Prevention of Surface Corrugation Thermal Deformation for InGaAsP/InP DFB Lasers

Abstract

Thermal deformation mechanism for surface corrugations fabricated on InP and InGaAsP crystal surfaces has been analyzed, and threshold value existence for PH 3 partial pressure in H 2 ambient to prevent the deformation is shown. It has been verified that as-fabricated corrugation height can be conserved even after the LPE process by preventing thermal deformation before growth and by retaining an adequate supersaturation for the growth melt. Applying the results of these studies, heterostructures for 1.3∼1.5 µm region DFB lasers with first order grating of near 1000 Å corrugation height have been fabricated.