Electrical property and structural analysis of amphoteric impurity Ge doped GaSe crystal grown by liquid phase growth

In order to improve conversion efficiency of THz wave generation, Germanium (Ge)-doped gallium selenide (GaSe) single crystals have been grown by Temperature Difference Method under Controlled Vapor Pressure (TDM-CVP). In this article, electrical property and lattice constant of Ge doped GaSe (GaSe:Ge) crystal are compared with that of not-intentionally doped GaSe crystal. Compared with non-doped GaSe crystal, carrier concentration p was decreased by Ge-doping (not-intentionally doped GaSe p=3.2×1015 cm−3 at 255 K, GaSe:Ge p=4.9×1014 cm−3 at 255 K). In addition, it has been confirmed that lattice constant of GaSe crystal increased with doping Ge concentration increased.