DRY ETCHING OF INGAASP/INP STRUCTURES BY REACTIVE ION-BEAM ETCHING USING CHLORINE AND ARGON

Very smooth InGaAsP/InP surfaces and sidewalls were obtained by using the enhanced sputtering effect of Ar addition to Cl2 etching gas in RIBE. The substrate temperature was raised to 180-degrees-C in order to remove involatile chlorides and impurities. Moreover, a vertical sidewall with no lateral etching under the mask was realized at the same time. This enables submicron dry etching for heterostructure devices.