Low-damage dry-etched grating on an MQW active layer and dislocation-free InP regrowth for 1.55-/spl mu/m complex-coupled DFB lasers fabrication

A grating dry-etched through the upper wells of a multiquantum-well active layer has been characterized before and after regrowth. TEM observation and carrier lifetime measurements have shown growth-free defects of the epitaxial layers. As a consequence, quasi-100% monomode oscillation on /spl lambda/+1 mode has been achieved on complex-coupled distributed-feedback GaInAsP QW lasers fabricated with such grating.