Method for preparing rhenium disulfide film in two steps

Abstract

The invention discloses a method for preparing a rhenium disulfide film in two steps, and belongs to the technical field of semiconductor material preparation. In the first step, rhenium heptoxide is fused into molten soda-lime glass to serve as a rhenium source. 2, under the catalysis of sodium ions, sulfur powder and rhenium heptoxide react in the molten soda-lime glass to generate rhenium disulfide, the rhenium disulfide is diffused to the surface of the molten glass, and finally, under the driving of carrier gas, the rhenium disulfide is deposited on a mica substrate above to form a continuous film. The high-quality rhenium disulfide thin film synthesized on the mica substrate is expected to promote further application of the high-quality rhenium disulfide thin film in electrical devices.

Description

Technical Field

[0001] The invention belongs to the technical field of semiconductor material preparation, and in particular relates to a two-step method for preparing a rhenium disulfide film. Background Art

[0002] Two-dimensional transition metal chalcogenides (TMDCs) are a class of layered materials that are connected by covalent bonds in the plane and interact with each other by van der Waals forces. Among the many two-dimensional TMDCs materials, rhenium disulfide (ReS2) has an asymmetric crystal structure, and its in-plane anisotropic optical and electrical properties and excellent environmental stability make it have potential application value in the fields of polarization photodetection devices.

[0003] In the preparation of ReS2 by chemical vapor deposition (CVD), rhenium source is a focus of current research. A good rhenium source needs to have high reactivity and moderate evaporation rate. Commonly used rhenium sources include mixtures of rhenium and tellurium, rhenium oxides, etc., but there are still some problems in controllability. For example, when rhenium heptoxide (Re2O7) is used as a rhenium source, although the reactivity is high, Re2O7 evaporates easily, resulting in a large nucleation density and easy formation of particles rather than films. Therefore, the optimization of rhenium source is a key issue in the study of CVD preparation of ReS2 thin films, which has important research significance for both basic research and practical applications of ReS2 thin films. Summary of the invention

[0004] The purpose of the present invention is to provide a two-step method for preparing ReS2 thin film, wherein the first step is to melt Re2O7 into soda-lime glass as a rhenium source, and the second step is to cause a ReS2 synthesis reaction at the molten soda-lime glass, thereby preparing a high-quality ReS2 thin film on a mica substrate, and further promoting its application in electrical devices.

[0005] The technical solution adopted by the present invention is as follows:

[0006] A two-step method for preparing a ReS2 thin film comprises the following steps:

[0007] (1) Cleaning the graphite boat and substrate: The graphite boat, centimeter-sized soda-lime glass and mica substrate were placed in acetone ultrasound for 15 min, anhydrous ethanol for 15 min, and deionized water for 15 min, and then dried with a nitrogen gun.

[0008] (2) Preparation of rhenium source: a) Weigh Re2O7 powder with an electronic scale, spread the weighed Re2O7 powder on a graphite boat, cover it with soda-lime glass, and then place it in the graphite boat and send it into the central temperature zone of the tube furnace, such as Figure 1As shown; b) In an atmospheric atmosphere, the central temperature zone is heated to a certain temperature and kept warm for a certain period of time so that Re2O7 enters the molten soda-lime glass, and then naturally cooled to room temperature to obtain the rhenium source for the next step of growth.

[0009] (3) Preparation of ReS2 film: a) Weigh sulfur powder (S) with an electronic scale, and feed the weighed S powder and soda-lime glass containing Re2O7 into the first and second temperature zones of a tube furnace respectively, and place a mica substrate on top of the soda-lime glass. Figure 2 As shown; b) In an argon atmosphere, the first temperature zone and the second temperature zone are heated to 110°C, kept warm for 10 minutes, and water vapor is removed; c) The first temperature zone and the second temperature zone are heated to the growth temperature respectively, and then kept warm for the growth time under atmospheric pressure to grow the ReS2 film, and finally naturally cooled to room temperature to obtain the ReS2 film.

[0010] Furthermore, in step (2), the mass of Re2O7 powder is 10-100 mg.

[0011] Furthermore, in step (2), the temperature of the central temperature zone is 700-1000°C.

[0012] Furthermore, in step (2), the growth time is 30-60 min.

[0013] Furthermore, in step (3), the mass of S powder is 30-2000 mg.

[0014] Furthermore, in step (3), the argon gas flow rate is 10-200 sccm.

[0015] Furthermore, in step (3), the temperature in the first temperature zone is 150-350°C.

[0016] Furthermore, in step (3), the temperature of the second temperature zone is 750-900°C.

[0017] Furthermore, in step (3), the growth time is 5-60 min.

[0018] In summary, by adopting the above technical solution, the beneficial effects of the present invention are:

[0019] (1) In the present invention, in step (2), since Re2O7 is placed under the soda-lime glass, although the melting point of Re2O7 is lower than that of the soda-lime glass, Re2O7 can still be well integrated into the molten soda-lime glass as a rhenium source.

[0020] (2) In the present invention, in step (3), under the catalytic effect of Na ions, S and Re2O7 react inside the molten soda-lime glass to generate ReS2; then, ReS2 diffuses to the surface of the molten glass; finally, driven by the carrier gas, it is deposited on the upper mica substrate to form a continuous film. The presence of Na ions will effectively reduce the formation barrier of ReS2, thereby promoting the lateral growth of crystal domains and inhibiting the formation of defects, thereby forming a high-quality film.

[0021] (3) In the present invention, the number of layers of the ReS2 film can be controlled by the quality of Re2O7 in step (2) and the growth time in step (3). BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0023] Figure 1 This is a schematic diagram of the first step device for preparing ReS2 film in the present invention.

[0024] Figure 2 It is a schematic diagram of the second step device for preparing ReS2 film in the present invention. DETAILED DESCRIPTION

[0025] In order to make the purpose, technical scheme and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention, that is, the embodiments described are only part of the embodiments of the present invention, rather than all of the embodiments. The components of the embodiments of the present invention described and shown in the drawings herein can be arranged and designed in various different configurations.

[0026] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without making creative work are within the scope of protection of the present invention.

[0027] It should be noted that relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise a ..." do not exclude the existence of other identical elements in the process, method, article or device including the elements.

[0028] The features and performance of the present invention are further described in detail below in conjunction with the embodiments.

[0029] Example 1

[0030] (1) Cleaning the graphite boat and substrate: Separately clean the graphite boat, ~1×1 cm 2 The soda-lime glass and mica substrates were placed in acetone ultrasound for 15 min, anhydrous ethanol for 15 min, deionized water for 15 min, and dried with a nitrogen gun.

[0031] (2) Preparation of rhenium source: a) Weigh 20 mg of Re2O7 powder using an electronic scale, spread the weighed Re2O7 powder evenly on a graphite boat, cover it with soda-lime glass, and then place it in the graphite boat and send it into the central temperature zone of a tube furnace, such as Figure 1 As shown; b) In an atmospheric atmosphere, the central temperature zone is heated to 750°C and kept warm for 30 minutes to allow Re2O7 to enter the molten soda-lime glass, and then naturally cooled to room temperature to obtain the rhenium source for the next step of growth.

[0032] (3) Preparation of ReS2 film: a) Weigh 200 mg of S powder using an electronic scale, and feed the weighed S powder and soda-lime glass containing Re2O7 into the first and second temperature zones of a tube furnace respectively. Place a mica substrate on top of the soda-lime glass. Figure 2 As shown; b) In an argon atmosphere, the first temperature zone and the second temperature zone are heated to 110°C, kept warm for 10 minutes, and water vapor is removed; c) The first temperature zone and the second temperature zone are heated to 180°C and 800°C respectively, and then kept warm for 30 minutes at atmospheric pressure to grow the ReS2 film, and finally naturally cooled to room temperature to obtain the ReS2 film.

[0033] 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.

Claims

1. A two-step method for preparing a rhenium disulfide (ReS2) thin film, comprising the following steps: (1) Cleaning the graphite boat and substrate: The graphite boat, centimeter-sized soda-lime glass and mica substrate were placed in acetone ultrasound for 15 min, anhydrous ethanol for 15 min, and deionized water for 15 min, and then dried with a nitrogen gun. (2) Preparation of rhenium source: a) Weigh Re2O7 powder with an electronic scale, spread the weighed Re2O7 powder evenly on a graphite boat, cover it with soda-lime glass, and then place it in the graphite boat and send it into the central temperature zone of a tube furnace, as shown in Figure 1; b) In an atmospheric atmosphere, heat the central temperature zone to a certain temperature and keep it warm for a certain period of time so that Re2O7 enters the molten soda-lime glass, and then naturally cool it to room temperature to obtain the rhenium source used for the next step of growth. (3) Preparation of ReS2 thin film: a) Weigh sulfur powder (S) with an electronic scale, and send the weighed S powder and soda-lime glass containing Re2O7 into the first and second temperature zones of the tube furnace respectively, and place the mica substrate on top of the soda-lime glass, as shown in Figure 2; b) In an argon atmosphere, heat the first and second temperature zones to 110°C, keep them warm for 10 minutes, and remove water vapor; c) Heat the first and second temperature zones to the growth temperature respectively, and then keep them warm for the growth time under atmospheric pressure to grow ReS2 thin film, and finally cool them naturally to room temperature to obtain ReS2 thin film.

2. A two-step method for preparing ReS2 thin film according to claim 1, characterized in that: In step (2), since Re2O7 is placed under the soda-lime glass, although the melting point of Re2O7 is lower than that of the soda-lime glass, Re2O7 can still be well integrated into the molten soda-lime glass as a rhenium source.

3. The method for preparing ReS2 thin film in two steps according to claim 1, characterized in that: In step (3), under the catalytic action of Na ions, S and Re2O7 react inside the molten soda-lime glass to generate ReS2; then, ReS2 diffuses to the surface of the molten glass; finally, driven by the carrier gas, it is deposited on the mica substrate above to form a continuous film. The presence of Na ions will effectively reduce the formation barrier of ReS2, thereby promoting the lateral growth of crystal domains and inhibiting the formation of defects, thereby forming a high-quality film.

4. The method for preparing ReS2 thin film in two steps according to claim 1, characterized in that: The number of layers of the ReS2 film can be controlled by the quality of Re2O7 in step (2) and the growth time in step (3).

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