FABRICATION OF A HIGH-PERFORMANCE INGAASP INP INTEGRATED LASER WITH BUTT-COUPLED PASSIVE WAVE-GUIDES UTILIZING CH4/H-2 REACTIVE ION ETCHING/

We obtained high-performance 1.3 mu m InGaAsP/InP buried heterostructu re lasers integrated with butt-coupled waveguides using reactive ion e tching (RIE) for mesa definition, brief chemical cleaning for damage r elief and low-pressure metalorganic vapour phase epitaxy for the epita xial layer growth. We measured a coupling efficiency between the activ e layer and the passive waveguide layer of over 91 +/- 1.6% per facet across a quarter of a 2 inch InP wafer. The threshold current and the slope efficiency were 13 mA and 0.26 mW mA(-1), respectively, of the 7 00 mu m long integrated laser. This excellent uniformity and high perf ormance demonstrate that RIE coupled with slight chemical treatments c an be successfully used to fabricate high-quality integrated photonic devices. Transmission electron microscopy observation revealed RIE-ind uced strains and dislocation loops around the etched mesa after the re growth, which were proposed to be responsible for the inferior charact eristics of the lasers with mesas that were reactive ion etched but ha d not been cleaned in HBr-based solution.