Self-assembled nanocrystalline ZnO thin film transistor performance optimization for high speed applications

Abstract

Abstract:ZnO nanocrystals grown at relatively low temperatures using various vacuum deposition techniques can yield semiconducting thin films of self-assembled nanocolumns 20-50 nm in diameter. Such films are suitable for the fabrication of high speed and transparent thin film transistors (TFTs). Unlike amorphous TFTs, the performance of ZnO transistors depends both on the crystal quality of nanocrystals and the electrical properties of boundary layers between them. We investigated the use of radio frequency sputtering, atomic layer deposition, and pulsed laser deposition techniques to fabricate self-assembled nanocrystalline thin films and determined the influence of deposition conditions on the performance of transistors. Device design and fabrication parameters were also optimized to demonstrate TFTs with high current density and high speed performance comparable to single crystalline-based transistors.

Remarkably high mobility ultra-thin-film metal-oxide transistor with strongly overlapped orbitals

“…The highly overlapped orbitals of SnO 2 is related to large atomic radius, one row below Zn in the periodic table. From the results of DOS and charge density distribution, the higher mobility than the state-of-the-art ZnO TFTs 32 33 is attributed to the highly overlapped s-orbitals of SnO 2 .…”