Effect of Substrate Microdefects Due to Thermal Etching on the Near‐Junction Properties of GaP : Zn ,  O  Grown by Liquid Phase Epitaxy

Abstract

The effect of individual interfacial microdefects due to thermal etching on the cathodoluminescence (CL) and minority carrier diffusion length (Le) have been investigated with a scanning electron microscope for p -t y p e GaP: Zn,O layers grown by liquid phase epitaxy (LPE) on n -t y p e GaP substrates. For layers grown by conventional tilting or sliding techniques, both CL and Le are significantly reduced in the vicinity of a defect, probably because of the strong growth anisotropy generated there. However no degradation was observed for layers grown by an LPE technique that employs controlled substrate meltback and a Te-compensated growth solution. This difference may account for the improvement of about 15% in electroluminescent efficiency that has been reported for light-emitting diodes prepared from layers grown by a meltback technique.) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 138.38.0.53 Downloaded on 2015-06-23 to IP Vol. I22, No. 5 ) unless CC License in place (see abstract). ecsdl.org/site/terms_use address. Redistribution subject to ECS terms of use (see 138.38.0.53 Downloaded on 2015-06-23 to IP

Investigation of rapid thermally annealed GaP(001) surfaces in vacuum

“…Kocsis and Lendvay [2] studied the thermal decomposition of GaP(111) surfaces in vacuum and in hydrogen and argon atmospheres in a temperature range between T = 900 and 1300 K. They concluded that the thermal evaporation mechanism in vacuum and argon is similar, but in hydrogen the process is different. Michel [3] reported that in the fabrication of GaP : Zn,O light-emitting diodes by liquid-phase epitaxy, thermal etching at the optimum growth temperature seriously degrades the smoothness of the substrate surface. Imperfections present at the surface of the substrates, such as thermal etch pits or microsteps, also affected the p-n junction properties of the material.…”

Thermal annealing behaviours of GaP(001) surface

“…Gallium phosphide (GaP) is commercially one of the most important III-V semiconductors because of its application to electroluminescent and high-temperature electron devices. Michel [2] studied the effect of substrate microdefects due to thermal etching on the near-junction properties of GaP by using cathodoluminescence and scanning electron microscopy (SEM). He found that in an open-tube annealer system the thermal etch rate is independent of the carrier gas (N, He, Ar) but strongly dependent on the gas flow rate.…”