A Platform with Exquisite Film Profile Engineering in Oxide-Based Thin-Film Transistors for More-than-Moore Applications

Abstract

Recently we proposed and developed a unique film profile engineering (FPE) scheme for the fabrication of high-performance sub-micron oxide-semiconductor TFTs. In this scheme, profiles of the three pivotal thin films contained in a device, including gate oxide, oxide-semiconductor channel, and source/drain metal films, can be effectively tailored by selecting proper deposition tools with tunable process conditions. The fabricated IGZO, ZnO, and ZnON devices show decent performance in terms of high on/off current ratio (>10(8)) and steep subthreshold swing (<100 mV/dec). Since the low-temperature and the mature processes involved are highly compatible to the modern IC manufacturing, the fabricated devices can be readily integrated into the back-end-of-line (BEOL) of an advanced chip, making the FPE scheme useful and potential for a number of emerging applications in the more-than-Moore era.