MATERIAL-SELECTIVE CHEMICAL ETCHING IN THE SYSTEM INGAASP-INP

Selective chemical etching of InP substrates in the GaInAsP/InP III-V system is described. A new etchant composed of hydrochloric and phosphoric acids is proposed, and a detailed description of application is provided. It is shown that illumination and the intentional introduction of defects on the surface of InP substrate material greatly facilitate its removal even from the slow etching (111)A face. Thus on GaInAsP LPE layers grown on (111)B-oriented InP substrates, both the (111)Ga,In and (111)As,P faces of the epilayers can be exposed. © 1979, The Electrochemical Society, Inc. All rights reserved.