Transmission electron microscopy (TEM) is employed to investigate the structural properties of (GaP)/(InP) short-period superlattices (SPS) grown at temperatures in the range of 425-490 °C by solid source molecular beam epitaxy. TEM results show that lateral composition modulation (LCM) is formed in the SPS layers grown at temperatures above 460 °C. Transmission electron diffraction results show that CuPt ordering occurs in all samples. It is shown that the degree of order increases, reaches a maximum at 460 °C, and then decreases, as the growth temperature increases. Photoluminescence examination (at 9 K) shows that the samples experience a reduction in band gap, which is in the range of 55-221 meV, as the growth temperature increases. The reduction is attributed to the combined effects of the LCM and CuPt-type ordering.
ASJC Scopus subject areas
- Physics and Astronomy(all)