December 11, 2019
Colloquium Topic: CMOS Compatible Chemical Sensors for Healthcare Applications
Chronic diseases are a major healthcare challenge with significant human and economic cost. In the U.S., the economic burden of chronic diseases has reached ~$3.8 trillion in direct and indirect costs and is expected to increase as the population ages. Wearable sensors that can measure analytes from biofluids (e.g. sweat, saliva) have the potential to revolutionize healthcare by providing inexpensive, non-invasive and enhanced disease treatments. Since wearable sensors need to function reliably with minimal human intervention over extended periods of time, the foremost challenge is ensuring data accuracy. To address this important issue, we have proposed two main innovations. The bipolar junction transistor (BJT) device is proposed and demonstrated as a significantly superior transducer in comparison to existing sensor technology. [1-3] The BJT based sensors are shown to be well suited for mobile sensing applications with inherently simpler calibration, enhanced sensitivity and low power requirements. Another source of data inaccuracy is the failure of reference electrodes due to clogging during prolonged incubation in biofluids. We have demonstrated an innovative reference electrode that not only remains unclogged but is easier to miniaturize and integrate on a silicon chip. Hence, these two enhancements address important challenges in mobile healthcare sensing. Additionally, early diagnosis is an important factor for improving clinical outcome and reducing cost. We have applied a combined approach of nanofabrication, device simulation, and material studies to demonstrate nanowire sensors that not only have the lowest (~3%) reported sensor-to-sensor variations but also have significantly enhanced sensing characteristics, thus enabling early stage diagnosis of cancer as well as other diseases. [4]
[1] Sufi Zafar et al, Scientific Reports – Nature Publishing Group, 2017.
[2] Sufi Zafar, et al, Applied Physics Letters, 2015.
[3] Payel Das and Sufi Zafar, ACS Nano, 2015.
[4] Sufi Zafar et al, ACS Nano, 2018.
Colloquium Speaker: Sufi Zafar
Sufi Zafar is a Research Staff Member at the IBM T. J. Watson Research Center, Yorktown Heights, New York. She has extensive interdisciplinary research experience spanning biosensors, data modeling, charge transport and defect creation mechanisms in thin insulating films, quantum interference effects, device physics, materials science and nanofabrication. Sufi’s present research is focused on creatively leveraging her physics and nanofabrication expertise towards demonstrating innovative biosensing devices for applications in healthcare, agriculture and food safety. Her research has resulted in 78 publications (h-index of 40), 80 issued/pending patents and technology transfer for productization. She has presented several invited talks/tutorials at international conferences and served on scientific committees. Sufi has mentored postdocs, graduate students and new hires. She has received several prestigious internal and external awards, including IBM Research Division Award, IBM Outstanding Technical Achievement Awards, IBM Master Inventor Award and is an IEEE Senior Member and a fellow of the American Physical Society (APS).