Copper-zinc-tin-sulfur-based thin film precursor with cyclic quantum well structure and preparation method of copper-zinc-tin-sulfur-based thin film precursor

Abstract

The invention discloses a copper-zinc-tin-sulfur-based film precursor with a cyclic quantum well structure and a preparation method of the copper-zinc-tin-sulfur-based film precursor, and the preparation method comprises the following steps: accurately weighing the mass of a substrate before and after growth by using a balance, and obtaining the amount of a corresponding precursor growth source substance through molar mass conversion; obtaining the relationship among the growth rate, the film forming thickness and the growth time of the growth source, controlling the proportion of elements of each precursor growth source by controlling the growth time, and performing quantum-well-like growth on the precursor of the copper-zinc-tin-sulfur-based thin film according to the division of the growth time; the invention further discloses a magnetron sputtering, thermal evaporation or electron beam evaporation growth method which has the characteristics of high background vacuum, stable growth rate and high repeatability. Based on the preparation method, the composition and the element ratio of the film and the precursor thereof can be accurately regulated and controlled, and the technical problem that the overall element ratio of an existing copper-zinc-tin-sulfur-based film is unbalanced is solved.

Description

technical field [0001] The invention belongs to the technical field of semiconductor photovoltaic devices, and in particular relates to a copper-zinc-tin-sulfur-based film precursor with a cyclic quantum well structure and a preparation method thereof. Background technique [0002] The combination of renewable energy and Internet technology is the booster of the third industrial revolution. From the perspective of development trend, renewable energy such as wind energy, solar energy and biomass energy is expected to replace fossil energy in 2050; Ten years will still be an important transition period for energy development, and solar energy, as a green renewable energy, is expected to become a new force in it. After more than 10 years of hard work, my country's photovoltaic industry has become one of the strategic emerging industries with international competitiveness. [0003] At present, solar cells for large-scale industrial applications include silicon-based solar cells...

AI Technical Summary

Problems solved by technology

This gap is largely due to the difference between the copper-zinc-tin-sulfur-based thin-film material itself and the CIGS thin-film material. One of the important reasons is that the copper-zinc-tin-sulfur-based thin-film material is very sensitive to its element ratio, and its stable single The phase area is very narrow. In the actual growth process, high-temperature selenization or sulfidation is required, which can easily cause the loss of Sn and Zn elements, or the problem of local element mismatch, and the introduction of Cu 2 S(Se), ZnS(Se), SnS(Se) 2 equal quadratic phase

These secondary phases lead to different degrees of damage to the device performance of solar cells: some of them have better conductivity and narrow band gap (such as Cu 2 The secondary phase of S(Se)) is easy to form internal bulk leakage current due to its high carrier concentration, thereby reducing the working voltage of the battery; while the wide bandgap (such as ZnS(Se), SnS(Se) 2 ) secondary phase may become a recombination center inside the material; a large number of secondary phases can also easily form an insulating layer or a secondary diode, resulting in an increase in the series resistance of the material, making it difficult to export photogenerated electron-hole pairs, thereby reducing the battery output current

Images