific examples of m = 2n include one ring system such as cyclotrisilane, cyclotetrasilane, the above-mentioned cyclopentasilane, silylcyclopentasilane, cyclohexasilane, silylcyclohexasilane, and cycloheptasilane. Silicon hydride compounds and hexachlorocyclotrisilane, trichlorocyclotrisilane, octachlorocyclotetrasilane, tetrachlorocyclotetrasilane, decachlorocyclopentasilane, pentane in which some or all of these hydrogen atoms are substituted with halogen atoms Chlorcyclopentasilane, dodecachlorocyclohexasilane, hexachlorocyclohexasilane, tetradecachlorocycloheptasilane, heptachlorocycloheptasilane, hexabromocyclotrisilane, tribromocyclotrisilane, penta Lomocyclotrisilane, tetrabromocyclotrisilane, octabromocyclotetrasilane, tetrabromocyclotetrasilane, decabromocyclopentasilane, pentabromocyclopentasilane, dodecabromocyclohexasilane, hexabromocyclohexasilane, tetradecabromo Examples thereof include halogenated cyclic silicon compounds such as cycloheptasilane and heptabromocycloheptasilane. Specific examples of the compound in which m = 2n-2 include 1,1′-biscyclobutasilane, 1,1′-biscyclopentasilane, 1,1′-biscyclohexasilane, 1,1′-bis. Cycloheptasilane, 1,1′-cyclobutasilylcyclopentasilane, 1,1′-cyclobutasilylcyclohexasilane, 1,1′-cyclobutasilylcycloheptasilane, 1,1′-cyclopentasilylcyclohexasilane Lan, 1,1′-cyclopentasilylcycloheptasilane, 1,1′-cyclohexasilylcycloheptasilane, spiro [2,2] pentasilane, spiro [3,3] heptatasilane, spiro [4,4] nonasilane, Spiro [4,5] decasilane, spiro [4,6] undecasilane, spiro [5,5] undecasilane, spiro [5,6] dodecasilane, spiro [6 6] Silicon hydride compounds having two ring systems such as tridecasilane, and silicon compounds in which some or all of these hydrogen atoms are substituted with SiH ₃ groups or halogen atoms. Further, compounds in which m = n, silicon compounds in which some or all of these hydrogen atoms are partially substituted with SiH ₃ groups or halogen atoms, and silicon compounds represented by the general formula Si _a X _b Y _c May be used. These compounds can be used in combination of two or more. In the polymerization, in addition to the ultraviolet rays, heat or other energy rays may be used.

  The solvent is not particularly limited as long as it dissolves a silicon compound and does not react with the solvent. Specific examples include n-hexane, n-heptane, n-octane, n-decane, dicyclopentane, benzene, Hydrocarbon solvents such as toluene, xylene, dilene, indene, tetrahydronaphthalene, decahydronaphthalene, squalane, dipropyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol methyl ethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether , Ethers such as diethylene glycol methyl ethyl ether, tetrahydropyran, 1,2-dimethoxyethane, bis (2-methoxyethyl) ether, p-dioxane Soluble, it can be cited as propylene carbonate, .gamma.-butyrolactone, N- methyl-2-pyrrolidone, dimethyl formamide, acetonitrile, dimethyl sulfoxide, a polar solvent such as chloroform. Of these, hydrocarbon solvents and ether solvents are preferred, and hydrocarbon solvents are more preferred from the viewpoints of solubility in silicon compounds and modified silicon compounds and stability of the solution. These solvents can be used alone or as a mixture of two or more. In particular, a hydrocarbon solvent is preferable from the viewpoint of improving the solubility of the silicon compound and suppressing the residual silicon compound during the heat treatment.

<Formation of zinc oxide layer>
FIG. 5 is a diagram illustrating a process of forming the zinc oxide layer shown in FIG. As shown in the figure, after a liquid in which zinc oxide fine particles are dispersed in a solvent is applied onto the amorphous silicon layer 30 by a spray method, a heat treatment is performed to form a zinc oxide layer 34. Thereby, the zinc oxide layer 34 functions as a reflection enhancing layer that enhances reflection of light transmitted through the substrate 10, the transparent electrode layer 20, and the amorphous silicon layer 30, and is formed on the zinc oxide layer 34, which will be described later. The metal fine particles contained in the back electrode layer 40 act as a diffusion preventing layer that prevents the fine metal particles from diffusing into the n-type amorphous silicon layer 33. In addition, since it is not necessary to process the zinc oxide layer 34, you may form the zinc oxide layer 34 by physical vapor deposition methods, such as a sputtering method and a vapor deposition method, for example.

<Formation of back electrode layer>
(First step)
6 is a diagram for explaining a process of forming the back electrode layer shown in FIG. 1, and FIG. 7 is a diagram for explaining a configuration of a photoelectric conversion device manufactured by a conventional manufacturing method. As shown in FIG. 6 (A), a liquid containing metal fine particles, for example, silver fine particles having a particle size of 100 nm or less, is dispersed in at least one solvent selected from alkylamine, carboxylic acid amide, and aminocarboxylate. The liquid 40A is applied onto the zinc oxide layer 34 by an inkjet method.

(Second step)
Next, the liquid 40A applied on the zinc oxide layer 34 in the first step is subjected to heat treatment to generate the precursor 40B of the back electrode layer 40. Although the heat treatment conditions depend on the type of solvent, the liquid 40A is dried so that the solvent is removed from the applied liquid 40A at a temperature of 25 (room temperature) to 80 ° C., for example. At this time, heat treatment is performed so that the dissolved or dispersed material in the liquid does not change. Here, the precursor 40B of the back electrode layer 40 generated in the second step is in a state of low hardness and easy processing as compared with the back electrode layer 40 formed in the fourth step described later.

(Third step)
Next, as shown in FIG. 6B, the second recess is formed so as to form a recess (line or groove) having a width of several tens of μm by a mechanical method such as scratching (cutting) or scribing (cutting). Only the precursor 40B of the back electrode layer 40 generated in the process is divided. In the case of scratching, it is physically and mechanically scraped off using, for example, a needle, a grinder, a blade or the like. Thereby, since it divides | segments by mechanical methods, such as a scratch and a scribe, the laser apparatus used with the conventional manufacturing method becomes unnecessary. FIG. 6C is a bottom view (plan view) of FIG. 6B viewed from below.

  Here, in the conventional manufacturing method, after the back electrode layer 40 is formed, the back electrode layer 40 is usually divided by irradiation with a YAG laser having a wavelength of 532 nm. In this case, since not only the back electrode layer 40 but also the amorphous silicon layer 30 absorbs the YAG laser, the amorphous silicon layer 30 is also divided and a space S is formed as shown in FIG. As a result, since the substrate 10 and the transparent electrode layer 20 are transparent as shown in FIG. 7B, which is a bottom view (plan view) when FIG. 7A is viewed from below, the amorphous silicon layer 30 and the back electrode Layer 40 is visible. On the other hand, in the manufacturing method of the present invention, since only the precursor 40B of the back electrode layer 40 is divided, the amorphous silicon layer 30 and the precursor 40B of the back electrode layer 40 can be seen as shown in FIG. Thereby, compared with the conventional manufacturing method, the area of the amorphous silicon layer 30 can be increased.

(4th process)
Next, the precursor 40B of the back electrode layer 40 divided in the third step is subjected to heat treatment to form the back electrode layer 40, whereby the photoelectric conversion device 1 shown in FIG. 1 is manufactured. In the heat treatment, for example, the precursor 40B of the back electrode layer 40 is fired at a temperature of 80 to 400 ° C.

  In the present embodiment, as the liquid 40A applied on the zinc oxide film 34, a liquid in which silver fine particles are dispersed in at least one solvent selected from alkylamine, carboxylic acid amide, and aminocarboxylate is used. However, a liquid in which metal fine particles are dispersed in a solution by heating and reducing the metal compound in a solution containing primary and tertiary amines may be used. The tertiary amine contains an alkyl group having 2 or more carbon atoms.

As the tertiary amine, a tertiary amine not containing a methyl group (CH ₃ —), that is, an ethyl group (C ₂ H ₅ —) or a provir group (C ₃ H ₇ —) having 2 or more carbon atoms. A tertiary amine containing an alkyl group is preferred. Examples of the tertiary amine include triethylamine ((C ₂ H ₅ ) 3N), triproviramine ((n-C ₃ H ₇ ) 3N), and triburylamine ((n-C ₄ H ₉ ) 3N). , and the like triamylamine _{((n-C 5 H 11} ) 3N).

The primary amine is preferably an aliphatic primary amine having 8 or more carbon atoms from the viewpoint of the stability of the metal fine particles. Examples of the aliphatic primary amine having 8 or more carbon atoms include octylamine (CH ₃ (CH ₂ ) 7NH ₂ ), nonylamine (CH ₃ (CH ₂ ) 8NH ₂ ), decylamine (CH ₃ (CH ₂ ) 9NH _2), undecyl amine _{(CH 3 (CH 2) 10NH} 2), dodecylamine _{(CH 3 (CH 2) 11NH} 2), tridecyl amine _{(CH 3 (CH 2) 12NH} 2), tetradecyl amine ( CH ₃ (CH ₂ ) 13 NH ₂ ), pentadecylamine (CH ₃ (CH ₂ ) 14 NH ₂ ), cetylamine (CH ₃ (CH ₂ ) 15 NH ₂ ), euleramine (CH ₃ (CH ₂ ) 17 NH ₂ ), etc. be able to.

  The solution containing the primary amine and the tertiary amine is not limited to the reactivity (reducing property) of the primary amine and the tertiary amine as a reducing agent, but other reducing agents such as fatty acids and fatty acids. Metal salts and alcohols may be included, and other organic solvents such as ether solvents such as diethyl ether, ketone solvents such as ethyl methyl ketone and diethyl ketone, and the like may also be included.

  The metal compound is not particularly limited, and carbonates, nitrates, acetates, formates, citrates, oxalates, urates, phthalates or organometallic compounds can be used. Examples of the organometallic compounds include fatty acid metal salts such as naphthenate, octylate, n-decanoate, stearate, benzoate, and paratoluate, metal alkoxides such as isopropoxide and ethoxide, Examples thereof include metal chelate compounds such as metal acetylacetonate.

  In the present embodiment, the transparent electrode layer 20, the p-type amorphous silicon layer 31, the i-type amorphous silicon layer 32, the n-type amorphous silicon layer 33, and the back electrode layer 40 are all formed in the first to fourth steps. However, the present invention is not limited to this, and only one of the layers may be formed.

  As described above, according to the method for manufacturing the photoelectric conversion device 1 according to the present invention, at least one of the transparent electrode layer 20, the amorphous silicon layer 30, and the back electrode layer 40 includes the first step, the second step, and the third step. It is formed by the process and the fourth process. Here, as compared with the layer formed in the fourth step, the precursor of the layer generated in the second step has a low hardness and is easily processed. Further, in the third step, for example, since the division is performed by a mechanical method such as scratching or scribing, the laser device used in the conventional manufacturing method becomes unnecessary. Furthermore, in the fourth step, a layer constituting the photoelectric conversion device 1 is formed by performing heat treatment, so that the vacuum device used in the conventional manufacturing method becomes unnecessary. As a result, it is possible to reduce wrinkles generated when dividing, reduce the number of times a large and expensive device is used, and reduce the manufacturing cost of the photoelectric conversion device 1.

  In addition, at least one of the p-type amorphous silicon layer 31, the i-type amorphous silicon layer 32, and the n-type amorphous silicon layer 33 is formed by the first step, the second step, the third step, and the fourth step. In this case, one or more of the layers constituting the amorphous silicon layer 30 can be formed by using a liquid containing silicon atoms as the liquids 31A, 32A, and 33A.

  The p-type amorphous silicon layer 31 is formed by the first process, the second process, the third process, and the fourth process. In this case, the p-type amorphous silicon layer 31 can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) and a dopant (for example, a boron compound) as the liquid 31A.

  The i-type amorphous silicon layer 32 is formed by the first process, the second process, the third process, and the fourth process. In this case, the i-type amorphous silicon layer 32 can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) as the liquid 32A.

  The n-type amorphous silicon layer 33 is formed by the first process, the second process, the third process, and the fourth process. In this case, the n-type amorphous silicon layer 33 can be formed by using a liquid containing a silane polymer (for example, polysilane hydroxide) and a dopant (for example, a phosphorus compound) as the liquid 33A.

  In addition, since a liquid containing polysilane hydroxide is used as the liquids 31A, 32A, and 33A, a high-quality silicon layer can be obtained.

  In addition, since the zinc oxide layer 34 is formed on the n-type amorphous silicon layer 33, the zinc oxide layer 34 is a reflection that enhances the reflection of light transmitted through the substrate 10, the transparent electrode layer 20, and the amorphous silicon layer 30. In addition to acting as an enhancement layer, it acts as a diffusion prevention layer that prevents metal fine particles contained in the back electrode layer 40 formed on the zinc oxide layer 34 from diffusing into the n-type amorphous silicon layer 33.

  Further, the back electrode layer 40 is formed by the first process, the second process, the third process, and the fourth process, and only the precursor 40B of the back electrode layer 40 is divided in the third process. Here, in the conventional manufacturing method, after forming the back electrode layer 40, the back electrode layer was divided | segmented by irradiating a laser. In this case, since not only the back electrode layer 40 but also the amorphous silicon layer 30 absorbs the laser, the amorphous silicon layer 30 is also divided. On the other hand, in the manufacturing method of the present invention, since only the precursor 40B of the back electrode layer 40 is divided, the area of the amorphous silicon layer 30 can be increased compared to the conventional manufacturing method. Thereby, the photoelectric conversion efficiency of the photoelectric conversion apparatus 1 can be improved.

  In addition, since the substrate 10 and the transparent electrode layer 20 are light transmissive, light incident on the substrate 10 and the transparent electrode layer 20 reaches the amorphous silicon layer 30. Thereby, the light quantity which injects into the amorphous silicon layer 30 can be increased, and the photoelectric conversion efficiency of the photoelectric conversion apparatus 1 can be improved.

  In addition, the structure of this invention is not limited only to the above-mentioned embodiment, You may add a various change within the range which does not deviate from the summary of this invention.

  DESCRIPTION OF SYMBOLS 1 ... Photoelectric conversion apparatus, 10 ... Board | substrate, 20 ... Transparent electrode layer, 30 ... Amorphous silicon layer, 31 ... P-type amorphous silicon layer, 32 ... I-type amorphous silicon layer, 33 ... N-type amorphous silicon layer, 34 ... Zinc oxide Layer, 40 ... back electrode layer, 20A, 31A, 32A, 33A, 40A ... liquid, 20B, 30B, 31B, 32B, 33B, 40B ... precursor.

Claims (9)

A method for manufacturing a photoelectric conversion device comprising: a first electrode layer; a second electrode layer; and a semiconductor layer interposed between the first electrode layer and the second electrode layer,
At least one of the first electrode layer, the semiconductor layer, and the second electrode layer includes a first step of applying a liquid containing a solvent, and a precursor obtained by removing the solvent from the applied liquid. The photoelectric conversion device is manufactured by a second step to be generated, a third step in which the precursor is divided by a mechanical method, and a fourth step in which heat treatment is performed on the divided precursor. Method. As the semiconductor layer, an amorphous silicon layer having a p-type amorphous silicon layer, an i-type amorphous silicon layer, and an n-type amorphous silicon layer is formed,
The liquid contains silicon atoms;
At least one of the p-type amorphous silicon layer, the i-type amorphous silicon layer, and the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. The method for manufacturing a photoelectric conversion device according to claim 1, wherein: The liquid includes a silane polymer and a dopant,
The method for manufacturing a photoelectric conversion device according to claim 2, wherein the p-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. The liquid includes a silane polymer;
The method of manufacturing a photoelectric conversion device according to claim 2, wherein the i-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. The liquid includes a silane polymer and a dopant,
The method for manufacturing a photoelectric conversion device according to claim 2, wherein the n-type amorphous silicon layer is formed by the first step, the second step, the third step, and the fourth step. The method for manufacturing a photoelectric conversion device according to any one of claims 3 to 5, wherein the silane polymer is a polysilane hydroxide. The method for manufacturing a photoelectric conversion device according to any one of claims 2 to 6, further comprising a step of forming a zinc oxide layer on the n-type amorphous silicon layer. The second electrode layer is formed by the first step, the second step, the third step, and the fourth step,
The method for manufacturing a photoelectric conversion device according to any one of claims 1 to 7, wherein in the third step, only the precursor of the second electrode layer is divided. The method for manufacturing a photoelectric conversion device according to any one of claims 1 to 8, wherein the substrate and the first electrode layer have optical transparency.

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