JP2009260209A - Laminated photoelectric converter and photoelectric conversion module - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a laminated photoelectric converter whose photoelectric conversion efficiency is improved. <P>SOLUTION: The laminated photoelectric converter 1 has: a translucent photoelectric conversion layer 3 having a non-single crystal semiconductor layer; a translucent recombination layer 4 for recombining an electron with a positive hole, formed on the translucent photoelectric conversion layer 3; and an organic photoelectric conversion layer 4 including an organic semiconductor, formed on the translucent recombination layer 4. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a stacked (tandem) photoelectric conversion device and a photoelectric conversion module in which a plurality of types of photoelectric conversion layers are stacked, in which a high photoelectric conversion efficiency is obtained, excellent weather resistance, and can be manufactured at low cost. The present invention relates to a photoelectric conversion device and a photoelectric conversion module.

  In the organic photoelectric conversion layer, most of the elements constituting the organic photoelectric conversion layer are made of carbon, hydrogen, nitrogen, sulfur, etc., and there are few restrictions on raw materials. Furthermore, since it can be formed by a low temperature process of room temperature to about 150 ° C., there is an advantage that a plastic substrate or the like can be used.

  As a method for improving the photoelectric conversion efficiency (hereinafter also referred to as “conversion efficiency”) of the organic photoelectric conversion layer, a method for improving the mobility of charges and electrons in the organic semiconductor (hereinafter also simply referred to as “mobility”), There are a method for suppressing deactivation (inactivation) of excitons in the electrode and a method for increasing the area of the interface between the p-type organic semiconductor and the n-type organic semiconductor.

  As a method for improving the mobility of the organic semiconductor, there is a method of increasing the crystallinity of the organic semiconductor by annealing. As a result, the mobility is improved and the spectral sensitivity can be obtained on the longer wavelength side from the change in the absorption spectrum due to the change in crystallinity, and the short-circuit current density is improved.

  As a method for suppressing the deactivation of excitons in the electrode, a hole blocking layer such as bathocuproine (BCP), polyethylenedioxythiophene (PEDOT: Poly (3,4-ethylenedioxythiophene): poly-styrenesulfonate), electron There is a method of inserting a block layer between an organic semiconductor layer and an electrode layer. Thereby, a short circuit current density and a fill factor improve. When the hole block layer and the electron block layer are not inserted, excitons are deactivated by metal particles that have penetrated the electrode or the organic semiconductor, resulting in an increase in apparent internal resistance and loss of short-circuit current density.

  As a method of increasing the area of the interface between the p-type organic semiconductor and the n-type organic semiconductor, there are a method of co-evaporating the p-type organic semiconductor and the n-type organic semiconductor, a method of performing an annealing treatment after the formation of the organic photoelectric conversion layer, and the like. As a result, the junction interface between the p-type organic semiconductor and the n-type organic semiconductor increases, and the area of the interface where charge separation of the generated excitons can be increased. As a result, the short circuit current density can be increased. A layer in which a p-type organic semiconductor and an n-type organic semiconductor are co-evaporated is called an i layer and greatly affects the increase in current density. Further, the p-type organic semiconductor and the n-type organic semiconductor are dissolved in one solvent, spin-coated, and annealed after the formation of the organic photoelectric conversion device, whereby the p-type organic semiconductor and the n-type organic semiconductor are phase-separated, As a result, since the area of the interface between the p-type organic semiconductor and the n-type organic semiconductor is improved, the short-circuit current density is improved.

Further, Patent Document 1 discloses a photoelectric conversion element in which an organic semiconductor and an inorganic semiconductor are stacked. This photoelectric conversion element is configured by sequentially stacking a p-type organic semiconductor layer, a fullerene layer, and a back electrode on a transparent electrode on a transparent substrate. In the photoelectric conversion element of Patent Document 1, a p-type organic semiconductor facing sunlight and a fullerene layer stacked thereon generate excitons from incident light, and charge is generated at the interface between the p-type organic semiconductor and the fullerene layer. Separation is performed, and holes are transported by a p-type organic semiconductor and electrons are transported by a fullerene layer.
JP-A-5-335614

  In the organic photoelectric conversion element described in Patent Document 1, the shape of the interface between the p-type inorganic semiconductor and the fullerene that is an organic semiconductor is difficult to control, and the low mobility of the organic semiconductor is increased or the exciton is deactivated. It was difficult to suppress, and the photoelectric conversion efficiency could be reduced.

  The present invention has been completed in view of the above conventional problems, and an object thereof is to obtain a stacked photoelectric conversion device with improved photoelectric conversion efficiency.

The stacked photoelectric conversion device of the present invention includes a translucent photoelectric conversion layer having a non-single-crystal semiconductor layer,
A translucent recombination layer formed on the translucent photoelectric conversion layer for recombining electrons and holes;
And an organic photoelectric conversion layer including an organic semiconductor formed on the translucent recombination layer.

  The stacked photoelectric conversion device of the present invention is preferably characterized in that the peak wavelength of the spectral sensitivity of the organic photoelectric conversion layer is longer than the peak wavelength of the spectral sensitivity of the translucent photoelectric conversion layer. To do.

  In addition, the stacked photoelectric conversion device of the present invention is preferably characterized in that the organic photoelectric conversion layer has a spectral sensitivity to the transmitted light of the translucent photoelectric conversion layer.

  Moreover, the stacked photoelectric conversion device of the present invention is preferably characterized in that the translucent photoelectric conversion layer has a pin structure including an i-type amorphous silicon layer.

  In the stacked photoelectric conversion device according to the present invention, preferably, the translucent recombination layer includes at least one of a metal, a conductive oxide, and a conductive polymer.

  In the stacked photoelectric conversion device of the present invention, it is preferable that the translucent recombination layer is composed of island-shaped portions made of a plurality of independent metals.

  In the stacked photoelectric conversion device of the present invention, preferably, the translucent recombination layer has a plurality of through holes.

  In the stacked photoelectric conversion device of the present invention, preferably, the translucent recombination layer includes a catalyst layer.

In the stacked photoelectric conversion device of the present invention, preferably, the translucent recombination layer includes the first catalyst layer in contact with the organic photoelectric conversion layer and the translucent photoelectric conversion layer. An intermediate layer including a second catalyst layer in contact therewith and interposed between the first catalyst layer and the second catalyst layer, wherein the surface resistivity of the intermediate layer is 1.0 × 10 ³ Ω / □ or more and 1.0 × 10 ¹⁰ Ω / □ or less.

  In the stacked photoelectric conversion device of the present invention, preferably, the catalyst layer contains at least one of platinum, palladium, nickel, aluminum, and silver.

  The photoelectric conversion module of the present invention is one in which a plurality of stacked photoelectric conversion devices of the present invention are arranged in the horizontal direction and are electrically connected.

  According to the stacked photoelectric conversion device of the present invention, by providing a translucent recombination layer that recombines electrons and holes between an organic photoelectric conversion layer and a translucent photoelectric conversion layer, The electrons (or holes) extracted from the system photoelectric conversion layer and the holes (or electrons) extracted from the translucent photoelectric conversion layer can be efficiently recombined. As a result, according to the stacked photoelectric conversion device of the present invention, the holes (or electrons) extracted from the organic photoelectric conversion layer and the electrons (or holes) extracted from the translucent photoelectric conversion layer are efficiently converted. Since it can often be taken out of the photoelectric conversion device, the photoelectric conversion efficiency can be increased.

In addition, the stacked photoelectric conversion device of the present invention preferably has a peak wavelength of the spectral sensitivity of the organic photoelectric conversion layer on the longer wavelength side than the peak wavelength of the spectral sensitivity of the translucent photoelectric conversion layer. The conversion layer and the translucent photoelectric conversion layer can efficiently photoelectrically convert light in different wavelength ranges, and high conversion efficiency can be obtained.

  In the stacked photoelectric conversion device of the present invention, preferably, the translucent photoelectric conversion layer has a pin structure including an i-type amorphous silicon layer, and thus the translucent photoelectric conversion layer has a thickness of about 700 nm. It absorbs the following short wavelength light and generates electric power, and transmits long wavelength light of about 700 nm or more. As a result, for example, light in a wavelength region that can be sufficiently absorbed and generated by the organic photoelectric conversion layer disposed on the rear side of the translucent photoelectric conversion layer is transmitted. The wavelength range of sunlight is 310 nm to 2000 nm, and the wavelength range with high intensity is 400 nm to 1200 nm. Therefore, sufficient conversion efficiency can be obtained by using an organic semiconductor having sensitivity at 700 nm to 1200 nm or 700 nm to 2000 nm for the organic photoelectric conversion layer.

  In the stacked photoelectric conversion device of the present invention, preferably, the translucent recombination layer includes at least one of a metal, a conductive oxide, and a conductive polymer. And a translucent recombination layer with low light loss can be obtained.

  In the stacked photoelectric conversion device of the present invention, preferably, the translucent recombination layer is composed of island-shaped portions made of a plurality of metals independent from each other, so that an excellent translucency can be obtained. There is an advantage that it can be used as a growth nucleus of the organic photoelectric conversion layer to be laminated next. In this case, the work function between the translucent photoelectric conversion layer and the organic photoelectric conversion layer is reduced, and electrons and charges are transferred between the translucent photoelectric conversion layer and the organic photoelectric conversion layer. Becomes easier.

  In the stacked photoelectric conversion device of the present invention, preferably, the light-transmitting recombination layer has a plurality of through-holes. There is an advantage that it can be used as a growth nucleus of an organic photoelectric conversion layer. In this case, the electron work function between the translucent photoelectric conversion layer and the organic photoelectric conversion layer is reduced by reducing the electron work function between the translucent photoelectric conversion layer and the organic photoelectric conversion layer. Is easy to move.

  Moreover, in the stacked photoelectric conversion device of the present invention, if a catalyst layer is provided in the translucent recombination layer, overvoltage acting on the organic photoelectric conversion layer and the translucent photoelectric conversion layer can be reduced. The overvoltage required for charge recombination can be reduced.

In the stacked photoelectric conversion device of the present invention, the translucent recombination layer includes a first catalyst layer in contact with the organic photoelectric conversion layer and a first photoelectric layer in contact with the organic photoelectric conversion layer. And an intermediate layer interposed between the first catalyst layer and the second catalyst layer, the surface resistivity of the intermediate layer being 1.0 × 10 ³ Ω / If it is □ or more and 1.0 × 10 ¹⁰ Ω or less, the movement of charges in the in-plane direction of the intermediate layer is suppressed while realizing the recombination of charges between the translucent photoelectric conversion layer and the organic photoelectric conversion layer. In addition, since recombination of charges in the translucent photoelectric conversion layer can be reduced, the photoelectric conversion efficiency can be further increased.

  In the stacked photoelectric conversion device of the present invention, if the catalyst layer includes at least one of platinum, palladium, nickel, aluminum, and silver, the catalytic action for reducing overvoltage can be further enhanced. it can.

  The photoelectric conversion module of the present invention includes a stacked photoelectric conversion device having a high photoelectric conversion efficiency because a plurality of stacked photoelectric conversion devices of the present invention are arranged in the horizontal direction and are electrically connected. Since a plurality of electrical connections are made, a photoelectric conversion module having a large photocurrent output is obtained.

  Specific examples of the photoelectric conversion device of this embodiment will be described below in detail with reference to the drawings.

  An example of the embodiment of the stacked photoelectric conversion device of this embodiment is shown in a cross-sectional view of FIG.

  The stacked photoelectric conversion device according to the present embodiment includes a light-transmitting photoelectric conversion layer 3 having a non-single-crystal semiconductor layer, and a light-transmitting layer that recombines electrons and holes formed on the light-transmitting photoelectric conversion layer 3. It has the optical recombination layer 4 and the organic photoelectric conversion layer 2 containing the organic semiconductor formed on the translucent recombination layer 4.

  The stacked photoelectric conversion device 1 of FIG. 1 having a more specific configuration includes a light-transmitting photoelectric conversion layer 3 having a light-transmitting substrate 31a and a non-single-crystal semiconductor layer formed on the light-transmitting substrate 31a. An organic photoelectric including a translucent recombination layer 4 that recombines electrons and holes formed on the translucent photoelectric conversion layer 3, and an organic semiconductor formed on the translucent recombination layer 4. A conversion layer 2. Note that a light-transmitting conductive layer 31b is formed on the light-transmitting substrate 31a, and the conductive substrate 31 is configured by combining them.

  In the photoelectric conversion device of the present embodiment, the translucent substrate 31a may not be provided, and in that case, the translucent photoelectric conversion layer 3 itself may be formed of a hard plate. Further, the light-transmitting conductive layer 31b may not be provided, and in that case, a collector electrode or the like may be provided at an end of the light-transmitting photoelectric conversion layer 3. Further, when there are the light-transmitting substrate 31a and the light-transmitting conductive layer 31b, the light-transmitting substrate 31a functions as a support and a light transmitting body for the light-transmitting photoelectric conversion layer 3, and the light-transmitting conductive layer 31b is transparent. This is preferable in that it functions as a light-sensitive large-area electrode.

  Moreover, the translucent photoelectric conversion layer 3 should just produce internal electric fields, such as a pn junction type, a Schottky junction type, and a hetero junction type other than a pin junction type.

  The organic photoelectric conversion layer 2 only needs to generate an internal electric field such as a pin junction type, a pn junction type, a bulk hetero type, or a superlattice type. As an example in FIG. 1, from the translucent recombination layer 4 side, a first conductive type (p-type) organic semiconductor layer 24, a dye layer 23, a second conductive type (n-type) organic semiconductor layer 22, A configuration including the hole blocking layer 21 is shown.

  The organic photoelectric conversion layer 2 can be used by repeatedly laminating 2-3 layers in order to compensate for low mobility. In addition, in order to match the current with the organic photoelectric conversion layer 2, the spectral sensitivity can be adjusted by thinning the translucent photoelectric conversion layer 3, or the translucent photoelectric conversion layer 3 can be repeatedly laminated. . In this case, higher conversion efficiency can be achieved by inserting the translucent recombination layer 4 between the photoelectric conversion layers.

  FIG. 6 shows a cross-sectional view of a photoelectric conversion module 10 obtained by modularizing the stacked photoelectric conversion device 1 of FIG. In the photoelectric conversion module 10, a plurality of the stacked photoelectric conversion devices 1 of the present embodiment are arranged in the horizontal direction and are electrically connected. FIG. 6 shows a unit body of the stacked photoelectric conversion device 1. A plurality of the unit bodies are arranged in the horizontal direction, and these units are connected in series, in parallel, or in series and parallel to form the photoelectric conversion module 10. .

  The structure and manufacturing method of the photoelectric conversion module 10 of this Embodiment are demonstrated below.

  First, the translucent conductive layer 31b is divided by laser scribing to separate the positive electrode (p) and the negative electrode (n), the translucent photoelectric conversion layer 3, the translucent recombination layer 4, and the organic photoelectric conversion layer. After stacking 2, the electrode 5 is patterned and drawn out to the organic photoelectric conversion layer 3 side (lower side). 31bb is a parting part of the translucent conductive layer 31b. The lower end portion of the electrode 5 is connected to the translucent conductive layer 31 b that is an electrode on the positive electrode side of the adjacent stacked photoelectric conversion device 1.

  In addition, an insulating layer (not shown) is provided at a portion of the organic photoelectric conversion layer 2, the translucent recombination layer 4, and the translucent photoelectric conversion layer 3 that is in contact with the electrode 5 so as not to be electrically connected to the electrode 5. May be formed. Or since the organic type photoelectric converting layer 2, the translucent recombination layer 4, and the translucent photoelectric converting layer 3 are comparatively high resistance, the insulating layer does not need to be formed.

  Next, the outer peripheral portion of the lower surface of the counter substrate 7 and the outer peripheral portion of the upper surface of the conductive substrate 31 are bonded together by the sealing material 6. At this time, the space inside the sealing material 6 is in a vacuum state, a reduced pressure state, an inert gas sealed state, and the like, and oxidation by oxygen and water is suppressed.

  The electrode 5 is formed by a vapor deposition method, a sputtering method, a printing method, or the like using a mask.

  The sealing material 6 is made of glass frit, epoxy resin, ionomer, or the like. The sealing material 6 can be formed by a printing method, a thermocompression bonding method, an ultraviolet curing method, or the like. However, in order to suppress deterioration of the organic photoelectric conversion layer 2, it is preferably performed in a dark place at as low a temperature as possible. When heat and light affect the organic photoelectric conversion layer 2, the atmosphere gas during the assembly operation may be an inert gas, or the assembly operation may be performed in a reduced pressure state or a vacuum state, in which case the organic photoelectric conversion is performed. Deterioration of the layer 2 is suppressed.

  The counter substrate 7 is made of glass, metal, plastic or the like. In the case of using the counter substrate 7 made of plastic, it is preferable to use a substrate in which a gas barrier coat made of a metal layer or the like is formed on the surface in order to suppress oxygen and moisture permeability. The gas barrier coat is formed by a vapor deposition method or the like.

  FIG. 7 shows a cross-sectional view of another example of the photoelectric conversion module 10 obtained by modularizing the stacked photoelectric conversion device 1 of FIG. The photoelectric conversion module of FIG. 7 has a configuration in which a laminated body in which a light-transmissive photoelectric conversion layer 3, a light-transmissive recombination layer 4, and an organic photoelectric conversion layer 2 are stacked is embedded in a sealing material 6. The configuration of other parts is the same as that of the photoelectric conversion module 10 of FIG.

  It is preferable that no air pocket remains inside the sealing material 6 as much as possible. However, in order to relieve stress generated due to a difference in thermal expansion coefficient between the counter substrate 7 and the conductive substrate 31, it is preferable to leave some bubbles.

  Moreover, since the sealing material 6 needs to cover the laminated body which laminated | stacked the translucent photoelectric converting layer 3, the translucent recombination layer 4, and the organic type photoelectric converting layer 2, it is liquid etc. before covering a laminated body. It is preferable that the material is flexible and is cured by heat treatment and ultraviolet irradiation after covering the laminate.

  FIG. 8 is a cross-sectional view of another example of the photoelectric conversion module 10 obtained by modularizing the stacked photoelectric conversion device 1 of FIG. The photoelectric conversion module 10 in FIG. 8 does not have the counter substrate 7, and the configuration of other parts is the same as that of the photoelectric conversion module 10 in FIG.

In order to suppress the permeability of oxygen and moisture, the sealing material 6 is preferably used in which a gas barrier coat made of a metal layer or the like is formed on the surface. The gas barrier coat is formed by a vapor deposition method or the like. Moreover, the sealing material 6 can also be covered with the back sheet for improving moisture resistance.

  In addition, the stacked photoelectric conversion device of the present embodiment includes a conductive substrate, an organic photoelectric conversion layer 2 including an organic semiconductor formed on the conductive substrate, and an electron formed on the organic photoelectric conversion layer. A translucent recombination layer 4 for recombining holes with holes, and a translucent photoelectric conversion layer 3 having a non-single-crystal semiconductor layer formed on the translucent recombination layer 4 (not shown). ).

  In this case, if the conductive substrate is a non-translucent substrate, light is incident from the translucent photoelectric conversion layer 3 side, whereby short-wavelength light (wavelength 300) is generated in the thin-film translucent photoelectric conversion layer 3. Is highly photoelectrically converted, long-wavelength light (wavelength of about 600 to 900 nm) is well photoelectrically converted in the organic photoelectric conversion layer 2, and high conversion efficiency is obtained by combining the conversion efficiencies of both the photoelectric conversion layers 2 and 3. can get.

  Hereinafter, each component of the stacked photoelectric conversion device 1 will be described in detail.

<Conductive substrate (translucent substrate)>
The conductive substrate 31 includes a translucent substrate 31a and a translucent conductive layer 31b. As a material of the translucent substrate 31a, resin such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), polyimide, polycarbonate, inorganic material such as blue plate glass, soda glass, borosilicate glass, ceramics, or conductive resin Organic-inorganic hybrid materials are good.

As the translucent conductive layer 31b, a tin-doped indium oxide layer (ITO layer), an impurity-doped indium oxide layer (In ₂ O ₃ layer), or the like formed by a low-temperature growth sputtering method, a low-temperature spray pyrolysis method, or the like is preferable. . Further, a fluorine-doped tin dioxide layer (SnO ₂ : F layer) formed by a thermal CVD method, an impurity-doped zinc oxide layer (ZnO layer) formed by a solution growth method, or the like may be used. Further, these layers may be stacked and used.

  Other methods for forming the translucent conductive layer 31b include a vacuum deposition method, an ion plating method, a dip coating method, and a sol-gel method. Further, if a surface irregularity in the order of the wavelength of incident light is formed on the surface of the translucent conductive layer 31b, a light confinement effect may be obtained.

  The translucent conductive layer 31b may be a thin (about 1 to 5 nm thick) metal layer made of Au, Pd, Al, or the like formed by a vacuum deposition method, a sputtering method, or the like.

  The thickness of the conductive substrate 31 is preferably 0.1 mm to 5 mm, more preferably 0.2 mm to 3 mm. By setting it within the range of 0.1 mm to 5 mm, the mechanical strength of the conductive substrate 31 can be made sufficient, and an increase in weight can be suppressed.

  The thickness of the translucent conductive layer 31b is preferably 0.001 μm to 10 μm, more preferably 0.05 μm to 2 μm. By setting it within the range of 0.001 μm to 10 μm, the conductivity and light transmittance of the translucent conductive layer 31 b can be maintained high.

  Further, when an antireflection film such as a dielectric multilayer film is formed on the light incident surface of the conductive substrate 31 (the surface on the white arrow side in FIG. 1), the amount of incident light may be increased. In addition, the white arrow of FIG. 1 shows incident light.

<Organic photoelectric conversion layer>
The organic photoelectric conversion layer 2 only needs to generate an internal electric field such as a pin junction type, a pn junction type, a bulk hetero type, or a superlattice type.

  Examples of the organic semiconductor material constituting the organic photoelectric conversion layer 2 include phthalocyanine semiconductors such as phthalocyanine, zinc phthalocyanine, copper phthalocyanine, titanyl phthalocyanine, vanadyl phthalocyanine, hexadecafluorozinc phthalocyanine, and chlorophthalocyanine, C60, C70, and fullerene oxide. , Phenyl C61 butyl acid methyl ester (PCBM), phenyl C85 butyl acid methyl ester ([84] PCBM), fullerene semiconductors such as fullerene derivatives, porphyrin semiconductors such as tetramethylporphyrin, bacteriochlorophylls, chlorophylls, pentacene, Polyacene semiconductors such as tetracene, thiophene semiconductors such as poly-3-hexylthiophene, naphthalene semiconductors, pyrrole semiconductors Quinone semiconductors such as benzoquinone and naphthoquinone, TCNQ semiconductors such as tetracyanoquinodimethane (TCNQ) and tetrafluorotetracyanoquinodimethane, and perylene semiconductors such as perylene and perylenetetracarboxylic acid, which are amorphous. It can be used as a polycrystalline phase or a single crystal phase. In addition, the material having the above-described composition can also be used as a derivative or a polymer imparted with an electron withdrawing property, electron donating property, stability, and the like by a functional group.

  The organic photoelectric conversion layer can also be used as a doping or charge transfer complex. For example, tetracyanoquinodimethane can be used as a p-type dopant for metal phthalocyanine, and Mg or tetrafluorotetracyanoquinodimethane (F4-TCNQ) can be used as an n-type dopant. Alternatively, a charge transfer complex in which tetrathiafuvalene (TTF) is coordinated with TCNQ can be used. By doping in this way, the conductivity can be increased to improve the mobility, and the film thickness can be increased. Further, the open band voltage of the organic photoelectric conversion layer can be increased by controlling the levels of the conduction band and the valence band by doping.

  If the charge separation property with the organic semiconductor is good, the semiconductor constituting the organic photoelectric conversion layer 2 is a chalcopyrite compound semiconductor, a silicon semiconductor, a group 2-6 semiconductor such as zinc oxide, indium nitride, or the like. Alternatively, a group 3-5 semiconductor may be used. In particular, chalcopyrite compound semiconductors have long wavelength sensitivity and are suitable as a dye layer. As a method of using such an organic semiconductor and an inorganic semiconductor, a method of using a chalcopyrite compound semiconductor fine particle in a bulk hetero organic photoelectric conversion layer and using it as a semiconductor dye, a surface having a flat surface or an uneven shape A method of forming a pn interface by coating P3HT (poly-3-hexylthiophene), which is a p-type semiconductor, on the formed n-type zinc oxide semiconductor, and a bulk hetero layer (mixed film of P3HT and PCBM) on the n-type zinc oxide semiconductor A method of coating and exhibiting the function as a hole blocking layer simultaneously with the formation of the pn interface is preferable.

  In addition, as described above, inorganic metal oxides such as TiOx, NbOx, ZrOx, TaOx, and WOx can be cited as materials that exhibit the function as the hole blocking layer. Here, by including a part of the amorphous structure, coverage is improved and reliability is improved.

  The dye layer shown in FIG. 1 refers to a layer having a function of photoelectric conversion and capable of transferring charges to and from a semiconductor layer in contact therewith. Here, the charge refers to a charge generated by the generated exciton by charge separation at the interface between the dye layer and the semiconductor layer, a charge separated by charge inside the dye, or the like.

  As shown in FIG. 2, the pin junction type means an electron block layer 25, a first conductivity type (p-type) organic semiconductor layer 24a, a first conductivity type (p-type) organic semiconductor, and a second conductivity type (n Type) organic semiconductor mixed (i-type) layer 23a, second conductive type (n-type) organic semiconductor 22a, and hole blocking layer 21a are sequentially stacked.

  As shown in FIG. 3, the pn junction type means an electron block layer 25a, a first conductivity type (p type) organic semiconductor layer 24b, a second conductivity type (n type) organic semiconductor layer 22b, and a hole block layer. In this configuration, 21b is sequentially stacked.

  As shown in FIG. 4, the bulk hetero type has a configuration in which an electron block layer 25b, a bulk hetero layer 26, and a hole block layer 21c are sequentially stacked. This bulk hetero type can promote the layer separation in the bulk hetero layer 26 and the crystallization of the organic semiconductor by performing an annealing process, and as a result, the conversion efficiency can be improved. Further, the spectral sensitivity can be improved by further mixing the dye into the bulk hetero layer 26.

  As shown in FIG. 5, the superlattice type includes three groups of an electron block layer 25b, a first conductivity type (p-type) organic semiconductor layer 24d, and a second conductivity type (n-type) organic semiconductor layer 22d. The stacked structure layer and the hole blocking layer 21d are sequentially stacked.

  The organic photoelectric conversion layer 2 is formed by a vacuum evaporation method, a spin coating method, a dip coating method, a casting method, a printing method, an ink jet method, a physical vapor deposition method, or the like.

  In the configuration of FIG. 1, the first conductivity type (p-type) organic semiconductor layer 24 is preferably made of copper phthalocyanine or the like and has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage (coverage) of the first conductive type organic semiconductor layer 24 is improved, the charge separation is sufficient, and the increase in series resistance is suppressed. Can do.

  The dye layer 23 is a layer that increases spectral sensitivity without affecting the charge separation, and is made of tin phthalocyanine or the like, and preferably has a thickness of about 0.5 nm to 50 nm. By setting it within the range of about 0.5 nm to 50 nm, the spectral sensitivity can be increased, and the series resistance can be reduced.

  The second conductivity type (n-type) organic semiconductor layer 22 is made of fullerene C60 or the like and preferably has a thickness of about 0.5 nm to 200 nm. By setting the thickness within the range of about 0.5 nm to 200 nm, the coverage of the second conductive type organic semiconductor layer 22 is improved, the charge separation is sufficient, and the increase in series resistance can be suppressed. it can.

  The hole blocking layer 21 is made of bathocuproine, TiOx (titanium oxide layer including an amorphous structure), or the like, and preferably has a thickness of about 0.5 nm to 1000 nm. By setting the thickness within the range of about 0.5 nm to 1000 nm, the coverage of the hole blocking layer 21 is improved, the charge separation is sufficient, and the increase in series resistance can be suppressed.

  In the configuration of FIG. 2, the electron block layer 25 is made of PEDOT: PSS or the like and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the electron blocking layer 25 is improved, charge separation is sufficient, and further, increase in series resistance can be suppressed.

  The first conductivity type (p-type) organic semiconductor layer 24a is made of copper phthalocyanine or the like, and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the first conductive type (p-type) organic semiconductor layer 24a is improved, charge separation is sufficient, and further, the increase in series resistance is suppressed. be able to.

  The mixed layer 23a is made of copper phthalocyanine, fullerene C60, and the like, and the thickness is preferably about 1 to 500 nm. By setting it within the range of about 1 to 500 nm, the spectral sensitivity can be increased and the series resistance can be reduced.

The second conductivity type (n-type) organic semiconductor layer 22a is made of fullerene C60 or the like and has a thickness of 0.
. It is good that it is about 5 nm-200 nm. By setting the thickness within the range of about 0.5 nm to 200 nm, the coverage of the second conductive type (n-type) organic semiconductor layer 22a is improved, charge separation is sufficient, and further, the series resistance is increased. Can be suppressed.

  The hole blocking layer 21a is made of bathocuproine, TiOx (titanium oxide film including an amorphous structure), or the like, and preferably has a thickness of about 0.5 nm to 1000 nm. By setting the thickness within the range of about 0.5 nm to 1000 nm, the coverage of the hole blocking layer 21a can be improved, and an increase in series resistance can be suppressed.

  In the configuration of FIG. 3, the electron blocking layer 25a is made of PEDOT: PSS or the like, and the thickness is preferably about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the electron blocking layer 25a can be improved, and an increase in series resistance can be suppressed.

  The first conductivity type (p-type) organic semiconductor layer 24b is made of copper phthalocyanine or the like, and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the covering property of the first conductive type (p-type) organic semiconductor layer 24b is improved, the charge separation is sufficient, and the increase in series resistance is suppressed. be able to.

  The second conductivity type (n-type) organic semiconductor layer 22b is made of fullerene C60 or the like and preferably has a thickness of about 0.5 nm to 200 nm. By setting the thickness within the range of about 0.5 nm to 200 nm, the coverage of the second conductive type (n-type) organic semiconductor layer 22b is improved, charge separation is sufficient, and further, the series resistance is increased. Can be suppressed.

  In the configuration of FIG. 4, the electron block layer 25 b is made of PEDOT: PSS or the like and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the electron blocking layer 25b can be improved, and an increase in series resistance can be suppressed.

  The bulk hetero layer 26 is made of thiophene derivative P3HT, fullerene derivative PCBM, or the like, and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the spectral sensitivity of the bulk hetero layer 26 is increased, and the series resistance can be reduced.

  The hole blocking layer 21c is made of bathocuproine, TiOx (titanium oxide layer including an amorphous structure), or the like, and preferably has a thickness of about 0.5 nm to 1000 nm. By setting the thickness within the range of about 0.5 nm to 1000 nm, the coverage of the hole blocking layer 21c can be improved, and an increase in series resistance can be suppressed.

  In the configuration of FIG. 5, the electron block layer 25 is made of PEDOT: PSS or the like and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the electron blocking layer 25 can be improved, and an increase in series resistance can be suppressed.

  The first conductivity type (p-type) organic semiconductor layer 24d is made of copper phthalocyanine or the like, and preferably has a thickness of about 1 to 200 nm. By setting the thickness within the range of about 1 to 200 nm, the coverage of the first conductive type (p-type) organic semiconductor layer 24d is improved, charge separation is sufficient, and further, the increase in series resistance is suppressed. be able to.

The second conductivity type (n-type) organic semiconductor layer 22d is made of fullerene C60 or the like, and preferably has a thickness of about 0.5 nm to 200 nm. By setting the thickness within the range of about 0.5 nm to 200 nm, the covering property of the second conductive type (n-type) organic semiconductor layer 22d is improved, charge separation is sufficient, and the series resistance is increased. Can be suppressed.

  The hole blocking layer 21c is made of bathocuproine, TiOx (titanium oxide layer including an amorphous structure), or the like, and preferably has a thickness of about 0.5 nm to 1000 nm. By setting the thickness within the range of about 0.5 nm to 1000 nm, the coverage of the hole blocking layer 21c can be improved, and an increase in series resistance can be suppressed.

<Translucent recombination layer>
The translucent recombination layer 4 is a layer for facilitating recombination of electrons and holes between the organic photoelectric conversion layer 2 and the translucent photoelectric conversion layer 3.

  The translucent recombination layer 4 may include at least one of a metal, a conductive oxide, and a conductive polymer. In this case, recombination of electrons and holes is facilitated, and the translucent recombination layer 4 with a small light loss can be obtained.

  Moreover, the translucent recombination layer 4 is preferably composed of island-shaped portions made of a plurality of independent metals. In this case, there is an advantage that good translucency can be obtained, and an advantage that it can be used as a growth nucleus of the organic photoelectric conversion layer 2 to be laminated next. In this case, the work function difference between the translucent photoelectric conversion layer 3 and the organic photoelectric conversion layer 2 is reduced, and the translucent photoelectric conversion layer 3 and the organic photoelectric conversion layer 2 are reduced. Electron and hole transfer is facilitated.

  Moreover, it is preferable that the translucent recombination layer 4 has a shape having a plurality of through holes, such as a mesh shape or a lattice shape. In this case, there is an advantage that good translucency can be obtained and an advantage that it can be used as a growth nucleus of the organic photoelectric conversion layer 2 to be laminated next. Moreover, the work function difference between the translucent photoelectric conversion layer 3 and the organic photoelectric conversion layer 2 is reduced, and the electrons and positive electrons between the translucent photoelectric conversion layer 3 and the organic photoelectric conversion layer 2 are reduced. The movement of the hole becomes easy.

  The ease of electron transfer and hole transfer is such that the translucent recombination layer 4 has a plurality of through holes when the translucent recombination layer 4 is made of islands made of a plurality of independent metals. Higher than if you have one. That is, island-shaped parts made of fine metal particles have higher surface energy and improved catalytic properties, a higher proportion of steps, kinks, etc. on the surface, and increased active sites with increased surface area. For reasons such as

  When the translucent recombination layer 4 is composed of islands made of a plurality of metals, there is a gap between the islands, and other layers enter the gap. It can be said that the optical recombination layer 4 is layered as a whole.

  In the case where the translucent recombination layer 4 is made of a metal or an island-shaped portion made of a plurality of metals, the material is platinum group elements such as platinum and palladium, or silver, aluminum, titanium, It consists of metals such as iron, copper, indium, chromium and iridium. In this case, the translucent recombination layer 4 is formed by vacuum deposition, sputtering, thermal decomposition of a coated complex, electrodeposition, or the like.

  The conductive oxide is made of tin-doped indium oxide, fluorine-doped tin oxide, antimony-doped tin oxide, aluminum-doped zinc oxide, gallium-doped zinc oxide, zinc oxide, indium oxide, tin oxide, titanium oxide, niobium-doped titanium oxide. An oxide that can function as a transparent electrode is preferable. The translucent recombination layer 4 made of a conductive oxide is formed by sputtering, vapor deposition, chemical vapor deposition, spin coating, plating, or the like.

  The material of the conductive polymer is preferably polyethylene dioxythiophene (PEDOT) (which may be doped with polystyrene sulfonate or toluene sulfonate), polyvinyl carbazole, polythiophene, polypyrrole, or the like. Polyethylene dioxythiophene, polyophene, and polypyrrole are formed by a coating method such as a spin coating method and a cast method, and polyvinylcarbazole and polythiophene are formed by an electrodeposition method.

  Moreover, it is preferable that at least 1 layer of the translucent recombination layer 4 is a catalyst layer. Such a catalyst layer can reduce the overvoltage acting on the organic photoelectric conversion layer and the translucent photoelectric conversion layer, and thus can reduce the overvoltage necessary for charge recombination. In addition, the catalyst layer may contain at least one of platinum, palladium, nickel, aluminum, and silver from the viewpoint of enhancing the overvoltage reduction action.

  Further, the translucent recombination layer 4 may be a laminate of a plurality of layers. By laminating a plurality of layers, charge transfer between the organic photoelectric conversion layer 2 and the translucent recombination layer 4, and between the translucent recombination layer 4 and the translucent photoelectric conversion layer 3, It can be performed more smoothly.

And the translucent recombination layer 4 comprised in such a multilayer is the 1st catalyst layer which touches the organic type photoelectric converting layer 2, and the 2nd catalyst layer which touches the translucent photoelectric converting layer 3. An intermediate layer interposed between the first catalyst layer and the second catalyst layer, and the surface resistivity of the intermediate layer is 1.0 × 10 ³ Ω / □ (square) or more. It is preferable that it is 0 × 10 ¹⁰ Ω / □ (square) or less. In such a form, while realizing recombination of charges between the translucent recombination layer and the organic photoelectric conversion layer, the translucent photoelectric conversion is performed by suppressing the movement of charges in the in-plane direction of the intermediate layer. Since recombination of charges in the layer can be reduced, photoelectric conversion efficiency can be further increased. Examples of the intermediate layer include the conductive oxides described above. Further, the surface resistivity of the intermediate layer can be measured by, for example, a four probe resistivity measurement method. In addition, the catalyst layer may have a shape having an island-shaped portion made of at least one of a metal, a conductive oxide, and a conductive polymer, or may have a shape having a plurality of through holes.

<Translucent photoelectric conversion layer>
As the translucent photoelectric conversion layer 3 having a non-single crystal semiconductor layer, a hydrogenated amorphous silicon semiconductor layer having a pin junction structure continuously deposited by a plasma CVD method is preferable.

  The translucent photoelectric conversion layer 3 includes, for example, a first conductivity type (n-type) amorphous silicon semiconductor layer 32, an intrinsic type (i-type) amorphous silicon semiconductor layer 33, from the organic photoelectric conversion layer 2 side. A pin junction structure in which the second conductivity type (p-type) amorphous silicon semiconductor layers 34 are sequentially stacked is used, but a nip junction structure that is a reverse junction may be used.

  The translucent photoelectric conversion layer 3 is not limited to the above-described amorphous silicon semiconductor layer. If the i-type semiconductor layer is amorphous, at least one of the p-type semiconductor layer and the n-type semiconductor layer has microcrystals. Or a hydrogenated amorphous silicon alloy layer. For example, the p-type semiconductor layer on the light incident side is preferably a hydrogenated amorphous silicon carbide layer, in which case the light transmissivity is high and the light loss is further reduced.

  The translucent photoelectric conversion layer 3 can be formed by a catalytic CVD method or the like. Further, when the plasma CVD method and the catalytic CVD method are combined, photodegradation can be suppressed and reliability can be improved. The first conductive type amorphous silicon semiconductor layer 32, the intrinsic type amorphous silicon semiconductor layer 33, and the second conductive type amorphous silicon semiconductor layer 34 can be continuously deposited under the respective film forming conditions by the CVD method. It can be formed in a short time at a low cost, which is preferable.

For example, a p-type a-Si: H layer (“a-Si” means amorphous silicon and “: H” means hydrogen dope), which is the second conductivity type amorphous silicon semiconductor layer 34. SiH ₄ gas, H ₂ gas, B ₂ H ₆ gas (diluted to 500 ppm with H ₂ gas) as source gas
The gas is formed by optimizing the flow rates of these gases. The thickness of the p-type a-Si: H layer is preferably 50 to 200 mm, more preferably 80 to 120 mm. By setting it within the range of 50 to 200 cm, an internal electric field can be easily formed in the translucent photoelectric conversion layer 3, and a light amount loss in the p-type a-Si: H layer can be reduced.

  The i-type a-Si: H layer which is the intrinsic type amorphous silicon semiconductor layer 33 is formed by using SiH4 gas and H2 gas as source gases and optimizing the flow rates of these gases. The thickness of the i-type a-Si: H layer is preferably 500 to 5000 mm, more preferably 1500 to 2500 mm (0.15 μm to 0.25 μm). By setting the thickness within the range of 500 to 5000 mm, a sufficient photocurrent can be obtained and the light transmittance can be enhanced.

The n-type a-Si: H layer, which is the first conductive type amorphous silicon semiconductor layer 32, uses SiH ₄ gas, H ₂ gas, and PH ₃ gas (those diluted to 1000 ppm with H ₂ gas) as source gases. The flow rates of these gases are optimized and formed. The thickness of the n-type a-Si: H layer is preferably 50 to 200 mm, more preferably 80 to 120 mm. By setting it within the range of 50 to 200 mm, an internal electric field can be easily formed in the translucent photoelectric conversion layer 3, and the light amount loss in the n-type a-Si: H layer can be reduced.

  The temperature at the time of forming the first conductive type amorphous silicon semiconductor layer 32, the intrinsic type amorphous silicon semiconductor layer 33, and the second conductive type amorphous silicon semiconductor layer 34 is 150 ° C. to 300 ° C. in any case. More preferably, 180 ° C to 240 ° C is preferable. By setting the temperature within the range of 150 ° C. to 300 ° C., an optical semiconductor having good characteristics can be easily obtained.

  In this embodiment, since the light-transmitting photoelectric conversion layer and the organic photoelectric conversion layer are laminated, the short-wavelength light (wavelength of about 300 to 600 nm) is generated by the thin-film light-transmitting photoelectric conversion layer. It is well photoelectrically converted, long wavelength light (wavelength of about 600 to 900 nm) is well photoelectrically converted in the organic photoelectric conversion layer, and high conversion efficiency is obtained by combining the conversion efficiencies of both photoelectric conversion layers. In addition, when light is incident from the translucent substrate side, long wavelength light transmitted through the thin film type translucent photoelectric conversion layer can be photoelectrically converted by the organic photoelectric conversion layer, and light in a wide wavelength range can be efficiently converted. Good photoelectric conversion.

  In this embodiment, a translucent photoelectric conversion layer that absorbs short-wavelength light and transmits almost all long-wavelength light is disposed on the light incident side, and an organic photoelectric conversion layer is disposed on the rear side. Therefore, the organic photoelectric conversion layer on the rear side does not directly receive strong light such as sunlight. As a result, the organic photoelectric conversion layer does not directly receive strong light such as sunlight, and the light-transmitting photoelectric conversion layer drastically reduces short-wavelength light including ultraviolet rays. It is reduced and high reliability can be obtained.

  In addition, since the organic photoelectric conversion layer and the translucent photoelectric conversion layer can be formed by a low-temperature process with a substrate temperature of about 500 ° C. or less, a stacked structure that provides high conversion efficiency can be obtained at a conventional temperature of about 1400 ° C. It can be manufactured more easily and easily than a photoelectric conversion device that requires a high-temperature process at a lower cost.

  Examples of the stacked photoelectric conversion device of this embodiment will be described below. A stacked photoelectric conversion device 1 having the configuration shown in FIG. 1 was produced as follows.

<Formation process of translucent photoelectric conversion layer 3>
As the conductive substrate 31, a glass substrate (size 1 cm × 2) on which a light-transmitting conductive layer 31b made of a SnO ₂ : F layer (F-doped SnO ₂ layer) having a surface resistivity of 10Ω / □ (square) is formed.
cm and a thickness of about 0.11 cm), and a thin film type translucent photoelectric conversion layer 3 was formed on one main surface thereof. The translucent photoelectric conversion layer 3 was formed as follows.

  Using a plasma CVD apparatus, a p-type a-Si: H layer (H-doped amorphous silicon (a-Si) layer) as the second conductive amorphous silicon semiconductor layer 34 on the light-transmitting conductive layer 31b, An i-type a-Si: H layer as the intrinsic type amorphous silicon semiconductor layer 33 and an n-type a-Si: H layer as the first conductive type amorphous silicon semiconductor layer 32 are successively formed in a vacuum. did.

The p-type a-Si: H layer uses SiH ₄ gas, H ₂ gas, and B ₂ H ₆ gas (diluted to 500 ppm with H ₂ gas) as source gases, and the flow rates of these gases are 3 sccm and 10 sccm, respectively. The thickness was 2 sccm and the thickness was 90 mm (9 nm).

The i-type a-Si: H layer was formed using SiH ₄ gas and H ₂ gas as source gases, the flow rates of these gases being 30 sccm and 80 sccm, respectively, and the thickness being 2000 mm (200 nm).

The n-type a-Si: H layer uses SiH ₄ gas, H ₂ gas, and PH ₃ gas (diluted to 1000 ppm with H ₂ gas) as source gases, and the flow rates of these gases are 3 sccm, 30 sccm, and 6 sccm, respectively. And a thickness of 100 mm (10 nm).

  The temperature of the glass substrate during the formation of the p-type a-Si: H layer, i-type a-Si: H layer, and n-type a-Si: H layer was 220 ° C. in all cases.

<Formation process of translucent recombination layer 4>
Next, a Pt layer as the translucent recombination layer 4 was formed on the translucent photoelectric conversion layer 3 with a thickness of 5 nm by a sputtering method. At this time, the Pt layer had a thickness of about 1 nm and was very thin, so it was formed in an island shape.

<Formation process of organic photoelectric conversion layer 2>
Next, the organic photoelectric conversion layer 2 was formed on the translucent recombination layer 4. The organic photoelectric conversion layer 2 was formed as follows.

Using a vacuum deposition apparatus, on the translucent recombination layer 4, a first conductive type (p-type) organic semiconductor layer 24 made of copper phthalocyanine, a dye layer 23 made of tin (II) phthalocyanine, and a first fullerene made of fullerene. A two-conductivity (n-type) organic semiconductor layer 22 and a hole blocking layer 21 made of bathocuproine were successively formed in a vacuum.

  The first conductive type (p-type) organic semiconductor layer 24 made of copper phthalocyanine was heated to 540 ° C. in a quartz crucible in a vacuum vapor deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The dye layer 23 made of tin phthalocyanine was heated to 520 ° C. in a quartz crucible in a vacuum deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The second conductive type (n-type) organic semiconductor layer 22 made of fullerene was heated to 580 ° C. in a quartz crucible in a vacuum deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The bathocuproine hole blocking layer 21 was heated to 180 ° C. in a pBN crucible in a vacuum deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

<Formation process of electrode 5>
Next, the electrode 5 was formed on the organic photoelectric conversion layer 2. The electrode 5 was formed as follows using a vacuum evaporation apparatus.

  The electrode 5 made of silver was formed into a mask in vacuum. The electrode 5 was deposited by heating silver particles on a tantalum boat in a vacuum deposition apparatus. The deposition rate was 0.02 nm per second at the start of deposition, and 0.1 nm per second after forming a thickness of 40 nm.

Thereby, the stacked photoelectric conversion device 1 was produced. About the obtained stacked photoelectric conversion device 1 having an area of 0.5 cm 2, photoelectric conversion characteristics were evaluated in nitrogen gas. A xenon arc lamp was used as the light source, and the current and the distance from the light source were adjusted so that the amount of light was equivalent to 100 mW / cm 2 under AM 1.5 using a standard cell for evaluating the light intensity.

  The characteristic of only the translucent photoelectric conversion layer 3 was an open end voltage of 0.83 V, and the characteristic of only the organic photoelectric conversion layer 2 was an open end voltage of 0.27 V. In the stacked photoelectric conversion device 1 in which the translucent recombination layer 4 is provided between them, an open-end voltage of 1.08 V was obtained, and almost no leakage current was observed.

  A stacked photoelectric conversion device 1 having the configuration of FIG. 2 was produced as follows.

<Formation process of translucent photoelectric conversion layer 3>
As the translucent substrate 31, a glass substrate (size 1 cm × 2) on which a translucent conductive layer 31b made of a SnO ₂ : F layer (F-doped SnO ₂ layer) having a surface resistivity of 10Ω / □ (square) is formed.
cm and a thickness of about 0.11 cm), and a thin film type translucent photoelectric conversion layer 3 was formed on one main surface thereof. The translucent photoelectric conversion layer 3 was formed as follows.

  Using a plasma CVD apparatus, a p-type a-Si: H layer (H-doped amorphous silicon (a-Si) layer) as the second conductive amorphous silicon semiconductor layer 34 on the light-transmitting conductive layer 31b, An i-type a-Si: H layer as the intrinsic type amorphous silicon semiconductor layer 33 and an n-type a-Si: H layer as the first conductive type amorphous silicon semiconductor layer 32 are successively formed in a vacuum. did.

The p-type a-Si: H layer uses SiH ₄ gas, H ₂ gas, and B ₂ H ₆ gas (diluted to 500 ppm with H ₂ gas) as source gases, and the flow rates of these gases are 3 sccm and 10 sccm, respectively. The thickness was 2 sccm and the thickness was 90 mm (9 nm).

The i-type a-Si: H layer was formed using SiH ₄ gas and H ₂ gas as source gases, the flow rates of these gases being 30 sccm and 80 sccm, respectively, and the thickness being 2000 mm (200 nm).

The n-type a-Si: H layer uses SiH ₄ gas, H ₂ gas, and PH ₃ gas (diluted to 1000 ppm with H ₂ gas) as source gases, and the flow rates of these gases are 3 sccm, 30 sccm, and 6 sccm, respectively. And a thickness of 100 mm (10 nm).

  The temperature of the glass substrate during the formation of the p-type a-Si: H layer, i-type a-Si: H layer, and n-type a-Si: H layer was 220 ° C. in all cases.

<Formation process of translucent recombination layer 4>
Next, a Pt layer as the translucent recombination layer 4 was formed on the translucent photoelectric conversion layer 3 with a thickness of 5 nm by a sputtering method. At this time, the Pt layer had a thickness of about 1 nm and was very thin, so it was formed in an island shape.

<Formation process of organic photoelectric conversion layer 2>
Next, the organic photoelectric conversion layer 2 was formed on the translucent recombination layer 4. The organic photoelectric conversion layer 2 was formed as follows.

  First, as the electron blocking layer 25, an electron blocking layer 25 made of polystyrene dioxythiophene (PEDOT: PSS) doped with polystyrene sulfonate dispersed in an aqueous solvent was spin-coated on the translucent recombination layer 4. Dried in air at 110 ° C. to form.

  Using a vacuum deposition apparatus, a first conductive type (p-type) organic semiconductor 24a made of copper phthalocyanine, a dye layer 23a made of tin (II) phthalocyanine, and a second conductive type made of fullerene (on the electron block layer 25). An n-type) organic semiconductor layer 22a and a hole blocking layer 21a made of bathocuproine were successively formed in a vacuum.

  The first conductive type (p-type) organic semiconductor 24a made of copper phthalocyanine was heated to 540 ° C. in a quartz crucible in a vacuum vapor deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The dye layer 23a made of tin phthalocyanine was heated to 520 ° C. in a quartz crucible in a vacuum deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The second conductive type (n-type) organic semiconductor layer 22a made of fullerene was heated to 580 ° C. in a quartz crucible in a vacuum vapor deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

  The hole blocking layer 21a made of bathocuproine was heated to 180 ° C. in a pBN crucible in a vacuum deposition apparatus and deposited at a deposition rate of about 0.1 nm per second.

<Formation process of electrode 5>
Next, the electrode 5 was formed on the organic photoelectric conversion layer 2. The electrode 5 was formed as follows using a vacuum evaporation apparatus.

  The electrode 5 made of silver was formed into a mask in vacuum. The electrode 5 was deposited by heating silver particles on a tantalum boat in a vacuum deposition apparatus. The deposition rate was 0.02 nm per second at the start of deposition, and 0.1 nm per second after forming a thickness of 40 nm. Thereby, the stacked photoelectric conversion device 1 was produced.

About the obtained stacked photoelectric conversion device 1 having an area of 0.5 cm ² , photoelectric conversion characteristics were evaluated in nitrogen gas. A xenon arc lamp was used as the light source, and the current and distance from the light source were adjusted so that the amount of light was equivalent to 100 mW / cm ² under AM 1.5 using a standard cell for evaluating the light intensity.

  The characteristic of only the translucent photoelectric conversion layer 3 was an open end voltage of 0.83 V, and the characteristic of only the organic photoelectric conversion layer 2 was an open end voltage of 0.27 V. In the stacked photoelectric conversion device 1 in which the translucent recombination layer 4 is provided between them, an open circuit voltage of 0.99 V was obtained. Although the open-circuit voltage was lower than that in Example 1, the short circuit current density was about 1.3 times that of the stacked photoelectric conversion device 1 in Example 1 due to the provision of the electron blocking layer 25.

It is sectional drawing which shows an example of the laminated photoelectric conversion apparatus of this Embodiment. It is sectional drawing which shows the other example of the laminated photoelectric conversion apparatus of this Embodiment. It is sectional drawing which shows the other example of the laminated photoelectric conversion apparatus of this Embodiment. It is sectional drawing which shows the other example of the laminated photoelectric conversion apparatus of this Embodiment. It is sectional drawing which shows the other example of the laminated photoelectric conversion apparatus of this Embodiment. It is sectional drawing which shows an example of the photoelectric conversion module of this Embodiment. It is sectional drawing which shows the other example of the photoelectric conversion module of this Embodiment. It is sectional drawing which shows the other example of the photoelectric conversion module of this Embodiment.

Explanation of symbols

1: Stacked photoelectric conversion device 2: Organic photoelectric conversion layer 3: Translucent photoelectric conversion layer 4: Translucent recombination layer 5: Electrode 6: Sealing material 7: Counter substrate 21: Hole blocking layer 22: Second conductivity type (n-type) organic semiconductor layer 23: Dye layer 24: First conductivity type (p-type) organic semiconductor layer 25: Electron block layer 26: Bulk heterolayer 31: Conductive substrate 31a: Translucent substrate 31b: Translucent conductive layer 32: first conductive type (n-type) amorphous silicon semiconductor layer 33: intrinsic (i-type) amorphous silicon semiconductor layer 34: second conductive type (p-type) amorphous Silicon semiconductor layer

Claims (11)

A translucent photoelectric conversion layer having a non-single-crystal semiconductor layer;
A translucent recombination layer formed on the translucent photoelectric conversion layer for recombining electrons and holes;
A stacked photoelectric conversion device comprising: an organic photoelectric conversion layer including an organic semiconductor formed on the translucent recombination layer.   2. The stacked photoelectric conversion device according to claim 1, wherein a peak wavelength of spectral sensitivity of the organic photoelectric conversion layer is on a longer wavelength side than a peak wavelength of spectral sensitivity of the translucent photoelectric conversion layer.   3. The stacked photoelectric conversion device according to claim 1, wherein the organic photoelectric conversion layer has spectral sensitivity with respect to light transmitted through the translucent photoelectric conversion layer.   4. The stacked photoelectric conversion device according to claim 1, wherein the translucent photoelectric conversion layer has a pin structure including an i-type amorphous silicon layer. 5.   5. The stacked photoelectric conversion device according to claim 1, wherein the translucent recombination layer includes at least one of a metal, a conductive oxide, and a conductive polymer.   6. The stacked photoelectric conversion device according to claim 1, wherein the translucent recombination layer includes island-shaped portions made of a plurality of independent metals.   The stacked photoelectric conversion device according to claim 1, wherein the translucent recombination layer has a plurality of through holes.   The stacked photoelectric conversion device according to claim 1, wherein the translucent recombination layer includes a catalyst layer. The translucent recombination layer includes a first catalyst layer in contact with the organic photoelectric conversion layer and a second catalyst layer in contact with the translucent photoelectric conversion layer, and the first An intermediate layer interposed between the catalyst layer and the second catalyst layer;
9. The stacked photoelectric conversion device according to claim 8, wherein the intermediate layer has a surface resistivity of 1.0 × 10 ³ Ω / □ or more and 1.0 × 10 ¹⁰ Ω / □ or less.   10. The stacked photoelectric conversion device according to claim 8, wherein the catalyst layer contains at least one of platinum, palladium, nickel, aluminum, and silver.   A photoelectric conversion module in which a plurality of stacked photoelectric conversion devices according to claim 1 are arranged in the horizontal direction and are electrically connected to each other.

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