SELECTIVE ETCHING OF INP AND INGAASP OVER ALINAS USING CH4 H2 REACTIVE ION ETCHING/

Selective etching of InP and InGaAsP over AlInAs was obtained using CH 4/H-2 reactive ion etching without the addition of a fluorine containi ng gas. By tuning the methane-to-hydrogen ratio, pressure, and power, sputter desorption of the reacted AlInAs etch products can be inhibite d, 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.