GROWTH OPTIMIZATION OF N-TYPE GAAS ON GAAS(201) SUBSTRATES

A study of the growth by molecular-beam epitaxy of Si-doped n -type Ga As on the GaAs(201) surface is presented. The motivation for attemptin g growth on this particular plane, apart from fundamental consideratio ns, is in connection with an investigation of off-axis transport in Ga As. The effects of growth temperature and doping on GaAs(201) and GaAs (100) samples have been compared using the Hall effect, low-temperatur e photoluminescence (PL), and Nomarski interference contrast microscop y. These studies showed that the PL, onset of conduction, and mobility behavior were very similar for both orientations. It was possible to dope n-GaAs/GaAs(201) reliably from N(Si) is similar to 4 x 10(14) to 6 x 10(18) cm-3, the highest mobility of 96 000 cm2 V-1 s-1 measured a t 77 K, being obtained for a sample doped at N(Si) is similar to 4 X 1 0(14) cm-3.