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 degrees 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 similar to 170 cm(2).V(-1).s(-1) and a saturation current of similar to 1.6 mu A/mu m at V(d) = -1.5 V for the channel length and width of 15 and 280 mu m, respectively.