A method for preparing boron carbide coating by reactive plasma spraying

Abstract

The invention provides a method for preparing a boron carbide coating through reaction plasma spraying. The method comprises the steps that: step (1), boron carbide powder is selected and is delivered into a plasma spraying device; step (2), the surface of a substrate requiring spraying is pretreated; and step (3), plasma spraying is carried out upon the surface of the substrate by using the reaction plasma spraying device, such that the boron carbide coating is prepared. According to the invention, spraying is carried out by using methane gas (CH4) which is used for replacing hydrogen as an auxiliary working gas. Methane gas has a reducing performance after ionization, such that B4C can be protected from oxidation. Also, the gas comprises C. Through a reaction of C and B4C, C loss of B4C under high temperature can be reduced or even prevented, such that the B4C coating with good performances can be obtained.

Description

technical field [0001] The invention relates to the technical field of plasma spraying, in particular to a method for preparing a boron carbide coating by gas phase reaction plasma spraying. Background technique [0002] At present, the low-temperature plasma microfabrication method is the key technology for micro-nano processing of materials. It is the basis of preparation technologies such as microelectronics, optoelectronics, micromechanics, and micro-optics. One of the processes is completed by means of plasma processing, such as plasma film deposition, plasma etching, and plasma deglue. Among them, plasma etching is one of the most critical processes, and it is an irreplaceable process to realize the high-fidelity transfer of micro-patterns in VLSI production from photolithographic templates to silicon wafers. [0003] During the etching process, due to the existence of a large number of highly corrosive active free radicals, they will also corrode the inner surface of...

AI Technical Summary

Problems solved by technology

Entering the 300mm equipment, as the plasma power increases, the plasma damages the etching process cavity wall more and more, making the following problems prone to occur during the etching process: (1) particles; (2) process The cavity wall coating peels off, causing the plasma to directly interact with the aluminum substrate; (3) Al 2 o 3 Component life limited by higher power

However, B 4 C has problems such as high-temperature oxidation and gasification during the spraying process, and atmospheric plasma spraying cannot prepare B with good performance. 4 C coating

Some studies have adopted a special protection technology to carry out plasma spraying under the protection of inert gas, although it has obtained B 4 C coating, but there is still a small part of oxidation products in the coating