Speaker: Ross Walker
Host Faculty: Professor Jon Viventi
Sensor systems are a ubiquitous part of modern life and make huge impacts on how we deal with disease and injury, how we communicate and travel, and how we understand our environment and ourselves. Miniaturized sensors fueled by the MEMS revolution and progress in integrated circuit technology have paved the way for small, cheap, and highly effective sensor systems. Quantum physics and materials science are bringing in the next wave of sensors that can be made orders of magnitude smaller and are capable of new modes of information transduction. Two emerging sensor systems outlined below will be discussed, and future research directions will be presented.
Progress in head-mounted neural recording platforms at Stanford University, reported in the literature as the ‘Hermes’ project series, has motivated the research and design of a new front-end ASIC solution for broadband acquisition of 96 channels of neural data from chronically implanted “Utah” intracortical microelectrode arrays (UEA). The proof-of-concept chip consumes 6.4mW from 1.2V while occupying 5mm × 5mm in 0.13µm CMOS, and enables basic neuroscience as well as neural prosthetics research by providing high fidelity simultaneous recordings from all available UEA channels with low power consumption and a compact form factor. The front-end IC and functional HermesE system prototype will be discussed.
A new label-free electronic biosensing technique is explored, based on quantum information transduction of a solvated analyte’s chemical composition. The technique combines the advantages of conventional label-free and mass spectrometry technologies by leveraging the physics of non-adiabatic, quantum, charge-transfer-related transitions at nanofabricated electrochemical interfaces. The quantum transition-based current is a rich new source of information about chemical composition, upon which we are creating a new biomolecular sensing platform for detection of biothreat agents such as botulinum toxin.
About the Speaker
Ross Walker is a graduate student at Stanford University. He received the B.S. degree in electrical engineering and the B.S. degree in computer science from the University of Arizona, Tucson, in 2005. In 2007, he received the M.S. degree in electrical engineering from Stanford University, Stanford, CA. Since 2007 he has been working toward the Ph.D. degree at Stanford University. He recently defended his thesis research and is set to graduate in June 2013. From 2003-2004 he held internships at IBM and National Semiconductor, both in Tucson, AZ. In 2006 he held an internship at Linear Technology, Milpitas, CA. His research interests include mixed signal integrated circuit design with emphasis on sensor interfacing, signal processing, and biomedical applications. Ross has worked on biomedical optical imaging systems, direct neural interface systems, quantum biomolecular transducers, and other sensor related projects.