Method for inducing crystallization of amorphous silicon thin film into polycrystalline silicon thin film by aluminum at low temperature

Abstract

The invention relates to a method for inducing crystallization of an amorphous silicon thin film into a polycrystalline silicon thin film by aluminum at a low temperature, belonging to the technical field of preparation of the polycrystalline silicon thin film. By using the catalytic action of the metal aluminum, the amorphous silicon thin film is induced to be crystallized into the polycrystalline silicon thin film through a two-step annealing method at the low temperature so as to reduce the metal contamination. According to the main technical scheme provided by the invention, the method comprises the steps of: taking glass as a growth substrate and then preparing amorphous silicon, silicon dioxide and aluminum films in sequence to form a multiple-interface structure; then performing two-step annealing, i.e., performing rapid annealing, subsequently placing a sample in an annealing furnace to perform slow annealing, corroding to remove aluminum and drying with nitrogen; and finally, preparing the polycrystalline silicon thin film crystallized under the induction of the aluminum, wherein the grain size is about 50-200 nm. According to the method, the metal contamination in the metal induced crystallization (MIC) technology can be effectively relieved; and the method is suitable for preparing photoelectric devices such as a field effect transistor and a thin film solar cell.

Description

technical field [0001] The invention relates to a preparation method for inducing the crystallization of an amorphous silicon film into a polysilicon film at a low temperature by metal aluminum, which mainly utilizes the catalytic effect of metal aluminum to induce the crystallization of an amorphous silicon film into a polysilicon film at a low temperature, which belongs to polysilicon Thin film preparation technology field. Background technique [0002] At present, the methods for preparing polysilicon thin films mainly include: low pressure chemical vapor deposition (LPCVD), solid phase crystallization (SPC), excimer laser induced crystallization (ELA), rapid thermal annealing crystallization (RTA), etc. [0003] The polysilicon film prepared by LPCVD method is dense and uniform, and can be produced in a large area, but when prepared by this method, the required substrate temperature is high and the deposition speed is slow, and cheap glass cannot be used as the substrate...

AI Technical Summary

Problems solved by technology

Films with different grain sizes can be prepared by controlling the time and temperature of the three stages of heating up, stabilizing, and cooling. The boundary density is large, the material defect density is high, and it is a high-temperature annealing method, which is not suitable for preparing polysilicon with glass as a substrate.

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