Visionaries in Technology

Thayer Distinguished Speaker Series

Thayer School's Visionaries in Technology series honors engineers and scientists whose insights have benefited humanity through revolutionary engineering solutions, paradigm shifting scientific advances, novel fields of inquiry, or policy shaping debate.

The 2018 event took place on Friday, November 2nd.

Roger Howe

This year's speaker was Roger T. Howe, the William E. Ayer Professor in the Dept. of Electrical Engineering at Stanford. He received a BS in physics from Harvey Mudd College and a PhD in electrical engineering from the University of California, Berkeley. After faculty positions at CMU and MIT from 1984–1987, he returned to Berkeley where he was a Professor until 2005. His research group has worked on MEMS sensors and actuators for over 30 years, with the focus shifting to biomolecular sensors and thermionic energy conversion over the past decade. He is currently on sabbatical as a visiting professor at Dartmouth. He has received several awards for his research in MEMS and is a member of the National Academy of Engineering. He co-founded Silicon Clocks, Inc. to commercialize MEMS resonators for electronic clocks. In 2010, the company was acquired by Silicon Labs, Inc. In 2016, he co-founded ProbiusDx, Inc. to commercialize a broad-spectrum biomolecular sensing platform based on his group’s research.

Resonant Systems for Physical and Biochemical Sensing

The phenomenon of resonance, in which vibrational energy is concentrated at a specific frequency, is a common feature of natural and engineered systems over a wide range of dimensions. Silicon’s outstanding mechanical properties and the power of silicon integrated electronics have together created microelectromechanical systems (MEMS) technology. Today’s mobile phones and watches contain several chips with resonating silicon microstructures, giving them their ability to sense motion. I will discuss progress toward improving both the sensitivity and stability of silicon motion sensors, as well as discuss some motivating applications. At a far smaller dimensional scale, electrons in intramolecular bonds have quantized vibrational energies that provide structural information about the molecule. In recent work at Stanford, a new sensor that can detect these energy states through their resonant interactions with tunneling electrons has been developed. In order to observe these quantum mechanical effects at room temperature, an ultralow noise feedback potentiostat is used to effectively “cool” the tunneling electrons. This sensor is being used in a broad-spectrum biomolecular sensing platform that requires little or no sample preparation. Analytes in complex media, such as the neurotoxin BoNT-A in serum, can be identified by pattern matching against reference scans of the analyte in a buffer solution. I will conclude the talk with perspectives on the opportunities and challenges involving in commercializing sensor technologies.