The talk will give a brief overview of recent research activities in the speaker's group covering advanced germanium CMOS devices and electronic transport studies in two-dimensional (2D) van der Waals (vdW) semiconductors. It will also describe ongoing experimental efforts on optoelectronic devices using vdW materials. Ultra-thin 2D transition metal dichalcogenides, such as MoS2, not only promise excellent short-channel control for sub-10 nm logic transistors but also exhibit a large photoresponse, high optical absorption, tunability of the band gap and high flexibility coupled with the ability to form defect-free heterointerfaces, making them highly attractive for a wide range of optoelectronic applications. Experimental results highlighting the trade-off between responsivity and speed in gated vdW ReS2 photodetectors through modulation of extrinsic and intrinsic trap concentrations will be presented. Recent results on engineering photo-amplification in electrostatically doped WSe2 n-p-n phototransistors and the photovoltaic effect in WSe2/ReS2 p-n heterojunction diodes will also be discussed.
Prof. Saurabh Lodha graduated from IIT Bombay in 1999 with a B. Tech (EE) followed by a Masters (ECE) and PhD (ECE) from Purdue University in 2001 and 2004 respectively. His graduate research focused on III-V metal/semiconductor interfaces and molecular electronics. From 2005-2010 he worked at Intel Corporation in Portland, USA, where he was part of the team responsible for the research and development of 45, 32 and 22 Si CMOS process technologies. He joined IIT Bombay in July 2010 where he is currently Associate Professor of Electrical Engineering, PI of the nanofabrication facility and co-PI of IIT Bombay's Research Park. He has been awarded the Swarnajayanti fellowship by DST in 2017 and the IRCC young investigator award in 2012. His research interests span the areas of advanced CMOS, 2D van der Waals devices and Si photovoltaics. He has co-authored over 120 papers in peer-reviewed international journals and conferences.