Metal organic chemical vapor deposition of crack-free GaN-based light emitting diodes on Si (111) using a thin Al2O3 interlayer

Abstract

Crack-free GaN light emitting diodes (LEDs) have been grown by metal organic chemical vapor deposition on Si(111) substrates using an atomic layer deposition-grown Al2O3 interlayer. Devices on Si show a longer emission wavelength compared to those on sapphire. This is attributed to tensile strain in the layers on Si, which may increase indium incorporation. Internal quantum efficiency is similar on both substrates. Luminescence intensity versus current density measurements show higher efficiency for the LEDs on Si relative to sapphire at high drive currents. These results show comparable performance characteristics for GaN-based devices on Si and sapphire substrates.