WO2016203724A1

WO2016203724A1 - Solid state imaging element and method for manufacturing solid state imaging element, photoelectric conversion element, imaging device, and electronic device

Info

Publication number: WO2016203724A1
Application number: PCT/JP2016/002668
Authority: WO
Inventors: Yoshiaki Obana; Nobuyuki Matsuzawa; Shuzi Hayase; Shyam Sudhir Pandey; Yuhei Ogomi
Original assignee: Sony Semiconductor Solutions Corporation
Priority date: 2015-06-15
Filing date: 2016-06-02
Publication date: 2016-12-22
Also published as: JP6754156B2; JP2017005196A

Abstract

Proper photoelectric conversion is achieved with great spectroscopic characteristics for light of a specific wavelength and a high photoelectric conversion efficiency. A photoelectric conversion layer that achieves photoelectric conversion of incident light, a hole transport layer that transports a hole to the photoelectric conversion layer, and an electron transport layer that transports an electron to the photoelectric conversion layer are stacked between a pair of electrodes, and the photoelectric conversion layer is configured to have a layered organic perovskite material that selectively absorbs light only in a specific wavelength region. The present technology can be applied to a solid state imaging element.

Description

SOLID STATE IMAGING ELEMENT AND METHOD FOR MANUFACTURING SOLID STATE IMAGING ELEMENT, PHOTOELECTRIC CONVERSION ELEMENT, IMAGING DEVICE, AND ELECTRONIC DEVICE

The present technology relates to a solid state imaging element and a method for manufacturing a solid state imaging element, a photoelectric conversion element, an imaging device, and an electronic device, and more particularly, to a solid state imaging element and a method for manufacturing a solid state imaging element, a photoelectric conversion element, an imaging device, and an electronic device, which are adapted to be able to achieve photoelectric conversion of light of a specific wavelength.

<CROSS REFERENCE TO RELATED APPLICATIONS>
This application claims the benefit of Japanese Priority Patent Application JP 2015-120303 filed on June 15, 2015, the entire contents of which are incorporated herein by reference.

Vertically spectroscopic imagers having high color reproducibility, which are referred to as vertically spectroscopic solid state imaging elements have been really expected. In order to achieve the vertically spectroscopic imagers, there is a need for not only great photoelectric conversion characteristics, but also high spectroscopic selectivity.

As the vertically spectroscopic solid state imaging elements, elements using silicon (Si) materials are known.

However, the vertically spectroscopic solid state imaging elements using silicon materials, because of their small light absorption coefficients, have no choice but to increase the film thicknesses, and as a result, with the minimized pixel areas, spectroscopic characteristics have been limited by cross leakage and the like.

Therefore, in recent years, vertically spectroscopic solid state imaging elements have been proposed which have a multilayer structure of stacked photoelectric conversion films formed from organic materials.

For example, a solid state imaging element is disclosed which has sequentially stacked organic photoelectric conversion films that respectively absorb blue light, green light, and red light (see Patent Literature 1). In the solid state imaging element disclosed in Patent Literature 1, signals for the respective colors are extracted by the photoelectric conversion of light corresponding to each color in the respective organic photoelectric conversion films.

In addition, a solid state imaging element is disclosed where an organic photoelectric conversion film that absorbs green light and a silicon photodiode are stacked sequentially (see Patent Literature 2). In the solid state imaging element disclosed in Patent Literature 2, signals for green light are extracted by the organic photoelectric conversion film, and signals for blue light and red light, which are separated with the use of the difference in light approach depth, are extracted by the silicon photodiode.

Furthermore, a photoelectric conversion element for a solar cell, which uses a 3D organic perovskite material as a hybrid material of organic material-inorganic material, is known as a photoelectric conversion element which shows a high photoelectric conversion efficiency (see Non Patent Literature 1).

JP 2003-234460 A JP 2005-303266 A

Scientific reports 2: 591(2012) Published 21 August 2012

However, the organic photoelectric conversion films in

Patent Literature

1 and 2 mentioned above all fail to achieve photoelectric conversion of light adequately subjected to spectroscopic selection for each color.

In addition, the 3D organic perovskite material for use in the technique in Non Patent Literature 1 absorbs the entire region of visible light, moreover, the long-wavelength absorption is gradual, with low steepness for the wavelengths, and the spectroscopic selection is thus difficult. Therefore, the material has not been able to achieve photoelectric conversion of light effectively subjected to spectroscopic selection.

In addition, for these reasons, a method of attaching color filters is also conceivable, but becomes expensive in cost. In addition, because there is a need for use as a vertically spectroscopic element, the use of color filters makes it difficult to achieve sensitivity for necessary spectroscopic characteristics, and color filters are thus intrinsically unable to be used.

The present technology has been made in view of these circumstances, and there is a need for making photoelectric conversion possible, in particular, with high selectivity for light of a specific wavelength and a high photoelectric conversion efficiency.

A solid state imaging element of one aspect of the present technology includes: a photoelectric conversion layer that achieves photoelectric conversion of incident light; a hole transport layer that transports a hole to the photoelectric conversion layer; an electron transport layer that transports an electron to the photoelectric conversion layer; and a pair of electrodes, wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

The layered organic perovskite material may be represented by (RNH3)n-Metal-X(2+n), the R may represent at least one or more of aromatic or heterocyclic compounds having a primary amine, the Metal may represent a metal containing at least one or more of Pb, Sn, and Mn, the X may represent a halogen containing at least one or more of F, Cl, Br, and I, and the n may be a natural number.

The structure of R may control a maximum peak at absorption wavelengths and a distribution profile of the absorption wavelengths, for light in a specific wavelength region, the light selectively absorbed by the layered organic perovskite material.

The electron transport layer may include any of TiO2, NiO, WO3, and TA2O5.

The hole transport layer may include any of Spiro-OMeTAD, TiO2, ZnO, and SnO2.

The method of a solid state imaging element of one aspect of the present technology includes: a first step of forming a first electrode; a second step of forming, on top of the first electrode, an electron transport layer that transports an electron to a photoelectric conversion layer; a third step of forming, on top of the electron transport layer, the photoelectric conversion layer including a layered organic perovskite material that selectively absorbs light only in a specific wavelength region; a fourth step of forming, on top of the photoelectric conversion layer, a hole transport layer that transports a hole to the photoelectric conversion layer to achieve photoelectric conversion of incident light; and a fifth step of forming a second electrode on top of the hole transport layer.

A photoelectric conversion element of one aspect of the present technology includes: a photoelectric conversion layer that achieves photoelectric conversion of incident light; a hole transport layer that transports a hole to the photoelectric conversion layer; an electron transport layer that transports an electron to the photoelectric conversion layer; and a pair of electrodes, wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

An imaging device of one aspect of the present technology includes: a photoelectric conversion layer that achieves photoelectric conversion of incident light; a hole transport layer that transports a hole to the photoelectric conversion layer; an electron transport layer that transports an electron to the photoelectric conversion layer; and a pair of electrodes, wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

An electronic device of one aspect of the present technology includes: a photoelectric conversion layer that achieves photoelectric conversion of incident light; a hole transport layer that transports a hole to the photoelectric conversion layer; an electron transport layer that transports an electron to the photoelectric conversion layer; and a pair of electrodes, wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

A device of one aspect of the present technology includes a photoelectric conversion layer a hole transport layer and an electron transport layer and a pair of electrodes. The electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

A method of one aspect of the present technology includes: forming a first electrode; forming, on top of the first electrode, an electron transport layer that transports an electron from a photoelectric conversion layer; forming, on top of the electron transport layer, the photoelectric conversion layer including a layered organic perovskite material that selectively absorbs light only in a specific wavelength region; forming, on top of the photoelectric conversion layer, a hole transport layer that transports a hole to the photoelectric conversion layer to achieve photoelectric conversion of incident light; and forming a second electrode on top of the hole transport layer.

An electronic apparatus of one aspect of the present technology includes: a plurality of photoelectric conversion elements; a plurality of pixel regions, wherein at least one photoelectric conversion element is disposed in each pixel region, and wherein each photoelectric conversion element includes: a photoelectric conversion layer; a hole transport layer; an electron transport layer; and a pair of electrodes. An electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes and the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region. The apparatus further includes a control circuit and a logic circuit.

In one aspect of the present technology, a photoelectric conversion layer achieves the photoelectric conversion of incident light, a hole transport layer transports holes to the photoelectric conversion layer, an electron transport layer transports electrons to the photoelectric conversion layer, the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and the photoelectric conversion layer is formed from a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

An aspect of the present technology makes proper photoelectric conversion possible with great spectroscopic characteristics for light of a specific wavelength and a high photoelectric conversion efficiency.

Fig. 1 is a diagram illustrating configuration examples according to an embodiment of a solid state imaging element in accordance with the present technology applied. Fig. 2 is a diagram showing a result of observing a spin coating of a layered organic perovskite material under a SEM. Fig. 3 is a diagram for explaining spectroscopic characteristics of a photoelectric conversion element including a layered organic perovskite material. Fig. 4 is a diagram for explaining photoelectric conversion characteristics of a photoelectric conversion element including a layered organic perovskite material. Fig. 5 is a diagram for explaining voltage-current characteristics of a photoelectric conversion element including a layered organic perovskite material. Fig. 6 is a diagram illustrating a configuration example of a photoelectric conversion element including a layered organic perovskite material. Fig. 7 is a flowchart for explaining a method for manufacturing a photoelectric conversion element including a layered organic perovskite material. Fig. 8 is a schematic diagram illustrating the structure of a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied. Fig. 9 is a cross-sectional view illustrating an outline per unit pixel in a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied. Fig. 10 is a block diagram for explaining the configuration of an electronic device to which a photoelectric conversion element according to an embodiment of the present technology is applied.

<Configuration Example according to Embodiment of Solid State Imaging Element in accordance with Present Technology Applied>
Fig. 1 is a diagram illustrating configuration examples according to an embodiment of a vertically spectroscopic solid state imaging element using a photoelectric conversion film in accordance with the present technology applied.

The configuration examples of the vertically spectroscopic solid state imaging element using the photoelectric conversion film are configured to have three types of first to third solid state imaging elements 11 shown from the left in Fig. 1. Each of the three types is configured to have a structure in which photoelectric conversion elements including any of a photoelectric conversion film and a photodiode are stacked from an upper light source downward in Fig. 1.

More specifically, the first solid state imaging element 11 is provided with, as shown in the upper left part of Fig. 1, a photoelectric conversion element 21 including a photoelectric conversion film that achieves photoelectric conversion of light G (green) for the uppermost layer, and below the element, stacked

photoelectric conversion elements

31, 32 including silicon-based photodiodes for B (blue) and R (red).

In this configuration, as shown in the lower left part of Fig. 1, the photoelectric conversion of light in a wavelength band of G (green) (dashed dotted line) is achieved by the photoelectric conversion element 21, and subsequently, in the order of wavelength band from shorter to longer, the photoelectric conversion of light of B (blue) (dashed line) and R (red) (solid line) is achieved by the

photoelectric conversion elements

31, 32, thereby achieving the photoelectric conversion of the RGB (red, green, blue) in a vertically separate manner.

In addition, the second solid state imaging element 11 is provided with, as shown in the upper central part of Fig. 1,

photoelectric conversion elements

22, 21 including photoelectric conversion films that achieve the photoelectric conversion of light of B (blue) and G (green) in order from the uppermost layer, and below the elements, a stacked photoelectric conversion element 32 including a silicon-based photodiode for R (red).

In this configuration, as shown in the lower central part of Fig. 1, the photoelectric conversion of light in wavelength bands of B (blue) and G (green) is achieved by the

photoelectric conversion elements

22, 21 subsequently in the order of wavelength band from shorter to longer, and thereafter, the photoelectric conversion of light of R (red) is achieved by the photoelectric conversion element 32, thereby achieving the photoelectric conversion of the RGB (red, green, blue) in a vertically separate manner.

Furthermore, in the third solid state imaging element 11, as shown in the upper right part of Fig. 1,

photoelectric conversion elements

22, 21, 23 including photoelectric conversion films that achieve the photoelectric conversion of light of B (blue), G (green), and R (red) are stacked in order from the uppermost layer.

In this configuration, as shown in the lower central part of Fig. 1, the photoelectric conversion of light in wavelength bands of B (blue), G (green), and R (red) is achieved by the

photoelectric conversion elements

22, 21, 23 subsequently in the order of wavelength band from shorter to longer, thereby generating pixel signals of the RGB (red, green, blue) in a vertically separate manner.

In this regard, the photoelectric conversion elements 21 to 23 configured to have photoelectric conversion films are configured to have thin films of layered (2D: 2 Dimension) organic perovskite materials.

The layered organic perovskite materials are included in one material group of organic-inorganic perovskite compounds, and represented by, for example, organic-inorganic layered perovskite compounds (RNH3)2-Metal-X4. The materials have a self-organized structure structured to have organic layers (RNH3+) and inorganic semiconductor layers (PbX64-) stacked alternately. When R is a small functional group such as methyl, the materials which have a 3D structure are adapted to have broad absorption spectra.

However, when R has a large functional group of, for example, a phenyl group or a larger group, the materials are adapted to have not a 3D structure but a layered 2D structure. The materials with a 2D structure are known to have sharp spectroscopic characteristics at specific wavelengths.

The layered organic perovskite materials constituting the photoelectric conversion films for use in the photoelectric conversion elements 21 to 23 are adapted to be materials represented by the following general formula (1).

(RNH3)n-Metal-X(2n)
… General Formula (1)

In this regard, in the general formula (1), R represents at least one or more of aromatic or heterocyclic compounds having a primary amine. In addition, the Metal represents a metal containing at least one or more of Pb, Sn, and Mn. Furthermore, X represents a halogen containing at least one or more of F, Cl, Br, and I. In addition, n is a natural number.

The layered organic perovskite materials are synthesized as follows. More specifically, first, as expressed by the following reaction formula (1), phenethylamine (MA) and hydrogen iodide (HI) are reacted to synthesize a hydrogen iodide salt of the phenethylamine (MAH⁺I^-). Next, as expressed by the following reaction formula (2), the hydrogen iodide salt of the phenethylamine as an amine halide (MAH⁺I^-) and lead iodide (PbI2) are dissolved at 2 : 1 in an organic solvent of dimethylformamide to prepare an ink with a layered organic perovskite ((MAH)2PbI4) dissolved therein.

Furthermore, the ink with the layered organic perovskite dissolved therein is applied by spin coating onto cleaned glass to form a layered organic perovskite material as a photoelectric conversion layer. In this regard, as for the coating conditions, for example, the number of rotations is 2000 rpm, and the rotation time is 60 s, and under these conditions, the layered organic perovskite material prepared has a film thickness on the order of 200 nm.

The layered organic perovskite material produced in this way, when observed by, for example, a Scanning Electron Microscope (SEM), exhibits favorable flatness as shown in Fig. 2.

In addition, when an ultraviolet-visible spectroscopic evaluation device is used to measure spectroscopic characteristics of the layered organic perovskite material, the absorbance has a peak around 522 nm as shown in Fig. 3, for example. As shown in Fig. 3, in regard to 522 nm at which the absorbance reaches a peak, the light absorption coefficient α per thickness is approximately 80000, it has been confirmed that the material has a high absorption coefficient, and from the perspective of spectroscopic characteristics, it has been demonstrated that the material is a material preferred for the photoelectric conversion element 21 for G (green), for example.

Furthermore, when an Incident Photon to Current Conversion Efficiency (IPCE) spectrum device is used to obtain an external quantum efficiency with respect to wavelength, it is demonstrated that the photoelectric conversion efficiency (= external quantum efficiency: EQE) reaches approximately 30% around 522 nm as shown in Fig. 4, and it is demonstrated that a favorable photoelectric conversion efficiency is obtained. As a result, it is demonstrated that also from the perspective of photoelectric conversion efficiency, the layered organic perovskite material is a material preferred for the photoelectric conversion element 21 for G (green).

It is to be noted that Fig. 4 shows photoelectric conversion characteristics at a negative bias of -0.2 V IPCE for the photoelectric conversion element 21 in the solid state imaging element 11. The photoelectric conversion characteristics of IPCE in Fig. 4 reflects the spectroscopic characteristics of the layered organic perovskite material in Fig. 3, and shows that visible light of 500 to 520 nm is selectively photoelectrically converted.

When a photoelectric conversion element using the layered organic perovskite material with these features is provided as, for example, the uppermost photoelectric conversion element 21 of the vertically spectroscopic first solid state imaging element 11 shown in the upper left part of Fig. 1, the element will selectively absorb only light of wavelengths from 500 to 520 nm, and transmit light of from 450 to 500 nm and 540 nm or more, and thus function as a preferred photoelectric conversion element for G (green).

Likewise, it also becomes possible to insert the photoelectric conversion element 21 between the other

photoelectric conversion elements

22, 32 or 22, 23 that form the vertically spectroscopic solid state imaging element, as shown by the second solid state imaging element 11 in the upper central part of Fig. 1 or the third solid state imaging element 11 in the upper right thereof.

In addition, when a dark current and a light current are measured for voltage-current characteristics with the layered organic perovskite material, a result is obtained as shown in Fig. 5. More specifically, as shown in Fig. 5, favorable diode characteristics are shown in regard to the dark current in a condition shielded from light, whereas an increase in current is shown in regard to the light current in a condition irradiated with light, and it is thus demonstrated that the element functions as a photoelectric conversion element.

It is to be noted that Fig. 5 shows voltage-current characteristics of dark current and light current at a negative bias of -0.2 V IPCE for the photoelectric conversion element 21 in the solid state imaging element 11, where a dotted line represents a dark current, whereas a solid line represents a light current.

<Configuration Example of Photoelectric Conversion Element using Layered Organic Perovskite Material>
Next, a configuration example of the photoelectric conversion elements 21 to 23 using the layered organic perovskite material will be described with reference to Fig. 6. It is to be noted that while the photoelectric conversion element 21 which selectively achieves the photoelectric conversion of light of G (green) will be representatively described herein among the photoelectric conversion elements 21 to 23, the same applies to the

photoelectric conversion elements

22, 23.

For the lowermost layer in the figure, a glass layer 51 is provided, and on top thereof, an electrode layer 52 is formed which includes ATO (antimony doped tin oxide)/ITO (indium tin oxide) as a transparent conductive material.

Over the electrode layer 52, a Compact TiO2 layer 53 is formed as an electron transport layer. It is to be noted that the Compact TiO2 layer 53 may be a layer including other material as long as an electron transport layer is formed, and may be, for example, a layer formed from NiO, WO3, or TA2O5.

Over the Compact TiO2 layer 53, a porous TiO2 layer 54 is formed. Over the porous (Porous) TiO2 layer 54, a 2D Perovskite (layered organic perovskite material) layer 55 is formed which serves as a photoelectric conversion element layer. Over the 2D Perovskite layer 55, a Spiro-OMeTAD layer 56 is formed which serves as a hole transport layer. In this regard, the Spiro-OMeTAD is a compound 1 represented by the following chemical formula (1).

… Chemical Formula (1)

The Spiro-OMeTAD layer 56 may be a layer including other material as long as an hole transport layer is formed, and may be, for example, a layer formed from TiO2, ZnO, or SnO2. Over the Spiro-OMeTAD layer 56, a MoOx layer 57 is formed, and an Au layer 58 is further formed thereon.

<Method for Manufacturing Photoelectric Conversion Element using Layered Organic Perovskite Material>
Next, a method for manufacturing a photoelectric conversion element using a layered organic perovskite material will be described with reference to the flowchart in Fig. 7.

In a step S11, the 25 mm material of the ITO/ATO layer 52 and the glass layer 51 stacked is etched by a width of 5 mm on each side to partially remove the ITO/ATO layer 52. Furthermore, the glass layer 51 is subjected to ultrasonic cleaning (neutral detergent cleaning, distilled water cleaning, isopropyl alcohol cleaning, or acetone cleaning), and further subjected to UV ozone pretreatment.

In a step S12, onto the side with the above-mentioned ITO/ATO layer 52 stacked, an ethanol solution (2.5%) with Ti isopropoxide dissolved therein is applied with the use of a spray method, and thereafter, heated in an electric furnace at 500°C and for 20 minutes to form the Compact TiO2 layer 53 which serves as an electron transport layer. The Compact TiO2 layer 53 has a film thickness, for example, on the order of 30 nm.

More specifically, the electron transport layer is preferably a layer including a porous electron transport material. One, or two or more of, for example, TiO2, WO3, ZnO, Nb2O5, Ta2O5, SrTiO3 and organic electron transport materials and the like can be adopted as the porous electron transport material. It is to be noted that in the case of using an inorganic semiconductor, the semiconductor may be doped with a donor. Furthermore, in the case of using an organic electron transport material, the electron transport layer preferably has a thickness on the order of 10 to 2000 nm, more preferably 20 to 1500 nm. The thickness of the electron transport layer within the range mentioned above can further ensure that a leakage current is suppressed, and collect electrons from the light absorption layer.

In a step S13, a TiO2 paste is applied by spin coating onto the Compact TiO2 layer 53, and thereafter, heated at 500°C and for 20 minutes to form the porous TiO2 layer 54. The porous TiO2 layer 54 is, for example, on the order of 160 nm.

In a step S14, an ink with a layered organic perovskite material dissolved therein is applied by spin coating onto the porous TiO2 layer 54, and thereafter, heated at 100°C and for 5 minutes to form the 2D Perovskite layer 55 configured to have a layered organic perovskite thin film. Thereafter, the 2D Perovskite layer 55 on the part etched by the treatment in the step S11 is removed by wiping.

In a step S15, an ink obtained by mixing 1.82 ml of chlorobenzene, 14.7 mg of Spiro-OMeTAD, 17 mg of Li-TFSI, and 49 mg of 4-tert-butylpyridine is applied by spin coating onto the 2D Perovskite layer 55, thereby forming the Spiro-OMeTAD layer 56 to serve as a hole transport layer.

In a step S16, on the Spiro-OMeTAD layer 56, the MoOx layer 57 and the Au layer 58 are formed by vapor deposition with a vapor deposition machine. In this regard, the MoOx layer 57 has a film thickness of, for example, on the order of 30 nm, and the film thickness of the Au layer 58 is made by vapor deposition to have a thickness, for example, on the order of 100 nm.

More specifically, in the photoelectric conversion film applied to a solid state imaging element according to an embodiment of the present technology, a hole transport layer is provided on one side of the light absorption layer. Materials for use in the hole transport layer include, besides spiro-MeO-TAD, selenium, iodides such as copper iodide (CuI), cobalt complexes such as layered cobalt oxides, CuSCN, MoO3, NiO, WO3, and organic hole transport materials.

More specifically, the iodides include, for example, copper iodide (CuI). The layered cobalt oxides include, for example, AxCoO2 (A = Li, Na, K, Ca, Sr, Ba; 0 ≦ x ≦ 1). In addition, the organic hole transport materials include, for example, polythiophene derivatives such as poly-3-hexylthiophene (P3HT) and polyethylene dioxythiophene (PEDOT); fluorene derivatives such as 2,2',7,7'-tetrakis-(N,N-di-p-methoxyphenylamine)-9,9'-spirobifluorene (spiro-MeO-TAD); carbazole derivatives such as polyvinyl carbazole; triphenylamine derivatives; diphenyl amine derivatives; polysilane derivatives; and polyaniline derivatives. The thickness of the hole transport layer is not particularly limited, but preferably on the order of 0.01 to 10 μm.

In addition, the hole transport layer mentioned above can be formed by not only coating methods, but also non-vacuum processes such as plating methods and spray methods, and furthermore, it is possible to form the layer even by an vapor deposition process. Furthermore, the hole transport layer desirably has an electron blocking ability. Alternatively, when the hole transport layer has no electron blocking property, a second hole transport layer that has an electron blocking property may be provided for one more layer.

Furthermore, an example has been described above in which the treatment through a coating process is applied in forming each of the Compact TiO2 layer 53, the porous TiO2 layer 54, the 2D Perovskite layer 55, and the Spiro-OMeTAD layer 56. However, other approach may be adopted as long as the approach is able to form these layers, and for example, may be a vapor deposition process, a transfer process, an Atomic Layer Deposition (ALD) method, a sputtering method, and a Pulsed Laser Deposition (PLD) method.

In addition, the film thicknesses of the respective layers described above by way of example may fall within predetermined ranges, and for example, a preferred film thickness range of the Compact TiO2 layer 53 is a range of 2 nm to 100 nm. In addition, a preferred film thickness range of the porous TiO2 layer 54 is a range of 50 nm to 300 nm. Furthermore, a preferred film thickness range of the 2D Perovskite layer 55 as a photoelectric conversion layer is a range of 300 nm to 1000 nm. In addition, a preferred film thickness range of the Spiro-OMeTAD layer 56 as a hole transport layer is a range of 50 nm to 300 nm.

The treatment described above makes it possible to produce the photoelectric conversion element 21 using a photoelectric conversion film material that has high selectivity and great photoelectric conversion characteristics with respect to light of a specific wavelength.

<Control of Characteristics on Layered Organic Perovskite ((RNH3)n-Metal-X(2n)) Material>
The layered organic perovskite ((RNH3)n-Metal-X(2n)) material can control the maximum peak at absorption wavelengths and the profile of the absorption wavelengths, in combination with at least one or more of aromatic or heterocyclic compounds having a primary amine for R. In addition, likewise, the layered organic perovskite ((RNH3)n-Metal-X(2n)) material can control the maximum peak at absorption wavelengths and the profile of the absorption wavelengths, in combination with the halogen containing at least one or more of F, Cl, Br, and I for X.

As for R, for example, any of the compounds 2 to 25 expressed by the following chemical formulas (2) to (25), or a combination thereof can control the maximum peak at absorption wavelengths and the distribution profile of the absorption wavelengths for the layered organic perovskite ((RNH3)n-Metal-X(2n)) material.

… Chemical Formula (2)

… Chemical Formula (3)

… Chemical Formula (4)

… Chemical Formula (5)

… Chemical Formula (6)

… Chemical Formula (7)

… Chemical Formula (8)

… Chemical Formula (9)

… Chemical Formula (10)

… Chemical Formula (11)

… Chemical Formula (12)

… Chemical Formula (13)

… Chemical Formula (14)

… Chemical Formula (15)

… Chemical Formula (16)

… Chemical Formula (17)

… Chemical Formula (18)

… Chemical Formula (19)

… Chemical Formula (20)

… Chemical Formula (21)

… Chemical Formula (22)

… Chemical Formula (23)

… Chemical Formula (24)

… Chemical Formula (25)

Accordingly, various combinations of R that is the aromatic or heterocyclic compound having the primary amine and the halogen X can control the characteristics, thus making it possible to produce, for example, not only the photoelectric conversion element 21 which selectively achieves the photoelectric conversion of light of G (green), but also the

photoelectric conversion elements

22, 23 which have high selectivity and great photoelectric conversion characteristics with respect to B (blue) or R (red).

In addition, while the first to third solid state imaging elements 11 in Fig. 1 are intended to provide examples of a solid state imaging element for a light source including three colors of RGB (red, green, blue), the production of a photoelectric conversion film including a layered organic perovskite ((RNH3)n-Metal-X(2n)) material that selectively achieves the photoelectric conversion of light of a corresponding color (light of a corresponding wavelength) makes it possible to produce a photoelectric conversion element that selectively achieves the photoelectric conversion of the corresponding light, even in the case of combining colors with the use of other color than the RGB. For example, the production of a photoelectric conversion element through the production of a layered organic perovskite ((RNH3)n-Metal-X(2n)) material that selectively achieves the photoelectric conversion of light corresponding to wavelengths of yellow as a light source makes it also possible to capture images with, as a light source, four colors of Y (yellow) in addition to the three colors of RGB (red, green, blue).

<Configuration of Solid State Imaging Element>
Next, configurations of a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied will be described with reference to Figs. 8 and 9. Figs. 8A to 8C are schematic diagrams illustrating structures of a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied.

In this regard, in Figs. 8A to 8C,

pixel regions

201, 211, 231 refer to regions in which photoelectric conversion elements including photoelectric conversion films according to an embodiment of the present technology are disposed. In addition,

control circuits

202, 212, 242 refer to arithmetic processing circuits that control each component of the solid state imaging element, and

logic circuits

203, 223, 243 refer to signal processing circuits for processing signals photoelectrically converted by the photoelectric conversion elements in the pixel regions.

For example, as shown by a configuration A in Fig. 8, the solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied may have the pixel region 201, the control circuit 202, and the logic circuit 203 formed in one semiconductor chip 200.

In addition, as shown by a configuration B in Fig. 8, the solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied may be a stacked solid state imaging element that has the pixel region 211 and the control circuit 212 formed in a first semiconductor chip 210, and the logic circuit 223 formed in a second semiconductor chip 220.

Furthermore, as shown by a configuration C in Fig. 8, the solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied may be a stacked solid state imaging element that has the pixel region 231 formed in a first semiconductor chip 230, and the control circuit 242 and the logic circuit 243 formed in a second semiconductor chip 240.

The solid state imaging elements shown by the configurations B and C in Fig. 8 have at least either one of the control circuit and the logic circuit formed in a semiconductor chip that is separate from the semiconductor chip with the pixel region formed. Accordingly, the solid state imaging elements shown by the configurations B and C in Fig. 8 can achieve the pixel regions expanded more than the solid state imaging element shown by the configuration A, and thus increase on-board pixels in the pixel regions, and improve the planar resolution. Therefore, the solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied is more preferably the stacked solid state imaging element as shown by the configurations B and C in Fig. 8.

Subsequently, a specific structure of a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied will be described with reference to Fig. 9. Fig. 9 is a cross-sectional view illustrating an outline per unit pixel in a solid state imaging element to which a photoelectric conversion element according to an embodiment of the present technology is applied. It is to be noted that the solid state imaging element 300 shown in Fig. 9 is a rear-surface irradiated solid state imaging element to which light is incident from the other surface opposite to a surface with a pixel transistor, etc. formed. In addition, in Fig. 9, the upper side with respect to the drawing serves as a light-receiving surface, whereas the lower side serves as a circuit formation surface with a pixel transistor and a peripheral circuit formed.

As shown in Fig. 9, the solid state imaging element 300 is configured to have, in a photoelectric conversion region 320, a photoelectric conversion element including a first photodiode PD1 formed in a semiconductor substrate 330, a photoelectric conversion element including a second photodiode PD2 formed in the semiconductor substrate 330, and a photoelectric conversion element including an organic photoelectric conversion film 310 formed on the rear side of the semiconductor substrate 330, which are stacked in the light incident direction.

The first photodiode PD1 and the second photodiode PD2 are formed in a well region 331 that is a first conductivity-type (for example, p-type) semiconductor region of the semiconductor substrate 330 including silicon.

The first photodiode PD1 has an n-type semiconductor region 332 with a second conductivity-type (for example, n-type) impurity, which is formed on the light-receiving side of the semiconductor substrate 330, and an extended part 332a formed by extending a portion of the n-type semiconductor region 332 so as to reach the surface of the semiconductor substrate 330. On the surface of the extended part 332a, a high-concentration p-type semiconductor region 334 is formed which serves as a charge accumulation layer. In addition, the extended part 332a is formed as an extraction layer for extracting a signal charge accumulated in the n-type semiconductor region 332 of the first photodiode PD1, to the surface of the semiconductor substrate 330.

The second photodiode PD2 is configured to have an n-type semiconductor region 336 formed on the light-receiving side of the semiconductor substrate 330, and a high-concentration p-type semiconductor region 338 formed at the surface of the semiconductor substrate 330, which serves as a charge accumulation layer.

The formation of the p-type semiconductor regions at the interface of the semiconductor substrate 330 for the first photodiode PD1 and the second photodiode PD2 can suppress the dark current generated at the interface of the semiconductor substrate 330.

In this regard, the second photodiode PD2 formed in a region furthest from the light receiving surface is, for example, a red photoelectric conversion element that absorbs red light and achieves the photoelectric conversion of the light. In addition, the first photodiode PD1 formed to be closer to the light-receiving surface than the second photodiode PD2 is, for example, a blue photoelectric conversion element that absorbs blue light and achieves the photoelectric conversion of the light.

The organic photoelectric conversion film 310 is formed over the rear surface of the semiconductor substrate 330 with an antireflection film 302 and an insulating film 306 interposed therebetween. In addition, the organic photoelectric conversion film 310 is sandwiched between an upper electrode 312 and a lower electrode 308 to form a photoelectric conversion element. In this regard, the organic photoelectric conversion film 310 is, for example, an organic film that absorbs green light and achieves the photoelectric conversion of the light, which is formed from a photoelectric conversion film according to an embodiment of the present technology described above. In addition, the upper electrode 312 and the lower electrode 308 are formed from, for example, a transparent conductive material such as an indium tin oxide (ITO) and an indium zinc oxide (IZO).

In addition, the lower electrode 308 is connected through a contact plug 304 passing through the antireflection film 302 to a vertical transfer pathway 348 formed from the rear surface of the semiconductor substrate 330 to the surface thereof. The vertical transfer pathway 348 is formed to have a stacked structure of a connection 340, a potential barrier layer 342, a charge accumulation layer 344, and a p-type semiconductor region 346 from the rear side of the semiconductor substrate 330.

The connection 340 includes an n-type impurity region with a high impurity concentration, which is formed on the rear side of the semiconductor substrate 330, and the formation of the connection 340 is intended for ohmic contact with the contact plug 304. The potential barrier layer 342 includes a low-concentration p-type impurity region, and forms a potential barrier between the connection 340 and the charge accumulation layer 344. The charge accumulation layer 344, which accumulates signal charges transferred from the organic photoelectric conversion film 310, is formed from an n-type impurity region that is lower in concentration than the connection 340. It is to be noted that the high-concentration p-type semiconductor region 346 is formed at the surface of the semiconductor substrate 330. The p-type semiconductor region 346 suppresses the dark current generated at the interface of the semiconductor substrate 330.

In this regard, a multilayer wiring layer 350 including wirings 358 of multiple layers laminated with an interlayer insulating layer 351 therebetween is formed on the surface of the semiconductor substrate 330. In addition,

readout circuits

352, 354, 356 corresponding to the first photodiode PD1, the second photodiode PD2, and the organic photoelectric conversion film 310 are formed near the surface of the semiconductor substrate 330. The

readout circuits

352, 354, 356 read out output signals from the respective photoelectric conversion elements, and transfer the signals to a logic circuit (not shown). Furthermore, a support substrate 360 is formed on the surface of the multilayer wiring layer 350.

On the other hand, light shielding films 316 are formed on the light receiving side of the upper electrode 312, so as to shield the extended part 332a of the first photodiode PD1 and the vertical transfer pathway 348 from light. In this regard, the region separated by the light shielding films 316 serves as the photoelectric conversion region 320. In addition, an on-chip lens 318 is formed over the light shielding films 316 with a planarization film 314 interposed therebetween.

The solid state imaging element 300 has been described above, to which the photoelectric conversion elements according to an embodiment of the present technology are applied. It is to be noted that the solid state imaging element 300 to which the photoelectric conversion elements according to an embodiment of the present technology has no color filter or the like formed because the color separation is achieved in a vertical direction in the unit pixel.

<Configuration of Electronic Device>
Subsequently, the configuration of an electronic device to which a photoelectric conversion element according to an embodiment of the present technology is applied will be described with reference to Fig. 10. Fig. 10 is a block diagram for explaining the configuration of an electronic device to which a photoelectric conversion element according to an embodiment of the present technology is applied.

As shown in Fig. 10, the electronic device 400 includes an optical system 402, a solid state imaging element 404, a Digital Signal Processor (DSP) circuit 406, a control unit 408, an output unit 412, an input unit 414, a frame memory 416, a recording unit 418, and a power source unit 420.

In this regard, the DSP circuit 406, the control unit 408, the output unit 412, the input unit 414, the frame memory 416, the recording unit 418, and the power source unit 420 are interconnected through a bus line 410.

The optical system 402 takes in incident light from an object, and provides an image on an imaging surface of the solid state imaging element 404. In addition, the solid state imaging element 404 includes a photoelectric conversion element according to an embodiment of the present technology, and converts the light amount of the incident light of the image provided on the imaging surface by the optical system 402, into electrical signals on a pixel-to-pixel basis, and outputs the signals as pixel signals.

The DSP circuit 406 processes the pixel signals transferred from the solid state imaging element 404, and outputs the signals to the output unit 412, the frame memory 416, and the recording unit 418, etc. The control unit 408 is configured to have, for example, an arithmetic processing circuit or the like, and controls the operation for each component of the electronic device 400.

The output unit 412 is a panel display device such as a liquid crystal display or an organic electroluminescence display, which displays moving images or static images taken by the solid state imaging element 404. It is to be noted that the output unit 412 may include an audio output device such as a speaker and a headphone. In addition, the input unit 414 is, for example, a device for a user inputting an operation, such as a touch panel and a button, which gives operation instructions for various functions of the electronic device 400 in accordance with the user operation.

The frame memory 416 temporarily stores moving images or static images, etc. taken by the solid state imaging element 404. In addition, the recording unit 418 records moving images or static images, etc. taken by the solid state imaging element 404, on a removable storage medium such as a magnetic disk, an optical disk, a magneto optical disk, or a semiconductor memory.

The power source unit 420 appropriately supplies various types of power sources that serve as power sources for the operation of the DSP circuit 406, the control unit 408, the output unit 412, the input unit 414, the frame memory 416, and the recording unit 418, to the objects to be supplied.

The electronic device 400 to which the photoelectric conversion element according to an embodiment of the present technology is applied has been described above. The electronic device 400 to which the photoelectric conversion element according to an embodiment of the present technology is applied may be, for example, an imaging device.

In addition, while the solid state imaging elements and the electronic device to which the photoelectric conversion elements according to an embodiment of the present technology is applied have been described above, it is possible to apply the elements even to other technology, and it is also possible to apply the element as, for example, a solar cell or a sensor that uses light.

While an embodiment of the present technology has been described above in detail with reference to the accompanying drawings, the technical scope of the present technology is not limited to such an example. It is obvious that those skilled in the art can conceive of various modification examples or alteration examples within the scope of the technical idea specified in the claims, and it should be understood that these examples also obviously fall within the technical scope of the present technology.

Furthermore, the advantageous effects described in this specification by way of explanatory or illustrative example only are not restrictive. More specifically, the present technology can produce, along with the advantageous effects mentioned above, or instead of the advantageous effects mentioned above, other advantageous effects that are obvious to those skilled in the art from the description in this specification.

It is to be noted that the present technology can also provide the following configurations.
(1)
A device comprising:
a photoelectric conversion layer;
a hole transport layer;
an electron transport layer; and
a pair of electrodes,
wherein the electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes, and
wherein the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
(2)
The device according to (1),
wherein the layered organic perovskite material has the chemical formula:
(RNH3)n-Metal-X(2+n)
wherein the R is at least one or more of aromatic or heterocyclic compounds having a primary amine,
the Metal is a metal containing at least one or more of Pb, Sn, and Mn,
the X is a halogen containing at least one or more of F, Cl, Br, and I, and
the n is a natural number.
(3)
The device according to (2),
wherein the structure of R controls a maximum peak at absorption wavelengths and a distribution profile of the absorption wavelengths, for light in a specific wavelength region, the light selectively absorbed by the layered organic perovskite material.
(4)
The device according to (1),
wherein the electron transport layer comprises at least one of TiO2, NiO, WO3, and TA2O5.
(5)
The device according to (1),
wherein the hole transport layer comprises at least one of Spiro-OMeTAD, TiO2, ZnO, and SnO2.
(6)
The device according to (1), wherein the layered organic perovskite material is a 2-dimensional material.
(7)
The device according to (1), wherein the layered organic perovskite material includes organic layers and inorganic layers that are stacked alternately.
(8)
The device according to (1), wherein the photoelectric conversion layer absorbs and photoelectrically converts light at wavelengths of from 500 nm to 520 nm.
(9)
The device according to (8), wherein the photoelectric conversion layer transmit light at wavelengths of from 450 nm to 500 nm.
(10)
The device according to (9), wherein the photoelectric conversion layer further transmits light at wavelengths of greater than 540 nm.
(11)
The device according to (1), wherein the electron transport layer is a compact TiO2 layer.
(12)
The device according to (11), wherein the hole transport layer is a Spiro-OMeTAD layer.
(13)
The device according to (12), further comprising:
a porous TiO2 layer, wherein the porous TiO2 layer is between the compact TiO2 layer and the layered organic perovskite material.
(14)
The device according to (13), further comprising:
a MoOx layer, wherein the MoOx layer on a side of the Spiro-OMeTAD layer opposite the layered organic perovskite material.
(15)
The device according to (1), wherein the hole transport layer is over a light incident side of the layered organic perovskite material.
(16)
The device according to (1), wherein the device includes a plurality of photoelectric conversion elements.
(17)
The device according to (16), wherein each of the photoelectric conversion elements includes a photoelectric conversion layer, a hole transport layer, and an electron transport layer.
(18)
The device according to (17), wherein a first one of the photoelectric conversion elements photoelectrically converts green light, wherein a second one of the photoelectric conversion elements photoelectrically converts blue light, and wherein the second photoelectric conversion element is stacked on top of the first photoelectric conversion element.
(19)
A method for manufacturing a solid state imaging element, the method comprising:
forming a first electrode;
forming, on top of the first electrode, an electron transport layer that transports an electron from a photoelectric conversion layer;
forming, on top of the electron transport layer, the photoelectric conversion layer including a layered organic perovskite material that selectively absorbs light only in a specific wavelength region;
forming, on top of the photoelectric conversion layer, a hole transport layer that transports a hole to the photoelectric conversion layer to achieve photoelectric conversion of incident light; and
forming a second electrode on top of the hole transport layer.
(20)
An electronic apparatus comprising:
a plurality of photoelectric conversion elements;
a plurality of pixel regions, wherein at least one photoelectric conversion element is disposed in each pixel region, and wherein each photoelectric conversion element includes:
a photoelectric conversion layer;
a hole transport layer;
an electron transport layer; and
a pair of electrodes,
wherein the electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes, and
wherein the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region;
a control circuit; and
a logic circuit.
(21)
A solid state imaging element including:
a photoelectric conversion layer that achieves photoelectric conversion of incident light;
a hole transport layer that transports a hole to the photoelectric conversion layer;
an electron transport layer that transports an electron to the photoelectric conversion layer; and
a pair of electrodes,
wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and
the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
(22)
The solid state imaging element of (21),
wherein the layered organic perovskite material is represented by:
(RNH3)n-Metal-X(2+n)
the R represents at least one or more of aromatic or heterocyclic compounds having a primary amine,
the Metal represents a metal containing at least one or more of Pb, Sn, and Mn,
the X represents a halogen containing at least one or more of F, Cl, Br, and I, and
the n is a natural number.
(23)
The solid state imaging element of (22),
wherein the structure of R controls a maximum peak at absorption wavelengths and a distribution profile of the absorption wavelengths, for light in a specific wavelength region, the light selectively absorbed by the layered organic perovskite material.
(24)
The solid state imaging element of any of (21) to (23),
wherein the electron transport layer includes any of TiO2, NiO, WO3, and TA2O5.
(25)
The solid state imaging element of any of (21) to (24),
wherein the hole transport layer includes any of Spiro-OMeTAD, TiO2, ZnO, and SnO2.
(26)
A method for manufacturing a solid state imaging element, the method including:
a first step of forming a first electrode;
a second step of forming, on top of the first electrode, an electron transport layer that transports an electron to a photoelectric conversion layer;
a third step of forming, on top of the electron transport layer, the photoelectric conversion layer including a layered organic perovskite material that selectively absorbs light only in a specific wavelength region;
a fourth step of forming, on top of the photoelectric conversion layer, a hole transport layer that transports a hole to the photoelectric conversion layer to achieve photoelectric conversion of incident light; and
a fifth step of forming a second electrode on top of the hole transport layer.
(27)
A photoelectric conversion element including:
a photoelectric conversion layer that achieves photoelectric conversion of incident light;
a hole transport layer that transports a hole to the photoelectric conversion layer;
an electron transport layer that transports an electron to the photoelectric conversion layer; and
a pair of electrodes,
wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and
the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
(28)
An imaging device including:
a photoelectric conversion layer that achieves photoelectric conversion of incident light;
a hole transport layer that transports a hole to the photoelectric conversion layer;
an electron transport layer that transports an electron to the photoelectric conversion layer; and
a pair of electrodes,
wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and
the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
(29)
An electronic device including:
a photoelectric conversion layer that achieves photoelectric conversion of incident light;
a hole transport layer that transports a hole to the photoelectric conversion layer;
an electron transport layer that transports an electron to the photoelectric conversion layer; and
a pair of electrodes,
wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and
the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
(30)
A photoelectric conversion element including:
a photoelectric conversion layer that achieves photoelectric conversion of incident light;
a hole transport layer that transports a hole to the photoelectric conversion layer;
an electron transport layer that transports an electron to the photoelectric conversion layer; and
a pair of electrodes,
wherein the photoelectric conversion layer, the hole transport layer, and the electron transport layer are stacked between the pair of electrodes, and
the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.

11 solid state imaging element
21 to 23 photoelectric conversion element (photoelectric conversion film)
31, 32 photoelectric conversion element (photodiode)
51 glass layer
52 electrode layer
53 Compact TiO2 layer
54 porous TiO2 layer
55 2D Perovskite layer
56 Spiro-OMeTAD layer
57 MoOx layer
58 Au layer

Claims

A device comprising:
a photoelectric conversion layer;
a hole transport layer;
an electron transport layer; and
a pair of electrodes,
wherein the electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes, and
wherein the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region.
The device according to claim 1,
wherein the layered organic perovskite material has the chemical formula:
(RNH3)n-Metal-X(2+n)
wherein the R is at least one or more of aromatic or heterocyclic compounds having a primary amine,
the Metal is a metal containing at least one or more of Pb, Sn, and Mn,
the X is a halogen containing at least one or more of F, Cl, Br, and I, and
the n is a natural number.
The device according to claim 2,
wherein the structure of R controls a maximum peak at absorption wavelengths and a distribution profile of the absorption wavelengths, for light in a specific wavelength region, the light selectively absorbed by the layered organic perovskite material.
The device according to claim 1,
wherein the electron transport layer comprises at least one of TiO2, NiO, WO3, and TA2O5.
The device according to claim 1,
wherein the hole transport layer comprises at least one of Spiro-OMeTAD, TiO2, ZnO, and SnO2.
The device according to claim 1, wherein the layered organic perovskite material is a 2-dimensional material.
The device according to claim 1, wherein the layered organic perovskite material includes organic layers and inorganic layers that are stacked alternately.
The device according to claim 1, wherein the photoelectric conversion layer absorbs and photoelectrically converts light at wavelengths of from 500 nm to 520 nm.
The device according to claim 8, wherein the photoelectric conversion layer transmit light at wavelengths of from 450 nm to 500 nm.
The device according to claim 9, wherein the photoelectric conversion layer further transmits light at wavelengths of greater than 540 nm.
The device according to claim 1, wherein the electron transport layer is a compact TiO2 layer.
The device according to claim 11, wherein the hole transport layer is a Spiro-OMeTAD layer.
The device according to claim 12, further comprising:
a porous TiO2 layer, wherein the porous TiO2 layer is between the compact TiO2 layer and the layered organic perovskite material.
The device according to claim 13, further comprising:
a MoOx layer, wherein the MoOx layer on a side of the Spiro-OMeTAD layer opposite the layered organic perovskite material.
The device according to claim 1, wherein the hole transport layer is over a light incident side of the layered organic perovskite material.
The device according to claim 1, wherein the device includes a plurality of photoelectric conversion elements.
The device according to claim 16, wherein each of the photoelectric conversion elements includes a photoelectric conversion layer, a hole transport layer, and an electron transport layer.
The device according to claim 17, wherein a first one of the photoelectric conversion elements photoelectrically converts green light, wherein a second one of the photoelectric conversion elements photoelectrically converts blue light, and wherein the second photoelectric conversion element is stacked on top of the first photoelectric conversion element.
A method for manufacturing a solid state imaging element, the method comprising:
forming a first electrode;
forming, on top of the first electrode, an electron transport layer that transports an electron from a photoelectric conversion layer;
forming, on top of the electron transport layer, the photoelectric conversion layer including a layered organic perovskite material that selectively absorbs light only in a specific wavelength region;
forming, on top of the photoelectric conversion layer, a hole transport layer that transports a hole to the photoelectric conversion layer to achieve photoelectric conversion of incident light; and
forming a second electrode on top of the hole transport layer.
An electronic apparatus comprising:
a plurality of photoelectric conversion elements;
a plurality of pixel regions, wherein at least one photoelectric conversion element is disposed in each pixel region, and wherein each photoelectric conversion element includes:
a photoelectric conversion layer;
a hole transport layer;
an electron transport layer; and
a pair of electrodes,
wherein the electron transport layer, the photoelectric conversion layer, and the hole transport layer are stacked between the pair of electrodes, and
wherein the photoelectric conversion layer includes a layered organic perovskite material that selectively absorbs light only in a specific wavelength region;
a control circuit; and
a logic circuit.