IN-SITU PROCESSING OF III-V SEMICONDUCTORS - MILE STONES AND FUTURE-PROSPECTS

In situ processing combined with metalorganic vapor phase epitaxy (MOV PE), molecular beam epitaxy, or chemical beam epitaxy appears to be an attractive method for fabricating sophisticated optoelectronic device s such as buried heterostructure lasers, vertical cavity surface emitt ing lasers, and photonic integrated circuits. Successful reduction of residual contaminants at the regrowth interface and improvement in the optical and electrical quality of the regrown layer has been achieved by using in situ processing techniques. Device fabrication is alrady taking advantage of this kind of technology. Nevertheless, interface q uality between an in situ etched layer and a regrown layer has not yet reached the status of continuously grown interfaces. Ln this paper, p rogress of in situ processing is reviewed mainly focusing on our recen t studies on in situ HCl gas etching in MOVPE. The approach of two-ste p HCl gas etching has proven superior to obtain clean regrowth interfa ces, leading to the conclusion that the in situ processing can be wide ly used for advanced optoelectronic device fabrication.