Low-Temperature Electron-Beam-Assisted Dry Etching for GaAs Using Electron-Stimulated Desorption

Abstract
Low-temperature electron-beam(EB)-assisted dry etching for GaAs is developed to achieve highly anisotropic etching by reducing the side-etching caused by Cl2 gas etching. An extremely high etching rate ratio (EB-assisted etching/Cl2 gas etching) is achieved at a substrate temperature of -170°C. The mass spectra of the etching products during EB-assisted dry etching and Cl2 gas etching are measured. These correlate well with etching rate measurements.