Fabrication of a Nanometer-Scale GaAs Ridge Structure with a 92-MHz Anode-Coupled Reactive Ion Etcher Using Cl2/N2 Mixed Plasmas

Abstract

A vertical etch profile of GaAs is achieved at a low bias voltage with a 92-MHz anode-coupled reactive ion etcher using chlorine-nitrogen plasmas. The added nitrogen gas not only dilutes the concentration of reactive chlorine radicals in the plasma also plays an important role in the vertical etching of GaAs. XPS analysis reveals no sidewall passivation by nitrogen. Reactive ion etching with a Cl₂/N₂ mixed plasma was used to fabricate ultra-fine GaAs patterns with a nanometer-scale ridge structure having a cross-section 15-nm wide by 150-nm high.