Atomically thin 2D-dimensional materials have attracted significant attention from the scientific community in the last few years due to their potential exotic transport physics and prospects for technological applications in various fields. As the first prototype of layered structures, graphene and graphene like inorganic layered materials has been synthesized and widely studied for its unusual electrical, optical, mechanical properties. The main advantage of graphene-based transistors is the associated carrier high mobilities. However, several problems remain with graphene due to absence of a band gap which is essential for transistor applications. The discovery of graphene opened the door to 2D crystal materials. Following graphene, there has been emerging interest in exploring other single-sheet 2-D layered structures such as MoS2, WS2, MoSe2, WSe2 semiconductor with a finite and direct band gap in contrast to graphene which is gapless and thus can potentially find widespread applications in next generation electronics and energy technology. Being monolayer in thickness, their performances in transistor devices are highly dependent on their interface with the substrate and atmospheric adsorbates. We attempt to address few issues by fabricating single layer MoS2 transistors on self assembled, ultrathin, hybrid organic-inorganic, and high-k nanodielectrics. We observe low operating voltages and improved performance. Also, uniform coverage of MoS2 transistors with silicon nitride grown by plasma-enhanced chemical vapor deposition completely removes the hysteresis while the device mobility can be improved dramatically. Atomically thin MoS2 shows sensitive detection of gases such as NH3 and NO2 at room temperature and atmospheric pressure. Also, the few layers of MoS2, WS2 and its composite with RGO can be suitable in next generation field emitter devices due enhanced performance.
Dr. Dattatray Late has completed his MSc and PhD degree (2008) in Physics from University of Pune (India). After completing his PhD with, he joined as a DST Post-doctoral Fellow on Nanoscience & Technology at JNCASR, Bangalore (2008-2010). Then he moved to Department Materials Science and Engineering, Northwestern University (USA) Chicago, as a Postdoctoral Fellow (2010-2012). Currently he holds a position of Scientist, DST Ramanujan National Fellow and AcSIR Assistant Professor at CSIR-National Chemical Laboratory. His current research interest includes "Synthesis of atomically thin nanosheets of graphene and 2D inorganic layered materials for various Nanoelectronics device applications. He has authored or co-authored more than 50 research papers in international journals.