pMOSFET with CVD-grown 2D semiconductor channel enabled by ultra-thin and fab-compatible spacer doping

Abstract

We present the first demonstration of p-MOSFET with a high ON current of $10^{-5}\mathrm{A}/\mathrm{u}\mathrm{m}$ and good S.S. $\sim 80\mathrm{m}\mathrm{V}/\mathrm{d}\mathrm{e}\mathrm{c}$. MOSFETs have the advantage of lower access resistance compared to Schottky barrier FETs. This requires spacer doping. Here, we introduce a self-limiting, fab-compatible process which consists of $\mathrm{W}\mathrm{O}_{\mathrm{x}}$ obtained from $\mathrm{W}\mathrm{S}\mathrm{e}_{2}$ by O <inf xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</inf> plasma conversion. We analyze the process condition which enhance the doping effect. We quantify the doping level and the impact of the channel bandgap. We demonstrate a self-aligned version of the spacer doping for MOSFET fabrication.