A method for preparing a binary compound

Abstract

This application provides a method for preparing a binary compound, comprising: step S1: forming a first thin film and a second thin film on a substrate; step S2: forming binary compounds with different phase ratios by chemical vapor deposition of the first thin film and the second thin film, wherein, in step S1, the content of the first thin film and the second thin film is controlled by the thickness of the first thin film and the second thin film, and in step S2, the generation of binary compounds with different phase ratios is controlled by controlling the thickness ratio of the first thin film and the second thin film. The method for preparing a binary compound provided by this invention can achieve large-area controllable phase transition of the binary compound.

Description

Technical Field

[0001] This application belongs to the field of semiconductor materials technology, and in particular relates to a method for preparing a binary compound. Background Technology

[0002] With the rapid development of modern electronic information technology, the silicon-based integrated circuit industry has entered the "post-Moore era." The miniaturization of transistor size and the improvement of performance face various technical obstacles, thus requiring the development and research of new materials and new processes.

[0003] Two-dimensional semiconductor materials are among the most promising materials for developing next-generation electronic and optoelectronic devices, possessing characteristics such as atomic-level thickness, suitable band gaps, and high mobility. The preparation methods for two-dimensional transition metal chalcogenides mainly fall into two categories: top-down and bottom-up. The bottom-up approach involves physical or chemical synthesis methods to prepare two-dimensional materials. Chemical vapor deposition (CVD) is currently the mainstream method for preparing two-dimensional materials. CVD-prepared two-dimensional materials offer advantages such as a wide synthesis range, controllable layer number, and the ability to achieve wafer-level fabrication. Furthermore, it is compatible with silicon-based materials, making it an essential material synthesis method for next-generation semiconductor processes.

[0004] As can be seen from the phase diagram, many transition metal chalcogenides have a variety of phases, but currently only common phases are available. Because many phases have high requirements for temperature and element ratio, many phases have not been prepared in a controllable manner.

[0005] Therefore, how to controllably prepare each phase in a material system using chemical vapor deposition is a pressing problem that needs to be solved in the controllable phase growth and large-area preparation of two-dimensional materials. Summary of the Invention

[0006] In view of the problems existing in the above-mentioned related technologies, the present invention provides a method for preparing binary compounds, which can realize large-area controllable phase transition of binary compounds.

[0007] Therefore, this application provides a method for preparing a binary compound, comprising:

[0008] Step S1: Form a first thin film and a second thin film on the substrate;

[0009] Step S2: The first film and the second film are subjected to chemical vapor deposition to generate binary compounds with different phase ratios.

[0010] In step S1, the content of the first film and the second film is controlled by the thickness of the first film and the second film. In step S21, the generation of the binary compound with different phase ratios is controlled by controlling the thickness ratio of the first film and the second film.

[0011] In some embodiments, step S1 includes: generating the first thin film and the second thin film on the substrate by magnetron sputtering.

[0012] In some embodiments, step S1 includes: forming the first thin film and the second thin film on the substrate by electron beam evaporation deposition.

[0013] In some embodiments, step S2 is characterized in that: the substrate on which the first thin film and the second thin film are grown is placed in a quartz boat, and then the quartz boat is placed in a tube furnace for chemical vapor deposition.

[0014] In some embodiments, the substrate includes a first substrate and a second substrate, step S1 includes: forming the first thin film on the first substrate and forming the second thin film on the second substrate, and step S2 includes: placing the first thin film formed on the first substrate above the second thin film formed on the second substrate, wherein the first thin film and the second thin film are used to form binary compound films with different phase ratios by chemical vapor deposition.

[0015] In some embodiments, the substrate includes a conductive layer and an insulating layer, the conductive layer being disposed above the insulating layer.

[0016] In some embodiments, the first film is a Te film and the second film is a Pd film.

[0017] In some embodiments, the first film is a Te film and the second film is a Mo film.

[0018] In some embodiments, the first film is a Se film and the second film is a Pd film.

[0019] In some embodiments, the substrate is a silicon / silicon oxide substrate.

[0020] In the binary compound preparation method provided by the present invention, a first thin film and a second thin film are generated on a substrate, and the content of the two elements participating in the reaction is controlled by controlling the thickness ratio of the first thin film and the second thin film. At the same reaction temperature, the generation of binary compounds with different phases can be controlled. That is, the binary compound preparation method according to the embodiments of the present application can realize large-area controllable phase transition of two-dimensional binary compounds. Attached Figure Description

[0021] To more clearly illustrate the technical solutions in the embodiments or related technologies of this application, the accompanying drawings used in the description of the embodiments or related technologies will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0022] Figure 1 A schematic flowchart illustrating the preparation method of the binary compound provided in this embodiment of the invention;

[0023] Figure 2 This is a schematic diagram of a simulated reaction for the preparation method of the binary compound provided in Embodiment 1 of the present invention;

[0024] Figure 3 This is a schematic diagram of a simulated reaction for the preparation method of the binary compound provided in Example 2 of the present invention.

[0025] The realization of the purpose, functional features and advantages of this application will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0026] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of the embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0027] It should be understood that, when used in this specification and the appended claims, the terms "comprising" and "including" indicate the presence of the described features, integrals, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integrals, steps, operations, elements, components and / or collections thereof.

[0028] It should also be understood that the terminology used in this specification is for the purpose of describing particular embodiments only and is not intended to limit the scope of the application. As used in this specification and the appended claims, the singular forms “a,” “an,” and “the” are intended to include the plural forms unless the context clearly indicates otherwise. Those skilled in the art will be able to understand the specific meaning of the above terms in this application according to the specific circumstances.

[0029] In existing methods for preparing binary compounds, a two-dimensional Pd (palladium) thin film is first grown on a substrate, and then a palladium telluride thin film is formed on the substrate by chemical vapor deposition using elemental Te (tellurium) as the tellurium source. However, according to the phase diagram, PdTe2 is the material with the highest Te content in the Pd-Te phase, while other phases, such as Pd9Te4 and Pd... 20 The Pd / Te ratios of Te7 and PdTe are all lower than those of PdTe2, and the formation temperatures of the Pd-Te phases are very close, making it difficult to achieve controlled phase growth by simply controlling the temperature. Therefore, how to control the participation of trace amounts of Te in the reaction to obtain other phases has become an urgent technical problem to be solved.

[0030] Example 1

[0031] Therefore, refer to Figure 1 and Figure 2 This application provides a method for preparing a binary compound, comprising:

[0032] Step S1: Form a first thin film 102 and a second thin film 103 on the substrate 101;

[0033] Step S2: The first thin film 102 and the second thin film 103 are used to generate binary compound films with different phase ratios by chemical vapor deposition.

[0034] In step S1, the amount of the first film 102 and the second film 103 is controlled by the thickness of the first film 102 and the second film 103; in step S2, the generation of binary compounds with different phase ratios is controlled by controlling the thickness ratio of the first film 102 and the second film 103.

[0035] Specifically, as shown in Figure 2, when the first thin film 102 and the second thin film 103 are formed on the substrate 101, the surface areas of the first thin film 102 and the second thin film 103 covering the substrate 101 are equal. Therefore, the preparation method of this application embodiment can control the content of the first thin film 102 and the second thin film 103 respectively by controlling the thickness of the first thin film 102 and the second thin film 103. The surface areas of the first thin film 102 and the second thin film 103 covering the substrate 101 can be set according to specific requirements.

[0036] As can be seen from the phase diagram, the formation temperatures of different phases of binary compounds are very close, making it difficult to achieve controllable phase growth by controlling the temperature alone. However, in some embodiments of this application, the content of the two elements participating in the reaction can be controlled by controlling the thickness of the first thin film 102 and the second thin film 103, thereby controlling the formation of binary compounds with different phases. In other words, the binary compound preparation method according to the embodiments of this application can achieve large-area controllable phase transition of two-dimensional binary compounds.

[0037] The binary compounds mentioned above are usually transition metal sulfides (TMDs), which have a layered structure similar to the single-atom-layer structure of graphene. They consist of two layers of chalcogen atoms sandwiching a layer of transition metal atoms, forming a sandwich-like (XMX) layered structure. The chemical formula of TMDs is MX2, where M refers to the transition metal element and X represents a chalcogen element (such as O, S, Se, and Te).

[0038] It should be noted that the stacking order of the first film 102 and the second film 103 does not affect the preparation of the binary compound. That is, the first film 102 can be placed on top of the second film 103 or below the second film 103.

[0039] Further, step S1 includes: forming a first thin film 102 and a second thin film 103 on the substrate 101 by magnetron sputtering. The magnetron sputtering method utilizes the interaction of a magnetic field and an electric field to cause electrons to move in a spiral pattern near the target surface, thereby increasing the probability of electrons colliding with argon gas to generate ions. The generated ions then collide with the target surface under the influence of the electric field, thus sputtering the target material. In some embodiments of this application, forming the first thin film 102 by magnetron sputtering has advantages such as simple equipment, ease of control, large coating area, and strong adhesion.

[0040] Furthermore, step S1 includes: forming a first thin film 102 and a second thin film 103 on the substrate 101 using electron beam evaporation deposition. Electron beam evaporation deposition is a vacuum deposition method that solves the problem of easy mixing between the film material and the evaporation source material in resistance heating methods. The evaporation material is heated by an electron beam, causing it to vaporize and be transported to the substrate, where it condenses to form a thin film. In some embodiments of this application, forming the first thin film 102 using electron beam evaporation deposition has the advantages of providing higher heat to the material to be evaporated, resulting in a faster deposition rate, accurate electron beam positioning, and avoiding evaporation and contamination of the crucible material.

[0041] In some embodiments according to this application, step S2 includes: placing the substrate 101 on which the first thin film 102 and the second thin film 103 are grown into a quartz boat, and then placing the quartz boat into a tube furnace for chemical vapor deposition. The tube furnace is usually an atmospheric pressure tube furnace; therefore, the method described above for generating binary compounds is simple to operate and has low production costs.

[0042] The substrate 101 includes a conductive layer and an insulating layer, with the conductive layer disposed above the insulating layer. The substrate 101 is the bottom material of all semiconductor chips, primarily serving as physical support, thermal conductivity, and electrical conductivity. The mechanical support structure of the chip module needs to withstand different operating environments and requires sufficient thermal conductivity to quickly dissipate the heat generated by the chip. Simultaneously, the substrate 101 provides electrical conductivity in specific operating environments. Therefore, through the aforementioned configuration, the substrate 101 achieves its functions of physical support, thermal conductivity, and electrical conductivity.

[0043] Furthermore, in some embodiments of this application, the first thin film 102 is a Te thin film, and the second thin film 103 is a Pd thin film. Therefore, in some embodiments of this application, by controlling the thickness of the Te and Pd thin films to control the content of the two elements participating in the reaction, the generation of binary compounds with different phases can be controlled. That is, the binary compound preparation method according to the embodiments of this application can achieve large-area controllable phase transition of two-dimensional binary compounds.

[0044] Specifically, experimental data show that, for example, when the Pd film thickness on substrate 101 is 10 nm, the Te film thickness is 18 nm, and the Pd film is located above the Te film, the resulting binary compound is PdTe; when the Pd film thickness on substrate 101 is 20 nm, the Te film thickness is 42 nm, and the Pd film is located above the Te film, the resulting binary compound is also PdTe; when the Pd film thickness on substrate 101 is 10 nm, the Te film thickness is 42 nm, and the Pd film is located above the Te film, the resulting binary compound is PdTe2; and when the Pd film thickness on substrate 101 is 20 nm, the Te film thickness is 12 nm, and the Pd film is located above or below the Te film, the resulting binary compound is PdTe2. 20 Te7.

[0045] The above data are for illustrative purposes only. In some embodiments of this application, the content of the two elements participating in the reaction can be controlled by controlling the thickness of the Te film and Pd film, thereby controlling the generation of binary compounds with different phases. In other words, the binary compound preparation method according to the embodiments of this application can realize large-area controllable phase transition of two-dimensional binary compounds.

[0046] Furthermore, the first film is a Te film, and the second film is a Mo (molybdenum) film. Therefore, in some embodiments according to this application, by controlling the thickness of the Te film and the Mo film to control the content of the two elements participating in the reaction, the generation of binary compounds with different phases can be controlled. That is, the preparation method of binary compounds according to the embodiments of this application can realize large-area controllable phase transition of two-dimensional binary compounds.

[0047] Furthermore, the first film is a Se (selenium) film, and the second film is a Pd film. Therefore, in some embodiments according to this application, by controlling the thickness of the Te and Se films to control the content of the two elements participating in the reaction, the generation of binary compounds with different phases can be controlled. That is, the preparation method of binary compounds according to the embodiments of this application can realize large-area controllable phase transition of two-dimensional binary compounds.

[0048] Furthermore, substrate 101 is a silicon / silicon oxide substrate. Substrate 101 is the bottom material for all semiconductor chips, mainly serving as a physical support, thermal conductivity, and electrical conductivity. The environmental tolerance, thermal conductivity, and electrical conductivity of the silicon / silicon oxide substrate can well meet the operational requirements.

[0049] Example 2

[0050] Reference Figure 3 The diagram shows a simulated reaction of the preparation method of the binary compound according to Example 2 of this application. The difference from Example 1 is that... Figure 3 The substrate 201 includes a first substrate 21 and a second substrate 22. Step S1 includes: forming a first thin film 202 on the first substrate 21 and forming a second thin film 203 on the second substrate 22. Step S2 includes: placing the first thin film 202 formed on the first substrate 21 above the second thin film 203 formed on the second substrate 22. The first thin film 202 and the second thin film 203 are used to form binary compounds with different phase ratios by chemical vapor deposition.

[0051] Specifically, compared with Embodiment 1, in this embodiment of the application, by generating the first thin film 202 and the second thin film 203 on different substrates 21 and 22, it is possible to avoid mutual interference during the generation of the two films, which would affect the subsequent chemical vapor deposition reaction, thereby facilitating the generation of binary compounds with different phase ratios.

[0052] Specifically, as shown in Figure 3, a first thin film 202 is formed on a first substrate 21, and a second thin film 203 is formed on a second substrate 22. The surface areas of the first thin film 202 and the second thin film 203 covering the substrates 21 and 22 are equal, respectively. Therefore, the preparation method of this embodiment can control the content of the first thin film 202 and the second thin film 203 by controlling their thicknesses. The surface areas of the first thin film 202 and the second thin film 203 covering the substrate 200 can be set according to specific requirements.

[0053] As can be seen from the phase diagram, the formation temperatures of different phases of binary compounds are very close, making it difficult to achieve controllable phase growth by controlling the temperature alone. However, in some embodiments of this application, the content of the two elements participating in the reaction can be controlled by controlling the thickness of the first thin film 202 and the second thin film 203, thereby controlling the formation of binary compounds with different phases. In other words, the binary compound preparation method according to the embodiments of this application can achieve large-area controllable phase transition of two-dimensional binary compounds.

[0054] For example, the thin film formed on the first substrate 21 is a Te thin film 202, and the thin film formed on the second substrate 22 is a Pd thin film 203. The Te thin film 202 is disposed above the Pd thin film 203. When the thickness of the Pd thin film is 20 nm and the thickness of the Te thin film is 30 nm, the resulting binary compound is Pd9Te4.

[0055] The above data are for illustrative purposes only. In some embodiments of this application, the content of the two elements participating in the reaction can be controlled by controlling the thickness of the Te film and Pd film, thereby controlling the generation of binary compounds with different phases. In other words, the binary compound preparation method according to the embodiments of this application can realize large-area controllable phase transition of two-dimensional binary compounds.

[0056] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in this application, and these modifications or substitutions should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A method for preparing a binary compound, characterized in that, include: Step S1: Sequentially form a first thin film and a second thin film on the substrate; Step S2: The first film and the second film are subjected to chemical vapor deposition to generate binary compounds with different phase ratios. In step S1, the content of the first film and the second film is controlled by the thickness of the first film and the second film. In step S2, the generation of the binary compound with different phase ratios is controlled by controlling the thickness ratio of the first film and the second film. The first film is a Te film and the second film is a Pd film, or the first film is a Te film and the second film is a Mo film, or the first film is a Se film and the second film is a Pd film.

2. The method as described in claim 1, characterized in that, Step S1 includes: generating the first thin film and the second thin film on the substrate by magnetron sputtering.

3. The method as described in claim 1, characterized in that, Step S1 includes: generating the first thin film and the second thin film on the substrate by electron beam evaporation deposition.

4. The method according to any one of claims 1 to 3, characterized in that, Step S2 includes: placing the substrate on which the first and second films are grown into a quartz boat, and then placing the quartz boat into a tube furnace for chemical vapor deposition.

5. The method as described in claim 4, characterized in that, The substrate includes a first substrate and a second substrate. Step S1 includes: generating the first thin film on the first substrate and generating the second thin film on the second substrate. Step S2 includes: placing the first thin film generated on the first substrate above the second thin film generated on the second substrate. The first thin film and the second thin film are used to generate the binary compound with different phase ratios by chemical vapor deposition.

6. The method as described in claim 5, characterized in that, The substrate includes a conductive layer and an insulating layer, with the conductive layer disposed above the insulating layer.

7. The method as described in claim 6, characterized in that, The substrate is a silicon / silicon oxide substrate.

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