ETCH WITH MIXED MODE PULSING

摘要

Provided is a method for etching a dielectric layer arranged under a patterned organic mask having a feature, and the hard mask of the lower part of an organic mask feature. An etch gas is provided. The etch gas of plasma is formed. A pulsed bias having a pulse frequency of 10 Hz to 1 kHz is provided. A bias RF having a frequency of 2 to 60 Mhz is provided. The pulsed bias is selectively deposited on the uppermost part of the organic mask with regard to the dielectric layer. [Reference numerals] (104) locate a substrate in a chamber; (108) Selectively etch a pulsed bias; (112) Selective mask deposition step; (116) Selective etching step; (120) Remove the substrate from the chamber; (AA) Start; (BB) Stop