Vibrational mode and dielectric function spectra of BGaP probed by Raman scattering and spectroscopic ellipsometry

Abstract

The influence of boron incorporation in Bx Ga1-xP (0<x<=6%) layers on the dielectric function spectrum and on the vibrational mode spectrum has been studied. BGaP layers were grown by metal-organic vapor phase epitaxy, using a GaP interlayer, on Si and, for reference purposes, also on GaP substrates. The boron content of the layers was determined by high-resolution x-ray diffraction. Two vibrational modes arising from the two boron isotopes 10BGa and 11BGa were observed in the Raman spectrum, increasing in scattering strength and shifting to higher frequencies with increasing boron content at a rate of (1.40+/-60.20) cm-1/% and (1.41+/-0.14) cm-1/% for the 10BGa and 11BGa modes, respectively. Spectroscopic ellipsometry was used to asses the pseudodielectric function of the BxGa1-xP layers. The main effect of boron incorporation is a strong broadening of the E1 interband transition with increasing boron content due to alloy disorder and inhomogeneous random strains introduced by the large size mismatch of boron. However, upon the addition of arsenic to BGaP, i.e., forming BxGa1-xAsyP1-y with y~10%, a clear low-energy shift of the E1 interband transition is resolved. A small low-energy shift (~20 meV) of the lowest direct bandgap has also been observed for BxGa1-xP layers with x<=0.7% grown on GaP substrates

Silicon‐Lattice‐Matched Boron‐Doped Gallium Phosphide: A Scalable Acousto‐Optic Platform

“…Here, we demonstrate the first integrated photonic devices in commercially available BGaP grown at the 12-inch wafer scale. [31][32][33][34] We first demonstrate techniques for both hybrid and suspended device fabrication using standard semiconductor processing methods, which can be readily adapted to a variety of material systems and architectures. We then characterize BGaP's optical loss through photonic resonators obtaining lower bounds of the material-limited optical quality factors at visible (650-800 nm) and telecom (1530-1565 nm) wavelengths to be Q i, vis ≳ 25, 000 and Q i, tel ≳ 200, 000, respectively.…”

Band structure properties of novel BxGa1−xP alloys for silicon integration

“…10 Therefore, part of the observed decrease in the SPV-measured bandgaps with increasing B content in Fig. 1(c) is due to strain.…”

“…However, (BGa)P is a little known material system with little published experimental data on its optical characteristics. 10 In this work, we have grown novel B x Ga 1Àx P layers on silicon substrates and investigated their band-structure properties using surface photo-voltage (SPV) spectroscopy. Furthermore, to verify the suitability of this novel material for silicon integration, we have demonstrated the high crystal quality and promising optical material properties from high temperature annealed lattice matched monolithically integrated Ga(NAsP)/(BGa)P multi-quantum well heterostructures (MQWHs) on a (001) silicon substrate, where a novel (BGa)P layer is used for strain compensation purposes.…”