InGaN/GaN double-heterostructure LEDs on HVPE GaN-on-sapphire substrates

Abstract

InGaN double heterostructure light emitting diodes (DH-LEDs) were fabricated on hydride vapor phase epitaxy (HVPE) GaN- on-sapphire substrates. These substrates consisted of a thick HVPE GaN layer grown directly on sapphire and eliminated the need for the growth of a low-temperature buffer layer for GaN epitaxy on sapphire. Homojunction and DH-LEDs have been fabricated with various composition InGaN active regions resulting in strong electroluminescence in the blue, green, and yellow portion of the visible spectra. These devices had turn-on voltages as low as 3.6 volts.