Complementary Integrated Circuits Based on p-Type SnO and n-Type IGZO Thin-Film Transistors

Abstract

Oxide semiconductorsare highly attractive for the new-generation transparent/flexible electronics. In this letter, logic gates (inverter, NAND, and transmission gates) and three-stage ring oscillators based on n-type indiumgallium-zinc-oxide (IGZO) thin-film transistors (TFTs) and p-type tin monoxide (SnO) TFTs are presented. The IGZO TFTs show a mobility of 10.05 cm2/(V · s) and a threshold voltage of 5.00 V. The SnO TFTs exhibit a mobility of 1.19 cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> /(V·s) and a matched threshold voltage of -5.05 V. At a supply voltage of 10 V, the complementary inverters show an extremely high gain of 112 with a geometric aspect ratio of 5. The dynamic responses of the logic gates based on n-type IGZO and p-type SnO TFTs are also examined. The delay time of the inverter measured from dynamic response is 27.75 μs at a supply voltage of 10 V. The inverter, NAND, and transmission gates all exhibit ideal rail-to-rail output voltage behavior. At a supply voltage of 20 V, the three-stage ring oscillators are able to operate at 32.87 kHz, and the stage delay is 5.07 μs.