KR20180106851A - Photoelectric conversion device including perovskite compound and imaging device including the same - Google Patents

Abstract

A photoelectric conversion device including a perovskite compound and an image apparatus including the same are disclosed. The photoelectric conversion device includes a first conductive layer, a second conductive layer, a photoelectric conversion layer interposed between the first conductive layer and the second conductive layer, an electron blocking layer interposed between the photoelectric conversion layer and the first conductive layer, and a hole blocking layer interposed between the photoelectric conversion layer and the second conductive layer. Accordingly, the present invention can improve photoelectric conversion efficiency and reduce a dark current.

Description

TECHNICAL FIELD The present invention relates to a photoelectric conversion device including a perovskite compound and an imaging device including the perovskite compound,

The present invention relates to a photoelectric conversion device including a perovskite compound and an imaging device including the same.

A photoelectric conversion device refers to an element that converts an optical signal into an electrical signal. Typically, a photoelectric conversion element utilizes a photoelectric effect such as a photoconductive effect and a photovoltaic effect when converting an optical signal into an electric signal.

As one example, the photoelectric conversion element can be used in an image pickup apparatus. The image pickup apparatus can use a scheme in which the photoelectric conversion elements are two-dimensionally arranged on the transistors and the electric signals generated in the respective photoelectric conversion elements are collected.

A photoelectric conversion element including a perovskite compound, and an imaging apparatus including the same. And more particularly, to a photoelectric conversion device including a perovskite compound in an electron blocking layer and a hole blocking layer, respectively, and an imaging device including the same.

According to an aspect, there is provided a semiconductor device comprising: a first conductive layer; A second conductive layer; A photoelectric conversion layer interposed between the first conductive layer and the second conductive layer; An electron blocking layer interposed between the photoelectric conversion layer and the first conductive layer; And a hole blocking layer interposed between the photoelectric conversion layer and the second conductive layer,

Wherein the electron blocking layer comprises a first perovskite compound represented by the following formula (1)

Wherein the hole blocking layer comprises a second perovskite compound represented by the following Formula 2:

≪ Formula 1 >

[A ¹ ] [B ¹ ] [X ¹ _(3-n) Y ¹ _n ]

In Formula 1,

A ¹ is at least one monovalent organic-cation, monovalent inorganic-cation or any combination thereof,

B ¹ is at least one divalent inorganic-cation,

X ¹ and Y ¹ are, independently of each other, at least one monovalent anion,

n is a real number satisfying 0? n? 3,

(2)

[A ² ] [B ² ] [X ² _(3-m) Y ² _m ]

In Formula 2,

A ² is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,

B ² is at least one divalent inorganic-cation,

X ² and Y ² are, independently of each other, at least one monovalent anion,

m is a real number satisfying 0? m? 3.

According to another aspect of the present invention, there is provided a method of manufacturing a semiconductor device, comprising: forming an electron blocking layer including a first perovskite compound represented by Formula 1 on a first conductive layer;

Forming a photoelectric conversion layer on the electron blocking layer;

Forming a hole blocking layer containing a second perovskite compound represented by Formula 2 on the photoelectric conversion layer; And

Forming a second conductive layer on the hole blocking layer; and forming a second conductive layer on the hole blocking layer.

According to another aspect, A photodetector; And a control unit, wherein the photodetector includes the above-mentioned photoelectric conversion element.

It is possible to provide a photoelectric conversion element having improved photoelectric conversion efficiency and reduced dark current. Further, a high-quality imaging apparatus can be provided.

BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is a schematic cross-sectional side view of a photoelectric conversion element according to an embodiment. FIG.
2A and 2B are diagrams schematically showing energy levels of the photoelectric conversion layer and the electron blocking layer.
3A and 3B are diagrams schematically showing the energy levels of the photoelectric conversion layer and the hole blocking layer.
4 is a diagram schematically showing a method of driving a photoelectric conversion element according to an embodiment.
5 is a cross-sectional view schematically showing a method for manufacturing a photoelectric conversion element according to an embodiment.
6 is a photograph showing the surface of (a) the electron blocking layer, (b) the photoelectric conversion layer, and (c) the hole blocking layer in Example 1, respectively.
7 is a graph showing experimental results of Examples 1 to 3 and Comparative Examples 1 and 2 according to Evaluation Example 1. Fig.
8 is a graph showing the experimental results of Comparative Examples 3 and 4 according to Evaluation Example 2. Fig.
9 is a graph showing the experimental results of Example 2 according to the evaluation example 3. Fig.
FIGS. 10A and 10B are graphs showing the results of photoelectronic characteristics of Comparative Example 1 and Comparative Example 5 according to Evaluation Example 4. FIG.
11 is a scanning electron microscope (SEM) photograph of the electron blocking layer of Example 1. Fig.
12 is a scanning electron microscope (SEM) photograph of the photoelectric conversion layer of Example 1. Fig. (B) is an enlarged view of (a), (c) is an enlarged view of (b), and the scale bar is 400 占 퐉.
13 is a scanning electron microscope (SEM) photograph of the hole blocking layer of Example 1. Fig.
14 is a scanning electron microscope (SEM) photograph of the hole blocking layer of Example 2. Fig. (B) is an enlarged view of (a).

BRIEF DESCRIPTION OF THE DRAWINGS The present invention is capable of various modifications and various embodiments, and specific embodiments are illustrated in the drawings and described in detail in the detailed description. The effects and features of the present invention and methods of achieving them will be apparent with reference to the embodiments described in detail below with reference to the drawings. However, the present invention is not limited to the embodiments described below, but may be implemented in various forms.

Hereinafter, a photoelectric conversion element, a method of driving the same, and a method of manufacturing the same will be described in detail with reference to the accompanying drawings. In the following drawings, like reference numerals refer to like elements, and the size of each element in the drawings may be exaggerated or reduced for convenience of explanation and convenience.

In addition, in the following embodiments, when various elements such as a layer, a film, and the like are referred to as being " on " another element, not only when directly contacting other elements, but also when other elements are interposed therebetween .

The terms first, second, etc. in this specification are used for the purpose of distinguishing one element from another element, rather than limiting.

As used herein, the terminology used herein is intended to encompass all commonly used generic terms that may be considered while considering the functionality of the present invention, but this may vary depending upon the intent or circumstance of the skilled artisan, the emergence of new technology, and the like. Also, in certain cases, there may be a term selected arbitrarily by the applicant, in which case the meaning thereof will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present specification should be defined based on the meaning of the terms, not on the names of simple terms, and on the contents throughout the specification.

In the present specification, " perovskite compound " can be represented, for example, by the formula ABX ₃ wherein A and B are each a cation of a different size from each other, and X is an anion. In the unit cell, the A cations are located at (0, 0, 0), the B cations are located at (1/2, 1/2, 1/2), the X anions are located at (1/2, Lt; / RTI > Depending on the kind of A, B and X, it may have a twisted structure having a lower symmetry than the ideal symmetric structure of CaTiO _{3. In} this specification, it is understood that the twisted structure having not only an ideal symmetry structure but also a low symmetry do.

1 schematically shows a side sectional view of a photoelectric conversion element 100 according to an embodiment of the present invention.

The photoelectric conversion element 100 includes a first conductive layer 110; A second conductive layer 150; An electron blocking layer (120); A photoelectric conversion layer 130; And a hole blocking layer 140.

The electron blocking layer 120, the photoelectric conversion layer 130 and the hole blocking layer 140 are interposed between the first conductive layer 110 and the second conductive layer 150.

The electron blocking layer 120 is interposed between the first conductive layer 110 and the photoelectric conversion layer 130.

The hole blocking layer 140 is interposed between the second conductive layer 150 and the photoelectric conversion layer 130.

The electron blocking layer 120 includes a first perovskite compound represented by the following Formula 1:

≪ Formula 1 >

[A ¹ ] [B ¹ ] [X ¹ _(3-n) Y ¹ _n ]

In Formula 1, A ¹ may be at least one monovalent organic-cation, monovalent inorganic-cation, or any combination thereof.

For example, in the general formula (1), A ¹ is a group selected from the group consisting of i) one monovalent organic cation, ii) one monovalent inorganic cation, iii) two or more monovalent organic- But are not limited to, two or more different monovalent inorganic-cation, or v) a combination of one or more monovalent organic-cations and one or more monovalent inorganic-cation.

As another example, In the formula 1, A ¹ is _{(R 1 R 2 R 3 C} ) +, (R 1 R 2 R 3 R 4 N) +, (R 1 R 2 R 3 R 4 P) +, ( _{R 1 R 2 R 3 R 4} As) +, (R 1 R 2 R 3 R 4 Sb) +, (R 1 R 2 N = C (R 3) -NR 4 R 5) +, substituted or unsubstituted nitrogen-containing five-membered monovalent cation, a substituted or unsubstituted with 1 the cations of nitrogen 6-membered ring, a substituted or unsubstituted monovalent unsubstituted 7-membered ring cations, Li ^+, Na ^+, K ^+, Rb ^+, Cs ^+, Fr ^+, or any combination thereof,

Wherein R ₁ to R _5, the substituted, at least one of the first nitrogen of 5-membered ring substituent of the cation, the substituted, at least one of the one of the nitrogen 6-membered ring substituent of the cation and the monovalent cations of the substituted 7-membered ring (-D), -F, -Cl, -Br, -I, a hydroxyl group, a substituted or unsubstituted C ₁ -C ₁₀ alkyl group, a substituted or unsubstituted aryl group, A substituted or unsubstituted C ₂ -C ₁₀ alkenyl group, a substituted or unsubstituted C ₂ -C ₁₀ alkynyl group, a substituted or unsubstituted C ₁ -C ₁₀ alkoxy group, a substituted or unsubstituted C ₆ -C ₂₀ aryl group, and -N (Q ₁ ) (Q ₂ )

Wherein Q ₁ and Q ₂ independently represent hydrogen, deuterium, a hydroxyl group, a C ₁ -C ₂₀ alkyl group, a C ₂ -C ₂₀ alkenyl group, a C ₂ -C ₂₀ alkynyl group, a C ₁ -C ₂₀ alkoxy group, C ₆ -C ₂₀ aryl groups, but are not limited thereto.

As yet another example, In the formula 1, A ¹ is _{(R 1 R 2 R 3 C} ) +, (R 1 R 2 R 3 R 4 N) +, (R 1 R 2 R 3 R 4 P) +, _{(R 1 R 2 R 3 R} 4 As) +, (R 1 R 2 R 3 R 4 Sb) +, (R 1 R 2 N = C (R 3) -NR 4 R 5) +, substituted or unsubstituted Substituted or unsubstituted imidazolium, substituted or unsubstituted pyridinium, substituted or unsubstituted pyridazinium, substituted or unsubstituted pyrimidinium, substituted or unsubstituted imidazolium, A substituted or unsubstituted pyrazolinium, a substituted or unsubstituted thiazolium, a substituted or unsubstituted oxazolium, a substituted or unsubstituted piperidinium, a substituted or unsubstituted pyrrolidinium ), Substituted or unsubstituted pyrrolinium, substituted or unsubstituted pyrrolium, substituted or unsubstituted triazolium, substituted or unsubstituted cycloheptatridienium, Li ⁺ , Na ⁺ , ^{K +, Rb +, Cs +} , Fr + , or any combination thereof And;

At least one of the substituents of R ₁ to R ₅ , the substituted imidazolium, at least one of the substituents of the substituted pyridinium, at least one of the substituents of the substituted pyridazinium, the substituent of the substituted pyrimidinium , At least one of the substituents of the substituted pyrazinium, at least one of the substituents of the substituted pyrazolium, at least one of the substituents of the substituted thiazolium, at least one of the substituents of the substituted oxazolium, At least one of the substituents of the substituted pyrrolidinium, at least one of the substituents of the substituted pyrrolidinium, at least one of the substituents of the substituted pyrrolidinium, at least one of the substituted pyrrolidinium, at least one of the substituted pyrrolidinium, At least one of the substituents of the zolmium is, independently of each other,

C ₁ -C ₂₀ alkyl group, C ₂ -C ₁₀ alkenyl group, C ₂ -C ₁₀ alkynyl group, and C ₁ -C ₂₀ alkoxy group such as hydrogen, deuterium, -F, -Cl, -Br, -I, ;

C ₁ -C ₂₀ alkyl group, C ₂ -C ₁₀ alkenyl group, C ₂ -C ₁₀ alkynyl group and C ₁ -C ₁₀ alkynyl group, which is substituted with at least one selected from deuterium, -F, -Cl, -Br, -I and a hydroxyl group, A C ₂₀ alkoxy group;

A phenyl group, a naphthyl group, a biphenyl group and a terphenyl group;

Selected from the group consisting of hydrogen, deuterium, -F, -Cl, -Br, -I, a hydroxyl group, a C ₁ -C ₂₀ alkyl group, a C ₂ -C ₁₀ alkenyl group, a C ₂ -C ₁₀ alkynyl group and a C ₁ -C ₂₀ alkoxy group A phenyl group, a naphthyl group, a biphenyl group and a terphenyl group substituted with at least one group; And

_{-N (Q 1) (Q 2} );

≪ / RTI >

Wherein Q ₁ and Q ₂ independently represent hydrogen, deuterium, C ₁ -C ₂₀ alkyl, C ₂ -C ₁₀ alkenyl, C ₂ -C ₁₀ alkynyl, C ₁ -C ₂₀ alkoxy, phenyl, naphthyl, A biphenyl group, and a terphenyl group, but is not limited thereto.

In yet another example, the general formula 1, A ¹ is _{(R 1 R 2 R 3 R} 4 N) +, (R 1 R 2 R 3 R 4 P) +, (R 1 R 2 R 3 R 4 As) ⁺ , (R ₁ R ₂ R ₃ R ₄ Sb) ⁺ , (R ₁ R ₂ N═C (R ₃ ) -NR ₄ R ₅ ) ⁺ , substituted or unsubstituted cycloheptatridinium, Li ⁺ , Na ⁺ , K ⁺ , Rb ⁺ , Cs ⁺ , Fr ⁺ or any combination thereof;

Wherein R ₁ to R ₅ and the substituted cycloheptyl at least one of the substituents of the tart Rie titanium represent, independently of each other, hydrogen, heavy hydrogen, -F, -Cl, -Br, -I, hydroxyl group, C ₁ -C ₂₀ An alkyl group, a C ₂ -C ₁₀ alkenyl group, a C ₂ -C ₁₀ alkynyl group, a C ₁ -C ₂₀ alkoxy group and -N (Q ₁ ) (Q ₂ )

Q ₁ and Q ₂ may be independently selected from hydrogen, deuterium, C ₁ -C ₂₀ alkyl group, C ₂ -C ₁₀ alkenyl group, C ₂ -C ₁₀ alkynyl group and C ₁ -C ₂₀ alkoxy group , But is not limited thereto.

In yet another example, the general formula 1, A ¹ is ^{_{(CH 3 NH 3) +,}} (C 2 H 6 PH 2) +, (CH 3 AsH 3) +, (NH 4) +, (CH 3 SbH 3 _{^{) +, (C 2 H 6}} NH 2) +, (PH 4) +, (CH 2 N 2 H 4) +, (PF 4) +, (CH 3 PH 3) +, (C 7 H 7) + ^{_{, (SbH 4) +, (}} AsH 4) +, (NCl 4) +, (NH 3 OH) +, (NH 3 NH 2) +, (CH (NH 2) 2) +, (C 3 N 2 H _{^{5) +, ((CH 3}} ) 2 NH 2) +, (NC 4 H 8) +, ((CH 3 CH 2) NH 3) +, ((NH 2) 3 C) +, ((CH 3 CH _{2 CH 2 CH 2) NH 3} ) +, (NH 2 CHNH 2) +, Li +, Na +, K +, Rb +, Cs +, may be a Fr ^+, or any combination thereof, but not limited to, .

In yet another example, the general formula 1, A ¹ is ^{_{(CH 3 NH 3) +,}} ((CH 3 CH 2 CH 2 CH 2) NH 3) +, (NH 2 CHNH 2) +, K +, Rb + , Cs ⁺ , or any combination thereof.

In Formula 1, B ¹ may be at least one divalent inorganic cation.

For example, in Formula 1, B ¹ may be i) a divalent inorganic cation-cation, or ii) a combination of two or more different divalent inorganic-cation ions, but is not limited thereto.

As another example, in the above formula (1), B ¹ may be a divalent cation of a rare earth metal, a divalent cation of an alkaline earth metal, a divalent cation of a transition metal, a divalent cation of a post-transition metal, or any combination thereof. But is not limited thereto.

As another example, in the above formula (1), B ¹ is La ²⁺ , Ce ²⁺ , Pr ²⁺ , Nd ²⁺ , Pm ²⁺ , Sm ²⁺ , Eu ²⁺ , Gd ²⁺ , Tb ²⁺ , Dy ²⁺ , Ho2 ⁺ , Er2 ⁺ , Tm2 ⁺ , Yb2 ⁺ , Lu2 ⁺ , Be2 ⁺ , Mg2 ⁺ , Ca2 ⁺ , Sr2 ⁺ , Ba2 ⁺ , Ra2 ⁺ , Pb2 ⁺ , Sn ^2+, or any combination thereof, but is not limited thereto.

As another example, in the above formula (1), B ¹ may be Pb ²⁺ , Sn ²⁺ or any combination thereof, but is not limited thereto.

As another example, in Formula 1, B ¹ may be Pb ²⁺ , but is not limited thereto.

In formula (1), X ¹ and Y ¹ may independently be at least one monovalent anion. Here, X ¹ and Y ¹ may be the same or different from each other.

For example, in the above formula (1), X ¹ and Y ¹ are independently of each other i) a monovalent anion or ii) a combination of two or more different monovalent anions, no.

As another example, in Formula 1, X ¹ and Y ¹ may independently be at least one halide anion, but are not limited thereto.

As another example, in Formula 1, X ¹ and Y ¹ may be independently selected from Cl ^- , Br ^- and I ^- , but are not limited thereto.

In Formula 1, n may be a real number satisfying 0? N? 3.

For example, in Formula 1, n may be a real number satisfying 0? N <3, but is not limited thereto.

The hole blocking layer 140 may include a second perovskite compound represented by the following Formula 2:

(2)

[A ² ] [B ² ] [X ² _(3-m) Y ² _m ]

In the formula 2, a detailed description of the A ^2, please refer to the description of A ¹ in formula (I).

In the formula 2, a detailed description of the B ^2, please refer to the description of the B ¹ of formula (I).

In the formula 2, a detailed description of X ^2, please refer to the description of the X ¹ in the formula (I).

In the above formula (2), a detailed description of Y ² is given in the description of Y ¹ in the formula (1).

For a detailed description of m in the above formula (2), see the description of n in formula (1).

In one embodiment, the first perovskite compound represented by Formula 1 and the second perovskite compound represented by Formula 2 are independently selected from the group consisting of CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbBr _{3 , CH 3 NH 3 PbBr (3} -o) I o, CH 3 NH 3 PbCl (3-o) Br o, CH 3 NH 3 PbCl (3-o) I o, CsPbI 3, CsPbBr 3, CH 3 CH 2 _{CH 2 CH 2 NH 3 PbBr 3} , NH 2 CHNH 2 PbBr 3, NH 2 CHNH 2 PbBr (3-o) I o, [CH 3 NH 3] (1-x) [NH 2 CHNH 2] x PbBr 3, [CH ₃ NH ₃ ] _(1-x) [NH ₂ CHNH ₂ ] _x PbBr _(3-o) I _o &Lt; / RTI &gt;

Where o is a real number greater than 0 and less than 3, x is a real number greater than 0 and less than 1, but is not so limited.

The electron blocking layer 120 may further include a polymer in addition to the first perovskite compound represented by Formula 1.

In addition, the hole blocking layer 140 may further include a second perovskite represented by Formula 2, as well as a polymer.

The polymer may be dissolved in a solvent together with the first perovskite compound or the second perovskite compound and may be a polar polymer that can be mixed and dissolved in a polar solvent, .

The content of the polar polymer in the electron blocking layer 120 may be 5 to 60 parts by weight based on 100 parts by weight of the first perovskite compound represented by the general formula (1). For example, 10 to 50 parts by weight. For example, 20 to 40 parts by weight. When the polar high molecular weight content in the electron blocking layer is within the above range, the adhesion with the electron blocking layer can be improved and the electron blocking ability can be further improved. Therefore, the dark current can be reduced and the photoelectric conversion efficiency can be maximized.

The content of the polar polymer in the hole blocking layer 140 may be 5 to 60 parts by weight based on 100 parts by weight of the second perovskite compound represented by the general formula (2). For example, 10 to 50 parts by weight. For example, 20 to 40 parts by weight. When the polar high molecular weight content in the hole blocking layer is within the above range, the adhesive strength to the hole blocking layer can be improved to further enhance the hole blocking ability. Therefore, the dark current can be reduced and the photoelectric conversion efficiency can be maximized.

The polar polymeric material may be selected from the group consisting of polyamic acid, polyimide, polyvinyl alcohol (PVA), polyacrylic acid, polyhydroxyethyl methacrylate (PHEMA), polymethylmethacrylate (PMMA), polyacrylate, polyacrylonitrile PAN), but are not limited thereto. In addition, the polymer material may include a copolymer of the above-mentioned materials.

The polymer may be mixed with the first perovskite compound or the second perovskite compound to further improve the adhesion of the electron blocking layer or the hole blocking layer and further improve the electron blocking ability or the hole blocking ability, And the photoelectric conversion efficiency can be maximized. For example, in an electron blocking layer or a hole blocking layer, the polymer may form a complex with perovskite. For example, in the electron blocking layer or the hole blocking layer, the polymer may exist in a separate phase to form a perovskite phase and a separated double layer from each other.

The solvent may comprise a variety of solvent materials. For example, the solvent may be selected from the group consisting of water, methanol, ethanol, acetone, benzene, toluene, hexane, acetonitrile, dimethylformamide (DMF), dimethylsulfoxide (DMSO) (NMP), methylene chloride (CH ₂ Cl ₂ ), chloroform (CH ₃ Cl), tetrahydrofuran (THF), and mixtures thereof.

In one embodiment, the electron blocking layer 120 may further include polyimide, which is a polar polymer together with CH ₃ NH ₃ PbI ₃ , but is not limited thereto. The CH ₃ NH ₃ PbI ₃ may be a polycrystal, and the like. For example, the electron blocking layer 120 may include, but is not limited to, a complex of CH ₃ NH ₃ PbI ₃ and polyimide. For example, the electron blocking layer 120 may include, but is not limited to, a separate bilayer of CH ₃ NH ₃ PbI ₃ and polyimide.

In one embodiment, the hole blocking layer 140 may further include polyimide, which is a polar polymer together with CH ₃ NH ₃ PbBr ₃ , but is not limited thereto. The CH ₃ NH ₃ PbBr ₃ may be polycrystalline, but is not limited thereto. For example, the hole blocking layer 140 may include a complex of CH ₃ NH ₃ PbBr ₃ and polyimide, but is not limited thereto. For example, the hole blocking layer 140 may include, but is not limited to, a separate double layer of CH ₃ NH ₃ PbBr ₃ and polyimide.

According to one embodiment, a variety of regular or irregular patterns may be formed on the surface of the hole blocking layer 140. Specifically, a quadrangular star shape, a butterfly shape, a starfish shape, a sawtooth shape, a clover shape, and the like may be formed, but are not limited thereto.

The electron blocking layer 120 may have a thickness of 1 nm to 10 mu m. For example, the electron blocking layer 120 may have a thickness of 10 nm to 10 mu m or 50 nm to 5000 nm, but is not limited thereto. When the thickness of the electron blocking layer 120 satisfies the above range, it is possible to provide a photoelectric conversion element in which the photoelectric conversion efficiency is maintained at a substantially similar level or not significantly reduced while sufficiently exhibiting the dark current reduction effect.

The electron blocking layer 120 may be formed as described below.

The hole blocking layer 140 may have a thickness of 1 nm to 10 占 퐉. For example, the hole blocking layer 140 may have a thickness of 10 nm to 10 占 퐉, or 50 nm to 5000 nm, but the present invention is not limited thereto. When the thickness of the hole blocking layer 140 is in the above range, it is possible to provide a photoelectric conversion element in which the photoelectric conversion efficiency is kept at a substantially similar level or not significantly reduced while sufficiently exhibiting the dark current reduction effect.

The hole blocking layer 140 may be formed as described below.

The photoelectric conversion layer 130 may include, but is not limited to, a semiconductor, such as amorphous Se, CdZnTe, GaAs, InP, Si, and any combination thereof as the photoactive material.

Alternatively, the photoelectric conversion layer 130 may include a third perovskite compound represented by Formula 3, which is a photoactive material, but is not limited thereto.

The method of forming the photoelectric conversion layer 130 is not particularly limited, and various methods such as a solution process such as a doctor blade coating, a deposition, and the like can be used.

FIGS. 2A and 2B are diagrams schematically showing energy levels of the photoactive material contained in the photoelectric conversion layer 130 and the first perovskite compound contained in the electron blocking layer 120. FIG.

Referring to Figures 2a and 2b, the lowest unoccupied molecular orbital (LUMO) level of the optically active substance (E _{_L C)} may be up to the first perovskite LUMO energy level (E _{C _ P1)} of the compound. If the external voltage applied to the photoelectric conversion element, and a hole and an electron injection occurs, there may be a problem that the dark current is increased occurs, when it satisfies E _{C _L} ≤ E _{C _ P1,} to block the transmission of the electronic dark current It is possible to provide a reduction effect.

Referring to Figure 2a, the highest occupied molecular orbital (HOMO) level (E _{V _L)} of the photoactive material of the first perovskite compound of the HOMO energy (E _{V _ P1)} but be equal to or lower, this limited It is not. Also, Referring to Figure 2b, the HOMO level _(V E _{_L)} of the optically active material, but may be higher than the first page lobe HOMO level of the sky agent compound _(V E _{_ P1),} but is not limited to such.

FIGS. 3A and 3B are diagrams schematically showing energy levels of a photoactive material contained in the photoelectric conversion layer 130 and a second perovskite compound contained in the hole blocking layer 140. FIG.

Referring to Figures 3a and 3b, the HOMO level of the optically active substance (E _{_L V)} may be more than the second page lobe HOMO level of the sky agent compound _{(V _} E _P2). If the external voltage applied to the photoelectric conversion element, and a hole and an electron injection occurs, there may be a problem that the dark current is increased occurs, when it satisfies E _{V _L} ≥ E _{V _ P2,} to block the passing of the hole dark current It is possible to provide a reduction effect.

Referring to FIG. 3A, the LUMO level (E _{C _L} ) of the photoactive material may be equal to or higher than the LUMO level (E _{c _ P2} ) of the second perovskite compound, but is not limited thereto. Also, referring to FIG. 3B, the LUMO level (E _{C _L} ) of the photoactive material may be lower than the LUMO level (E _{c _ P2} ) of the second perovskite compound, but is not limited thereto.

The photoelectric conversion layer 130 may include a third perovskite compound represented by the following Formula 3:

(3)

[A ³ ] [B ³ ] [X ³ _(3-k) Y ³ _k ]

In Formula 3,

A ³ is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,

B ³ is at least one divalent inorganic-cation,

X ³ and Y ³ are, independently of each other, at least one monovalent anion,

k is a real number satisfying 0? k? 3.

The third perovskite compound may be a polycrystalline. The term " polycrystal " means a form in which crystals are bonded to each other. That is, the crystals of the third perovskite compound may be bonded to each other, but the present invention is not limited thereto. The cross section of the photoelectric conversion layer 130 may have a shape as shown in FIG. 12, but is not limited thereto. If the third perovskite compound is polycrystalline, it is possible to provide a dark current reduction effect and provide an effect of improving photoelectric conversion efficiency.

The length of the longest axis in one crystal of the third perovskite compound may be from 1 mu m to 300 mu m. For example, the length of the longest axis in one crystal of the third perovskite compound may be 10 탆 to 50 탆, but is not limited thereto. When the length of the longest axis of the crystal of the third perovskite compound satisfies the above range, it is possible to provide a photoelectric conversion element in which the photoelectric conversion efficiency is not reduced while sufficiently exhibiting the dark current reduction effect.

In the above formula (3), a detailed description of A ³ is described with reference to A ¹ in formula (1).

In the above formula (3), a detailed description of B ³ is the same as the description of B ¹ in the formula (1).

In the above formula (3), a detailed description of X ³ is given with reference to X ¹ in the formula (1).

In the above formula (3), a detailed description of Y ³ is the same as the description of Y ¹ in the formula (1).

For a detailed description of k in Formula 3, see the description of n in Formula 1.

In one embodiment, the third perovskite compound represented by Formula 3 may be CH ₃ NH ₃ PbI ₃ , but is not limited thereto.

The photoelectric conversion layer 130 can absorb light, and can absorb, for example, infrared rays, visible rays, or X-rays. More specifically, the photoelectric conversion layer 130 can absorb x-rays.

In general, a solar cell, an infrared imaging device and a visible light imaging device using a perovskite compound may be formed to have a thickness of 1 mm or less by using a deposition method such as spin coating to form a photoelectric conversion layer. However, it is difficult to form a perovskite photoelectric conversion layer having a thickness of several hundreds of micrometers or more for a large area applied to an X-ray imaging apparatus.

In order to solve the above problems, in the present invention, a doctor blade coating using a solution-based process was performed, thereby forming a polycrystalline perovskite film having a thickness of several hundreds of micrometers or more.

The photoelectric conversion layer 130 according to the present invention may have a thickness of 0.1 to 1500 μm. When the thickness of the photoelectric conversion layer 130 satisfies the above range, the photoelectric conversion efficiency of light having a short wavelength such as an X-ray as well as infrared rays and visible light can be improved.

In one embodiment, when the light is visible light or infrared, the photoelectric conversion layer 130 may have a thickness of 0.1 to 1 占 퐉, but the present invention is not limited thereto.

In another embodiment, when the light is an x-ray, the photoelectric conversion layer 130 may have a thickness of 300 mu m to 1500 mu m, but is not limited thereto.

The first conductive layer 110 and the second conductive layer 150 may be reflective, transmissive or semi-transmissive depending on the purpose.

The first conductive layer 110 and the second conductive layer 150 may comprise a conductive material such as a metal, a metal oxide, an electrically conductive organic compound, or a combination thereof. In order to form the first conductive layer 110, the material for the first conductive layer may be indium tin oxide (ITO), indium zinc oxide (IZO), tin oxide (SnO ₂ ), zinc oxide (ZnO) , But is not limited thereto. Alternatively, the material for the first conductive layer may be selected from the group consisting of gold (Au), silver (Ag), chromium (Cr), nickel (Ni), and any combination thereof in order to form the transflective or reflective first conductive layer But is not limited thereto. The material for the second conductive layer refers to the description for the material for the first conductive layer.

In one embodiment, if the light is an x-ray, the second conductive layer 150 may be reflective, transmissive, or semi-transmissive.

In other implementations, the second conductive layer 150 may be transmissive if the light is infrared or visible. Since light is incident on the side of the second conductive layer 150, the second conductive layer 150 should be sufficiently transparent.

The thicknesses of the first conductive layer 110 and the second conductive layer 150 are not particularly limited, but may have a thickness of 10 nm to 2000 nm.

The method of forming the first conductive layer 110 and the second conductive layer 150 is not particularly limited, and various methods such as coating and deposition may be used.

4 is a diagram schematically showing a method of driving a photoelectric conversion element according to an embodiment. Fig. 4 shows a planar imaging device as an example, and various other modifications are possible.

A first conductive layer 411, 412, 413; A second conductive layer 450; And an electron blocking layer 420, a photoelectric conversion layer 430 and a hole blocking layer 440 interposed between the first and second conductive layers 411, 412 and 413 and the second conductive layer 450;

The electron blocking layer 420 is interposed between the first conductive layers 411, 412, and 413 and the photoelectric conversion layer 430;

A hole blocking layer 440 is interposed between the second conductive layer 450 and the photoelectric conversion layer 430;

The electron blocking layer 420 may include a first perovskite compound represented by Formula 1,

The hole blocking layer 440 may include a second perovskite compound represented by Formula 2,

An electric field can be applied with the first conductive layers 411, 412 and 413 as a negative bias and the second conductive layer 450 as a positive bias.

The first conductive layers 411, 412, and 413, the second conductive layer 450, the electron blocking layer 420, the photoelectric conversion layer 430, and the hole blocking layer 440, 1, the description of the first conductive layer 110, the second conductive layer 150, the electron blocking layer 120, the photoelectric conversion layer 130, and the hole blocking layer 140 will be described.

A power source 470 is connected to the second conductive layer 450 to apply an electric field. The other end of the power source 470 may be grounded. Accordingly, an electric field is applied between the first conductive layers 411, 412, and 413 and the second conductive layer 450. When the light 480 is incident on the photoelectric conversion layer 430, it is converted into electrons and holes by the photoactive material contained in the photoelectric conversion layer 430. The converted electrons and holes are attracted to the second conductive layer 450 and the first conductive layers 411, 412, and 413, respectively, by an electric field.

The first conductive layers 411, 412, and 413 may be connected to the detectors 461, 462, and 463. The first conductive layers 411, 412, and 413 may be interposed between the detecting portions 461, 462, and 463 and the electron blocking layer 420. That is, the detecting portions 461, 462, and 463 may be disposed on the back surface (that is, the light output surface) of the photoelectric conversion layer 430.

The detectors 461, 462, and 463 detect the charge 490 generated in the photoelectric conversion layer 430. The detection units 461, 462 and 463 include the readout circuits 461b, 462b and 463b for reading the charges 490 collected in the storage capacitors 461a, 462a and 463a and the storage capacitors 461a, 462a and 463a can do.

The readout circuits 461b, 462b, and 463b convert the charge amounts of the storage capacitors 461a, 462a, and 463a into digital signals. Such a digital signal is converted into a video signal by the signal processing unit.

The second conductive layer 450, the electron blocking layer 420, the photoelectric conversion layer 430, and the hole blocking layer 440 may be formed to cover the first conductive layers 411, 412, and 413.

5 is a cross-sectional view schematically showing a method of manufacturing a photoelectric conversion element according to an embodiment.

A method of manufacturing a photoelectric conversion device according to an exemplary embodiment includes: providing a first conductive layer; Providing a first mixture comprising an A ¹ -containing precursor, a B ¹ -containing precursor and a solvent on the first conductive layer to form an electron blocking layer comprising a first perovskite compound represented by Formula 1 ; Forming a photoelectric conversion layer on the electron blocking layer; Providing a second mixture comprising an A ² -containing precursor, a B ² -containing precursor and a solvent on the photoelectric conversion layer to form a hole blocking layer comprising a second perovskite compound represented by Formula 2 ; And providing a second conductive layer on the hole blocking layer.

First, as shown in FIG. 5, a first conductive layer 510 is provided. The first conductive layer 510 is as described in FIG. 1, and the first conductive layer 510 may be provided by applying various known methods, so a detailed description thereof will be omitted.

Next, an electron blocking layer 520 is formed on the first conductive layer 510. The electron blocking layer 520 includes the first perovskite compound represented by the above formula (1). The first perovskite compound represented by Formula 1 may be formed by providing a first mixture comprising an A ¹ -containing precursor, a B ¹ -containing precursor, and a solvent.

In addition, the electron blocking layer 520 may further include a polymer together with the first perovskite compound. Thus, the first mixture may further comprise the polymer or precursor thereof.

The polymer may include various high molecular materials, and may be a polar polymer that can be dissolved in a solvent and mixed with the first perovskite compound. For example, the polar polymer material may be selected from the group consisting of polyamic acid, polyimide, polyvinyl alcohol (PVA), polyacrylic acid, polyhydroxyethyl methacrylate (PHEMA), polymethylmethacrylate (PMMA) Acrylonitrile (PAN), and the like, but is not limited thereto. In addition, the polymer material may include a copolymer of the above-mentioned materials.

For example, the first mixture may be spin coated on the first conductive layer 510. If the first mixture is to be provided by spin coating, the spin coating conditions can be adjusted, for example, by controlling the composition of the first mixture and the composition of the first mixture at a coating rate of about 2000 rpm to about 4000 rpm and a temperature range of about 80 & May be selected in consideration of the structure of the electron blocking layer 520.

Meanwhile, the first mixture may be provided on the first conductive layer 510 by applying various other known methods.

The first mixture provided on the first conductive layer 510 may be heat treated to form the electron blocking layer 520. The heat treatment temperature may be within a temperature range of about 100 ° C to 300 ° C. If the heat treatment temperature is less than 100 ° C, the adhesion of the electron blocking layer may be decreased, and if it is higher than 300 ° C, the first perovskite may be damaged.

For example, the heat treatment conditions can be selected in consideration of the composition of the first mixture and the structure of the electron blocking layer 520 within a time range of 15 minutes to 2 hours and a temperature range of 100 占 폚 to 300 占 폚.

The electron blocking layer 520 thus formed may include a first perovskite. For example, the first perovskite and the polar polymer may be included. For example, it may comprise a complex of the first perovskite and the polar polymer. For example, it may comprise a separate two-layered layer of the first perovskite and the polar polymer.

The A ¹ - and B ¹ containing precursors - containing precursor of the description of A ¹ and B ^1, please refer to the description of the A ¹ and B ¹ of the description of each of the above formula (1).

For example, the A ¹ -containing precursor is selected from a halide of A ¹ (e.g., (A ¹ ) (X ¹ )) and the B ¹ -containing precursor is a halide of B ¹ , (B ¹ ) (Y ¹ ) ₂ ). The descriptions of A ¹ , B ¹ , X ¹ and Y ¹ in the above (A ¹ ) (X ¹ ) and (B ¹ ) (Y ¹ ) ₂ refer to the description of Formula 1 in the present specification, respectively.

The solvent may be selected from materials having high solubility of the A ¹ -containing precursor and the B ¹ -containing precursor. For example, the solvent may be dimethylformamide, dimethylsulfoxide, gamma -butyrolactone, N-methyl-2-pyrrolidone, or a combination thereof, but is not limited thereto.

A photoelectric conversion layer 530 is then provided on the electron blocking layer 520. The photoelectric conversion layer 530 includes a third perovskite compound represented by Formula 3 below. The third perovskite compound represented by Formula 3 may be formed by adding a non-solvent to a mixture containing an A ³ -containing precursor, a B ³ -containing precursor, and a solvent to provide a third mixture.

The solvent may be selected from materials having high solubility of the A ³ -containing precursor and the B ³ -containing precursor. For example, the solvent may be dimethylformamide, dimethylsulfoxide, gamma -butyrolactone, or a combination thereof, but is not limited thereto.

The non-solvent can be selected from materials having low solubility of the A ³ -containing precursor and the B ³ -containing precursor. For example, the non-solvent may include at least one selected from the group consisting of alpha-terpineol, hexyl carbitol, butyl carbitol acetate, hexyl cellosolve, butyl cellosolve, acetate, and the like, but the present invention is not limited thereto.

For example, the third mixture may be doctor blade or bar coated on the electron blocking layer 520. By adding a non-solvent, the viscosity of the third mixture can be increased, so that the third mixture can be provided by doctor blade or bar coating. When the third blend is provided by doctor blade coating, the doctor blade coating conditions are, for example, within a temperature range of about 80 占 폚 to 200 占 폚, and the composition of the third mixture and the composition of the photoelectric conversion layer 530 Can be selected in consideration of the structure.

 Meanwhile, the third mixture may be provided on the electron blocking layer 520 using various other known methods.

The third mixture provided on the electron blocking layer 520 may be heat-treated to form the photoelectric conversion layer 530.

For example, the heat treatment conditions may be selected in consideration of the composition of the third mixture and the structure of the photoelectric conversion layer 530 within a time range of 15 minutes to 2 hours and a temperature range of 100 占 폚 to 200 占 폚.

Alternatively, the third mixture may be provided on the electron blocking layer 520 to provide a preliminary photoelectric conversion layer comprising the third perovskite compound represented by Formula 3, It is possible to provide a photoelectric conversion layer by pressing at a high pressure (for example, an air pressure range of 5 atm to 10 atm) at a high temperature (for example, a temperature range of 100 to 200 占 폚). At this time, the A ³ -containing precursor may be further supplied in a gas phase. In this case, the third perovskite compound represented by Formula 3 may be a polycrystalline.

Next, a hole blocking layer 540 is provided on the photoelectric conversion layer 530. The hole blocking layer 540 includes a second perovskite compound represented by the above formula (2). The second perovskite compound represented by Formula 2 may be formed by providing a second mixture containing an A ² -containing precursor, a B ² -containing precursor, and a solvent.

In addition, the hole blocking layer 540 may further include a polymer together with the second perovskite compound. Thus, the second mixture may further comprise the polymer or precursor thereof.

The polymer may include various high molecular materials and may be a polar polymer that can be mixed with a solvent together with the second perovskite compound. For example, the polar polymer material may be selected from the group consisting of polyamic acid, polyimide, polyvinyl alcohol (PVA), polyacrylic acid, polyhydroxyethyl methacrylate (PHEMA), polymethylmethacrylate (PMMA) Acrylonitrile (PAN), and the like, but is not limited thereto. In addition, the polymer material may include a copolymer of the above-mentioned materials.

For example, the second mixture may be spin-coated on the photoelectric conversion layer 530. If the second mixture is provided by spin coating, the spin coating conditions can be adjusted, for example, at a coating rate of from about 2000 rpm to about 4000 rpm and a temperature range of from about 80 [deg.] C to about 200 & May be selected in consideration of the structure of the hole blocking layer 540.

Meanwhile, the second mixture may be provided on the photoelectric conversion layer 530 by applying various other known methods.

The second mixture provided on the photoelectric conversion layer 530 may be heat-treated to form the hole blocking layer 540. The heat treatment temperature may be within a temperature range of about 100 ° C to 300 ° C. If the heat treatment temperature is less than 100 ° C, the adhesive strength of the electron blocking layer may decrease, and if it is higher than 300 ° C, the second perovskite may be damaged.

For example, the heat treatment conditions may be selected in consideration of the composition of the second mixture and the structure of the hole blocking layer 540 within a time range of 15 minutes to 2 hours and a temperature range of 100 占 폚 to 300 占 폚.

The hole blocking layer 540 thus formed may include a second perovskite. For example, a second perovskite and the polar polymer. For example, it may include a complex of the second perovskite and the polar polymer. For example, it may comprise a separate second layer of the second perovskite and the polar polymer.

Wherein A ² - B ² containing precursor and - a description of the containing precursor A ² and B ² of, see the description of the A ² and B ² of the description of each of the above formula (2).

For example, the A ² -containing precursor is selected from a halide of A ² (e.g., (A ² ) (X ² )) and the B ² -containing precursor is a halide of B ² , (B ² ) (Y ² ) ₂ ). The descriptions of A ² , B ² , X ² and Y ² in the above (A ² ) (X ² ) and (B ² ) (Y ² ) ₂ refer to the description of Formula 1 in the present specification, respectively.

The solvent may be selected from materials having high solubility of the A ² -containing precursor and the B ² -containing precursor. For example, the solvent may be dimethylformamide, dimethylsulfoxide, gamma -butyrolactone, N-methyl-2-pyrrolidone, or a combination thereof, but is not limited thereto.

A second conductive layer 550 is then provided on the hole blocking layer 540. The second conductive layer 550 is as described with reference to FIG. 1, and the second conductive layer 550 may be provided by applying various known methods, so a detailed description will be omitted.

The photoelectric conversion element according to one embodiment may be included in the imaging device. The imaging device may be stationary or mobile.

The imaging apparatus may include a light irradiation unit, a light detection unit, and a control unit.

The light irradiating unit may include a light source for generating light and a collimator for guiding the path of the generated light to adjust an irradiation area of the light.

The light source may include, for example, an X-ray tube. The x-ray tube may be implemented as a bipolar tube of positive and negative electrodes. The voltage applied between the cathode and the anode of the X-ray tube is called the tube voltage, and its size can be expressed as the peak value kVp. As the tube voltage increases, the speed of the thermoelectrons increases and consequently the energy (photon energy) of the x-ray generated by collision with the target material increases. The current flowing through the X-ray tube is referred to as a tube current and can be expressed as an average value mA. As the tube current increases, the number of thermoelectrons emitted from the filament increases. As a result, the dose of the X- do. Therefore, the energy of the X-ray can be controlled by the tube voltage, and the intensity or dose of the X-ray can be controlled by the tube current and the X-ray exposure time.

The photodetecting unit detects the light irradiated from the light irradiating unit and transmitted through the object, and may include, for example, a plate-type photodetector. The photodetector may include the photoelectric conversion element 100 described with reference to Fig.

The control unit includes a voltage generating unit, a signal processing unit, and an operation unit, and can control the overall operation of the image sensing apparatus.

The voltage generating unit generates a high voltage for generating light and applies a voltage to the light source in the light irradiating unit.

The signal processing unit processes the information detected by the optical detecting unit to generate an image, or generates a control signal based on information input to the operation unit to control various components of the image sensing apparatus.

The operation unit provides an interface for the operation of the image capturing apparatus, and can receive a command for operating the image capturing apparatus and various information related to the image capturing from the user.

The image pickup apparatus may further include an output section. The output unit may display image-related information such as light irradiation, or may display an image generated by the signal processing unit.

Hereinafter, the photoelectric conversion element according to one embodiment will be described in more detail by way of examples, but the present invention is not limited to the following synthesis examples and examples. In the following Synthesis Examples, the amounts of 'B' and 'A' used in the expression "B" was used in place of "A" were the same on the molar equivalent basis.

[ Example ]

Manufacturing example  1. Preparation of Electron Barrier Material (Mixture B)

(1) Preparation of mixture A

P-phenylenediamine and biphenyl-tetracarboxylic dianhydride were mixed in a molar ratio of 1: 0.975 to the reaction vessel, N-methyl-2-pyrrolidone (NMP) was added to the mixture, The mixture was stirred at room temperature for 5 hours. Then, the mixture A was prepared by reacting the mixture in a sealed reaction vessel at 40 캜 for 12 hours.

(2) Preparation of mixture B

To the mixture CH ₃ A 4.8g 1.59g NH ₃ I, PbI ₂ And 2.4 g of dimethylformamide were added, and then the mixture was stirred at room temperature overnight.

Manufacturing example  2. Preparation of hole blocking materials (mixture C, mixture D or mixture E)

2-1. Preparation of mixture C

Mixture C was prepared by mixing CH ₃ NH ₃ Br, PbBr ₂ , dimethylformamide and dimethylsulfoxide in a molar ratio of 1: 1: 6.7: 2 to the reaction vessel, followed by stirring at room temperature for 1 hour.

2-2. Preparation of mixture D

(1) Preparation of mixture A

P-phenylenediamine and biphenyl-tetracarboxylic dianhydride were mixed in a molar ratio of 1: 0.975 to the reaction vessel, N-methyl-2-pyrrolidone (NMP) was added to the mixture, The mixture was stirred at room temperature for 5 hours. Then, the mixture A was prepared by reacting the mixture in a sealed reaction vessel at 40 캜 for 12 hours.

(2) Preparation of mixture D

To the mixture CH ₃ A 9.6g NH ₃ Br 2.34g, PbBr ₂ And 4.8 g of dimethylformamide, and then stirred overnight at room temperature to prepare a mixture D.

2-3. Preparation of mixture E

In Preparation Example 2-2, a mixture E was prepared in the same manner as in Preparation Example 2-2, except that 1.17 g of CH ₃ NH ₃ Br was used instead of 2.34 g and 3.835 g of PbBr ₂ was used instead of 7.67 g.

Manufacturing example  3. Photoelectricity  Preparation of conversion material (mixture F or mixture G)

3-1. Preparation of mixture F

Mixture F was prepared by adding CH ₃ NH ₃ I, PbI ₂ , dimethylformamide and dimethylsulfoxide in a molar ratio of 1: 1: 6.7: 2 to the reaction vessel, followed by stirring for 1 hour.

3-2. Preparation of mixture G

Mixing the lactone in a reaction vessel with 7.75g 18.44g PbI ₂ and γ- butynyl, and the mixture was stirred and then stirred for 1 hour at 80 ℃, in further addition of NH ₃ CH ₃ I, and 6.36g, 90 ~ 100 ℃ for 4 hours Lt; / RTI &gt; Then, 4 g of alpha -terpinol was further added to the mixture, and the mixture G was prepared by stirring at 90 to 100 DEG C for 4 hours.

Example  One. Photoelectricity  Fabrication of conversion device

Amorphous ITO was sputtered onto a glass substrate to form a first conductive layer with a thickness of 200 nm.

The mixture B was spin-coated on the first conductive layer at 2000 rpm for 30 seconds and then dried at 120 캜 for 30 minutes to form an electron blocking layer having a thickness of 3 탆.

The mixture G was coated on the electron blocking layer with a doctor blade, heat-treated at 120 ° C for 1 hour, and further heat-treated in a vacuum oven at 90 ° C for 1 hour to form a preliminary photoelectric conversion layer. The preliminary photoelectric conversion layer was pressed at 120 占 폚 and 5 atmospheric pressure to form a photoelectric conversion layer having a thickness of 830 占 퐉.

The mixture C was spin-coated on the photoelectric conversion layer at 2000 rpm for 30 seconds. At this time, diethyl ether was added dropwise at a rate of 2 ml per second for 20 seconds from the point of 10 seconds after the spin coating. This was heat-treated at 100 DEG C for 10 minutes to form a hole blocking layer having a thickness of 1 mu m.

A glass substrate sputtered with a thickness of 200 nm of amorphous ITO was coupled to the hole blocking layer to form a second conductive layer, thereby fabricating a photoelectric conversion element.

Figs. 6A to 6C show photographs of the surface of the electron blocking layer, the photoelectric conversion layer and the hole blocking layer according to Example 1. Fig.

SEM images of the electron blocking layer, the photoelectric conversion layer and the hole blocking layer in the photoelectric conversion element of Example 1 are shown in Figs. 11, 12 and 13, respectively.

Example  2. Photoelectricity  Fabrication of conversion device

A photoelectric conversion element was manufactured in the same manner as in Example 1 except that the mixture D was used instead of the mixture C in forming the hole blocking layer.

An SEM image of the hole blocking layer in the photoelectric conversion element of Example 2 is shown in Fig.

Referring to FIG. 14, it can be seen that a square-shaped pattern is formed on the surface of the hole blocking layer.

Example  3. Photoelectricity  Fabrication of conversion device

A photoelectric conversion device was fabricated in the same manner as in Example 1 except that the mixture E was used instead of the mixture C in forming the hole blocking layer.

Comparative Example  One. Photoelectricity  Fabrication of conversion device

A photoelectric conversion element was fabricated in the same manner as in Example 1 except that the hole blocking layer and the electron blocking layer were not included.

Comparative Example  2. Photoelectricity  Fabrication of conversion device

TiO ₂ was used instead of the mixture C in the formation of the hole blocking layer and Spiro-OMeTAD (2,2 ', 7,7'-tetrakis (N, N-dimethoxyphenyl-amine) 9 , 9'-spiro-bifluorene) was used as a photoelectric conversion element.

Comparative Example  3. Photoelectricity  Fabrication of conversion device

A photoelectric conversion element was fabricated in the same manner as in Example 1 except that the mixture A was used instead of the mixture B in forming the electron blocking layer.

Comparative Example  4. Photoelectricity  Fabrication of conversion device

A photoelectric conversion element was prepared in the same manner as in Example 1, except that the mixture A was used in place of the mixture B in forming the electron blocking layer and that the mixture A was dried at 200 ° C instead of 120 ° C.

Comparative Example  5. Photoelectricity  Fabrication of conversion device

Except that the hole blocking layer and the electron blocking layer were not included and the mixture F was spin-coated instead of the doctor blade coating in the formation of the photoelectric conversion layer to form a photoelectric conversion layer with a thickness of 0.5 mu m. A photoelectric conversion element was fabricated in the same manner as in Example 1.

Evaluation example  One

Various voltages were applied to the photoelectric conversion elements of Examples 1 to 3 and Comparative Examples 1 and 2, and the current density was measured. At this time, the experiment was repeated by setting the condition (White) and the condition (White). The results of this experiment are shown in Fig.

Referring to FIG. 7, it can be seen that the photoelectric conversion elements of Examples 1 to 3 have a lower dark current.

Evaluation example  2

Various voltages were applied to the photoelectric conversion elements of Comparative Examples 3 and 4, and the current density was measured accordingly. At this time, the experiment was repeated by setting the condition (White) and the condition (White). The results of this experiment are shown in Fig.

Referring to FIG. 8, in the case of the photoelectric conversion devices of Comparative Examples 3 and 4, it can be seen that both photocurrent and dark current were greatly reduced by using only polyimide as the electron blocking layer. Particularly, in the case of Comparative Example 4, it can be confirmed that the photocurrent as well as the dark current decreased with the progress of the imidization. This result shows that when A is used instead of the mixture B in the formation of the electron blocking layer, the generated polyimide acts as a barrier for the photogenerated charge to move to the electrode.

Evaluation example  3

Various voltages were applied to the photoelectric conversion element of Example 2, and the currents corresponding thereto were measured.

The distance between the X-ray source and the photoelectric conversion element was 30 cm, the tube voltage of the X-ray was 100 kvp, the tube current of the X-ray was 20 mA, and the irradiation time of the X-ray was 0.2 seconds .

The results of this experiment are shown in Fig.

Referring to FIG. 9, it is confirmed that the photoelectric conversion element of Example 2 has excellent sensitivity to X-rays.

Evaluation example  4

(A) and (b) photoluminescence intensity of the photoelectric conversion layer of Comparative Example 1 and Comparative Example 5 were measured, and the results are shown in Figs. 10 (a) and 10 ). At this time, a light source of 505 nm wavelength was used as an excitation source, and a carrier lifetime τ was measured using time-resolved photoluminescence.

10 (a), the photoelectric conversion layer of Comparative Example 5 showed an absorption edge at about 760 nm, while the photoelectric conversion layer of Comparative Example 1 showed an absorption band extending around 840 nm absorption band. In addition, Comparative Example 1 exhibited about 100 times stronger photoluminescence than Comparative Example 5.

10 (b), the photoelectric conversion layer of Comparative Example 5 showed a carrier lifetime (tau) value of about 128 ns, while the photoelectric conversion layer of Comparative Example 1 had a carrier lifetime of about 1,052 ns (tau) values.

From this result, it can be seen that when the mixture G is doctor blade coated to form a photoelectric conversion layer having a thickness of several hundreds of micrometers or more, rather than forming a photoelectric conversion layer having a thickness of several micrometers by spin coating the mixture F upon formation of the photoelectric conversion layer , It can be seen that the photoelectric conversion efficiency can be further improved.

100: Photoelectric conversion element
110, 411, 412, 413, 510: a first conductive layer
120, 420, 520: electron blocking layer
130, 430, 530: photoelectric conversion layer
140, 440, 540: hole blocking layer
150, 450, 550: second conductive layer
461, 462, 463:
461b, 462b, 463b:
461a, 462a, 463a: storage capacitor
470: Power supply
480: Light
490: charge

Claims (25)

A first conductive layer; A second conductive layer; A photoelectric conversion layer interposed between the first conductive layer and the second conductive layer; An electron blocking layer interposed between the photoelectric conversion layer and the first conductive layer; And a hole blocking layer interposed between the photoelectric conversion layer and the second conductive layer,
Wherein the electron blocking layer comprises a first perovskite compound represented by the following formula (1)
Wherein the hole blocking layer comprises a second perovskite compound represented by Formula 2:
&Lt; Formula 1 >
[A ¹ ] [B ¹ ] [X ¹ _(3-n) Y ¹ _n ]
In Formula 1,
A ¹ is at least one monovalent organic-cation, monovalent inorganic-cation or any combination thereof,
B ¹ is at least one divalent inorganic-cation,
X ¹ and Y ¹ are, independently of each other, at least one monovalent anion,
n is a real number satisfying 0? n? 3,
(2)
[A ² ] [B ² ] [X ² _(3-m) Y ² _m ]
In Formula 2,
A ² is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,
B ² is at least one divalent inorganic-cation,
X ² and Y ² are, independently of each other, at least one monovalent anion,
m is a real number satisfying 0? m? 3. The method according to claim 1,
(R ₁ R ₂ R ₃ R ₄ N) ⁺ , (R ₁ R ₂ R ₃ R ₄ P) ⁺ , (R ₁ R ₂ R ₃ R ₄ As) ⁺ , (R ₁ R _{2 ^{R 3 R 4 Sb) +,}} (R 1 R 2 N = C (R 3) -NR 4 R 5) +, substituted or unsubstituted cycloheptyl tart Rie ^{iodonium, Li +, Na +, K} +, Rb + , Cs ⁺ , Fr ^+, or any combination thereof;
Wherein R ₁ to R ₅ and the substituted cycloheptyl at least one of the substituents of the tart Rie titanium represent, independently of each other, hydrogen, heavy hydrogen, -F, -Cl, -Br, -I, hydroxyl group, C ₁ -C ₂₀ An alkyl group, a C ₂ -C ₁₀ alkenyl group, a C ₂ -C ₁₀ alkynyl group, a C ₁ -C ₂₀ alkoxy group and -N (Q ₁ ) (Q ₂ )
Wherein Q ₁ and Q ₂ are each independently selected from the group consisting of hydrogen, deuterium, C ₁ -C ₂₀ alkyl groups, C ₂ -C ₁₀ alkenyl groups, C ₂ -C ₁₀ alkynyl groups and C ₁ -C ₂₀ alkoxy groups, Conversion element. The method according to claim 1,
A ¹ and A ² are each independently ^{_{(CH 3 NH 3) +,}} ((CH 3 CH 2 CH 2 CH 2) NH 3) +, (NH 2 CHNH 2) +, K +, Rb +, Cs + and Wherein the photoelectric conversion element is selected from any combination thereof. The method according to claim 1,
B ¹ and B ² are independently each other, La ^{2 +,} Ce ^{+ 2,} Pr ^{+ 2,} Nd ^{+ 2,} Pm ^{+ 2,} Sm ^{+ 2,} Eu ^{+ 2,} Gd ^{+ 2,} Tb ^2+, Dy ^{+ 2,} Ho ^{2 +, Er 2 +, Tm} 2 +, Yb 2 +, Lu 2 +, Be 2 +, Mg 2 +, Ca 2 +, Sr 2 +, Ba 2 +, Ra 2 +, Pb 2 +, Sn 2 + Or any combination thereof. The method according to claim 1,
B ¹ and B ² are independently of each other, Pb ^{2 +,} the photoelectric conversion element. The method according to claim 1,
X ¹ , Y ¹ , X ² and Y ² are independently selected from Cl ^- , Br ^- and I ^- . The method according to claim 1,
The first perovskite compound represented by Formula 1 and the second perovskite compound represented by Formula 2 are independently selected from the group consisting of CH ₃ NH ₃ PbI ₃ , CH ₃ NH ₃ PbBr ₃ , CH ₃ NH ₃ PbCl _{3, CH 3 NH 3 PbBr (} 3-o) I o, CH 3 NH 3 PbCl (3-o) Br o, CH 3 NH 3 PbCl (3-o) I o, CsPbI 3, CsPbBr 3, CH 3 CH _{2 CH 2 CH 2 NH 3 PbBr} 3, NH 2 CHNH 2 PbBr 3, NH 2 CHNH 2 PbBr (3-o) I o, [CH 3 NH 3] (1-x) [NH 2 CHNH 2] x PbBr 3 And [CH ₃ NH ₃ ] _(1-x) [NH ₂ CHNH ₂ ] _x PbBr _(3-o) I _o , Where o is a real number greater than 0 and less than 3, and x is a real number greater than 0 and less than 1. The method according to claim 1,
Wherein the electron blocking layer and the hole blocking layer further include a polar polymer independently from each other. The method of claim 8, wherein
The content of the polar polymer in the electron blocking layer is 5 to 60 parts by weight based on 100 parts by weight of the first perovskite compound represented by the general formula (1)
Wherein the content of the polar polymer in the hole blocking layer is 5 to 60 parts by weight based on 100 parts by weight of the second perovskite compound represented by the general formula (2). 9. The method of claim 8,
The polar polymer may be selected from the group consisting of polyamic acid, polyimide, polyvinyl alcohol (PVA), polyacrylic acid, polyhydroxyethyl methacrylate (PHEMA), polymethyl methacrylate (PMMA), polyacrylate, polyacrylonitrile ), And any combination thereof. The method according to claim 1,
The electron blocking layer comprises a CH ₃ NH ₃ PbI ₃ as polyimide,
Wherein the hole blocking layer comprises CH ₃ NH ₃ PbBr ₃ and a polyimide. The method of claim 11, wherein
Wherein the hole blocking layer has a rectangular shape, a butterfly shape, a starfish shape, a sawtooth shape, or a clover shape on the surface of the hole blocking layer. The method according to claim 1,
Wherein the photoelectric conversion layer comprises a photoactive material;
The lowest unoccupied molecular orbital (LUMO) level of the photoactive substance is lower than the LUMO level of the first perovskite compound,
Wherein the highest occupied molecular orbital (HOMO) level of the photoactive material is not less than the HOMO level of the second perovskite compound. The method according to claim 1,
Wherein the photoelectric conversion layer comprises a third perovskite compound represented by Formula 3,
Wherein the third perovskite compound is a polycrystalline photoelectric conversion element:
(3)
[A ³ ] [B ³ ] [X ³ _(3-k) Y ³ _k ]
In Formula 3,
A ³ is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,
B ³ is at least one divalent inorganic-cation,
X ³ and Y ³ are, independently of each other, at least one monovalent anion,
k is a real number satisfying 0? k? 3. 15. The method of claim 14,
Wherein the third perovskite compound represented by Formula 3 is a form in which crystals are bonded to each other. 15. The method of claim 14,
And the length of the longest axis of the third perovskite compound represented by Formula 3 is 1 to 300 m. 15. The method of claim 14,
Wherein the third perovskite compound represented by Formula 3 is CH ₃ NH ₃ PbI ₃ . The method according to claim 1,
Wherein the photoelectric conversion layer absorbs infrared rays, visible rays, or x-rays. The method according to claim 1,
Wherein the photoelectric conversion layer has a thickness of 0.1 to 1500 mu m. The method according to claim 1,
Wherein the second conductive layer is a reflective, transmissive or semi-transmissive type photoelectric conversion element. Forming an electron blocking layer comprising a first perovskite compound represented by the following Formula 1 on the first conductive layer;
Forming a photoelectric conversion layer on the electron blocking layer;
Forming a hole blocking layer including a second perovskite compound represented by Formula 2 on the photoelectric conversion layer; And
And forming a second conductive layer on the hole blocking layer. A method for manufacturing a photoelectric conversion element,
&Lt; Formula 1 >
[A ¹ ] [B ¹ ] [X ¹ _(3-n) Y ¹ _n ]
In Formula 1,
A ¹ is at least one monovalent organic-cation, monovalent inorganic-cation or any combination thereof,
B ¹ is at least one divalent inorganic-cation,
X ¹ and Y ¹ are, independently of each other, at least one monovalent anion,
n is a real number satisfying 0? n? 3,
(2)
[A ² ] [B ² ] [X ² _(3-m) Y ² _m ]
In Formula 2,
A ² is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,
B ² is at least one divalent inorganic-cation,
X ² and Y ² are, independently of each other, at least one monovalent anion,
m is a real number satisfying 0? m? 3. 22. The method of claim 21,
Wherein the electron blocking layer and the hole blocking layer further include a polar polymer independently of each other. 22. The method of claim 21,
The forming of the electron blocking layer may include spin coating a first perovskite compound represented by Formula 1 and a polar polymer or a precursor thereof on the first conductive layer by spin coating, Gt; to &lt; / RTI &gt; 22. The method of claim 21,
The step of forming the photoelectric conversion layer
(a) adding a non-solvent to a mixture comprising an A ³ -containing precursor, a B ³ -containing precursor and a solvent, followed by stirring at a temperature of from 70 ° C to 120 ° C to obtain a third perovskite Preparing a compound solution; And
(b) coating the third perovskite compound solution on the electron blocking layer with a doctor blade or a bar.
(3)
[A ³ ] [B ³ ] [X ³ _(3-k) Y ³ _k ]
here,
A ³ is at least one monovalent organic-cation, a monovalent inorganic-cation or any combination thereof,
B ³ is at least one divalent inorganic-cation,
X ³ and Y ³ are, independently of each other, at least one monovalent anion,
k is a real number satisfying 0? k? 3,
The solvent is selected from the group consisting of dimethylformamide, dimethylsulfoxide, gamma -butyrolactone,
The non-solvent may be selected from the group consisting of alpha-terpineol, hexyl carbitol, butyl carbitol acetate, hexyl cellosolve, butyl cellosolve acetate, It is a combination of these. A light irradiation unit; A photodetector; And a control unit,
Wherein the photodetector comprises the photoelectric conversion element according to any one of claims 1 to 20.

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