Selective etching of InP and InGaAsP over AlInAs using CH4/H2 reactive ion etching

Abstract

Selective etching of InP and InGaAsP over AlInAs was obtained using CH4/H2 reactive ion etching without the addition of a fluorine containing gas. By tuning the methane-to-hydrogen ratio, pressure, and power, sputter desorption of the reacted AlInAs etch products can be inhibited, thus enabling AlInAs to be used as an etch stop layer. The use of a fluorine free mixture enables dielectrics such as silicon dioxide or nitride to be used as the masking material.