A method for self-assembling modified dielectric layers and its application in perovskite transistors

Abstract

This invention discloses a method for self-assembling and modifying dielectric layers and its application in perovskite transistors, relating to the field of organic-inorganic metal halide perovskite field-effect transistors. Organic-inorganic metal halide perovskite films suffer from numerous defects and poor crystallinity. This invention employs molecular self-assembly to modify the dielectric layer, resulting in perovskite films with high crystallinity and good morphology, thereby fabricating perovskite field-effect transistors with high carrier mobility and a large current on / off ratio. This invention solves the problems of poor perovskite semiconductor layer film quality and low carrier mobility in current organic-inorganic metal halide perovskite field-effect transistors, thus enabling the acquisition of highly crystalline perovskite films. The dielectric layer prepared by this method can be applied to organic-inorganic metal halide perovskite field-effect transistors, playing a crucial role in the future industrialization of organic-inorganic metal halide perovskite field-effect transistors.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of organic-inorganic metal halide perovskite field effect transistors, and particularly relates to a method for self-assembling and modifying a dielectric layer and application thereof in a perovskite transistor. BACKGROUND

[0002] As a key component of modern electronic technology, field effect transistors have been widely used in various electronic products. As a new type of semiconductor material, organic-inorganic metal halide perovskite material has the characteristics of high mobility and solution processability, and its structure contains a shared corner metal halide octahedral inorganic framework throughout the thin film, which can promote carrier transport, thereby becoming a strong candidate for the next generation of field effect transistors, and is expected to be applied to display, sensor and storage technology in the future.

[0003] Although organic-inorganic metal halide perovskite field effect transistors have excellent electrical properties in theory, the quality of perovskite thin films is difficult to guarantee in actual preparation. There are various defects between the perovskite and the interface layer, which will cause high carrier trap density, capture carriers and produce unnecessary non-radiative recombination, resulting in the reduction of device performance. In addition, the transfer characteristics of organic-inorganic metal halide perovskite field effect transistors at room temperature also have large hysteresis. The above factors are not conducive to the preparation of large-area perovskite thin films with low defect state density and the production of high-performance transistors, and seriously hinder the commercialization process. SUMMARY

[0004] The purpose of the present application is to provide a method for self-assembling and modifying a dielectric layer to solve the problems of various defects in the perovskite semiconductor layer of the perovskite field effect transistor, poor thin film quality, high carrier trap density and insufficient excellent electrical properties.

[0005] To achieve the above purpose, the technical scheme adopted by the present application is as follows: the present application provides a method for self-assembling and modifying a dielectric layer. The self-assembled dielectric layer uses a molecular self-assembly method. Compared with a dielectric layer without a self-assembled layer, the self-assembled dielectric layer can effectively reduce the defects between the perovskite semiconductor layer and the dielectric layer, provide more nucleation sites at the interface, induce the preferred orientation of perovskite, and further improve the carrier transport efficiency.

[0006] The self-assembled layer molecules are chain molecules with an amino group at the first end and a carboxyl group at the end, or chain molecules with an amino group at the first end and a siloxane group at the end.

[0007] Further, the chain molecule with amino group at the head and carboxyl group at the tail includes 4-aminobenzoic acid (PABA), glycine, alanine, 4-aminobutyric acid (GABA), 5-aminopentanoic acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminohexanoic acid (7-AHA), 8-aminooctanoic acid (8-AOC).

[0008] Further, the chain molecule with amino group at the head and siloxane group at the tail includes 3-aminopropyltriethoxysilane (APTES), 4-amino-3,3-dimethylbutyltrimethoxysilane (ADBTMS).

[0009] The dielectric layer is one of oxide dielectric layer and polymer dielectric layer or a combination of one or more thereof.

[0010] Further, the oxide dielectric layer is one of Al2O3, HfO2, ZrO2, SiO2.

[0011] Further, the polymer dielectric layer is one of PVA (polyvinyl alcohol) and PVP (poly(4-vinylphenol)) polymers with hydroxyl group.

[0012] The application also provides a use of the self-assembled modified dielectric layer, and specifically, the self-assembled layer modified dielectric layer is used as the dielectric layer of the perovskite field effect transistor to prepare the perovskite field effect transistor, and the semiconductor layer is an organic-inorganic metal halide perovskite.

[0013] Further, the crystal structure of the organic-inorganic metal halide perovskite is ABX3, A is one or a combination of one or more of methylamine (MA + ), formamidinium (FA + ) and cesium (Cs + ) cations, B is one or a combination of one or more of tin (Sn 2+ ) and lead (Pb 2+ ) metal cations, and X is one or a combination of one or more of halide anions such as iodide (I - ), chloride (Cl - ) and bromide (Br - ).

[0014] Further, the structure of the perovskite field effect transistor prepared by using the self-assembled layer modified dielectric layer as the dielectric layer of the perovskite field effect transistor is bottom-gate top-contact or bottom-gate bottom-contact.

[0015] Further, by using the self-assembled layer modified dielectric layer as the dielectric layer of the perovskite field effect transistor, the perovskite semiconductor layer is prepared by spin coating, blade coating or evaporation, the source and drain electrodes are prepared, and the perovskite field effect transistor with bottom-gate top-contact or bottom-gate bottom-contact structure is obtained.

[0016] Through the above design scheme, the application can bring the following beneficial effects: the introduction of the self-assembled layer can effectively reduce the defects between the perovskite semiconductor layer and the dielectric layer, provide more nucleation sites at the interface, and induce the preferred orientation of the perovskite. The perovskite thin film is more inclined to grow in the vertical interface direction, and the perovskite thin film can be more fully laid on the surface of the dielectric layer, thereby improving the electrical performance of the perovskite field effect transistor. The performance of the device prepared by this method is higher than that of the dielectric layer without the self-assembled layer. BRIEF DESCRIPTION OF DRAWINGS

[0017] The application will be further described below in conjunction with the drawings and specific embodiments:

[0018] Figure 1 A bottom-gate top-contact field effect transistor structure schematic diagram of a perovskite field effect transistor with a self-assembled layer modified dielectric layer.

[0019] Figure 2 A bottom-gate bottom-contact field effect transistor structure schematic diagram of a perovskite field effect transistor with a self-assembled layer modified dielectric layer.

[0020] Figure 3 A thin film morphology diagram of a FASnI3 semiconductor layer of a bottom-gate top-contact structure perovskite field effect transistor with a 4-aminobenzoic acid modified SiO2 dielectric layer.

[0021] Figure 4 A thin film morphology diagram of a FASnI3 semiconductor layer of a bottom-gate top-contact structure perovskite field effect transistor with a 5-aminopentanoic acid modified SiO2 dielectric layer.

[0022] Figure 5 A thin film morphology diagram of a FASnI3 semiconductor layer of a bottom-gate bottom-contact structure perovskite field effect transistor with a 3-aminopropyl triethoxysilane modified SiO2 dielectric layer. 0.9 Cs 0.1 SnI3 semiconductor layer.

[0023] Figure 6 A transfer curve diagram of a bottom-gate top-contact structure perovskite field effect transistor with a 4-aminobenzoic acid modified SiO2 dielectric layer.

[0024] Figure 7 A transfer curve diagram of a bottom-gate top-contact structure perovskite field effect transistor with a 5-aminopentanoic acid modified SiO2 dielectric layer.

[0025] Figure 8 A transfer curve diagram of a bottom-gate bottom-contact structure perovskite field effect transistor with a 3-aminopropyl triethoxysilane modified SiO2 dielectric layer.

[0026] Marked description in the figure: 1 - self-assembled layer, 2 - perovskite semiconductor layer. DETAILED DESCRIPTION

[0027] The present application provides a method for self-assembled modification of dielectric layer, the self-assembled modification of dielectric layer is by molecular self-assembly.

[0028] The self-assembled layer molecules are one kind of chain molecules with amino group as the first end and carboxyl group as the last end, and another kind of chain molecules with amino group as the first end and siloxane as the last end.

[0029] The molecules with amino group as the first end and carboxyl group as the last end include 4-aminobenzoic acid (PABA), glycine, alanine, 4-aminobutyric acid (GABA), 5-aminopentanoic acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminohexanoic acid (7-AHA), and 8-aminooctanoic acid (8-AOC).

[0030] The molecules with amino group as the first end and siloxane as the last end include 3-aminopropyl triethoxysilane (APTES) and 4-amino-3, 3-dimethylbutyl trimethoxysilane (ADBTMS).

[0031] The oxide dielectric layer is one of Al2O3, HfO2, ZrO2, and SiO2.

[0032] The polymer dielectric layer is one of PVA (polyvinyl alcohol) and PVP (poly (4-vinyl phenol)) polymers with hydroxyl groups.

[0033] The semiconductor layer of the perovskite field effect transistor prepared by the self-assembled layer modified dielectric layer as the dielectric layer of the perovskite field effect transistor is an organic-inorganic metal halide perovskite.

[0034] The crystal structure of the organic-inorganic metal halide perovskite is ABX3, A is one or more than one combination of methylamine (MA + ), formamidinium (FA + ), and cesium (Cs + ) cations, B is one or more than one combination of tin (Sn 2+ ) and lead (Pb 2+ ) metal cations or their mixture, and X is one or more than one combination of halide anions such as iodine ion (I - ), chlorine ion (Cl - ), and bromine ion (Br - ).

[0035] The structure of the perovskite field effect transistor prepared by the self-assembled layer modified dielectric layer as the dielectric layer of the perovskite field effect transistor is bottom gate top contact or bottom gate bottom contact.

[0036] The molecular structures of PABA, Glycine, Alanine, GABA, 5-AVA, 6-ACA, 7-AHA, 8-AOC, APTES, and ADBTMS are shown in Table 1; the molecular structures of PVA and PVP are shown in Table 2.

[0037] To better understand the purpose, structure, and function of this invention, the following detailed description, in conjunction with the accompanying drawings, provides a self-assembled layer modified dielectric layer, its preparation method, and its application.

[0038] Specific related embodiments of the present invention are as follows:

[0039] Example 1

[0040] A method for self-assembling modified dielectric layers includes the following steps:

[0041] The SiO2 dielectric layer was cleaned, then immersed in a 4-aminobenzoic acid solution for a period of time, and cleaned again to obtain a 4-aminobenzoic acid self-assembled layer modified dielectric layer. Figure 1 Self-assembly layer 1 in the middle.

[0042] Example 2

[0043] A method for self-assembling modified dielectric layers includes the following steps:

[0044] The SiO2 dielectric layer was cleaned, then immersed in a 5-aminovaleric acid solution for a period of time, and then cleaned again to obtain a 5-aminovaleric acid self-assembled layer modified dielectric layer. Figure 1 Self-assembly layer 1 in the middle.

[0045] Example 3:

[0046] A method for self-assembling modified dielectric layers includes the following steps:

[0047] The HfO2 dielectric layer was cleaned, then immersed in an alanine solution for a period of time, and cleaned again to obtain an alanine self-assembled layer modified dielectric layer. Figure 1 Self-assembly layer 1 in the middle.

[0048] Example 4

[0049] A method for self-assembling modified dielectric layers includes the following steps:

[0050] The SiO2 dielectric layer was cleaned, then immersed in a 3-aminopropyltriethoxysilane solution for a period of time, and cleaned again to obtain a 3-aminopropyltriethoxysilane self-assembled layer modified dielectric layer. Figure 2 Self-assembly layer 1 in the middle.

[0051] Example 5:

[0052] A method for self-assembling modified dielectric layers includes the following steps:

[0053] The PVA dielectric layer was cleaned, then immersed in a 4-amino-3,3-dimethylbutyltrimethoxysilane solution for a period of time, followed by cleaning, to obtain a 4-amino-3,3-dimethylbutyltrimethoxysilane self-assembled layer modified dielectric layer. Figure 2 Self-assembly layer 1 in the middle.

[0054] Example 6:

[0055] The process for fabricating a perovskite field-effect transistor with a bottom-gate top-contact structure and a semiconductor layer of FASnI3 is as follows:

[0056] (1) On the self-assembled layer modified dielectric layer obtained in Example 1, a FASnI3 semiconductor layer is spin-coated, i.e. Figure 1 The perovskite semiconductor layer 2 in the middle has the following thin film morphology: Figure 3 As shown;

[0057] (2) Based on the semiconductor layer obtained in step (1), Au is deposited as the source and drain electrodes to fabricate a perovskite field-effect transistor. The device structure is as follows: Figure 1 As shown. The transfer curve of the fabricated perovskite field-effect transistor is shown in the figure. Figure 6 As shown, the obtained mobility is 2.57 cm. 2 V -1 s -1 The threshold voltage is 1.20V and the on / off ratio is 10. 5 .

[0058] Example 7:

[0059] The process for fabricating a perovskite field-effect transistor with a bottom-gate top-contact structure and a semiconductor layer of FASnI3 is as follows:

[0060] (1) On the self-assembled layer modified dielectric layer obtained in Example 2, a FASnI3 semiconductor layer is spin-coated, i.e. Figure 1 The perovskite semiconductor layer 2 in the middle has the following thin film morphology: Figure 4 As shown;

[0061] (2) Based on the semiconductor layer obtained in step (1), Au is deposited as the source and drain electrodes to fabricate a perovskite field-effect transistor. The transfer curve of the fabricated perovskite field-effect transistor is shown in the figure. Figure 7 As shown. The mobility is 4.15 cm. 2 V -1 s -1 The threshold voltage is 2.40V and the on / off ratio is 10. 6 .

[0062] Example 8:

[0063] The semiconductor layer is fabricated using FA. 0.5 MA 0.3 Cs 0.2 The process of a perovskite field-effect transistor with a bottom-gate top-contact PbI2Cl structure is as follows:

[0064] (1) On the self-assembled layer modified dielectric layer obtained in Example 3, FA was spin-coated. 0.5 MA 0.3 Cs 0.2 PbI2Cl semiconductor layer, i.e. Figure 1 The perovskite semiconductor layer 2 in the middle;

[0065] (2) Based on the semiconductor layer obtained in step (1), Au is deposited as the source and drain electrodes to prepare a perovskite field-effect transistor.

[0066] Example 9:

[0067] The semiconductor layer is fabricated using FA. 0.9 Cs 0.1 The process of SnI3 bottom-gate bottom-contact perovskite field-effect transistor is as follows:

[0068] (1) Au was deposited as source and drain electrodes on the self-assembled layer modified dielectric layer obtained in Example 4;

[0069] (2) Based on the source and drain electrodes obtained in step (1), spin-coat FA. 0.9 Cs 0.1 SnI3 semiconductor layer, i.e. Figure 2 The perovskite semiconductor layer 2 in the middle has the following thin film morphology: Figure 5 As shown, a perovskite field-effect transistor is fabricated, and the device structure is as follows. Figure 2 As shown. The transfer curve of the fabricated perovskite field-effect transistor is shown in the figure. Figure 8 As shown, the mobility is 0.45 cm. 2 V -1 s -1 The threshold voltage is 4.40V and the on / off ratio is 10. 5 .

[0070] Example 10:

[0071] The semiconductor layer is fabricated using FA. 0.5 MA 0.5 SnI 2.76 Br 0.05 Cl 0.19 The process of a perovskite field-effect transistor with a bottom-gate bottom-contact structure is as follows:

[0072] (1) Au was deposited as source and drain electrodes on the self-assembled layer modified dielectric layer obtained in Example 5;

[0073] (2) Based on the source and drain electrodes obtained in step (1), spin-coat FA. 0.5 MA 0.5 SnI 2.76 Br 0.05 Cl 0.19 Semiconductor layer, i.e. Figure 2 In the perovskite semiconductor layer 2, a perovskite field-effect transistor is fabricated.

[0074] It is understood that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

[0075] The general formula of the self-assembled molecule with an amino group at the beginning and a carboxyl group at the end in this invention is shown below, where R is a carbon chain or a benzene ring and its derivatives.

[0076] H2N-R-COOH

[0077] The general formula of the self-assembled molecule with an amino group at the beginning and a siloxane group at the end in this invention is shown below, where R, R1, R2, and R3 are carbon chains.

[0078]

[0079] Table 1

[0080]

[0081] Table 2

[0082]

Claims

1. Use of a self-assembled modified dielectric layer in a perovskite transistor, characterized in that, The perovskite field effect transistor is prepared by using the self-assembled layer modified dielectric layer as the dielectric layer of the perovskite field effect transistor, the semiconductor layer is an organic-inorganic metal halide perovskite, the self-assembled layer molecules can be self-assembled on the dielectric layer, and the self-assembled layer molecules are chain molecules with an amino group at the first end and a carboxyl group at the tail end or chain molecules of siloxane; the self-assembled layer is in contact with the semiconductor layer.

2. Use according to claim 1, characterized in that, The crystal structure of the organic-inorganic metal halide perovskite is ABX3, A is one or more combinations of methylamine (MA + ), formamidinium (FA + ), and cesium (Cs + ) cations, B is tin (Sn 2+ ) and lead (Pb 2+ ) metal cations or a mixture thereof, and X is one or more of iodine (I - ), chlorine (Cl - ), and bromine (Br - ) ions.

3. Use according to claim 1, characterized in that, The perovskite field effect transistor prepared by using the self-assembled modified dielectric layer as the dielectric layer of the perovskite field effect transistor has a bottom-gate top-contact structure or a bottom-gate bottom-contact structure.

4. Use according to any one of claims 1 to 3, characterized in that, The perovskite field effect transistor is prepared by using the self-assembled modified dielectric layer as the dielectric layer of the perovskite field effect transistor, preparing the perovskite semiconductor layer by a spin coating method, a doctor blade method or an evaporation method, and preparing a source-drain electrode, so that the perovskite field effect transistor with a bottom-gate top-contact structure or a bottom-gate bottom-contact structure is obtained.

5. The use according to claim 1, characterized in that, The chain molecules with an amino group at the first end and a carboxyl group at the tail end include 4-aminobenzoic acid (PABA), glycine, alanine, 4-aminobutyric acid (GABA), 5-aminopentanoic acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminohexanoic acid (7-AHA) and 8-aminooctanoic acid (8-AOC).

6. Use according to claim 1, characterized in that, The chain molecules with an amino group at the first end and a siloxane at the tail end include 3-aminopropyl triethoxysilane (APTES) and 4-amino-3,3-dimethylbutyl trimethoxysilane (ADBTMS).

7. Use according to claim 1, characterized in that, The dielectric layer is one of an oxide dielectric layer and a polymer dielectric layer or a combination of one or more than one thereof.

8. Use according to claim 7, characterized in that, The oxide dielectric layer is one of Al2O3, HfO2, ZrO2 and SiO2.

9. Use according to claim 7, characterized in that, The polymer dielectric layer is one of PVA and PVP polymers with a hydroxyl group.

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