In-situ selective area etching by using HCl gas in an MOVPE reactor

Aiming at improving the crystalline quality of a regrowth interface for integrated optical devices, we investigated in-situ gas etching in the selective area using hydrogen-chloride (HCl) gas with metalorganic vapor-phase epitaxy. The etching pattern at the mask edge was limited by (111)B and (100) planes. The depth of etching in the selective area can be controlled by the mask width and etching conditions. At a high etching temperature, the etching depth increases as the mask width is increased or the gap width is decreased. On the other hand, at a low etching temperature, etching depth is constant.