Quartz versus PBN—The effect of crucible type on undoped LEC GaAS

Undoped semi-insulating GaAs crystals were grown in a low pressure LEC system using quartz and pyrolytic boron nitride (PBN) crucibles. Crystals grown in PBN crucibles are consistently semi-insulating from the seed end to the tail end. Crystals grown in quartz crucibles have lower Hall mobility. Other properties such as dislocation etch-pit of conductive material beginning from the seed end of the crystal, and have lower Hall mobility. Other properties such as dislocation etch-put density, implant profile, and thermal conversion characteristics of the two types of crystal are about the same.