High carrier mobility in orientation-controlled large-grain (>50 μm) Ge directly formed on flexible plastic by nucleation-controlled gold-induced-crystallization

High-carrier-mobility semiconductors on flexible-plastic are essential to realize flexible electronics, for this purpose, electrical properties of orientation-controlled large-grain Cie crystals on flexible-plastic dircctly formed by nucleation-controlled gold-induced-crystallization (GIC) are examined, and compared with those obtained by aluminum-induced-crystallization (AIC). The Ge crystals show p- Type conductions. Here, hole concentrations are 2.2 x10¹⁷ and 5.8 x 10²⁰cm ³ for GIC-Ge and AIC-Ge, respectively, which are explained on the basis of the solubility of Au and AL in Ge. Thanks to the low hole concentration, GIC-Ge shows high hole mobility (160cm²V^-1 'S^-1') compared with AIC-Ge (37cm²V^-1 'S^-1'). These demonstrate significant advantage of GIC to realize high-performance flexible-electronics.