T. Saitoh et al., LOW-TEMPERATURE DRY-ETCHING OF GAAS AND ALGAAS USING 92-MHZ ANODE-COUPLED CHLORINE REACTIVE ION ETCHING, JPN J A P 1, 36(12B), 1997, pp. 7650-7654
The etching characteristics and the damage induced by low-temperature
etching have been studied using 92-MHz anode-coupled reactive ion etch
ing. Due to the suppression of sidewall etching, vertical profiles of
GaAs and AlGaAs have been obtained by lowering the substrate temperatu
re during etching. The etching rates of GaAs and AlGaAs become identic
al at low temperatures. The exciton peak intensity in the photolumines
cence spectrum decreased with a decrease in etching temperature, sugge
sting a slight increase in damage in low-temperature etching. It is al
so found that pronounced stoichiometry change in the subsurface region
takes place in low-temperature etching.