An atomic level etching technique for quasi-2D oxide semiconductors

Chu-Hsiu HSU^1*, Der-Hsien Lien¹

¹Institute of Electronics, National Yang Ming Chiao Tung University, Hsinchu, Taiwan

* Presenter:Chu-Hsiu HSU, email:chhsu.ee10@nycu.edu.tw

We demonstrate an atomic level etching technique to tune the thickness of ultrathin oxide semiconductor at nanometer scale, confirmed by atomic force microscopy (AFM) and electrical characteristics measurements. We show that the threshold voltage of such ultrathin quasi-2D oxide semiconductor (OSs) is tunable as a function of channel thicknesses. This etching approach is compatible to the back end of line (BEOL) technologies. Using an area-selective etching approach, the local thickness as well as the local threshold voltage of a channel can be engineered and designed to achieve multi-step logic devices.

Keywords: oxide semiconductor, threshold voltage adjustment, controllable etching