Low concentration GaSb grown from Sb-rich solutions by liquid phase epitaxy in the presence of erbium

In this article, we report the growth of GaSb layers by introducing the rare earth element Er into Sb-rich GaSb liquid phase epitaxy solutions. We find that the carrier concentration of GaSb layers can be effectively lowered due to the gettering of residual impurities and the suppression of complex acceptor defects in the presence of Er. Three intense sharp lines consisting of free exciton (FE) and excitons bound to neutral accepters (BE3 and BE4) dominate the low temperature photoluminescence spectra of Er-doped GaSb. Zn-diffused Er-doped GaSb diodes exhibit higher contact resistances and breakdown voltages due to lower carrier concentration than for equivalent undoped diodes.