JP6234680B2 - Semiconductor device, solar cell, light emitting element, and method for manufacturing light receiving element - Google Patents

Description

  The present invention relates to a semiconductor device, a solar cell, a light emitting element, and a method for manufacturing a light receiving element.

  In recent years, semiconductor devices using the quantum size effect have attracted attention. The quantum size effect means that when the average particle size of the particles is reduced to about nanometers, the electrons that make up the particles are confined in a minute region, and the degree of freedom of movement of the electrons is extremely controlled, thereby removing the electrons. This is a phenomenon where the energy gained is quantized. Particles in which electrons are confined in such a minute region are called quantum dots, and the light absorption wavelength and photoelectric conversion characteristics are controlled by adjusting the band gap with the average particle diameter. For example, by making the photoelectric conversion layer of the solar cell into a quantum dot structure, it becomes possible to absorb light of a wide range of wavelengths that could not be used conventionally, and exciton generation before losing high energy light as thermal energy Therefore, a solar cell having high conversion efficiency can be obtained.

  As described above, for a solar cell employing a quantum dot structure in the photoelectric conversion layer (hereinafter referred to as a quantum dot solar cell), for example, Non-Patent Document 1 discloses a quantum dot solar cell that can absorb light of a wide range of wavelengths. It has been reported that a theoretical efficiency as high as 74.6% can be achieved in one intermediate band solar cell.

Non-Patent Document 2 includes a photoelectric conversion layer including titanium oxide (TiO ₂ ) and lead sulfide (PbS) quantum dots (hereinafter referred to as PbS particles) between the transparent conductive layer and the counter conductive layer. Colloidal quantum dots (CQD) solar cells have been disclosed. In this photoelectric conversion layer, the PbS particles absorb light such as sunlight and are responsible for charge transport as a P-type semiconductor, and TiO ₂ is responsible only for charge transport. Here, a P-type semiconductor is a semiconductor in which positive holes are used as carriers that carry charges, and an N-type semiconductor is that in which negative charges are used as carriers that carry charges. Means semiconductor. Further, currents are generated in the P-type and N-type semiconductors by moving holes and electrons as carriers. Then, in the photoelectric conversion layer, the connecting portion between PbS particles and TiO ₂ has become a PN junction, charge separation is promoted in the PN junction.

  Further, Non-Patent Document 3 discloses a CQD solar cell including a photoelectric conversion layer having a quantum dot structure including PbS particles, as in the solar cell of Non-Patent Document 2. In the CQD solar cell of Non-Patent Document 3, an organic / inorganic hybrid surface stabilization treatment using a halide is introduced when the photoelectric conversion layer is formed. Thereby, since recombination of carriers in the photoelectric conversion layer is suppressed, the current generated in the photoelectric conversion layer is easily extracted to the outside, and the conversion efficiency is about 7%, which exceeds the conversion efficiency of the conventional CQD solar cell. Has been obtained.

  As described above, active research and development has been progressing for semiconductor devices having a quantum dot structure photoelectric conversion layer such as a quantum dot solar cell for further performance improvement.

Appl. Phys. Lett, 2011, 98, 171108 ACSano, 2010, 4, 3374 Nature Nanotechnol, 2012, 10.1038 / NNANO. 2012.12.27, 1

However, in the production of a conventional quantum dot solar cell, a high-temperature process or a high-vacuum process is required for forming the photoelectric conversion layer (see Non-Patent Document 1). Further, even in the case of a CQD solar cell that is said to be easily manufacturable, a high-temperature process such as firing at 500 ° C. is required in forming a TiO ₂ layer that becomes an N-type semiconductor layer, and the firing of the TiO ₂ layer Later, it was necessary to allow the PbS particles to be a P-type semiconductor layer to be dissolved in a solvent and to form a film by spin coating, and then to stand overnight to dry the solvent (see Non-Patent Documents 2 and 3). Thus, in the conventional method for manufacturing a semiconductor device having a photoelectric conversion layer having a quantum dot structure, a high vacuum process or a high temperature process is required in forming the photoelectric conversion layer, and each process is complicated. there were.

  The present invention has been made in view of the above circumstances, and a semiconductor device capable of forming a photoelectric conversion layer having a quantum dot structure in which charge separation at a PN junction is favorably generated in a simpler process, and the semiconductor device. It is an object of the present invention to provide a method for manufacturing the solar cell, the light emitting element, and the light receiving element used.

The method for manufacturing a semiconductor device of the present invention includes a photoelectric conversion layer having a quantum dot structure having a PN junction composed of an interface between a P-type semiconductor particle and an N-type semiconductor particle, and the P-type semiconductor particle and the N-type semiconductor particle A semiconductor device manufacturing method in which at least one of the semiconductor particles is a quantum dot in a state in which the moving direction of electrons is restricted in all three dimensions by an average particle diameter, on a substrate, A photoelectric conversion layer is formed by aerosol deposition method in which a semiconductor layer made of one of the P type semiconductor particles and the N type semiconductor particles is dispersed in a semiconductor layer made of one of the conductive type semiconductor particles. In this case, the P-type semiconductor particles and the N-type semiconductor particles are simultaneously sprayed on the substrate to form the photoelectric conversion layer, and the P-type semiconductor particles and the N-type semiconductor particles are formed. The weight ratio of the conductive semiconductor particles forming the semiconductor layer to the conductive semiconductor particles dispersed in the semiconductor layer is 80:20 to 99.1: 0.1, depending on the carrier gas. The speed of the P-type semiconductor particles and the N-type semiconductor particles is accelerated within a range of 10 to 1000 m / s and sprayed onto the substrate.
In the manufacturing method of the semiconductor device of the present invention, the carrier gas accelerates the speed of the P-type semiconductor particles and the N-type semiconductor particles within a range of 10 to 250 m / s, and sprays it on the substrate. The photoelectric conversion layer may be formed.
In the method for producing a semiconductor device of the present invention, it is preferable that an average particle diameter of one or both of the P-type semiconductor particles and the N-type semiconductor particles is 1 nm to 10 nm .

The manufacturing method of the solar cell, light emitting element, and light receiving element of the present invention is characterized in that a solar cell, a light emitting element, or a light receiving element is obtained by the semiconductor device manufacturing method of the present invention.

  According to the method for manufacturing a semiconductor device, a solar cell, a light emitting element, and a light receiving element of the present invention, it is possible to form a photoelectric conversion layer having a quantum dot structure in which charge separation at a PN junction is favorably performed by a simpler process.

It is sectional drawing which shows the semiconductor device which is 1st embodiment of this invention. It is sectional drawing which shows the solar cell using the semiconductor device which is 1st embodiment of this invention. It is sectional drawing which shows the light emitting element using the semiconductor device which is 1st embodiment of this invention. It is sectional drawing which shows the light receiving element using the semiconductor device which is 1st embodiment of this invention. It is a schematic diagram which shows the manufacturing apparatus for manufacturing the semiconductor device of this invention. It is a schematic diagram which shows the other manufacturing apparatus for manufacturing the semiconductor device of this invention. It is sectional drawing for demonstrating the manufacturing process of the semiconductor device which is 1st embodiment of this invention. It is sectional drawing which shows the semiconductor device which is 2nd embodiment of this invention. It is sectional drawing which shows the solar cell using the semiconductor device which is 2nd embodiment of this invention. It is sectional drawing which shows the light emitting element using the semiconductor device which is 2nd embodiment of this invention. It is sectional drawing which shows the light receiving element using the semiconductor device which is 2nd embodiment of this invention. It is sectional drawing for demonstrating the manufacturing process of the semiconductor device which is 2nd embodiment of this invention.

  Hereinafter, a semiconductor device according to an embodiment of the present invention and a method for manufacturing a solar cell, a light emitting element, and a light receiving element using the semiconductor device will be described with reference to the drawings. The drawings used in the following description are schematic, and the length, width, thickness ratio, and the like are not necessarily the same as actual ones, and can be changed as appropriate.

(First embodiment)
FIG. 1 is a sectional view showing a semiconductor device 10 according to the first embodiment of the present invention.
As shown in FIG. 1, the semiconductor device 10 includes a substrate 21, a transparent conductive layer 22 formed on one surface of the substrate 21, a photoelectric conversion layer 25 formed on the transparent conductive layer 22, The counter conductive layer 27 formed on the photoelectric conversion layer 25 and the current extraction part 29 formed on the transparent conductive layer 22 are provided. The photoelectric conversion layer 25 of this embodiment is a composite layer in which an N-type semiconductor layer 23 (first conductivity type semiconductor layer) and a P-type semiconductor layer 24 (second conductivity type semiconductor layer) are sequentially stacked. is there.

  If the board | substrate 21 is a member used as the base of the transparent conductive layer 22, and is comprised with the material applicable to manufacture and utilization of a quantum dot solar cell, a kind etc. will not be specifically limited. Examples of such a substrate include resin films such as PET (polyethylene terephthalate) or PEN (polyethylene naphthalate), soda lime glass, borosilicate glass, quartz glass, borosilicate glass, Vycor glass, and alkali-free glass. And a glass substrate made of blue plate glass and white plate glass.

  The transparent conductive layer 22 is provided to constitute the first electrode of the semiconductor device 10, and is formed on the substrate 21 by a sputtering method or a printing method. Examples of the transparent conductive layer 22 include tin oxide (ITO), fluorine-doped tin oxide (FTO), zinc oxide (ZnO), tin oxide (SnO), antimony-doped tin oxide (ATO), indium oxide / zinc oxide (IZO). ), Gallium oxide / zinc oxide (GZO), or the like is used.

  The photoelectric conversion layer 25 includes an N-type semiconductor layer 23 and a P-type semiconductor layer 24 formed on the N-type semiconductor layer 23.

The N-type semiconductor layer 23 is composed of N-type semiconductor particles 23p (first-conductivity-type semiconductor particles) (not shown) such as metal oxide having a function of carrying charges by using negatively charged electrons as carriers. Examples of such metal oxides include titanium oxide (TiO ₂ ) and zinc oxide (ZnO). The average particle size of the N-type semiconductor particles 23p is preferably 1 nm to 2000 nm. Thereby, an interface between the N-type semiconductor and the P-type semiconductor is appropriately formed, and the conversion efficiency of the photoelectric conversion layer 25 is improved.

  The N-type semiconductor particles 23p may be quantum dots that are in a state in which the moving direction of electrons is limited in all three-dimensional directions by the average particle diameter, or may not be quantum dots. When the N-type semiconductor particles 23p are quantum dots, the average particle size of the N-type semiconductor particles 23p is 1 nm to from the point of increasing the quantum size effect of the N-type semiconductor particles 23p and improving the conversion efficiency of the photoelectric conversion layer 25. 10 nm is preferred.

Among the metal oxides, TiO ₂ used in the industry is roughly classified into anatase type and rutile type, and brookite type and amorphous TiO ₂ are also known. From the viewpoint of improving electron conductivity and productivity, the anatase TiO ₂ is suitable as the N-type semiconductor particle 23p. Incidentally, N-type semiconductor particles 23p may be a mixture of anatase type TiO ₂ and rutile TiO _2, may be only rutile TiO _2. In this case, it is preferable that 50 wt% to 0 wt% of anatase TiO ₂ is appropriately mixed with 50 wt% to 100 wt% of rutile TiO ₂ .

  In the semiconductor device 10 of the present embodiment, the N-type semiconductor layer 23 is formed by spraying N-type semiconductor particles 23p on the transparent conductive layer 22 by a powder spraying method. In the powder spraying method, the film-forming raw material is made into particles (hereinafter referred to as raw material particles) and sprayed onto the film-forming target with a carrier gas, using auxiliary energy such as collision energy, heat, electricity, etc. In this method, the raw material particles are formed on the object to be formed without the need for post-treatment. As such a powder spraying method, for example, an aerosol deposition method (hereinafter referred to as AD method), a spray method, a cold spray method, an electrostatic spray method, a thermal spraying method and the like are known.

  The AD method is a method in which raw material particles are accelerated to a subsonic speed to a supersonic speed by a carrier gas such as helium and sprayed onto a substrate. At least part of the raw material particles that collide with the surface of the base material bite into the surface of the base material and are not easily peeled off. In addition, a new surface is formed on the surface of the base material and the surface of the raw material particle by the collision of the raw material particles with the surface of the base material, and the base material and the raw material particles are mainly joined on this new surface. By continuing the spraying of the raw material particles, another raw material particle collides with the raw material particles that have digged into the substrate surface. Due to the collision between the raw material particles, a new surface is formed on the surface of the respective raw material particles, and the raw material particles are joined mainly on the new surface. In the collision between the raw material particles, a temperature rise that melts the raw material particles hardly occurs. Therefore, a grain boundary layer made of vitreous does not substantially exist at the interface where the raw material particles are joined to each other. By continuing the spraying of the raw material particles, a layer or a film formed by joining a large number of raw material particles to the surface of the base material is gradually formed. The formed layer or film has sufficient strength due to the joining of the raw material particles, and therefore does not require baking by baking. As described above, in the AD method, a favorable porous layer can be formed by adjusting the conditions at the time of spraying the raw material particles. Therefore, the N-type semiconductor layer 23 is formed using the AD method. Is preferred.

The N-type semiconductor layer 23 may be formed by spin-coating a solution in which N-type semiconductor particles 23p such as TiO ₂ are dispersed in a solvent such as toluene on the transparent conductive layer 22.

  The P-type semiconductor layer 24 absorbs sunlight and the like, and P-type semiconductor particles 24p (second-conductivity-type semiconductor) such as an inorganic semiconductor having a function of carrying charges by using positively charged holes as carriers. Particle). An example of such an inorganic semiconductor is PbS. The average particle size of the P-type semiconductor particles 24p is preferably 1 nm to 2000 nm. Thereby, an interface between the N-type semiconductor and the P-type semiconductor is appropriately formed, and the conversion efficiency of the photoelectric conversion layer 25 is improved.

  The P-type semiconductor particles 24p may be quantum dots or may not be quantum dots. However, when the N-type semiconductor particles 23p are not quantum dots, it is preferable to use the P-type semiconductor particles 24p as quantum dots. When the P-type semiconductor particles 24p are quantum dots, the average particle size of the P-type semiconductor particles 24p is 1 nm to from the point that the quantum size effect of the P-type semiconductor particles 24p is increased to improve the conversion efficiency of the photoelectric conversion layer 25. 10 nm is preferred.

  In the semiconductor device 10 of the present embodiment, the P-type semiconductor layer 24 is formed by applying the P-type semiconductor particles 24p to the N-type semiconductor layer by a powder spraying method such as an AD method, a spray method, a cold spray method, an electrostatic spray method, or a spraying method. 23 is formed by spraying. Accordingly, the photoelectric conversion layer 25 is formed continuously by a room temperature process and in a relatively short time without the need for post-processing. In addition, when the P-type semiconductor particles 24p are sprayed onto the N-type semiconductor layer 23, a part of the P-type semiconductor particles 24p are connected individually or plurally to the N-type semiconductor layer 23 on the P-type semiconductor layer 24 side. It penetrates in contact with the interface with the mold semiconductor layer 24 (see FIG. 1). The interface between the N-type semiconductor layer 23 and the P-type semiconductor particles 24p and the P-type semiconductor layer 24 is a PN junction 26. Electrons flow to the N-type semiconductor and holes to the P-type semiconductor. By flowing, charge separation is promoted.

  The P-type semiconductor layer 24 may be formed by spin-coating a solution in which P-type semiconductor particles 24p such as PbS are dispersed in a solvent such as toluene on the N-type semiconductor layer 23. However, when the N-type semiconductor layer 23 is formed by the spin coating, the P-type semiconductor layer 24 is formed by the above-described powder spraying method.

  The thickness of at least one of the N-type semiconductor layer 23 and the P-type semiconductor layer 24 constituting the photoelectric conversion layer 25 is preferably 0.05 μm to 20 μm. Thereby, light absorption in the photoelectric conversion layer 25 is moderately performed, and electrons and holes are efficiently transferred to the respective electrodes of the transparent conductive layer 22 and the counter conductive layer 27 in the N-type semiconductor layer 23 and the P-type semiconductor layer 24, respectively. Transported.

The counter conductive layer 27 is provided to form the second electrode of the semiconductor device 10 and is formed on the P-type semiconductor layer 24 by a sputtering method or a printing method. The counter conductive layer 27 is opposed to the transparent conductive layer 22 via the photoelectric conversion layer 25 in the thickness direction of the semiconductor device 10. For example, molybdenum oxide (MoO _x , where x is an integer), gold, silver, or the like is used for the counter conductive layer 27.

  The current extraction portion 29 is provided to extract the current in the transparent conductive layer 22 and is formed on the transparent conductive layer 22 where the photoelectric conversion layer 25 is not formed in a plan view by a sputtering method or a printing method. ing. For the current extraction part 29, for example, gold, copper or the like is used.

In the present invention, the first conductive type semiconductor particles are, for example, N type semiconductor particles, and the second conductive type semiconductor particles are P in the case where the first conductive type semiconductor particles are N type. Type semiconductor particles. When the first conductivity type semiconductor particles are P type semiconductor particles, the second conductivity type semiconductor particles are N type semiconductor particles.
The case of semiconductor particles has been described above as an example, but the same applies to the case of a semiconductor layer.
That is, the photoelectric conversion layer 25 of the semiconductor device 10 described above may be a composite layer in which a P-type semiconductor layer and an N-type semiconductor layer are sequentially stacked. In this case, since the opposing conductive layer 27 is in contact with the N-type semiconductor layer, it is preferable to use a material having a work function suitable for the N-type semiconductor for the opposing conductive layer 27, for example, calcium or aluminum.

  FIG. 2 is a cross-sectional view showing a solar cell 100 using the semiconductor device 10 according to the first embodiment of the present invention. As shown in FIG. 2, the solar cell 100 is a quantum dot solar cell, and is manufactured by connecting the wiring 111 to the opposing conductive layer 27 of the semiconductor device 10 and connecting the wiring 112 to the current extraction portion 29. Can do. In the solar cell 100, when the photoelectric conversion layer 25 is irradiated with light such as sunlight, electrons in the N-type semiconductor layer 23 move to the transparent conductive layer 22 side, and holes in the P-type semiconductor layer 24 face each other. By moving to the conductive layer 27 side, charge separation at the PN junction 26 is promoted, and a photocurrent is generated. Photocurrent is taken out of the solar cell 100 from the terminals 111 e and 112 e of the wirings 111 and 112.

  FIG. 3 is a cross-sectional view showing a light emitting element 101 using the semiconductor device 10 according to the first embodiment of the present invention. As shown in FIG. 3, the light emitting element 101 is a so-called light emitting diode, and a wiring 115 is connected to the counter conductive layer 27 and the current extraction unit 29 so that a forward bias is applied to the PN junction 26 of the photoelectric conversion layer 25. Can be manufactured. In the light emitting element 101, a negative voltage is applied to the N-type semiconductor layer 23 from the power source of the wiring 115 through the current extraction part 29 and the transparent conductive layer 22, and to the P-type semiconductor layer 24 through the counter conductive layer 27. A positive voltage is applied, and electrons in the N-type semiconductor layer 23 and holes in the P-type semiconductor layer 24 are attracted to the PN junction 26 side. In the PN junction 26, the energy possessed by electrons and holes is released as light. Therefore, by controlling the voltage application amount to the N-type and P-type semiconductor layers 23 and 24, the light emission intensity and the like are adjusted, and the light emitting element 101 operates.

  FIG. 4 is a sectional view showing a light receiving element 102 using the semiconductor device 10 according to the first embodiment of the present invention. As shown in FIG. 4, the light receiving element 102 is a so-called photodiode, and a wiring 116 is connected to the counter conductive layer 27 and the current extraction unit 29 so that a reverse bias is applied to the PN junction 26 of the photoelectric conversion layer 25. Can be manufactured. 4 illustrates a circuit configuration in which the wiring 116 is connected to the wirings 111 and 112 similar to the solar cell 100 in FIG. 2, but the wiring 116 is not limited to this configuration, and the wiring 116 is negatively connected to the P-type semiconductor layer 24. It is only necessary to have a configuration to which a voltage can be applied. When light is applied to the photoelectric conversion layer 25 in a state where a negative voltage is applied to the P-type semiconductor layer 24 from the power source of the wiring 116 through the counter conductive layer 27, photoelectrons are generated by the internal photoelectric effect at the PN junction 26. The generated photoelectrons move to the N-type semiconductor layer 23 and the holes move to the P-type semiconductor layer 23 to generate an electromotive force. Accordingly, a direct current can be taken out from the light receiving element 102 from the terminals 111 e and 112 e of the wirings 111 and 112.

  As mentioned above, the semiconductor device applicable to the quantum dot solar cell has been exemplified and described as the semiconductor device 10 in the present embodiment, but the semiconductor device 10 includes the photoelectric conversion layer 25 having the quantum dot structure having the PN junction 26. If it is, it will not be specifically limited.

  Next, a method for manufacturing the semiconductor device 10 of the present embodiment (hereinafter simply referred to as a manufacturing method) will be described.

  In the manufacturing method of the present embodiment, for example, a film forming apparatus 50 shown in FIG. 5 is used. The film forming apparatus 50 includes a film forming chamber 51 for accommodating the substrate D and forming the photoelectric conversion layer 25 and the like on one surface Da thereof by a powder spraying method such as the AD method. In the film forming chamber 51, a stage 52 having an arrangement surface 52a for arranging the substrate D is provided. The stage 52 is movable in the horizontal direction with the base material D disposed. A vacuum pump 53 is connected to the film forming chamber 51, and the inside of the film forming chamber 51 is set to a negative pressure.

  In the film forming chamber 51, a nozzle 54 is disposed so that the opening 54a faces the one surface Da of the substrate D disposed on the arrangement surface 52a of the stage 52. The opening 54a is preferably rectangular in plan view if the base material D is rectangular in plan view from the viewpoint of uniformly forming a film on one surface Da of the base material D. Is not particularly limited. The nozzle 54 is connected to the gas cylinder 56 through the transport pipe 55. A mass flow controller 57, an aerosol generator 58, a crusher 59, and a classifier 60 are provided in the middle of the transport pipe 55 from the gas cylinder 56 side.

  In the film forming apparatus 50, a carrier gas such as helium is supplied from the gas cylinder 56 to the carrier pipe 55, and the flow rate of the carrier gas is adjusted by the mass flow controller 57. The aerosol generator 58 is loaded with raw material particles for spraying, and the raw material particles are dispersed in a carrier gas flowing in the carrier pipe 55 and conveyed to the crusher 59 and the classifier 60. Then, the raw material particles 71 are injected from the nozzle 54 onto the one surface Da of the substrate D at a subsonic to supersonic injection speed.

  In the manufacturing method of this embodiment, the film forming apparatus 70 shown in FIG. 6 can also be used. In the constituent elements of the film forming apparatus 70, the same constituent elements as those of the film forming apparatus 50 shown in FIG.

  The film forming apparatus 70 is provided with two transfer pipes 55A and 55B as transfer paths for injecting the raw material particles and the transfer gas toward the substrate D. That is, in the film forming apparatus 70, two different kinds of raw material particles 71A and 71B can be sprayed continuously or simultaneously on the surface Da of the substrate D from the nozzles 54A and 54B of the transport pipes 55A and 55B. The functions of the gas cylinders 56A and 56B, the mass flow controllers 57A and 57B, the aerosol generators 58A and 58B, the crushers 59A and 59B, and the classifiers 60A and 60B provided in the two transport pipes 55A and 55B are respectively formed into films. The apparatus 50 has the same functions as those of the gas cylinder 56, the mass flow controller 57, the aerosol generator 58, the crusher 59, and the classifier 60 of the apparatus 50.

  The film forming apparatus 70 enables continuous or simultaneous spraying of two different kinds of raw material particles. However, the nozzles 54A and 54B are brought close to each other, and the arrangement of the two conveying pipes 55A and 55B and the constituent elements provided on them is provided. If there is a storage space similar to that of the film forming apparatus 50 that transports a mixture of a single type of raw material particles or a plurality of types of raw material particles through a single transport pipe 55 and sprays it from the nozzle 54 Good. Therefore, according to the film forming apparatus 70, space saving of the semiconductor device manufacturing apparatus can be achieved.

Then, each process of the manufacturing method of this embodiment is demonstrated.
First, as shown in FIG. 7B, a transparent conductive layer 22 made of ITO, FTO or the like is formed on a substrate 21 such as a glass substrate shown in FIG. 7A using a method such as sputtering. The transparent conductive layer 22 may be formed by spraying the raw material particles of the transparent conductive layer 22 on the substrate 21 by a powder spraying method using the film forming apparatus 50 or the film forming apparatus 70.

  Next, the transparent conductive layer 22 shown in FIG. 7B was formed on the arrangement surface 52a of the stage 52 in the film forming chamber 51 of the film forming apparatus 50 shown in FIG. 5 or the film forming apparatus 70 shown in FIG. The substrate 21 is arranged as the base material D. One surface Da of the base material D is the exposed surface of the transparent conductive layer 22 (the surface opposite to the surface in contact with the substrate 21 of the transparent conductive layer 22). Thereafter, the inside of the film forming chamber 51 is evacuated by the vacuum pump 53. Further, helium is supplied as a carrier gas from the gas cylinder 56 into the film forming chamber 51 via the transfer pipe 55, and the inside of the film forming chamber 51 is made a helium atmosphere.

  In the present embodiment, the speed of the raw material particles accelerated by the carrier gas (helium) is preferably 10 m / s to 1000 m / s, and more preferably 10 m / s to 250 m / s. By being below the upper limit of the above range, when colliding with the base material or already deposited raw material particles, the raw material particles are not excessively crushed, and the film is formed while maintaining the particle size at the time of spraying substantially. The By being at least the lower limit of the above range, the raw material particles of the transparent conductive layer 22 can be reliably bonded to the base material or the raw material particles already deposited, and a sufficiently strong layer or film can be formed. In addition, what is necessary is just to adjust suitably the speed | rate of the raw material particle accelerated by carrier gas according to the kind of base material.

  In the manufacturing method of this embodiment, it is preferable that the raw material particles are sprayed in a room temperature environment. Here, normal temperature refers to a temperature sufficiently lower than the melting point of the raw material particles of the transparent conductive layer 22, and is substantially 200 ° C. or lower. The temperature of the normal temperature environment is preferably not higher than the melting point of the substrate D.

Next, while the helium is continuously supplied from the gas cylinder 56 into the film forming chamber 51, as shown in FIG. 7C, powder such as AD method is formed on the transparent conductive layer 22 formed on the substrate 21. An N-type semiconductor layer 23 made of a metal oxide such as TiO ₂ , ZnO, SnO ₂ is formed using a spraying method. The thickness of the N-type semiconductor layer 23 is preferably 0.05 μm to 20 μm from the viewpoint of efficiently transporting electrons and holes in the N-type semiconductor layer 23 and the P-type semiconductor layer 24, respectively.

  In order to form the N-type semiconductor layer 23 on the transparent conductive layer 22, the aerosol generator 58 of the film forming apparatus 50 is loaded with the N-type semiconductor particles 23 p made of the metal oxide fine particles, and the N-type semiconductor is formed. The particles are dispersed in a carrier gas flowing in the carrier pipe 55 and conveyed to the crusher 59 and the classifier 60. Then, N-type semiconductor particles 23 p are sprayed as raw material particles 71 from the opening 54 a of the nozzle 54 onto the surface of the transparent conductive layer 22. In addition, the average particle diameter of the metal oxide constituting the N-type semiconductor particles 23p is a particle diameter obtained by a method of measuring and averaging a plurality of particle diameters by SEM observation or a laser diffraction particle size distribution measuring device ( It can be measured by a method of determining the peak value of the (volume average diameter) distribution.

In the production method of the present embodiment, a case of using anatase type TiO ₂ particles as an N-type semiconductor particles 23p example. The formed the surface of the transparent conductive layer 22 on the substrate 21, by blowing anatase TiO ₂ particles at high speed, with bonding the transparent conductive layer 22 and the anatase type TiO ₂ particles, anatase-type TiO ₂ grains To form an N-type semiconductor layer 23 made of anatase-type TiO ₂ particles on the transparent conductive layer 22. As the N-type semiconductor particles 23p, a mixture of anatase TiO ₂ and rutile TiO ₂ or only rutile TiO ₂ may be used. In this case, it is preferable that 50 wt% to 0 wt% of anatase TiO ₂ is appropriately mixed with 50 wt% to 100 wt% of rutile TiO ₂ .

When the N-type semiconductor particles 23p are sprayed, the speed of the N-type semiconductor particles 23p accelerated by the carrier gas is preferably 10 to 1000 m / s, more preferably 10 to 250 m / s. When the speed of the N-type semiconductor particles 23p is equal to or less than the above upper limit, the N-type semiconductor particles 23p are maintained in a particle size at the time of spraying the N-type semiconductor particles 23p without being excessively crushed when colliding with the transparent conductive layer 22. And can be laminated. In addition, since the speed of the N-type semiconductor particles 23p is equal to or higher than the lower limit, the N-type semiconductor particles 23p are surely bonded to the substrate 21 or the already deposited N-type semiconductor particles 23p, so The semiconductor layer 23 can be formed. The speed of the N-type semiconductor particles 23p such as anatase-type TiO ₂ particles accelerated by the carrier gas may be appropriately adjusted in accordance with the material of the transparent conductive layer 22 and the N-type semiconductor layer 23 within the above range.

In the present embodiment, the N-type semiconductor particles 23p are preferably sprayed in a normal temperature environment. Here, normal temperature refers to a temperature sufficiently lower than the melting point of the N-type semiconductor particles 23p such as anatase-type TiO ₂ particles, and is substantially 200 ° C. or lower. Moreover, it is preferable that the temperature of a normal temperature environment is below the melting point of the base material D.

  In the manufacturing method of the present embodiment, when the AD method is selected as the powder spraying method to form the porous N-type semiconductor layer 23, the porosity of the N-type semiconductor layer 23 is that of the N-type semiconductor particles 23p. Although influenced by the spraying speed and the spraying angle, the factor that mainly affects the average particle diameter of the N-type semiconductor particles 23p to be sprayed. Within a preferable average particle diameter of 1 nm to 2000 nm, the porosity of the N-type semiconductor layer 23 increases as the average particle diameter increases, and the porosity of the N-type semiconductor layer 23 decreases as the average particle diameter decreases. Tend to be lower. Note that if the porosity of the N-type semiconductor layer 23 is too high, the charge transport path in the N-type semiconductor layer 23 is shredded and the charge goes around, resulting in a longer charge transport path and photoelectric conversion. The conversion efficiency of the layer 25 is undesirably lowered. Further, if the porosity of the N-type semiconductor layer 23 is too low, the N-type semiconductor layer 23 becomes too dense and the interface between the N-type semiconductor and the P-type semiconductor is reduced, which is not preferable. Therefore, it is preferable to appropriately adjust the average particle size of the N-type semiconductor particles 23p within the above range.

  The N-type semiconductor particles 23p may or may not be quantum dots. In the case where the N-type semiconductor particles 23p are quantum dots, the average particle size of the N-type semiconductor particles 23p is set to 1 nm to 1 nm in terms of enhancing the quantum size effect of the N-type semiconductor particles 23p and improving the conversion efficiency of the photoelectric conversion layer 25. The thickness is preferably 10 nm.

Known AD methods include, for example, the ultrafine particle beam deposition method and apparatus disclosed in International Publication No. WO01 / 27348A1, or the brittle material ultrafine particle low temperature molding method and apparatus disclosed in Japanese Patent No. 3265481. It is done. In these known AD methods, it is considered important to preliminarily add internal strains to the extent that cracks are generated or not by pre-processing the raw material particles to be sprayed with a ball mill or the like. By adding this internal strain, the sprayed raw material particles can be easily crushed and deformed when colliding with the base material or the already deposited raw material particles, thereby forming a dense film. It is described that it can be done. Also in the manufacturing method of this embodiment, a moderately dense N-type semiconductor layer 23 can be formed by applying internal strain to the N-type semiconductor particles 23p such as anatase TiO ₂ particles.

  Next, as shown in FIG. 7D, the carrier gas such as helium is continuously supplied from the gas cylinder 56 into the film forming chamber 51 without opening the film forming chamber 51 of the film forming apparatus 50. A P-type semiconductor layer 24 made of an inorganic semiconductor such as PbS is formed on the N-type semiconductor layer 23 by using a powder spraying method such as a method. In this step, if necessary, the film forming chamber 51 may be opened to form the P-type semiconductor layer 24. However, the P-type semiconductor layer 24 may be continuously formed on the N-type semiconductor layer 23 without opening the film forming chamber 51. By forming the type semiconductor layer 24, it is possible to reliably prevent impurities from being mixed into the photoelectric conversion layer 25. The thickness of the P-type semiconductor layer 24 is preferably 0.05 μm to 20 μm from the viewpoint of efficiently transporting electrons and holes in the N-type semiconductor layer 23 and the P-type semiconductor layer 24, respectively.

  Specifically, after the P-type semiconductor particles 24p made of inorganic semiconductor fine particles for spraying are loaded into the aerosol generator 58, the P-type semiconductor particles 24p are dispersed in the carrier gas flowing in the carrier pipe 55, and then crushed. To the container 59 and the classifier 60. Then, P-type semiconductor particles 24p are sprayed from the opening 54a of the nozzle 54 onto the surface of the N-type semiconductor layer 23 (the surface opposite to the surface in contact with the transparent conductive layer 22 of the N-type semiconductor layer 23). Similar to the N-type semiconductor layer 23, in order to enhance the quantum size effect of the P-type semiconductor particles 24p in the P-type semiconductor layer 24, the P-type semiconductor particles 24p include inorganic semiconductor fine particles having an average particle diameter of 1 nm to 2000 nm. Is preferably used. The average particle size of the inorganic semiconductor constituting the P-type semiconductor particles 24p can be measured by a method similar to the method for measuring the average particle size of the metal oxide constituting the N-type semiconductor particles 23p of the N-type semiconductor layer 23. .

  The P-type semiconductor particles 24p may or may not be quantum dots. However, when the N-type semiconductor particles 23p are not quantum dots, the P-type semiconductor particles 24p are quantum dots. When the P-type semiconductor particles 24p are quantum dots, the average particle size of the P-type semiconductor particles 24p is set to 1 nm to 1 nm in that the quantum size effect of the P-type semiconductor particles 24p is enhanced to improve the conversion efficiency of the photoelectric conversion layer 25. The thickness is preferably 10 nm.

  The preferable spraying conditions and the like in the formation of the P-type semiconductor layer 24 using the powder spraying method are the same as those described above for the N-type semiconductor layer 23, and thus the description thereof is omitted. In this step, when the P-type semiconductor particles 24p are sprayed on the N-type semiconductor layer 23, the P-type semiconductor is formed on the surface of the N-type semiconductor layer 23 on the P-type semiconductor layer 24 side as shown in FIG. Part of the particles 24p enters. Accordingly, a part of the P-type semiconductor particles 24p that have entered the N-type semiconductor layer 23 and a PN junction 26 in the photoelectric conversion layer 25 of the semiconductor device 10 are formed at the interface between the N-type semiconductor layer 23 and the P-type semiconductor layer 24. Is done.

When forming the N-type semiconductor layer 23 and the P-type semiconductor layer 24, when the film forming apparatus 70 shown in FIG. 6 is used, the N-type semiconductor particles 23p for spraying on the aerosol generators 58A and 58B in advance and the P-type semiconductor are used. Each of the particles 24p is loaded, and the N-type semiconductor particles 23p and the P-type semiconductor particles 24p are dispersed in the carrier gas flowing in the carrier pipes 55A and 55B, and the crushers 59A and 59B and the classifiers 60A and 60B are dispersed. To each. Then, setting the forming step and blowing conditions of the N-type semiconductor layer 23 and the P-type semiconductor layer 24 described above and in the same manner, the N-type semiconductor particles 23p from the opening 54a _A nozzle 54A spraying and, the nozzle 54B sequentially performing blowing of P-type semiconductor particles 24p from the opening 54a _B.

  Through the process described above, the photoelectric conversion layer 25 in which the N-type semiconductor layer 23 and the P-type semiconductor layer 24 are stacked on the transparent conductive layer 22 can be formed. For either one of the N-type semiconductor layer 23 and the P-type semiconductor layer 24, the N-type semiconductor particles 23p or the P-type semiconductor particles 24p constituting the semiconductor layer are dispersed in a solvent such as toluene. The solution may be formed by spin coating with the solution. The semiconductor layer is preferably formed by spin coating at room temperature.

  Next, an opposing conductive layer 27 made of platinum, polyaniline, PEDOT, carbon, or the like is formed on the P-type semiconductor layer 24 by sputtering or printing.

  Next, a current extraction portion 29 made of gold, copper, or the like is formed on the transparent conductive layer 22 on which the photoelectric conversion layer 25 is not formed in a plan view by a sputtering method, a printing method, or the like. The current extraction portion 29 may be formed after the transparent conductive layer 22 is formed and before the photoelectric conversion layer 25 is formed.

  In the method for manufacturing the semiconductor device 10 described above, when the photoelectric conversion layer 25 is formed, a P-type semiconductor layer and an N-type semiconductor layer may be sequentially stacked on the transparent conductive layer 22. Further, as the material of the counter conductive layer 27 in contact with the N-type semiconductor layer, a material having a work function suitable for the N-type semiconductor is preferably used, and for example, calcium or aluminum can be used.

  As described above, according to the semiconductor device 10 and the manufacturing method thereof of the present embodiment, when forming at least one of the N-type semiconductor layer 23 and the P-type semiconductor layer 24 constituting the photoelectric conversion layer 25. Further, at least one of the N-type semiconductor particles 23p or the P-type semiconductor particles 24p is a quantum dot, and the N-type semiconductor particles 23p constituting the one semiconductor layer using a powder spraying method such as an AD method or the like By spraying the P-type semiconductor particles 24p, it is possible to form the photoelectric conversion layer 25 having a quantum dot structure in which charge separation at the PN junction 26 is favorably performed by a simple process without requiring a high-temperature process. In addition, by spraying the N-type semiconductor particles 23p or the P-type semiconductor particles 24p using the powder spraying method, without introducing impurities between the N-type semiconductor layer 23 and the P-type semiconductor layer 24, continuous and The N-type semiconductor layer 23 and the P-type semiconductor layer 24 can be easily stacked to form a photoelectric conversion by increasing the quantum size effect of at least one of the N-type and P-type semiconductor particles 23p and 24p. The layer 25 can have light absorption characteristics peculiar to the quantum size effect. Furthermore, since the photoelectric conversion layer 25 is formed by a room temperature process, the photoelectric conversion layer 25 and the transparent conductive layer 22 can be formed on the substrate 21 having low heat resistance. That is, the selection range of materials applicable to the manufacture of the semiconductor device 10 including the photoelectric conversion layer 25 having the quantum dot structure and the range of application of the semiconductor device 10 can be expanded.

  Moreover, according to the semiconductor device 10 and the manufacturing method thereof of the present embodiment, the photoelectric conversion layer 25 having the light absorption characteristic due to the quantum size effect of either one of the N-type semiconductor particles 23p or the P-type semiconductor particles 24p. It is possible to provide a solar cell 100, a light emitting element 101, and a light receiving element 102 that can be provided by a room temperature process.

(Second embodiment)
FIG. 8 is a sectional view showing a semiconductor device 12 according to the second embodiment of the present invention. In the constituent elements of the semiconductor device 12 of this embodiment shown in FIG. 8, the same constituent elements as those of the semiconductor device 10 of the first embodiment shown in FIG. Is omitted.

  As shown in FIG. 8, in the photoelectric conversion layer 25 of the semiconductor device 12, P-type semiconductor particles 24p are scattered in the N-type semiconductor layer 23 made of N-type semiconductor particles 23p (not shown). Therefore, the interface between the N-type semiconductor layer 23 and the P-type semiconductor particles 24 p becomes the PN junction 26, and charge separation occurs well at the PN junction 26. The components of the semiconductor device 12 other than the photoelectric conversion layer 25 are the same as the components of the semiconductor device 10 of the first embodiment.

  The photoelectric conversion layer 25 of the semiconductor device 12 described above may be a layer in which N-type semiconductor particles 23p are scattered in a P-type semiconductor layer 24 made of P-type semiconductor particles 24p. In this case, the N-type semiconductor particles 23p and the N-type semiconductor layer 23 shown in FIG. 8 are replaced with P-type semiconductor particles and a P-type semiconductor layer, respectively, and the P-type semiconductor particles 24p are replaced with N-type semiconductor particles.

  9 to 11 are cross-sectional views respectively showing a solar cell 120, a light emitting element 121, and a light receiving element 122 using the semiconductor device 12 according to the second embodiment of the present invention. In addition, in the constituent elements of the solar cell 120, the light emitting element 121, and the light receiving element 122 shown in FIGS. 9 to 11, the solar cell 100, the light emitting element 101, and the semiconductor device 10 of the first embodiment shown in FIGS. The same components as those of the light receiving element 102 are denoted by the same reference numerals.

  Solar cell 120, light emitting element 121, and light receiving element 122 are obtained by replacing semiconductor device 10 in solar cell 100, light emitting element 101, and light receiving element 102 with semiconductor device 12, respectively. Therefore, each manufacturing method of the solar cell 120, the light emitting element 121, and the light receiving element 122 is the same as the manufacturing method of the solar cell 100, the light emitting element 101, and the light receiving element 102 except that the semiconductor device 10 is replaced with the semiconductor device 12. Explanation is omitted.

Then, the manufacturing method of the semiconductor device 12 of this embodiment is demonstrated.
The manufacturing method of the semiconductor device 12 is similar to the manufacturing method of the semiconductor device 10 of the first embodiment. The forming process of the transparent conductive layer 22, the forming process of the photoelectric conversion layer 25 using the powder spraying method, Forming a layer 27 and a current extraction portion 29. Hereinafter, in the description of the manufacturing method of the semiconductor device 12, the description of the same content as the manufacturing method of the semiconductor device 10 is omitted.

  First, the same processes as those described in FIGS. 7A and 7B in the method for manufacturing the semiconductor device 10 of the first embodiment are performed, and as shown in FIGS. 12A and 12B, A transparent conductive layer 22 made of ITO or the like is formed on the substrate 21.

Subsequently, as shown in FIG. 12C, a metal oxide such as TiO ₂ , ZnO, or SnO ₂ is formed on the transparent conductive layer 22 formed on the substrate 21 using a powder spraying method such as the AD method. A photoelectric conversion layer 25 is formed by dispersing P-type semiconductor particles 24p made of an inorganic semiconductor such as PbS in an N-type semiconductor layer 23 made of a material. The thickness of the photoelectric conversion layer 25 is preferably 0.05 μm to 20 μm from the viewpoint of efficiently transporting electrons and holes in the N-type semiconductor layer 23 and the P-type semiconductor layer 24, respectively.

  When the photoelectric conversion layer 25 of the semiconductor device 12 is formed, when the film forming apparatus 50 shown in FIG. 5 is used, the N-type semiconductor particles 23p and the P-type semiconductor particles 24p for spraying are previously mixed in the aerosol generator 58. The mixture is loaded, and the mixture is dispersed in the carrier gas flowing in the carrier pipe 55 and conveyed to the crusher 59 and the classifier 60, respectively. Then, the said mixture is sprayed from the opening part 54a of the nozzle 54 similarly to the formation process of the photoelectric converting layer 25 in the manufacturing method of the semiconductor device 10 of 1st embodiment, and the setting of spraying conditions. The mixing ratio of the N-type semiconductor particles 23p and the P-type semiconductor particles 24p is preferably N-type semiconductor particles 23p: P-type semiconductor particles 24p = 80: 20 to 99.1: 0.1 (weight ratio). N-type semiconductor particles 23p: P-type semiconductor particles 24p = 99: 1. By setting the mixing ratio, the P-type semiconductor particles 24p are moderately dispersed in the N-type semiconductor layer 23.

When forming the N-type semiconductor layer 23 and the P-type semiconductor layer 24, when the film forming apparatus 70 shown in FIG. 6 is used, the N-type semiconductor particles 23p for spraying on the aerosol generators 58A and 58B in advance and the P-type semiconductor are used. Each of the particles 24p is loaded, and the N-type semiconductor particles 23p and the P-type semiconductor particles 24p are dispersed in the carrier gas flowing in the carrier pipes 55A and 55B, and the crushers 59A and 59B and the classifiers 60A and 60B are dispersed. To each. Thereafter, spraying and N-type semiconductor particles 23p from the opening 54a _A nozzle 54A, the P-type semiconductor particles 24p from the opening 54a _B of the nozzle 54B sprayed simultaneously. At this time, in order to uniformly disperse the P-type semiconductor particles 24p in the N-type semiconductor layer 23, the spraying conditions of the N-type semiconductor particles 23p and the P-type semiconductor particles 24p are set respectively for the semiconductor device of the first embodiment. It is preferable to set it as 10-1000 m / s for the same reason as the manufacturing method of 10, and it is more preferable to set it as 10-250 m / s.

  As described above, by using the film forming apparatus 50 or the film forming apparatus 70, the mixing ratio of the N-type semiconductor particles 23p and the P-type semiconductor particles 24p and the spraying conditions are appropriately set. The photoelectric conversion layer 25 can be formed by dispersing the P-type semiconductor particles 24p.

Next, after performing the process similar to the formation process of the opposing conductive layer 27 and the electric current extraction part 29 in the manufacturing method of the semiconductor device 10 of 1st embodiment, after forming the opposing conductive layer 27 on the photoelectric converting layer 25, A current extraction portion 29 is formed on the transparent conductive layer 22 where the photoelectric conversion layer 25 is not formed in plan view.
Through the above steps, the semiconductor device 12 shown in FIG. 5 is completed.
In the method for manufacturing the semiconductor device 12 described above, the photoelectric conversion layer 25 may be formed by dispersing the N-type semiconductor particles 23 p in the P-type semiconductor layer 24.

  As described above, in the semiconductor device 12 and the manufacturing method thereof according to this embodiment, at least one of the N-type semiconductor particles 23p or the P-type semiconductor particles 24p is a quantum dot, and the N-type and P-type semiconductor particles 23p. , 24p are sprayed onto the transparent conductive layer 22 to form the photoelectric conversion layer 25, so that the same effect as the semiconductor device 10 of the first embodiment can be obtained. Moreover, according to the semiconductor device 12 and the manufacturing method thereof of the present embodiment, the photoelectric conversion layer 25 in which the other semiconductor particle is dispersed in one semiconductor particle of the N-type semiconductor particle 23p and the P-type semiconductor particle 24p. Is formed. By adjusting the spray speed and spray amount of each of the N-type and P-type semiconductor particles 23p, 24p, the dispersity and uniformity of the other semiconductor particle in the one semiconductor particle can be easily controlled. . Thereby, the quantum size effect in the other semiconductor particle can be further enhanced.

The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments, and various modifications are possible within the scope of the gist of the present invention described in the claims. Deformation / change is possible.
For example, a photoelectric conversion layer formed by alternately stacking N-type semiconductor layers 23 and P-type semiconductor layers 24 so that a plurality of stacked structures of N-type semiconductor layers 23 and P-type semiconductor layers 24 are stacked in the thickness direction of the semiconductor device. 25 may be formed.

  Next, the present invention will be described in detail by the following examples, but the present invention is not limited only to these examples.

Example 1
As a substrate of a semiconductor device, an FTO-glass substrate in which FTO was formed on a glass substrate in advance was used.
Next, anatase TiO ₂ particles having an average particle diameter of about 20 nm were used as raw material particles for the N-type semiconductor layer.
Also, by preparing a solution in which PbS having an average particle diameter of about 5 nm is dispersed in toluene (hereinafter referred to as a PbS solution), and drying this solution under reduced pressure, PbS particles that become P-type semiconductor particles of quantum dots are obtained. Obtained.

Next, using a film forming apparatus 50 shown in FIG. 5, TiO ₂ particles were formed on an FTO-glass substrate at room temperature (about 20 ° C.).
Specifically, in the film forming chamber 51, TiO ₂ particles were sprayed onto the FTO-glass substrate from a nozzle 54 having a rectangular opening 54a of 10 mm × 0.5 mm in plan view. At this time, nitrogen (N ₂ ) was used as the carrier gas, and this nitrogen was supplied from the gas cylinder 56 to the carrier pipe 55, and the flow rate was adjusted by the mass flow controller 57. TiO ₂ particles for spraying are loaded into the aerosol generator 58, dispersed in nitrogen, transported to the crusher 59 and the classifier 60, and sprayed from the nozzle 54 onto the FTO-glass substrate to form a TiO ₂ layer. did. Thereafter, the inside of the film forming chamber 51 was set to a negative pressure (100 Pa) by a vacuum pump 53 connected to the film forming chamber 51. The conveyance speed of nitrogen accompanying the mixture in the nozzle 54 was 5 mm / sec.
Next, a PbS layer is formed by depositing PbS particles on the TiO ₂ layer at room temperature using the film forming apparatus 50, and a semiconductor device before forming the opposite conductive layer (simply referred to as a semiconductor device) is formed. Manufactured. PbS particles were formed by the same spraying method as the formation of the TiO ₂ layer.

(Example 2)
A semiconductor device was manufactured in the same procedure as in Example 1 except that the P-type semiconductor layer of the photoelectric conversion layer in the semiconductor device was formed by spin coating a PbS solution.

(Comparative example)
The same FTO-glass substrate as in Example 1 was screen-printed with a printing paste containing the same TiO ₂ particles as in Example 1, and then baked at 500 ° C. for 30 minutes, so that the TiO of the photoelectric conversion layer of the semiconductor device _Two layers were produced. Moreover, the PbS layer of the photoelectric conversion layer of a semiconductor device was formed by spin-coating the same PbS solution as Example 1 on an N type semiconductor layer. Other steps were performed in the same manner as in Example 1 to manufacture a semiconductor device.

SEM photographs of the semiconductor devices manufactured in Examples 1 and 2 and the comparative example were taken using an electron microscope, and cross-sectional observation of each semiconductor device was performed.
As a result, in the semiconductor device of Example 1, the TiO ₂ layer was 0.1 μm and the PbS layer was 0.5 μm, and these layers were in good contact. Further, it was confirmed that the same TiO ₂ layer and PbS layer were formed in Example 2 and Comparative Example.
From the above results, according to the manufacturing method of the present invention, it was confirmed that a photoelectric conversion layer having a quantum dot structure having a PN junction can be formed by a room temperature process and a simple process.

  DESCRIPTION OF SYMBOLS 10,12 ... Semiconductor device, 21 ... Substrate, 23 ... N type semiconductor layer (first conductive type semiconductor layer), 23p ... N type semiconductor particle (first conductive type semiconductor particle), 24 ... P type semiconductor layer ( Second conductivity type semiconductor layer), 24p ... P type semiconductor particles (second conductivity type semiconductor particles), 25 ... Photoelectric conversion layer, 26 ... PN junction

Claims (6)

A photoelectric conversion layer having a quantum dot structure having a PN junction composed of an interface between a P-type semiconductor particle and an N-type semiconductor particle, and having at least one conductivity type of the P-type semiconductor particle and the N-type semiconductor particle A semiconductor device manufacturing method in which the semiconductor particles are quantum dots in a state in which the moving direction of electrons is restricted in all three dimensions by an average particle size,
A photoelectric conversion layer in which the other conductive type semiconductor particles are dispersed in a semiconductor layer made of one of the P type semiconductor particles and the N type semiconductor particles on the substrate is disposed on the substrate. When forming by the position method,
By simultaneously blowing the P-type semiconductor particles and the N-type semiconductor particles to the substrate, the photoelectric conversion layer is formed,
Of the P-type semiconductor particles and the N-type semiconductor particles, the weight ratio of the conductive semiconductor particles forming the semiconductor layer to the conductive semiconductor particles dispersed in the semiconductor layer is 80:20 to 99.99. 1: 0.1, the velocity of the P-type semiconductor particles and the N-type semiconductor particles is accelerated within a range of 10 to 1000 m / s by a carrier gas and sprayed onto the substrate. Manufacturing method.   The photoelectric conversion layer is formed by accelerating the velocity of the P-type semiconductor particles and the N-type semiconductor particles within a range of 10 to 250 m / s with the carrier gas and spraying on the substrate. A method for manufacturing a semiconductor device according to claim 1.   3. The method of manufacturing a semiconductor device according to claim 1, wherein an average particle diameter of one or both of the P-type semiconductor particles and the N-type semiconductor particles is 1 nm to 10 nm. Method of manufacturing a solar cell characterized by obtaining a solar cell by the method of manufacturing a semiconductor device according to any one of claims 1-3. Method of fabricating a light emitting device, characterized in that to obtain a light emitting device by the method of manufacturing a semiconductor device according to any one of claims 1-3. The manufacturing method of the light-receiving element, characterized in that to obtain a light receiving element by the method of manufacturing a semiconductor device according to any one of claims 1-3.

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