Plasma Etching Method

摘要

An object of the present invention is to provide a plasma etching method capable of forming a tapered recess portion in a wide-gap semiconductor substrate. As a solving means therefor, a high speed etching film E an etching speed of which is higher than that of a wide-gap semiconductor substrate K is formed on the wide-gap semiconductor substrate K, and a mask M having an opening is formed on the high speed etching film E. Thereafter, the wide-gap semiconductor substrate K having the high speed etching film E and the mask M formed thereon is placed on a platen and is heated to a temperature equal to or higher than 200° C., then a plasma is generated form an etching gas supplied into a processing chamber and a bias potential is applied to the platen, and thereby the wide-gap semiconductor substrate K is etched.

主权项

1. A plasma etching method of plasma etching a wide-gap semiconductor substrate placed on a platen arranged in a processing chamber using a plasma generated from a reactive etching gas, comprising;
a deposition step of forming a high speed etching film on a surface of the wide-gap semiconductor substrate, the high speed etching film comprising a component which is etched at a higher speed than a component of the wide-gap semiconductor substrate by reactive species generated by generating the plasma from the reactive etching gas, a mask forming step of forming a mask having an opening on the high speed etching film formed on the surface of the wide-gap semiconductor substrate; and an etching step of placing the wide-gap semiconductor substrate on the platen arranged in the processing chamber, heating the wide-gap semiconductor substrate to a temperature equal to or higher than 200° C., and supplying the reactive etching gas into the processing chamber to generate the plasma and applying a bias potential to the platen on which the wide-gap semiconductor substrate is placed, thereby etching, through the opening, the high speed etching film and the wide-gap semiconductor substrate by the plasma generated from the reactive etching gas.