Photoluminescence and electron transport properties of silicon-doped Ga/sub 0.52/In/sub 0.48/P/GaAs grown using a valved phosphorus cracker cell in solid source molecular beam epitaxy

摘要

We report the transport and photoluminescence (PL) properties of silicon-doped GaInP layers grown on GaAs[100] substrate using a valved phosphorus cracker cell in solid source molecular beam epitaxy (SSMBE). Within the range of silicon (Si) effusion cell temperature investigated (900 to 1200/spl deg/C), the highest electron concentration obtained was 7.7/spl times/10/sup 18/ cm/sup -3/ and 3.2/spl times/10/sup 18/ cm/sup -3/ at room temperature and 77 K, respectively. The concentration decreased with further increase in the silicon cell temperature. The Hall mobility at 300 K varied from 356 to 1720 cm/sup 2//Vs within the range of electron concentration measured (4.5/spl times/10/sup 16/ to 7.7/spl times/10/sup 18/ cm/sup -3/). Except for the sample grown at the highest silicon cell temperature (1200/spl deg/C), the PL spectrum of other samples showed a dominant peak attributed to Si donor-to-band transition (D-B), which shifted to higher energy following an increase in the electron concentration. This phenomenon was attributed to the Burstein-Moss effect. The blue shift of the (D-B) transition peak at increasing temperature was attributed to thermal ionization of the Si donors. The sample grown at the highest Si cell temperature showed a PL, peak at /spl sim/1.913 eV which was attributed to transition between the conduction band and Si acceptor (B-A), with an activation energy of /spl sim/57.2 meV as deduced from the PL spectrum. Temperature-dependent Hall measurements confirmed the amphoteric behaviour of the Si dopant in this sample.