PhD student Aftab's MS thesis work on "Exploring SiSn as channel material for LSTP device applications" has been accepted to Device Research Conference (DRC) 2013. DRC is a historical conference and inarguably the third major conference for the electron device community. This paper is the first ever display of potential opportunity that lies with a very simple low-cost method to use silicon's unlikely ally tin (Sn) - a group IV material. In the recent past leading authorities like Prof. Krishna Saraswat (Stanford University) and Prof. YC Yeo (NUS) have spearheaded the study of GeSn using MBE and/or MOCVD processes. Specification of the paper is here:
Exploring
SiSn as channel material for LSTP device applications
Aftab M. Hussain, Hossain M. Fahad,
Nirpendra Singh, Kelly R. Rader, Galo A. Torres Sevilla, Udo Schwingenschlögl
and Muhammad M. Hussain
Integrated Nanotechnology Lab, King
Abdullah University of Science and Technology, Thuwal, Saudi Arabia
Email: Aftab.hussain@kaust.edu.sa or MuhammadMustafa.Hussain@kaust.edu.sa, Phone: +966-544-700-072
We present a novel
semiconducting alloy, Silicon-tin (SiSn), as a channel material for LSTP device
applications. The diffusion of Sn into silicon has been explored to demonstrate,
for the first time, a MOSFET using SiSn as channel material. The semiconducting
alloy SiSn offers interesting possibilities in the realm of silicon bandgap
tuning and strain engineering. Previous works have shown that Sn diffuses into
silicon wafer [[1]], and that the SiSn
alloy is semiconducting [2]. Further, recent
studies have shown better MOSFET performance with GeSn as channel material, as
compared to Ge [3, 4]. To complement these
activities, we have explored diffusion of tin (Sn) into industry’s most widely
used substrate – silicon (100). The diffusion process of Sn into the silicon
lattice is low cost, scalable and manufacturable. We have studied SiSn as a
channel material using theoretical analysis, as well as, by MOSFET fabrication.
We observe better switching performance and an order-of-magnitude reduction in
Ioff of the SiSn pMOSFETs, while maintaining a similar Ion,
compared to the Si devices. We also note that the Ion/Ioff
ratio for pMOSFETs is improved with incorporation of Sn into the channel.
Fizika Tverdogo Tela, vol. 52, no. 6, p.
1215 (2010). [2] N. Amrane, et al., Infrared
Phys. Technol., vol. 36, p. 843 (1995). [3] S. Gupta, et al., IEEE IEDM, p. 16.1.1 (2011). [4] G. Han,
et al., IEEE IEDM, p. 16.7.1 (2011).
[5] K. Roy, et al., Proc. IEEE, vol.
91, no. 2, p. 305 (2003).