A Quick and a Flexible Hydride Vapor Phase Epitaxy Process to Achieve Buried Heterostructure Quantum Cascade Lasers

Abstract

BH-QCLs were fabricated with regrowth of semi-insulating InP:Fe in hydride vapor phase epitaxy reactor. Two types of lateral ridge QCL designs were considered: (i) closely spaced ridges with double trenches and (ii) widely and uniformly spaced ridges. The etched depth varies from 6 to 15 µm in the former and 6 to10 µm in the latter. Double trenches of about 14 µm deep take only < 40 minutes to planarize while the same time is needed to planarize about 8 µm deep trenches with uniform ridges. In any case the achieved growth rate is higher by at least one order of magnitude than that can be achieved in MBE and MOVPE. Some fabricated BH-QCLs are characterized and they exhibit spatially monomode (TMoo) laser with an output power of as high as 2.4 W and wall plug efficiency of ~8-9% at RT under CW operation.