Offset Drain ZnO Thin-Film Transistors for High-Voltage Operation

High-voltage thin-film transistors (TFTs) are useful building blocks for thin-film circuits. In this letter, we demonstrate ZnO high-voltage TFTs with offset drain. For these devices, the drain-to-source breakdown voltage increases from about 30 to >80 V as the drain offset length is increased from 0 to ∼ 2 μm, with little degradation in the I-V characteristics. The fabrication process is simple and uses a maximum temperature of 200 °C, which allows the high-voltage ZnO TFTs to be readily integrated in thin-film circuits on either glass or polymeric substrates.