Dr. Alok Ranjan
Invited Talk Topic: Dielectric Reliability Studies on Single Crystal Hexagonal Boron Nitride using Conduction AFM
Graphene and emerging 2D layered semiconductor materials have gathered enormous research interest for wide range of novel applications including optoelectronics and flexible nanoelectronics. These ultra-thin 2D semiconductor materials are highly sought after as a channel material in flexible transistors, given its intrinsic carrier mobilities are higher than silicon. While a lot of efforts have been directed towards growth of these materials on wafer scale, recent findings have shown that conventional dielectrics (e.g., SiO2, HfO2) are not compatible with 2D layered semiconductors. 2D hexagonal boron nitride (h-BN) have emerged as a potential dielectric material which can seamlessly integrate with almost all the 2D semiconductor materials reported so far. Hence, the reliability of h-BN as a gate dielectric is crucial for its successful commercialization. Interestingly, conduction AFM (CAFM) has been very successful to measure localized electrical properties of gate dielectrics and emerging nanoscale devices. In this talk, I will present our recent works where we extensively use CAFM to probe the electrical defects and understand mechanisms of dielectric breakdown in h-BN.
Bio: Dr. Alok Ranjan is currently a postdoctoral fellow at Engineering Product Development pillar at Singapore University of Technology and Design. Alok is passionate about developing experimental techniques for the physical and failure analysis techniques for the nanoscale devices. Alok has obtained his PhD in the field of nanoscale reliability of gate dielectrics under the mentorship of Prof. Pey Kin Leong (SUTD) and Dr. Sean O’Shea (IMRE, A*STAR). During PhD, Alok has been extensively applying the scanning probe microscopy techniques for single defect spectroscopy on gate dielectrics. Alok has published more than 20 technical papers and a book chapter, including 5+ technical papers presented as a lead author at International Reliability Physics Symposium (IRPS). Alok also sits on the reviewer panel for various journals including Applied Physics Letters, Scientific Reports, ACS Applied Materials and Interfaces, Microelectronics Reliability and conferences including International Symposium on the Physical and Failure Analysis of Integrated Circuits (IPFA).