Dry Etching Characteristics of 16-nm Amorphous Carbon Layer in a Dual-Frequency Plasma Etcher

Abstract

The etching characteristics of a patterned amorphous carbon layer (ACL) in a magnetized inductively coupled plasma (MICP) etcher were investigated. The etch rate and etched profile dependences on the source power, the neutral gas pressure and the dual bias power ratio were investigated. We measured the ion energy distribution (IED), the ion flux, plasma density and electron temperature using an ion energy analyzer (IEA) and a dual Langmuir probe (DLP). The etching rate and the anisotropy of ACL relative to change in the dual bias power ratio of two bias power generators operating at frequencies of 2 and 13.56 MHz were observed. The bowed profile could be improved by appropriate adjustment of the dual bias power ratio.