A method for preparing boron carbide coating by plasma spraying

Abstract

The invention provides a method for preparing a boron carbide coating through plasma spraying. The method comprises the steps that: step (1), boron carbide powder and carbon powder are uniformly mixed; and the mixed powder is delivered into a plasma spraying device; step (2) the surface of a substrate requiring spraying is pretreated; step (3) plasma spraying is carried out on the surface of the substrate by using the plasma spraying device, such that the boron carbide coating is prepared. According to the invention, the coating is prepared through a carbon-doped B4C powder plasma spraying method. When jet flow is ejected, graphite powder take the priority to react with oxygen, such that B4C oxidation is avoided; with the addition of carbon, B4C high-temperature decomposition is inhibited, such that B4C loss under high temperature can be reduced or even prevented, and B4C coating with good performance can be obtained; with carbon doping, no impurity element is introduced into the coating, such that coating quality is ensured; also, with the addition of graphite powder, powder fluidity is increased, and spraying is facilitated.

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 plasma spraying. Background technique [0002] Plasma etching is an indispensable technology in semiconductor manufacturing process, microelectronic IC manufacturing process and micro-nano manufacturing process. , which uses glow discharge to generate plasma containing charged particles such as plasma and electrons and highly chemically active neutral atoms, molecules and free radicals for pattern transfer. An irreplaceable process from photolithographic template transfer to silicon wafers. In the VLSI manufacturing process, nearly one-third of the processes are completed by means of plasma processing, such as plasma thin film deposition, plasma etching and plasma deglue. [0003] During the plasma dry etching process, a large amount of active free radicals such as Cl radicals and F radicals will be generated. When they...

AI Technical Summary

Problems solved by technology

[0004] With the development of thermal spraying technology, spraying pure Al on aluminum substrate 2 o 3 The ceramic coating effectively solves the corrosion problem of the etching process chamber under low-power plasma, but with the increase of the wafer size, the inner diameter of the plasma etching process chamber has increased from 400mm to 500-600mm, and the corresponding plasma etching process The power is also increasing, and the corrosion of the plasma on the etching process chamber wall is also increasing, making the following problems prone to occur during the etching process: (1) particles; (2) peeling off of the process chamber wall, resulting in The plasma directly interacts with the aluminum substrate; (3) Al 2 o 3 Component life limited by higher power

[0010] 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