MOCVD Growth of InGaP on GaP Substrates and Its Application to Visible LEDs

Abstract
InGaP has been grown on GaP substrates by low pressure metalorganic chemical vapor deposition (MOCVD) using triethylindium, triethylgallium and phosphine. A buffer layer with step-graded alloy composition is inserted between the GaP substrate and the InGaP layer with a constant composition to reduce the influence of lattice mismatch. A trial fabrication of In0.34Ga0.66P light-emitting diodes(LEDs) has indicated that the diode efficiency is about one order of magnitude lower than commercially available GaAsP yellow LEDs. Further improvement in the efficiency is also discussed.