Thermal Decomposition of InP and Its Influence on Iso‐Epitaxy

Abstract

The effects of rapid thermal degradation of substrate on the quality of epitaxially grown layers are generally underestimated. Scanning photoluminescence, photocurrent, and etch pitting techniques have been used to evaluate the influence of substrate decomposition on the quality of epitaxially grown layers. Growth on substrates protected with an cover piece results in epitaxial layers with localized regions of low luminescence and high dislocation density. These are present even in layers with a very good surface morphology. The use of source‐piece protection, in conjunction with a shallow In meltback prior to epitaxy, eliminates the deleterious effects of thermal decomposition. The incorporation of these steps into the growth of device wafers greatly improves the yield of light emitting diodes.