Selective dry etching of GaAs over AlGaAs in SF6/SiCl4 mixtures
- 1 November 1988
- journal article
- Published by American Vacuum Society in Journal of Vacuum Science & Technology B
- Vol. 6 (6) , 1641-1644
- https://doi.org/10.1116/1.584422
Abstract
Reactive ion etching of GaAs with high selectivity over Al0.29Ga0.71As in SF6/SiCl4 mixtures was studied. Selectivity, surface morphology, and anisotropy were investigated over a wide range of pressures (15–100 mTorr), dc bias values (−20 to −300 V), and SF6-to-SiCl4 ratios (0–0.5). Higher pressures, lower dc biases, and higher SF6/SiCl4 ratios increase the GaAs-to-AlGaAs selectivity. Electron spectroscopy for chemical analysis indicates that the formation of nonvolatile aluminum fluoride on AlGaAs is responsible for the selective etch process.This publication has 0 references indexed in Scilit: