Wavelength stable, p-side-down green light emitting diodes grown by molecular beam epitaxy

Abstract

p-side-down, single heterostructure n-InGaN/p-GaN light emitting diodes grown by molecular beam epitaxy exhibited stable peak emission wavelengths as long as 550 nm for current densities in excess of 100 A/cm2, and minimal efficiency droop up to 150 A/cm2 without the use of an electron blocking layer. This behavior is consistent with the formation of a two-dimensional hole gas in the n-InGaN layer and a higher barrier to electron overflow in the conduction band due to the negative polarization charge at the n-InGaN/p-GaN interface.