LP-MOVPE GROWTH AND CHARACTERIZATION OF WIDE-GAP INGAASP/INP LAYERS (LAMBDA-G LESS-THAN 1.2-MU-M) FOR OPTICAL WAVE-GUIDE APPLICATIONS

The growth of wide-gap (lambda-g < 1.2-mu-m) InGaAsP/InP layers using low-pressure MOVPE was investigated. A major problem encountered at standard growth conditions was the occurrence of a vertical concentration gradient of arsenic and phosphorus near the heterointerface becoming particularly pronounced at low AsH3 mass flows. The use of a thick (> 1-mu-m) InP buffer layer, i.e. a sufficiently long In-P predeposition period, was found to represent a convenient solution to this problem.