A group iv-vi semiconductor thin film and a method for producing the same

Abstract

The application provides a group IV-VI semiconductor thin film and a preparation method thereof. A is dissolved in an organic polar solvent to form a first solution, B is dissolved in an organic polar solvent to form a second solution, the first solution and the second solution are mixed to obtain a precursor solution, or A and B are mixed and then dissolved in an organic polar solvent to obtain a precursor solution, A is a group IV compound, and B is a group VI compound; a substrate is placed in the precursor solution, thin film growth is carried out at a first temperature through a chemical bath deposition reaction process, and the semiconductor thin film with a required thickness is obtained. The substrate is directly placed in the solution of the group IV compound and the group VI compound, and the semiconductor thin film can be grown at a suitable temperature; compared with a thin film synthesized through a solution chemical in-situ reaction, the process is simple and convenient, and the semiconductor thin film can be prepared in a large area.

Description

Technical Field

[0001] This invention relates to the field of semiconductor thin film preparation, and more particularly to a group IV-VI semiconductor thin film and its preparation method. Background Technology

[0002] Group IV-VI semiconductors have narrow direct bandgap energies and large exciton Bohr radii, and are widely used in military, remote sensing and other fields.

[0003] Lead salt semiconductors such as PbS, PbSe, and PbTe are used as windows for infrared detectors in single-crystal or polycrystalline form, and more recently they have been used as materials for infrared emitters and solar energy controllers. They have potential applications in photonic switches, thermal and biological imaging, optoelectronic devices, solar cells, and high-efficiency photovoltaic conversion.

[0004] Methods for preparing group IV-VI semiconductor thin films include physical and chemical methods. Physical methods mainly utilize electrical energy to raise the temperature, causing the material to evaporate, or the energy of high-energy particles such as electrons, ions, and photons to sputter the target material, forming the desired thin film on the substrate. Examples include vacuum evaporation and magnetron sputtering.

[0005] Chemical methods mainly include: chemical bath deposition, continuous ion layer adsorption reaction, and solution chemical in-situ reaction.

[0006] Chemical bath deposition is a method of depositing thin films through chemical reactions. A pretreated substrate is immersed in a solution containing metal ions, anions, and other functional reagents, and a semiconductor thin film is obtained through heterogeneous chemical deposition. However, this method involves homogeneous precipitation during the heterogeneous deposition process, resulting in significant material loss.

[0007] The continuous ion-layer adsorption (ILA) reaction method employs an independent ion precursor solution and utilizes ion adsorption on the substrate surface to prepare thin films through a cyclical process of layer-by-layer adsorption interface deposition, thus preventing the formation of homogeneous reaction precipitates in the solution. This method yields thin films with good uniformity and high density, and can be deposited over large areas, but the growth rate is slow and the preparation process is complex.

[0008] Solution chemistry in-situ reaction is a chemical film formation technique developed based on continuous ion layer adsorption reaction. First, a lead-based precursor film is pre-prepared on a substrate, and then the reaction occurs in a sulfur-based reaction solution to obtain the deposited film. This method is complex, time-consuming, and labor-intensive.

[0009] Organic solvent chemical deposition (OSC) operates on a principle similar to chemical bath deposition, but its solution preparation is simpler, eliminating the need for pH adjustment, and the solution can be stored at low temperatures for extended periods. The deposited films exhibit high-quality grains and good crystallinity. Film growth is rapid, with almost all material deposited on the substrate, resulting in minimal material loss. The film fabrication process is simple, allowing for large-area fabrication, which is beneficial for industrialization. Summary of the Invention

[0010] Based on the problems existing in the prior art, the present invention aims to provide a method for preparing group IV-VI semiconductor thin films by organic solvent chemical deposition. This method involves directly placing the substrate in a solution of group IV or group VI compounds, and growing the semiconductor thin film at a suitable temperature. Compared with thin films synthesized by solution chemical in-situ reaction, this method is simple, convenient, and can prepare semiconductor thin films on a large area.

[0011] This invention provides a method for preparing a group IV-VI semiconductor thin film, comprising:

[0012] A is dissolved in an organic polar solvent to form a first solution, and B is dissolved in an organic polar solvent to form a second solution. The first and second solutions are mixed to obtain a precursor solution, or A and B are mixed and dissolved in an organic polar solvent to obtain a precursor solution. A is a group IV compound and B is a group VI compound.

[0013] The substrate is placed in the precursor solution, and a thin film is grown at a first temperature through a chemical bath deposition process to obtain the semiconductor thin film of the desired thickness.

[0014] Furthermore, the substrate is glass, quartz, fluorine-doped indium oxide, indium oxide, sapphire, or calcium fluoride.

[0015] Furthermore, the organic polar solvent is methanol, formamide, ethanol, acetonitrile, N-methylformamide, N,N-dimethylformamide, dimethyl sulfoxide, or carbon disulfide.

[0016] Furthermore, the group IV compound is a nitrate, acetate, halide, or halogenate.

[0017] Further, the group VI compounds are thiourea and its derivatives, selenourea and its derivatives, tellurium and its derivatives, thiols, thiophenols, thioethers, dithioethers, selenools, selenophenols, selenoethers, diselenoethers, sulfides, or selenides.

[0018] Furthermore, the concentration of A in the first solution and the concentration of B in the second solution have the same range. Preferably, the concentration of A in the first solution is 0.005-0.1 mol / L, and the concentration of B in the second solution is 0.005-0.1 mol / L.

[0019] Furthermore, the first temperature range is 15-100℃, and the film growth time is 2-24 hours.

[0020] Furthermore, before immersing the substrate in the precursor solution, the substrate is dried using gas, and a sealing layer is attached to the back of the substrate. Preferably, the gas is nitrogen, and the sealing layer is adhesive tape or a glass strip.

[0021] The present invention also provides a group IV-VI semiconductor thin film, wherein the group IV-VI semiconductor thin film is prepared by the method described in any of the preceding claims.

[0022] Beneficial Effects: This invention provides a group IV-VI semiconductor thin film and its preparation method. A is dissolved in an organic polar solvent to form a first solution, and B is dissolved in an organic polar solvent to form a second solution. The first and second solutions are mixed to obtain a precursor solution, or A and B are mixed and dissolved in an organic polar solvent to obtain a precursor solution. A is a group IV compound, and B is a group VI compound. A substrate is placed in the precursor solution, and thin film growth is carried out at a first temperature through a chemical bath deposition reaction process to obtain the semiconductor thin film of the desired thickness. This invention directly places the substrate in a solution of group IV or group VI compounds, and semiconductor thin films can be grown at a suitable temperature. Compared with thin films synthesized by in-situ chemical reactions in solution, the process is simple, convenient, and allows for large-area preparation of semiconductor thin films. Attached Figure Description

[0023] To more clearly illustrate the technical solutions in the embodiments or prior art, the drawings used in the description of the embodiments or prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0024] Figure 1 This is a scanning electron microscope image of the PbS thin film of Embodiment 1 of the present invention;

[0025] Figure 2 This is a scanning electron microscope image of the PbS thin film in Embodiment 2 of the present invention;

[0026] Figure 3 This is a scanning electron microscope image of the PbS thin film in Embodiment 3 of the present invention;

[0027] Figure 4 This is a scanning electron microscope image of the PbS thin film in Embodiment 4 of the present invention;

[0028] Figure 5 This is a scanning electron microscope image of the PbS thin film of Embodiment 5 of the present invention;

[0029] Figure 6 This is a scanning electron microscope image of the PbS thin film of Embodiment 6 of the present invention;

[0030] Figure 7 This is a scanning electron microscope image of the PbS thin film of Embodiment 7 of the present invention;

[0031] Figure 8 This is an X-ray diffraction pattern of the PbS thin film according to an embodiment of the present invention;

[0032] Figure 9 This is an X-ray diffraction pattern of the PbS thin film according to an embodiment of the present invention. Detailed Implementation

[0033] The following descriptions of the embodiments are made with reference to the accompanying illustrations to illustrate specific embodiments in which the invention can be implemented.

[0034] This invention provides a method for preparing group IV-VI semiconductor thin films, the specific steps of which include:

[0035] (1) Preparation of precursor solution

[0036] A group IV compound is dissolved in an organic polar solvent at a concentration ranging from 0.005 to 0.1 mol / L; a group VI compound is then dissolved in an organic polar solvent at a concentration ranging from 0.005 to 0.1 mol / L; wherein the group IV compound is a nitrate, acetate, halide, or halate, etc., and the group VI compound is a thiourea or its derivatives, a selenourea or its derivatives, a tellurium or its derivatives, a thiol, a thiophenol, a thioether, a disulfide, a selenool, a selenophenol, a selenoether, a diselenoether, a sulfide, or a selenide, etc., and the organic polar solvent is methanol, formamide, ethanol, acetonitrile, N-methylformamide, N,N-dimethylformamide, dimethyl sulfoxide, or carbon disulfide, etc.

[0037] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0038] The substrate is ultrasonicated for 30 minutes each with a detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. The substrate is then placed in a mixed solvent of group IV and group VI compounds and grown at a temperature of 15-100°C for 2-24 hours to obtain a PbS film of the desired thickness. The substrate can be glass, quartz, fluorine-doped indium oxide, indium oxide, sapphire, or calcium fluoride, etc.

[0039] It should be noted that there are no requirements for the order of mixing group IV and group VI compounds and adding the substrate. The group IV and group VI compounds can be weighed and dissolved and dispersed together, or they can be dissolved and dispersed separately and then mixed; or the substrate can be added first and then the solution can be added.

[0040] Example 1

[0041] (1) Preparation of precursor solution

[0042] Group IV compounds were dissolved in formamide at a concentration of 0.005 mol / L; then Group VI compounds were dissolved in formamide at a concentration of 0.005 mol / L.

[0043] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0044] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 60°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0045] Example 2

[0046] (1) Preparation of precursor solution

[0047] Group IV compounds were dissolved in formamide at a concentration of 0.03 mol / L; then Group VI compounds were dissolved in formamide at a concentration of 0.03 mol / L.

[0048] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0049] The substrate is ultrasonicated for 30 minutes each with a detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. The substrate is then placed in a mixed solvent of group IV and group VI compounds and grown at 15°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0050] Example 3

[0051] (1) Preparation of precursor solution

[0052] Group IV compounds were dissolved in formamide at a concentration of 0.03 mol / L; then Group VI compounds were dissolved in formamide at a concentration of 0.03 mol / L.

[0053] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0054] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 100°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0055] Example 4

[0056] (1) Preparation of precursor solution

[0057] Group IV compounds were dissolved in formamide at a concentration of 0.1 mol / L; then Group VI compounds were dissolved in formamide at a concentration of 0.1 mol / L.

[0058] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0059] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 60°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0060] Example 5

[0061] (1) Preparation of precursor solution

[0062] Group IV compounds were dissolved in methanol at a concentration of 0.03 mol / L; then Group VI compounds were dissolved in methanol at a concentration of 0.03 mol / L.

[0063] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0064] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 60°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0065] Example 6

[0066] (1) Preparation of precursor solution

[0067] Group IV compounds were dissolved in N-methylformamide at a concentration of 0.03 mol / L; then Group VI compounds were dissolved in N-methylformamide at a concentration of 0.03 mol / L.

[0068] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0069] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 60°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0070] Example 7

[0071] (1) Preparation of precursor solution

[0072] Group IV compounds were dissolved in N,N'-dimethylformamide at a concentration of 0.03 mol / L; then Group VI compounds were dissolved in N,N'-dimethylformamide at a concentration of 0.03 mol / L.

[0073] (2) Preparation of PbS thin films by organic solvent chemical bath deposition

[0074] The substrate is ultrasonicated for 30 minutes each with detergent solution, isopropanol, and ethanol, and then stored in ethanol for later use. Before use, the solvent on the substrate is dried with a nitrogen gun. Adhesive tape or other materials such as glass strips can be applied to the back of the substrate to prevent film growth on the back side. Then, the substrate is placed in a mixed solvent of group IV and group VI compounds and grown at 60°C for 2-24 hours to obtain a PbS film of the desired thickness.

[0075] In summary, this invention provides a group IV-VI semiconductor thin film and its preparation method. A is dissolved in an organic polar solvent to form a first solution, and B is dissolved in an organic polar solvent to form a second solution. The first and second solutions are mixed to obtain a precursor solution, or A and B are mixed and dissolved in an organic polar solvent to obtain a precursor solution. A is a group IV compound, and B is a group VI compound. A substrate is placed in the precursor solution, and thin film growth is performed at a first temperature through a chemical bath deposition process to obtain the semiconductor thin film of the desired thickness. This invention directly places the substrate in a solution of group IV or group VI compounds, and semiconductor thin films can be grown at a suitable temperature. Compared with thin films synthesized by in-situ chemical reactions in solution, the process is simple, convenient, and allows for large-area preparation of semiconductor thin films.

[0076] It should be noted that although the present invention has been disclosed above with specific embodiments, the above embodiments are not intended to limit the present invention. Those skilled in the art can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be determined by the scope defined in the claims.

Claims

1. A method for preparing a group IV-VI semiconductor thin film, characterized in that, include: A is dissolved in an organic polar solvent to form a first solution, and B is dissolved in an organic polar solvent to form a second solution. The first and second solutions are mixed to obtain a precursor solution, or A and B are mixed and dissolved in an organic polar solvent to obtain a precursor solution. A is a group IV compound and B is a group VI compound. The substrate is placed in the precursor solution, and a thin film is grown at a first temperature through a chemical bath deposition reaction process to obtain the semiconductor thin film of the desired thickness. The concentration of A in the first solution and the concentration of B in the second solution have the same range, and the concentration of A in the first solution is 0.005-0.1 mol / L. The first temperature range is 15-100℃, and the film growth time is 2-24 hours; The organic polar solvent is formamide, N-methylformamide, or N,N-dimethylformamide.

2. The method for preparing a group IV-VI semiconductor thin film according to claim 1, characterized in that, The substrate is glass, quartz, fluorine-doped indium oxide, indium oxide, sapphire, or calcium fluoride.

3. The method for preparing a group IV-VI semiconductor thin film according to claim 1, characterized in that, The group IV compounds are nitrates, acetates, halides, or halates.

4. The method for preparing a group IV-VI semiconductor thin film according to claim 1, characterized in that, The group VI compounds are thiourea and its derivatives, selenourea and its derivatives, tellurium and its derivatives, thiols, thiophenols, thioethers, disulfides, selenools, selenophenols, selenoethers, diselenoethers, sulfides, or selenides.

5. A group IV-VI semiconductor thin film, characterized in that, The group IV-VI semiconductor thin film is prepared by the method described in any one of claims 1-4.

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