Flexible Single-Crystalline Ge p-Channel Thin-Film Transistors With Schottky-Barrier Source/Drain on Polyimide Substrates

Single-crystalline Ge p-channel thin-film transistors with Schottky-barrier source/drain (S/D) on flexible polyimide substrates are fabricated by a simple low-temperature process ( ?? 250??C), which preserves the high mobility of Ge channel. Adhesive wafer bonding and Smart-Cut techniques were utilized to transfer the single-crystalline Ge thin film onto polyimide substrates. The Schottky-barrier S/D is formed by using Pt/n-Ge contact, showing a low hole barrier height. The device has a linear hole mobility of ~ 170 cm²??V^-1??s^-1 and a saturation current of ~ 1.6 ??A/??m at V_d = - 1.5 V for the channel length and width of 15 and 280 ??m, respectively.