JP6722007B2 - Stacked photoelectric conversion device and manufacturing method thereof - Google Patents

Description

The present invention relates to a stacked photoelectric conversion device including a perovskite cell on a crystalline silicon cell, and a manufacturing method thereof.

In recent years, many reports have been made on the conversion efficiency improvement of a solar cell (perovskite-type solar cell) using an organometallic perovskite crystal. In the production of perovskite solar cells, a method is known in which a porous metal oxide layer such as aluminum oxide or titanium oxide is provided as a scaffold layer for forming a perovskite layer. By coating the perovskite material on the porous scaffold layer, the perovskite material permeates into the pores of the scaffold layer to promote crystal growth and increase the surface area to increase the light absorption amount.

The perovskite crystal material has high spectral sensitivity to light having a wavelength shorter than 800 nm, but hardly absorbs light having a wavelength longer than 800 nm. Therefore, an attempt has been made to stack a top cell having a perovskite layer as a light absorbing layer and a bottom cell having a material having a bandgap narrower than that of a perovskite material as a light absorbing layer to form a multi-junction.

For the multi-junction of the perovskite cell, an intermediate layer for adjusting the band gap and selectively moving carriers (charge transport or charge block) is provided between the bottom cell and the perovskite layer.

Patent Document 1 discloses a perovskite solar cell in which a flat metal oxide layer is used as a scaffold layer and a perovskite layer is provided thereon. Specifically, a solution containing no resin binder is applied, solidification is performed at a low temperature of 150° C. or lower to form a flat metal oxide layer, and a perovskite material is applied thereon to perform metal oxidation. A junction between the material layer and the perovskite layer is formed.

The perovskite cell of Patent Document 1 does not require a high temperature process for forming a metal oxide layer as a scaffold layer, and is therefore useful for forming a stacked photoelectric conversion device in which a perovskite cell is formed on a bottom cell having low heat resistance. .. In Patent Document 1 (see FIG. 16), as an example of multi-junction, a heterojunction type crystalline silicon solar cell having a p-type amorphous silicon-based thin film on the light-receiving surface side of single crystal silicon is used as a bottom cell A laminated solar cell in which a perovskite layer is provided via a flat titanium oxide layer is disclosed. In this configuration, the n-type titanium oxide layer formed by solution coating is expected to act as an intermediate layer that has both the functions of a tunnel junction layer and an electron transport layer.

In Non-Patent Document 1, an ITO/SnO ₂ stack having a function as a tunnel junction layer and an electron transport layer is provided on a crystalline silicon bottom cell in which a p-type diffusion layer is provided on the surface of an n-type single crystal silicon substrate. There is disclosed a stacked photoelectric conversion device provided with a perovskite layer thereon.

WO2014/045021 pamphlet

Steve Albrecht et. al., Energy Environ. Sci. 9, 81-88 (2016)

In forming a heterojunction type crystalline silicon solar cell, a silicon-based thin film is formed on a crystalline silicon substrate by a plasma CVD method. If the formation of the intermediate layer on the silicon-based thin film is performed by the plasma CVD method, the silicon-based thin film and the intermediate layer can be continuously performed by the same device, and thus the production efficiency of the stacked photoelectric conversion device can be improved. Conceivable. However, the titanium oxide intermediate layer disclosed in Patent Document 1 is not suitable for film formation by the plasma CVD method.

The titanium oxide layer as the scaffolding layer of the perovskite layer is formed by solution casting. In the heterojunction type crystalline silicon solar cell, it is common to have a concavo-convex structure with a height of several μm on the light-receiving surface side of the silicon substrate for the purpose of improving the light-trapping efficiency. When the solution film is formed on the bottom cell, liquid is accumulated in the recesses and the film quality becomes non-uniform. Therefore, when the bottom cell has an uneven structure, it is difficult to apply the titanium oxide intermediate layer disclosed in Patent Document 1.

The intermediate layer disclosed in Non-Patent Document 1 is formed of ITO by a sputtering method and SnO ₂ by an atomic layer deposition (ALD) method, and it is possible to form the intermediate layer on a silicon substrate having an uneven structure. is there. However, these materials are also not suitable for film formation by the plasma CVD method. In addition, Non-Patent Document 1 suggests that it is possible to increase the amount of light taken in by the bottom cell by using a material having a higher refractive index instead of the ITO layer positioned on the bottom cell side of the intermediate layer, Microcrystalline silicon having a refractive index of about 4 is described as a candidate for a high refractive index material. However, no consideration has been given to electrical connection with a bottom cell or a top cell when a silicon-based material is used for the intermediate layer.

As disclosed in Patent Document 1 and Non-Patent Document 1, it is considered to be useful to provide an intermediate layer when forming a multi-junction between a bottom cell and a perovskite cell using a crystalline silicon substrate. However, so far, there is little knowledge about the multi-junction of perovskite cells, and no proposals have been made on the material and the laminated structure of the intermediate layer, which are highly feasible from the viewpoint of practicality and mass productivity. In view of the above, it is an object of the present invention to provide a stacked photoelectric conversion device including an intermediate layer suitable for joining a heterojunction type crystalline silicon solar cell and a perovskite solar cell.

The present invention is a heterojunction type crystal having a first conductivity type silicon-based thin film on a first major surface of a single crystal silicon substrate and a second conductivity type silicon-based thin film on a second major surface of a single crystal silicon substrate. The present invention relates to a stacked photoelectric conversion device in which a silicon cell and a perovskite cell having a perovskite light absorption layer are stacked. The stacked photoelectric conversion device of the present invention has a first-conductivity-type silicon-based thin film, a second-conductivity-type intermediate layer, a perovskite light-absorbing layer, and a charge-transporting layer in this order on the first major surface of a single-crystal silicon substrate. Prepare The intermediate layer and the perovskite light absorption layer are in contact with each other. The intermediate layer is a silicon-based thin film, and at least the surface in contact with the perovskite light absorption layer is a silicon alloy containing oxygen or carbon. The intermediate layer preferably contains microcrystalline silicon or a microcrystalline silicon alloy.

The intermediate layer may be a single layer or a laminated structure of two or more layers. When the intermediate layer is a single layer, a material containing microcrystalline silicon or a microcrystalline silicon alloy in an amorphous silicon alloy is preferably used as the material. When the intermediate layer has a laminated structure of two or more layers, the outermost surface layer in contact with the perovskite light absorption layer is a silicon alloy layer. The silicon alloy layer as the outermost surface layer may contain microcrystalline silicon or a microcrystalline silicon alloy. The layer closer to the bottom cell than the outermost surface layer preferably contains microcrystalline silicon or a microcrystalline silicon alloy.

The intermediate layer is preferably formed by the plasma CVD method.

In the stacked photoelectric conversion device of the present invention, since a good junction is formed by forming the perovskite layer on the silicon alloy containing oxygen or carbon, the optical carriers generated in the crystalline silicon bottom cell and the perovskite top cell are formed. Can be taken out effectively.

It is a typical sectional view showing the lamination form of a lamination type photoelectric conversion device. It is a typical sectional view showing the lamination form of a lamination type photoelectric conversion device. It is a typical sectional view showing the lamination form of a lamination type photoelectric conversion device.

FIG. 1 is a schematic cross-sectional view of a stacked photoelectric conversion device according to an embodiment of the present invention. A stacked photoelectric conversion device 101 shown in FIG. 1 includes a perovskite cell 1 as a top cell and a heterojunction crystal silicon cell 2 as a bottom cell from the light incident side, and an intermediate layer between the top cell 1 and the bottom cell 2. 3 is provided. A first electrode 5 is provided on the light incident side of the top cell 1, and a second electrode 6 is provided on the back surface side of the bottom cell 2.

<Heterojunction crystalline silicon cell>
The heterojunction crystal silicon cell 2 includes a first conductivity type silicon-based thin film 24 on the first main surface side of an n-type or p-type single crystal silicon substrate 21, and a first main surface side of the single crystal silicon substrate 21 on the second main surface side. The second conductivity type silicon-based thin film 25 is provided. In the stacked photoelectric conversion device 100, the first conductivity type first main surface side is the light receiving surface.

The conductivity type of the single crystal silicon substrate 21 may be n-type or p-type. When holes and electrons are compared, the mobility of electrons is higher, so that the conversion characteristics are particularly high when the silicon substrate 21 is an n-type single crystal silicon substrate.

The silicon substrate 21 preferably has an uneven structure on the light receiving surface side. Since the silicon substrate 21 has irregularities on the light-receiving surface side, it is possible to reduce reflection of light and increase the amount of light taken into the silicon substrate 21. The uneven structure is formed by, for example, anisotropic etching of crystalline silicon. The height of the irregularities formed on the surface of the silicon substrate 21 is preferably about 0.5 μm to 10 μm.

The silicon-based thin film 24 on the light receiving surface side of the silicon substrate 21 and the silicon-based thin film 25 on the back surface have different conductivity types. That is, one of the silicon-based thin films 24 and 25 is p-type and the other is n-type. As the material of the conductive type silicon-based thin films 24 and 25, amorphous silicon, microcrystalline silicon, amorphous silicon alloy, microcrystalline silicon alloy or the like is used. Examples of the silicon alloy include silicon oxide, silicon carbide, silicon nitride, silicon germanium and the like. Among these, amorphous silicon is preferable. The film thickness of the conductive type silicon-based thin films 24 and 25 is about 3 nm to 50 nm.

Intrinsic silicon based thin films 22 and 23 are preferably provided between the single crystal silicon substrate 21 and the conductive type silicon based thin films 24 and 25. By providing the intrinsic silicon-based thin film on the surface of the single crystal silicon substrate, surface passivation can be effectively performed while suppressing diffusion of impurities into the single crystal silicon substrate. In order to effectively perform the surface passivation of the single crystal silicon substrate 21, the intrinsic silicon-based thin films 22 and 23 are preferably intrinsic amorphous silicon thin films. The film thickness of the intrinsic silicon-based thin films 22 and 23 is about 3 to 16 nm.

As a method for forming the silicon-based thin films 22, 23, 24, 25 on the single crystal silicon substrate 21, a plasma CVD method is preferable. The formation of the silicon-based thin film by the plasma CVD method is performed, for example, under the conditions of a substrate temperature of 100 to 300° C., a pressure of 20 to 2600 Pa, and a high frequency power density of 0.004 to 0.8 W/cm ² . For forming the silicon-based thin film, a silicon-containing gas such as SiH ₄ or Si ₂ H ₆ or a mixed gas obtained by diluting the silicon-containing gas with hydrogen is used as a raw material gas. As a dopant gas for forming the p layer or the n layer, B ₂ H ₆ or PH ₃ is preferably used. A silicon alloy such as silicon carbide, silicon nitride, or silicon germanium can be formed into a film by adding a gas containing a different element such as CH ₄ , CO ₂ , NH ₃ , GeH ₄ to the above gas.

<Perovskite cell>
The perovskite cell 1 contains a photosensitive material having a perovskite crystal structure (perovskite crystal material) as the light absorption layer 11, and includes a charge transport layer 12 on the light receiving surface side of the perovskite light absorption layer 11.

The compound forming the perovskite crystal material is represented by the general formula RNH ₃ MX ₃ or HC(NH ₂ ) ₂ MX ₃ . In the formula, R is an alkyl group, preferably an alkyl group having 1 to 5 carbon atoms, and particularly preferably a methyl group. M is a divalent metal ion, preferably Pb or Sn. X is halogen and includes F, Cl, Br and I. The three Xs may all be the same halogen element, or a plurality of halogens may be mixed. The spectral sensitivity characteristics can be changed by changing the type and ratio of halogen. The perovskite layer can be formed by various dry processes or solution film formation such as spin coating.

The charge transport layer 12 is a hole transport layer or an electron transport layer, and is selected so that the heterojunction crystalline silicon cell 2 and the perovskite cell 1 have the same rectifying direction. That is, when the first conductivity type silicon-based thin film 24 is p-type, the charge transport layer 12 is a hole transport layer, and when the first conductivity-type silicon-based thin film 24 is n-type, the charge transport layer 12 is an electron transport layer. Is.

Examples of the material for the hole transport layer include poly-3-hexylthiophene (P3HT), polythiophene derivatives such as poly(3,4-ethylenedioxythiophene) (PEDOT), and 2,2′,7,7′-. Fluorene derivatives such as tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (Spiro-OMeTAD), carbazole derivatives such as polyvinylcarbazole, triphenylamine derivatives, diphenylamine derivatives, polysilanes Examples thereof include derivatives and polyaniline derivatives. Moreover, metal oxides such as MoO ₃ , WO ₃ , and NiO can also be used as the material of the hole transport layer. Examples of the material of the electron transport layer include metal oxides such as titanium oxide, zinc oxide, niobium oxide, zirconium oxide, and aluminum oxide.

<Middle layer>
The stacked photoelectric conversion device of the present invention includes an intermediate layer 3 between a heterojunction crystal silicon cell 2 and a perovskite cell 1. The intermediate layer 3 is a silicon-based thin film and has a conductivity type different from that of the first conductivity type silicon-based thin film 24. That is, the intermediate layer 3 has the same conductivity type as the second conductivity type silicon-based thin film 25 provided on the second main surface side of the silicon substrate 21. When the first conductivity type silicon-based thin film 24 is p-type, the intermediate layer 3 is n-type, and when the first conductivity-type silicon-based thin film 24 is n-type, the intermediate layer 3 is p-type. Since the first-conductivity-type silicon-based thin film 24 and the intermediate layer 3 have different conductivity types, the intermediate layer 3 acts as a tunnel junction layer between the heterojunction crystalline silicon cell 2 and the perovskite cell 1, and the perovskite layer 11 is formed. Also functions as a charge transport layer.

As described above, the heterojunction crystal silicon cell 2 is particularly excellent in conversion characteristics when the single crystal silicon substrate 21 is n-type. Moreover, the heterojunction crystalline silicon cell 2 is excellent in conversion characteristics when the heterojunction on the light-receiving surface side is a reverse junction. Taken together, in the stacked photoelectric conversion device of the present invention, the silicon substrate 21 is n-type, the first conductivity type silicon-based thin film on the light-receiving surface side is p-type, and the intermediate layer 3 also has an action as an electron transport layer. It is preferable that the charge-transporting layer 12 is a hole-transporting layer.

The film thickness of the intermediate layer 3 is not particularly limited, but 0.5 to 100 nm is preferable, and 5 to 80 nm is more preferable in order to have few defects such as pinholes and to improve the bonding between the top cell and the bottom cell. , 10 to 50 nm is more preferable. The intermediate layer 3 may be a single layer or a laminated structure of two or more layers.

The intermediate layer 3 is in contact with the perovskite light absorption layer 11. At least the surface of the intermediate layer 3 that is in contact with the perovskite light absorption layer is a silicon alloy containing oxygen or carbon. The entire intermediate layer 3 may be a silicon alloy. Examples of the silicon alloy containing oxygen or carbon include silicon oxide, silicon carbide, silicon oxycarbide and the like. The silicon alloy may be hydrogenated.

By forming the perovskite layer in contact with the silicon alloy, the junction between the intermediate layer and the perovskite layer is improved, the intermediate layer effectively functions as a charge transport layer, and the photocurrent extraction efficiency can be improved. When a perovskite layer is formed by solution casting on a non-alloyed silicon layer, the photocurrent extraction efficiency is extremely low. On the other hand, since the silicon alloy has a wider bandgap and higher surface activity than silicon, it is considered that a good junction is formed with the perovskite layer and the photocurrent extraction efficiency is improved.

That is, since the silicon alloy has a wide band gap, it is considered that the silicon alloy acts as a hole blocking layer from the perovskite layer. Further, since a silicon alloy such as silicon oxide has higher wettability (small contact angle) with the perovskite layer forming solution than silicon, it is considered that a good interface is formed.

The intermediate layer 3 preferably contains microcrystalline silicon or a microcrystalline silicon alloy. Since the conductivity of silicon or silicon alloy increases due to crystallization, the series resistance of the intermediate layer 3 as the tunnel junction layer can be reduced and the photocurrent extraction efficiency can be improved.

Since the intermediate layer 3 is a silicon-based thin film, it can be formed by the plasma CVD method. That is, in the fabrication of the stacked photoelectric conversion device of the present invention, both the film formation of the silicon-based thin films 22 and 24 on the silicon substrate 21 and the film formation of the intermediate layer on the silicon-based thin film 24 are performed by plasma. Since it can be carried out by the CVD method, the production efficiency can be improved. Further, when the silicon substrate 21 has irregularities on the light-receiving surface side, it is difficult to uniformly form the intermediate layer by a wet process, whereas the dry process such as plasma CVD is even on the irregular structure. Film formation is possible.

When the intermediate layer 3 is a single layer as shown in FIG. 1, a silicon alloy layer containing a microcrystalline component is formed. The formation of the silicon alloy layer by plasma CVD includes CH ₄ and CO ₂ in addition to the silicon-containing gas such as SiH ₄ and Si ₂ H ₆ as the source gas and B ₂ H ₆ or PH ₃ as the dopant gas. A gas containing a different element is used. Furthermore, it is preferable to introduce hydrogen gas in order to promote crystallization. The amount of hydrogen gas introduced is preferably 10 to 1000 times, and more preferably 50 to 500 times, that of the silicon-containing gas such as SiH ₄ .

In the formation of silicon oxide, it is preferable to adjust the gas introduction amount so that CO ₂ /SiH ₄ is 1 or more. In the formation of silicon carbide, it is preferable to adjust the gas introduction amount so that CH ₄ /SiH ₄ is 1 or more. As the amount of CO ₂ or CH ₄ introduced increases, the band gap of the silicon alloy tends to widen and the refractive index tends to decrease.

On the other hand, different elements such as oxygen and carbon act as crystallization inhibiting elements. Therefore, in order to form a silicon alloy layer containing a microcrystalline component, the introduction amount of the source gas containing a different element is adjusted within the range of CO ₂ /SiH ₄ <10 or CH ₄ /SiH ₄ <3. It is preferable. The film formation of the silicon alloy layer containing the microcrystalline component is performed, for example, under the conditions of a substrate temperature of 150 to 250° C., a pressure of 50 to 1500 Pa, and a high frequency power density of 0.01 to 0.5 W/cm ² .

The silicon alloy layer in contact with the perovskite layer 11 has a refractive index at a wavelength of 600 nm of preferably about 1.7 to 3.5, more preferably about 2.0 to 3.3, and more preferably 2.5 to 3. About 0.0 is more preferable. When the silicon alloy has a refractive index in the above range, a good interfacial bond is formed. When the refractive index is excessively low, the conductivity between the perovskite layer and the intermediate layer tends to decrease due to the decrease in conductivity. If the refractive index is excessively high, the effect of improving the bonding due to alloying may not be fully enjoyed.

As described above, the intermediate layer 3 may have a laminated structure of two or more layers. When the intermediate layer 3 has a laminated structure of two or more layers, the layer in contact with the perovskite layer 11 is a silicon alloy containing oxygen or carbon. The layer provided closer to the bottom cell 2 than the layer adjacent to the perovskite layer 11 preferably contains microcrystalline silicon or a microcrystalline silicon alloy.

FIG. 2 is a schematic cross-sectional view showing one form of a stacked photoelectric conversion device in which the intermediate layer 3 has a two-layer structure. In the stacked photoelectric conversion device 101, the intermediate layer 3 includes a silicon alloy layer 31 as a different surface layer adjacent to the perovskite layer 11, and a base layer 32 provided on the side closer to the bottom cell 2 than the silicon alloy layer 31. 1 has a laminated structure similar to that of the laminated photoelectric conversion device 100 shown in FIG.

When the intermediate layer 3 is composed of a plurality of layers as described above, the silicon alloy layer 31 acts as a scaffolding layer for the perovskite layer 11 formed thereon, and has the action of improving the bondability of the perovskite cell. The base layer 32 on the bottom cell 2 side may be a silicon alloy or silicon. Since the underlayer 32 acts as a tunnel junction layer with the bottom cell 2, it preferably contains a microcrystalline component.

As described above, since oxygen and carbon contained in the silicon alloy act as crystallization inhibiting elements, CVD is required to directly form a silicon alloy layer containing a microcrystalline component on the conductive type silicon-based thin film 24. It is necessary to increase the power density during film formation. When the power density of the CVD film is increased, the silicon-based thin films 24 and 22 and the silicon substrate 21 formed thereunder may be damaged, and the characteristics may be deteriorated due to the diffusion of doped impurities.

On the other hand, when microcrystalline silicon is formed as the underlayer 32 on the conductive type silicon-based thin film 24 and the silicon alloy layer 31 is formed thereon, the underlayer 32 has a power density lower than that of the silicon alloy. Crystallization is possible with. Therefore, damage to the silicon-based thin film of the bottom cell and the silicon substrate can be reduced. Further, since microcrystalline silicon has higher conductivity than silicon alloys such as silicon oxide and silicon carbide, when the underlayer 32 is microcrystalline silicon, the series resistance of the tunnel junction layer is reduced to reduce the photocurrent. The take-out efficiency can be improved.

When the microcrystalline underlayer 32 is provided on the bottom cell 2 side, the silicon alloy layer 31 may be an amorphous film or may contain a microcrystalline component. Since the microcrystalline film is more porous than the amorphous film, when the perovskite layer is formed on the microcrystalline film, the perovskite enters into the crystal grain boundaries to easily form a good junction. Therefore, the silicon alloy layer 31 is also preferably a microcrystalline film containing microcrystalline silicon or a microcrystalline silicon alloy. When the silicon alloy layer 31 is formed on the microcrystalline underlayer 32, the underlayer 32 acts as a nucleus for crystal growth, and thus the crystallization of the silicon alloy layer 31 tends to be promoted.

When the intermediate layer 3 has a two-layer structure including the underlayer 32 and the silicon alloy layer 31, the film thickness of the underlayer 32 is preferably 0.5 to 90 nm, more preferably 5 to 70 nm, even more preferably 10 to 40 nm. The thickness of the silicon alloy layer 31 is preferably 0.5 to 50 nm, more preferably 2 to 40 nm, and further preferably 5 to 30 nm.

The intermediate layer 3 may have a laminated structure of three or more layers. In the stacked photoelectric conversion device 102 illustrated in FIG. 3, the intermediate layer 3 includes a silicon alloy layer 31 adjacent to the perovskite layer 11, a base layer 32 provided closer to the bottom cell 2 than the silicon alloy layer 31, and a lower layer. It has a three-layer structure of a seed layer 33 provided closer to the bottom cell 2 than the formation 32.

By providing the amorphous silicon layer as the seed layer 33, crystallization of the underlayer 32 tends to be promoted, and this tendency is particularly remarkable when the intermediate layer 3 is n-type. Therefore, by depositing an n-type amorphous silicon layer as the seed layer 33 and then depositing n-type microcrystalline silicon as the underlayer 32, a microcrystalline silicon layer having a high crystallization rate even at low power is formed. It can be formed and conductivity can be improved.

From the viewpoint of promoting the formation of microcrystalline silicon, the seed layer 33 preferably has a thickness of 1 nm or more. On the other hand, if the film thickness of amorphous silicon is excessively large, the series resistance may increase and the function as the tunnel junction layer may be hindered. Therefore, the thickness of the seed layer 33 is preferably 1 to 10 nm, more preferably 2 to 8 nm.

<Electrode>
An electrode layer for taking out a photocurrent (photogenerated carrier) to the outside is provided on the light receiving surface side of the top cell 1 and the back surface side of the bottom cell. The configurations of the first electrode 5 on the light receiving surface side and the second electrode 6 on the back surface side are not particularly limited. In order to effectively take out the photogenerated carriers, a laminated structure of a transparent conductive layer and a metal is preferable. When the first electrode 5 has a laminated structure of the transparent conductive layer 51 and the metal electrode 52, the metal electrode 52 is formed in a pattern. When the second electrode has a laminated structure of the transparent conductive layer 61 and the metal electrode 62, the metal electrode 62 may be formed on the entire surface of the transparent conductive layer 61 or may be formed in a pattern.

As a material for the transparent conductive layers 51 and 61, metal oxides such as ITO, zinc oxide and tin oxide are preferably used. The method for forming the transparent conductive layer is not particularly limited, and a dry process such as a CVD method, a sputtering method, an ion plating method, or various wet processes can be adopted. As the metal electrodes 52 and 62, silver, copper, aluminum or the like is preferably used. The method for forming the metal electrode is also not particularly limited. The patterned metal electrode is formed by a method of printing a conductive paste, a plating method, or the like.

In practical use, the photoelectric conversion device of the present invention is preferably modularized by sealing with a sealing material. The photoelectric conversion device is modularized by an appropriate method. For example, adjacent cells are electrically connected in series or in parallel via an interconnector such as a tab, and then sealed with a sealing material and a glass plate.

1 Perovskite cell (top cell)
11 Perovskite layer 12 Charge transport layer 2 Crystal silicon cell (bottom cell)
21 Single Crystal Silicon Substrate 22,23 Intrinsic Silicon Thin Film 24,25 Conductive Silicon Thin Film 3 Intermediate Layer 31 Silicon Alloy Layer 32 Underlayer (Microcrystalline Silicon Layer)
33 Seed layer (amorphous silicon layer)
5,6 electrodes

Claims (6)

Crystal silicon including a single crystal silicon substrate, a first conductivity type silicon-based thin film on the first main surface of the single crystal silicon substrate, and a second conductivity type silicon-based thin film on the second main surface of the single crystal silicon substrate A stacked photoelectric conversion device in which a cell and a perovskite cell including a perovskite light absorption layer and a charge transport layer are stacked,
On the first main surface of the single crystal silicon substrate, the first conductivity type silicon-based thin film, a second conductivity type intermediate layer, the perovskite light absorption layer, and the charge transport layer in this order,
The intermediate layer and the perovskite light absorption layer are in contact with each other,
The stacked photoelectric conversion device, wherein the intermediate layer is a silicon-based thin film, contains microcrystalline silicon or a microcrystalline silicon alloy, and at least a surface in contact with the perovskite light absorption layer is a silicon alloy containing oxygen or carbon. The intermediate layer is composed of a plurality of silicon-based thin film,
The intermediate layer, the outermost surface layer in contact with the perovskite light absorption layer is a silicon alloy containing oxygen or carbon, and contains microcrystalline silicon or a microcrystalline silicon alloy on the side closer to the crystalline silicon cell than the outermost surface layer. The stacked photoelectric conversion device according to claim 1 , further comprising: The stacked photoelectric conversion device according to claim 2 , wherein the intermediate layer has a microcrystalline silicon layer in contact with the surface of the outermost surface layer on the side of the crystalline silicon cell. The microcrystalline silicon layer, in contact with the first conductive-type silicon-based or thin film is in contact, or amorphous silicon layer provided in contact with the first conductivity type silicon-based thin film, according to claim 3 Stacked photoelectric conversion device. The single crystal silicon substrate has an uneven surface of the first main surface side, stacked photoelectric conversion device according to any one of claims 1-4. A method of producing a stacked photoelectric conversion device according to any one of claims 1 to 5
A method for manufacturing a stacked photoelectric conversion device, wherein the intermediate layer is formed by a plasma CVD method.

Images