Growth of GaP_{1 − x − y}As_yN_x on Si substrates by chemical beam epitaxy Available to Purchase

Chemical beam epitaxy has been used to grow layers of GaP_1 − xN_x, GaP_1 − yAs_y, and nearly lattice-matched layers GaP_{1 − x − y}As_yN_x on Si substrates. To address the issue of antiphase domain generation associated with the growth of polar semiconductors on Si, misoriented Si(001) substrates have been used combined with a carefully designed GaP buffer layer growth. The reflection high-energy electron diffraction pattern exhibits a (2 × 4) surface reconstruction after GaP buffer layer and GaP(As,N) graded layer growth, indicating the good surface quality and planarity of the grown layers. Sample composition was obtained by simultaneous acquisition of Rutherford backscattering spectrometry and nuclear reaction analysis, indicating a linear dependence of N and As mole fractions on the flux of their respective precursor. GaP_{1 − x − y}As_yN_x layers grown on Si substrates have a lattice mismatch not larger than ±0.005 for N contents in the range 0.02 < x < 0.05. High-resolution X-ray diffraction reciprocal space maps demonstrate a good crystalline quality. Intense photoluminescence spectra have been measured in all GaP_1 − xN_x and GaP_{1 − x − y}As_yN_x layers, as it is expected for direct bandgap materials. Two wide overlapped emission peaks are observed in all the spectra, most likely related to near bandgap recombination. The position of the higher energy peak for GaP_1 − xN_x and GaP_{1 − x − y}As_yN_x layers has been compared to bandgap energy calculations using the band anticrossing model, showing good agreement.