Seminar Announcement

 

Time: 2017. 5. 17. Wed. 11:00 am – noon

Place: 56-106

 

 

Seminar title: Material and Device Innovations for Future Electronics and Sensors

Prof. Ali Javey

Electrical Engineering and Computer Sciences, UC Berkeley

Program Leader, Electronic Materials (E-Mat), Lawrence Berkeley National Laboratory

 

 

In this talk, I will give an overview of our research program at UC Berkeley on materials and device innovation for low power electronics, novel optoelectronics and wearable sensors. The topics will include materials properties and device physics of 2D semiconductors. I will present our recent advancements in defect passivation, contact engineering, surface charge transfer doping, and heterostructure devices of layered chalcogenides.  Notably, we have developed a defect repair/passivation technique that allows for observation of near-unity quantum yield in monolayer MoS₂. The work presents the first demonstration of an optoelectronically perfect monolayer. In addition, I will present our progress towards the use of 2D semiconductors for shortest transistors with a physical gate length of 1nm. Finally, I will present our recent advancements on new chemical sensor technologies. Specifically, I will present our recent advancement on fully-integrated perspiration analysis system that can simultaneously measure sweat metabolites, electrolytes and heavy metals, as well as the skin temperature to calibrate the sensors' response. Our work bridges the technological gap in wearable biosensors by merging plastic-based sensors that interface with the skin, and silicon integrated circuits consolidated on a flexible circuit board for complex signal processing. This wearable system is used to measure the detailed sweat profile of human subjects engaged in prolonged physical activities, and infer real-time assessment of physiological state of the subjects.

 

Biography. Ali Javey, Ph.D.

Conexant Systems Distinguished Professor

Professor of Electrical Engineering and Computer Sciences, UC Berkeley

Program Leader, Electronic Materials (E-Mat), Lawrence Berkeley National Laboratory

Co-Director, Bay Area PV Consortium (BAPVC)

Co-Director, Berkeley Sensor and Actuator Center (BSAC)

Associate Editor, ACS Nano

 

Ali Javey received a Ph.D. degree in chemistry from Stanford University in 2005, and was a Junior Fellow of the Harvard Society of Fellows from 2005 to 2006. He then joined the faculty of the University of California at Berkeley where he is currently a professor of Electrical Engineering and Computer Sciences. He is also a faculty scientist at the Lawrence Berkeley National Laboratory where he serves as the program leader of Electronic Materials (E-Mat). He is the co-director of Berkeley Sensor and Actuator Center (BSAC), and Bay Area PV Consortium (BAPVC). He is an associate editor of ACS Nano. Javey's research interests encompass the fields of chemistry, materials science, and electrical engineering. His work focuses on the integration of nanoscale electronic materials for various technological applications, including low power electronics, flexible

circuits and sensors, and energy generation and harvesting. He is the recipient of MRS Outstanding Young Investigator Award (2015), Nano Letters Young Investigator Lectureship (2014); UC Berkeley Electrical Engineering Outstanding Teaching Award (2012); APEC Science Prize for Innovation, Research and Education (2011); Netexplorateur of the Year Award (2011); IEEE Nanotechnology Early Career Award (2010); Alfred P. Sloan Fellow (2010); Mohr Davidow Ventures Innovators Award (2010); National Academy of Sciences Award for Initiatives in Research (2009); Technology Review TR35 (2009); NSF Early CAREER Award (2008); U.S. Frontiers of Engineering by National Academy of Engineering (2008); and Peter Verhofstadt Fellowship from the Semiconductor Research Corporation (2003).

 

Key publication in recent years:

1. S. B. Desai, S. R. Madhvapathy, A. B. Sachid, J. P. Llinas, Q. Wang, G. H. Ahn, G. Pitner, M. J. Kim, J. Bokor, C. Hu, H.-S. P. Wong, A. Javey, "MoS2 transistors with 1-nanometer gate lengths", Science, 354, 99-102, 2016.
2. W. Gao, S. Emaminejad, H. Y. Y. Nyein, S. Challa, K. Chen, A. Peck, H. M. Fahad, H. Ota, H. Shiraki, D. Kiriya, D.-H. Lien, G. A. Brooks, R. W. Davis, A. Javey. "Fully-integrated wearable sensor arrays for multiplexed in-situ perspiration analysis", Nature, 529, 509–514, 2016.
3. J. Bullock, M. Hettick, J. Geissbühler, A. J. Ong, T. Allen, C. M. Sutter-Fella, T. Chen, H. Ota, E. W. Schaler, S. De Wolf, C. Ballif, A. Cuevas, A. Javey, "Efficient silicon solar cells with dopant-free asymmetric heterocontacts", Nature Energy, 15031, 2016.
4. 185. K. Chen, R. Kapadia, A. Harker, S. Desai, J. S. Kang, S. Chuang, M. Tosun, C. M. Sutter-Fella, M. Tsang, Y. Zeng, D. Kiriya, J. Hazra, S. R. Madhvapathy, M. Hettick, Y.-Z. Chen, J. Mastandrea, M. Amani, S. Cabrini, Y.-L. Chueh, J. W. Ager III, D. C. Chrzan, A. Javey. "Direct growth of single crystalline III-V semiconductors on amorphous substrates", Nature Communications, 7, 10502, 2016.
5. M. Amani, D.-H. Lien, D. Kiriya, J. Xiao, A. Azcatl, J. Noh, S. R. Madhvapathy, R. Addou, S. K. C., M. Dubey, K. Cho, R. M. Wallace, S.-C. Lee, J.-H. He, J. W. Ager III, X. Zhang, E. Yablonovitch, A. Javey, "Near-Unity Photoluminescence Quantum Yield in MoS2", Science, 350, 1065-1068, 2015.
6. H. Ota, K. Chen, Y. Lin, D. Kiriya, H. Shiraki, Z. Yu, T.-J. Ha, and A. Javey, “Highly-deformable liquid-state heterojunction sensors”, Nature Communications, 5, 5032, 2014
7. X. Zhang, Z. Yu, C. Wang, D. Zarrouk, J.-W. T. Seo, J. C. Cheng, A. D. Buchan, K. Takei, Y. Zhao, J. W. Ager, J. Zhang, M. Hettick, M. C. Hersam, A. P. Pisano, R. S. Fearing, A. Javey. "Photoactuators and motors based on carbon nanotubes with selective chirality distributions", Nature Communications, 5, 2983, 2014.
8. C. Wang, D. Hwang, Z. Yu, K. Takei, J. Park, T. Chen, B. Ma, and A. Javey, “User-interactive electronic-skin for instantaneous pressure visualization”, Nature Materials, 12, 899-904, 2013.

For details, http://nano.eecs.berkeley.edu/

 

 

Note: For those who are interested in postdoc position in Prof. Ali Javey’s group, sometime in the afternoon of May 17th will be assigned for postdoc interview with Prof. Ali Javey.

 

 

Seminar hosted by

Takhee Lee, Prof. Dept. of Physics and Astronomy

Office: +82-0-880-4269   Cell: +82-10-6257-4234    E-mail: tlee@snu.ac.kr