Nanoscale patterning by focused ion beam enhanced etching for optoelectronic device fabrication

A technique for highly resolved maskless patterning is obtained by combining focused ion beam lithography with wet chemical etching. When exposing InP to a focused Ga+-ion beam it acts like a photoresist with hydrofluoric acid (HF) as the appropriate developer. This technology allows the fabrication of filter gratings for single mode emitting lasers. Distributed feedback (DFB) and distributed Bragg-reflector (DBR) lasers with a high single mode stability and side mode suppression ratios (SMSR) above 50 dB were realized. The devices show no degradation after more than 10 000 h of cw operation. (C) 2001 Elsevier Science B.V. All rights reserved.