Method for modifying dielectric layer through self-assembly and application of method in perovskite transistor

Abstract

The invention discloses a method for self-assembly modification of a dielectric layer and application of the method in a perovskite transistor, and relates to the field of organic and inorganic metal halide perovskite field effect transistors. The organic and inorganic metal halide perovskite thin film has many defects and poor crystallization quality. The dielectric layer is modified by molecular self-assembly, and the perovskite thin film prepared on the dielectric layer is high in crystallinity and good in morphology, so that the perovskite field effect transistor with high carrier mobility and large current switching ratio is prepared. According to the invention, the problems of poor perovskite semiconductor layer film quality and low carrier mobility in the existing organic and inorganic metal halide perovskite field effect transistor are solved, so that the perovskite film with high crystallinity can be obtained. The dielectric layer prepared by the method can be applied to the organic and inorganic metal halide perovskite field effect transistor, and plays a crucial role in the future industrialization process of the organic and inorganic metal halide perovskite field effect transistor.

Description

Technical Field

[0001] The invention belongs to the technical field of organic and inorganic metal halide perovskite field effect transistors, and in particular relates to a method for self-assembly modifying a dielectric layer and an application thereof in a perovskite transistor. Background Art

[0002] As a key component of modern electronic technology, field effect transistors have been widely used in various electronic products. Organic-inorganic metal halide perovskite materials, as an emerging semiconductor material, have the characteristics of high mobility and solution processability. At the same time, their structure contains a shared corner metal halide octahedral inorganic framework throughout the film, which can promote carrier transport, making them a strong candidate for the next generation of field effect transistors, and are expected to be used in display, sensor and storage technologies in the future.

[0003] Although organic-inorganic metal halide perovskite field-effect transistors have excellent electrical properties in theory, the quality of perovskite films is difficult to guarantee in actual preparation. There are many defects inside the perovskite and between the interface layers, resulting in high carrier trap density, which will capture carriers to produce unnecessary non-radiative recombination, resulting in reduced 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 large-scale preparation of perovskite films with low defect state density and the production of high-performance transistors, which seriously hinders the progress of their commercial application. Summary of the invention

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

[0005] To achieve the above-mentioned purpose, the present invention adopts the following technical scheme: the present invention provides a method for self-assembly modifying a dielectric layer, wherein the self-assembly modifying dielectric layer adopts a molecular self-assembly method, and compared with a dielectric layer without a self-assembly layer, the self-assembled modified 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 preferential orientation of the perovskite, and thus improve the carrier transmission efficiency.

[0006] One type of the self-assembly layer molecules is a chain molecule with an amino group at the first end and a carboxyl group at the end, and the other type is a chain molecule with an amino group at the first end and a siloxane group at the end.

[0007] Furthermore, the chain molecules with an amino group at the first end and a carboxyl group at the end include 4-aminobenzoic acid (PABA), glycine, alanine, 4-aminobutyric acid (GABA), 5-aminovaleric acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminoheptanoic acid (7-AHA), and 8-aminooctanoic acid (8-AOC).

[0008] Furthermore, the chain molecules with an amino group at the first end and a siloxane at the end include 3-aminopropyltriethoxysilane (APTES) and 4-amino-3,3-dimethylbutyltrimethoxysilane (ADBTMS).

[0009] The dielectric layer is one of an oxide dielectric layer and a polymer dielectric layer, or a combination of more than one of them.

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

[0011] Furthermore, the polymer dielectric layer is a polymer having a hydroxyl group such as PVA (polyvinyl alcohol) or PVP (poly (4-vinylphenol)).

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

[0013] Furthermore, the crystal structure of organic-inorganic metal halide perovskite is ABX3, where A is methylamine (MA + ), formamidine (FA + ) and cesium (Cs + ) cations, one or more of which are combined, B is tin (Sn 2+ ) and lead (Pb 2+ ) metal cations or mixtures thereof, X is an iodide ion (I - ), chloride ion (Cl - ), bromide ion (Br - ) and other halogen anions.

[0014] Furthermore, 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] Furthermore, the dielectric layer modified with the self-assembled layer is used as the dielectric layer of the perovskite field effect transistor, and the perovskite semiconductor layer is prepared by spin coating, scraping or evaporation, and the source and drain electrodes are prepared to obtain a perovskite field effect transistor with a bottom gate top contact or bottom gate bottom contact structure.

[0016] Through the above design scheme, the present invention 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 film tends to grow in the direction perpendicular to the interface, and the perovskite film can be spread more fully 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 THE DRAWINGS

[0017] The present invention is further described below with reference to the accompanying drawings and specific embodiments:

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

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

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

[0021] Figure 4 Thin film morphology of the FASnI3 semiconductor layer of the bottom-gate top-contact perovskite field effect transistor with 5-aminovaleric acid modified SiO2 dielectric layer.

[0022] Figure 5 FA of bottom-gate bottom-contact perovskite field-effect transistor with 3-aminopropyltriethoxysilane modified SiO2 dielectric layer 0.9 Cs 0.1 Thin film morphology of SnI3 semiconductor layer.

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

[0024] Figure 7 The transfer curve of the bottom-gate top-contact perovskite field effect transistor with 5-aminovaleric acid modified SiO2 dielectric layer.

[0025] Figure 8 The transfer curve of the bottom-gate bottom-contact structure perovskite field effect transistor with 3-aminopropyltriethoxysilane modified SiO2 dielectric layer.

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

[0027] The invention provides a method for self-assembly modifying a dielectric layer. The self-assembly modified dielectric layer adopts molecular self-assembly.

[0028] One type of self-assembling layer molecules is a chain molecule with an amino group at the first end and a carboxyl group at the end, and the other type is a chain molecule with an amino group at the first end and a siloxane group at the end.

[0029] Molecules with an amino group at the first end and a carboxyl group at the end include 4-aminobenzoic acid (PABA), glycine, alanine, 4-aminobutyric acid (GABA), 5-aminovaleric acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminoheptanoic acid (7-AHA), and 8-aminooctanoic acid (8-AOC).

[0030] Molecules with an amino group at the head end and a siloxane at the end include 3-aminopropyltriethoxysilane (APTES) and 4-amino-3,3-dimethylbutyltrimethoxysilane (ADBTMS).

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

[0032] The polymer dielectric layer is a polymer such as PVA (polyvinyl alcohol) or PVP (poly (4-vinylphenol)) having a hydroxyl group.

[0033] The semiconductor layer 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 organic-inorganic metal halide perovskite.

[0034] The crystal structure of organic-inorganic metal halide perovskite is ABX3, where A is methylamine (MA + ), formamidine (FA + ) and cesium (Cs + ) cations, one or more of which are combined, B is tin (Sn 2+ ) and lead (Pb 2+ ) metal cations or mixtures thereof, X is an iodide ion (I - ), chloride ion (Cl - ), bromide ion (Br - ) and other halogen anions.

[0035] 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.

[0036] The specific 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] In order to better understand the purpose, structure and function of the present invention, the following is a further detailed description of a self-assembled layer modified dielectric layer and its preparation method and application proposed by the present invention in conjunction with the accompanying drawings.

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

[0039] Example 1

[0040] A method for self-assembly modifying a dielectric layer comprises the following steps:

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

[0042] Example 2

[0043] A method for self-assembly modifying a dielectric layer comprises the following steps:

[0044] The SiO2 dielectric layer is 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, that is, Figure 1 Self-assembled layer 1.

[0045] Embodiment 3:

[0046] A method for self-assembly modifying a dielectric layer comprises the following steps:

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

[0048] Example 4

[0049] A method for self-assembly modifying a dielectric layer comprises the following steps:

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

[0051] Embodiment 5:

[0052] A method for self-assembly modifying a dielectric layer comprises the following steps:

[0053] The PVA dielectric layer is cleaned, then immersed in a 4-amino-3,3-dimethylbutyltrimethoxysilane solution for a period of time, and then cleaned to obtain a 4-amino-3,3-dimethylbutyltrimethoxysilane self-assembled layer modified dielectric layer, that is, Figure 2 Self-assembled layer 1.

[0054] Embodiment 6:

[0055] The process of preparing 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 was spin-coated, that is, Figure 1 The perovskite semiconductor layer 2 in the film has a morphology such as Figure 3 As shown;

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

[0058] Embodiment 7:

[0059] The process of preparing 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 was spin-coated, that is, Figure 1 The perovskite semiconductor layer 2 in the film has a morphology such as Figure 4 As shown;

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

[0062] Embodiment 8:

[0063] Preparation of semiconductor layer as FA 0.5 MA 0.3 Cs 0.2 The process of the perovskite field effect transistor with bottom gate and top contact structure of PbI2Cl is as follows:

[0064] (1) Spin-coat FA on the self-assembled layer modified dielectric layer obtained in Example 3 0.5 MA 0.3 Cs 0.2 PbI2Cl semiconductor layer, that is Figure 1 The perovskite semiconductor layer 2;

[0065] (2) On the basis of the semiconductor layer obtained in step (1), Au is evaporated as source and drain electrodes to prepare a perovskite field effect transistor.

[0066] Embodiment 9:

[0067] Preparation of semiconductor layer as FA 0.9 Cs 0.1 The perovskite field effect transistor process of SnI3 bottom gate bottom contact structure is:

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

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

[0070] Embodiment 10:

[0071] Preparation of semiconductor layer as FA 0.5 MA 0.5 Sn 2.76 Br 0.05 Cl 0.19 The process of the bottom-gate bottom-contact perovskite field effect transistor is:

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

[0073] (2) On the source-drain electrode obtained in step (1), spin-coat FA 0.5 MA 0.5 Sn 2.76 Br 0.05 Cl 0.19 The semiconductor layer, i.e. Figure 2 The perovskite semiconductor layer 2 in the preparation of a perovskite field effect transistor.

[0074] It should be 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 in the protection scope of the present invention.

[0075] The general formula of the self-assembling molecule with an amino group at the first end and a carboxyl group at the terminal end in the present invention is shown below, wherein R is a carbon chain or a benzene ring and its derivatives.

[0076] H2N-R-COOH

[0077] The general formula of the self-assembly molecule with an amino group at the first end and a siloxane at the end is shown below, wherein R, R1, R2, and R3 are carbon chains.

[0078]

[0079] Table 1

[0080]

[0081] Table 2

[0082]

Claims

1. A method for self-assembly modifying a dielectric layer, characterized in that: The self-assembled layer molecules can self-assemble on the dielectric layer.

2. A method for self-assembly modifying a dielectric layer according to claim 1, characterized in that: The self-assembly layer molecules are chain molecules with an amino group at the first end and a carboxyl group at the end.

3. The method for self-assembly modifying a dielectric layer according to claim 1, characterized in that: The self-assembly layer molecules are chain molecules with an amino group at the first end and a siloxane at the end.

4. A method for self-assembly modifying a dielectric layer according to claim 2, characterized in that: The chain molecules with an amino group at the head end and a carboxyl group at the end include 4-aminobenzoic acid (PABA), glycine (Glycine), alanine (Alanine), 4-aminobutyric acid (GABA), 5-aminovaleric acid (5-AVA), 6-aminohexanoic acid (6-ACA), 7-aminoheptanoic acid (7-AHA), and 8-aminooctanoic acid (8-AOC).

5. The method for self-assembly modifying a dielectric layer according to claim 3, characterized in that: The chain molecules with an amino group at the head end and a siloxane at the end include 3-aminopropyltriethoxysilane (APTES) and 4-amino-3,3-dimethylbutyltrimethoxysilane (ADBTMS).

6. The method for self-assembly modifying a dielectric layer 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 more than one of them.

7. A method for self-assembly modifying a dielectric layer according to claim 6, characterized in that: The oxide dielectric layer is one of Al2O3, HfO2, ZrO2, and SiO2.

8. The method for self-assembly modifying a dielectric layer according to claim 6, characterized in that: The polymer dielectric layer is a PVA or PVP polymer having hydroxyl groups.

9. Application of a self-assembled modified dielectric layer in a perovskite transistor, characterized in that: The semiconductor layer of the perovskite field effect transistor prepared by using a self-assembled modified dielectric layer obtained by the method according to any one of claims 1 to 8 as the dielectric layer of the perovskite field effect transistor is an organic-inorganic metal halide perovskite.

10. The use according to claim 9, characterized in that: The crystal structure of the organic-inorganic metal halide perovskite is ABX3, where A is methylamine (MA + ), formamidine (FA + ) and cesium (Cs + ) cations, one or more of which are combined, B is tin (Sn 2+ ) and lead (Pb 2+ ) metal cations or mixtures thereof, X is an iodide ion (I - ), chloride ion (Cl - ), bromide ion (Br - ) one or more of them.

11. The use according to claim 9, characterized in that: The structure of the perovskite field effect transistor prepared by using the self-assembled modified dielectric layer as the dielectric layer of the perovskite field effect transistor is bottom gate top contact or bottom gate bottom contact.

12. The use according to any one of claims 9 to 11, characterized in that: The self-assembled modified dielectric layer is used as the dielectric layer of the perovskite field effect transistor, and the perovskite semiconductor layer is prepared by spin coating, scraping or evaporation, and the source and drain electrodes are prepared to obtain a perovskite field effect transistor with a bottom gate top contact or bottom gate bottom contact structure.

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