阅读说明：本技术 一种改变硒化锑薄膜电学性质的方法及硒化锑太阳电池 (Method for changing electrical properties of antimony selenide film and antimony selenide solar cell ) 是由 李志强 郭春升 梁晓杨 于 2019-11-28 设计创作，主要内容包括：本发明提供了一种改变硒化锑薄膜电学性质的方法及硒化锑太阳电池,所述方法为通过磁控溅射法或热蒸发镀膜法在衬底上沉积一层金属层,然后利用近空间升华法在所述金属层上进行硒化锑的沉积,在沉积硒化锑时,调控衬底的温度在250~450℃,使金属层中的金属元素向硒化锑层扩散,从而形成硒化锑合金薄膜,实现对硒化锑薄膜电学性质的优化。本发明在薄膜沉积过程中,通过调控衬底温度,来制得结晶情况更优、缺陷密度更小、载流子浓度高的硒化锑合金薄膜,且该工艺方法操作简单,条件可控,其电学性质可调,适宜进一步推广与应用。(The invention provides a method for changing the electrical property of an antimony selenide film and an antimony selenide solar cell, wherein the method comprises the steps of depositing a metal layer on a substrate by a magnetron sputtering method or a thermal evaporation coating method, then depositing antimony selenide on the metal layer by a close-space sublimation method, and regulating the temperature of the substrate to be 250-450 ℃ when depositing antimony selenide, so that metal elements in the metal layer are diffused to the antimony selenide layer, thereby forming an antimony selenide alloy film and realizing the optimization of the electrical property of the antimony selenide film. In the film deposition process, the antimony selenide alloy film with better crystallization condition, smaller defect density and high carrier concentration is prepared by regulating and controlling the substrate temperature, and the process method has the advantages of simple operation, controllable conditions and adjustable electrical properties, and is suitable for further popularization and application.)

1. A method for changing the electrical properties of an antimony selenide film is characterized in that a metal layer is deposited on a substrate through a magnetron sputtering method or a thermal evaporation coating method, then antimony selenide is deposited on the metal layer through a near space sublimation method, and when antimony selenide is deposited, the temperature of the substrate is regulated to 250-450 ℃, so that metal elements in the metal layer diffuse to the antimony selenide layer, the antimony selenide alloy film is formed, and the optimization of the electrical properties of the antimony selenide film is realized.

2. The method of claim 1, wherein the antimony selenide thin film comprises (Sb)₂Se₃)_x(ASbSe₂)_1-xWherein A represents Cu or Ag, and 0 < x < 1.

3. The method of claim 1, wherein the substrate is a glass or FTO with a molybdenum back electrode deposited thereon.

4. The method for changing the electrical properties of the antimony selenide film as claimed in claim 1, wherein the near space sublimation method is carried out under the condition that the high-purity solid antimony selenide particles are ground into powder to prepare an evaporation source, and the temperature of the evaporation source is 400-550 ℃.

5. The method of claim 1, wherein the thickness of the metal layer deposited on the substrate by magnetron sputtering or thermal evaporation coating is 1-10 nm.

6. An antimony selenide solar cell, comprising the antimony selenide alloy thin film prepared by the method of any one of claims 1 to 5.

7. The antimony selenide solar cell according to claim 6, wherein the solar cell sequentially comprises a glass substrate, a molybdenum electrode layer, an antimony selenide alloy thin film layer, a cadmium sulfide layer, a zinc oxide layer, an aluminum-doped zinc oxide layer and a gold electrode layer from bottom to top.

Technical Field

The invention relates to the technical field of semiconductor film preparation, in particular to a method for changing the electrical property of an antimony selenide film and an antimony selenide solar cell.

Background

Antimony selenide (Sb)₂Se₃) Due to the appropriate band gap (1.1-1.3 eV), high absorption coefficient (10)⁵cm^-1) Low cost, no toxicity and the like, and is considered to be a promising absorption material of the thio compound photovoltaic device. Antimony selenide has a one-dimensional crystal structure and anisotropic optoelectronic properties that are of great interest.

The film forming quality of the absorption layer of the solar cell device based on the antimony selenide thin film is crucial to the performance of the device, and determines the highest efficiency which can be achieved by the device. One way to obtain a high quality antimony selenide absorber layer is to reduce the intrinsic point defects in antimony selenide and extend the lifetime of the electron carriers (antimony selenide carrier concentration of 10)¹³-10¹⁴cm^-3). At present, the preparation process of the high-efficiency antimony selenide solar cell in each laboratory mainly comprises three steps: 1) by carrying out post-selenization treatment on antimony selenide, the selenium vacancy defect of an antimony selenide absorption layer in the thermal evaporation process is compensated, and the recombination loss in the device is reduced; 2) the antimony selenide film is deposited in a selenium-rich environment, so that a long carrier life and low interface defect and bulk defect films can be obtained; 3) the vapor deposition (VTD) technology is adopted to prepare the antimony selenide absorption layer, so that the density of main defects can be reduced by 1 order of magnitude. However, the open circuit voltage (Voc) of these high efficiency antimony selenide solar cells is in the range of 350-420mV, with low Voc still limiting Sb₂Se₃The main impediment to device performance. In addition, calculation by the first principle shows that Sb₂Se₃The intrinsic point defects of (a) are forced by their low symmetry, and it is difficult to suppress the formation of these deep complex defects merely by controlling the growth environment. Therefore, a method for changing the electrical property of antimony selenide is soughtAnd further, the solar cell device with high open-circuit voltage and high efficiency has important research significance.

Disclosure of Invention

The invention aims to provide a method for changing the electrical property of an antimony selenide film and an antimony selenide solar cell, and aims to solve the problems that the current carrier concentration of the existing antimony selenide solar cell is low, and the existing method is difficult to inhibit the formation of the deep recombination defect of the antimony selenide film.

The purpose of the invention is realized by the following technical scheme: a method for changing the electrical properties of an antimony selenide film comprises the steps of depositing a metal layer on a substrate through a magnetron sputtering method or a thermal evaporation coating method, then depositing antimony selenide on the metal layer through a near space sublimation method, regulating the temperature of the substrate to be 250-450 ℃ when depositing antimony selenide, and enabling metal elements in the metal layer to diffuse towards the antimony selenide layer, so that an antimony selenide alloy film is formed, and optimization of the electrical properties of the antimony selenide film is achieved.

The antimony selenide alloy thin film is (Sb)₂Se₃)_x(ASbSe₂)_1-xWherein A represents Cu or Ag, and 0 < x < 1.

The substrate is glass or FTO deposited with a molybdenum back electrode.

The near-space sublimation method is characterized in that high-purity solid antimony selenide particles are ground into powder to prepare an evaporation source, and the temperature of the evaporation source is 400-550 ℃.

The thickness of the metal layer deposited on the substrate by the magnetron sputtering method or the thermal evaporation coating method is 1-10 nm.

An antimony selenide solar cell comprises the antimony selenide alloy thin film prepared by the method.

The solar cell sequentially comprises a glass substrate, a molybdenum electrode layer, an antimony selenide alloy film layer, a cadmium sulfide layer, a zinc oxide layer, an aluminum-doped zinc oxide layer and a gold electrode layer from bottom to top.

In the film deposition process, the antimony selenide alloy film with better crystallization condition, smaller defect density and high carrier concentration is prepared by regulating and controlling the substrate temperature, and the process method has the advantages of simple operation, controllable conditions and adjustable electrical properties, and is suitable for further popularization and application.

The low carrier concentration is one of the key factors for limiting the open-circuit voltage of an antimony selenide device, namely the antimony-based ternary compound (CuSbSe) of the invention₂、AgSbSe₂) Has rock salt crystal structure, and its electric properties are influenced by atom arrangement, so that its carrier concentration can be up to 10^18-19cm^-3. Compared with the prior art, the invention has the advantages that:

1) the preparation method is simple, and the substrate temperature can be accurately regulated and controlled in the preparation process; 2) the preparation process is pollution-free, and no toxic product is generated; 3) the antimony selenide film is prepared by adopting Close Space Sublimation (CSS), the adopted source is antimony selenide powder, the deposition rate is adjustable, and the material is saved; 4) the thickness of the deposited metal layer and the diffusion amount of the metal layer to the antimony selenide layer can be accurately controlled through the substrate temperature and the deposition time, and further the electrical property of the antimony selenide can be optimized and regulated.

Drawings

FIG. 1 shows (Sb)₂Se₃)_x(AgSbSe₂)_1-xXRD test pattern of the alloy film.

FIG. 2 shows (Sb)₂Se₃)_x(AgSbSe₂)_1-xHall test pattern of the alloy film.

FIG. 3 is (Sb)₂Se₃)_x(CuSbSe₂)_1-xXRD test pattern of the alloy film.

Fig. 4 is a schematic structural diagram of the prepared alloy thin film solar cell. In the figure, 1 is a glass substrate, 2 is a molybdenum electrode layer, 3 is an antimony selenide alloy thin film layer, 4 is a cadmium sulfide layer, 5 is a zinc oxide layer, 6 is an aluminum-doped zinc oxide layer, and 7 is a silver electrode layer.

FIG. 5 is an I-V diagram of the prepared alloy thin film solar cell.

Detailed Description

The present invention will be described in detail with reference to specific examples.