Method for preparing cubic boron nitride thin film

Abstract

A method for preparing a cubic boron nitride thin film belongs to the field of wide band gap semiconductor or superhard material thin film. The direct preparation of boron nitride films with high cubic phase content is difficult to control and has poor repeatability; during the nucleation and growth of cubic boron nitride films, energetic particles must bombard the surface of the film, which will cause structural defects in the film and residual stress in the film. If it is too large, it is easy to crack and fall off. Steps of the present invention: after the substrate is cleaned, a hexagonal boron nitride film is deposited on the substrate material using vapor phase film growth equipment; the vacuum degree is pumped below 5 Pa, and the hexagonal boron nitride film is annealed with nitrogen protection: the annealing temperature is 850- 950°C, constant temperature for 20-60 minutes; the nitrogen gas is above 99.999% pure. The present invention has loose conditions and good repeatability: no need to install a substrate heating device and a substrate negative bias device to generate energy particles to bombard the film; no need to select the best working gas pressure and composition; and the hexagonal boron nitride film The deposition rate is faster, and it is not easy to crack and fall off.

Description

technical field

[0001] The invention relates to a method for preparing a cubic boron nitride thin film by combining vapor deposition and annealing technology. The invention belongs to the field of wide bandgap semiconductor or superhard material film preparation. Background technique

[0002] Boron nitride (BN) is a new wide bandgap semiconductor material. In the boron nitride system, hexagonal boron nitride (h-BN) and cubic boron nitride (c-BN) are the two stable main phases. Among them, cubic boron nitride has outstanding physical, chemical and mechanical properties. Therefore, the research on its material preparation and characteristics, as well as the exploration of industrialization and deviceization have been the research topics of scientific researchers in various countries and well-known semiconductor companies such as US G.E., IBM, and British DeBeers in recent years.

[0003] The hardness and thermal conductivity of cubic boron nitride are second only to diamond...