Donor gettering in GaAs by rare-earth elements

Abstract

Optical and electrical measurements of GaAs layers grown by liquid phase epitaxy with different amounts of Yb metal (0–1000 ppm) added to the Ga solution are reported. The presence of Yb during growth causes strong suppression of all donor-related optical transitions due to the effective removal of donors, as judged from Hall effect data. We have not found any appreciable increase of the background acceptor concentration during conductivity conversion from n-type to p-type, and thus conclude that dominant donor gettering occurs already in the Ga solution. No Yb3+ (4f 13)-related emission was detected in the as-grown GaAs layers.