Hard x-ray photoelectron spectroscopy reference spectra of Ga0.51In0.49P using a synchrotron radiation photon source

The ternary III–V semiconductor GaInP is a leading candidate material for the fabrication of ultra-bright red μLED (microlight emitting diodes) structures for application in high-resolution display technologies. When the pixel pitch is reduced to below 10 μm, increased nonradiative sidewall recombination in the active region of LEDs adversely affects the device's optical performance. The cause of this effect is a result of impurities in the lattice arising during the manufacture process. Correlating an understanding of the surface chemistry following the etch processes used to fabricate the mesa structured μLED arrays with the optical performance is essential to develop fabrication approaches to maximize the internal quantum efficiency of the fabricated quantum well structures. In this study, high intensity hard x-ray photoelectron spectroscopy measurements, acquired at a photon beam energy of 6 keV, have been used to acquire reference spectra of the chemical composition of epitaxially grown planar lattice matched Ga0.51In0.49P on a GaAs up to a sampling depth of approximately 20–30 nm into the bulk region of the sample. Using the National Institute of Standards and Technology Spectroscopy Soft and Tender II beamline at the National Synchrotron Light Source, Brookhaven National Laboratory, a survey scan of the sample along with high-resolution scans of key core levels In 3d, Ga 2p, Ga 3d/In 4d, P 1s, P 2p, and contaminant O 1s were obtained to provide baseline photoemission data on chemical composition.