ECE Departmental Seminar

Antimonide Materials for Mid-Infrared Detectors and Focal Plane Arrays

Prof. Sanjay Krishna
University of New Mexico

Wednesday, 10/19/16, 12:00pm
Light Engineering 250

Abstract: Infrared imaging (3-25mm) has been an important technological tool since the first report of infrared detectors in 1950s. There has been a dramatic progress in the development of infrared antimonide based detectors and low power electronic devices in the past decade with new materials like InAsSb, InAs/GaSb superlattices and InAs/InAsSb superlattices demonstrating very good performance. One of the unique aspects of the 6.1A family of semiconductors (InAs, GaSb and AlSb) is the ability to engineer the bandstructure to obtain designer band-offsets. Our group (www.krishnairlab.com) has been proposing the investigation of 4th generation of infrared detectors, focal plane arrays and imaging systems.

My talk will revolve around three research themes.

The first theme involves the fundamental investigation into the material science and device physics of the antimonide systems. I will describe some of the challenges in these systems including the identification of defects that limit the performance of the detector. The use of “unipolar barrier engineering” to realize high performance single and dual band infrared detectors and focal plane arrays will be discussed.

The second theme involves looking into next generation infrared detectors. I will discuss some techniques for wafer level infrared detectors with superlattice membranes. The design, growth, farbrication and characterization of superlattice membranes will be presented.

In the final theme, I will describe the role of infrared imaging in bio-medical diagnostics. In particular, I will highlight some work on using infrared imaging in the early detection of skin cancer and for detection of flow in cerebral shunts. Using dynamic thermal imaging on over 100 human subjects, a sensitivity >95% and specificity >83% has been demonstrated. Commercialization of this technology will also be discussed.  

Bio: Sanjay Krishna is a Professor and Regents Lecturer in the Department of Electrical and Computer Engineering and Center for High Technology Materials at the University of New Mexico. He will be the George R Smith Chair in Engineering in the Electrical and Computer Engineering Department at Ohio State University starting in January 2017.Sanjay received his M.S. from IIT, Madras in 1994, MS in Electrical Engineering in 1999 and PhD in Applied Physics in 2001 from the University of Michigan. He joined UNM as a tenure track faculty member in 2001. He currently heads a group of 15 researchers involved with the development of next generation infrared imagers. Sanjay received the Gold Medal from IIT, Madras, Ralph Powe Junior Faculty Award, IEEE Outstanding Engineering Award, ECE Department Outstanding Researcher Award, School of Engineering Jr Faculty Teaching Excellence Award, NCMR-DIA Chief Scientist Award for Excellence, the NAMBE Young Investigator Award, IEEE-NTC, SPIE Early Career Achievement Award and the ISCS Young Scientist Award. He was also awarded the UNM Teacher of the Year and the UNM Regents Lecturer award. Sanjay has more than 200 peer-reviewed journal articles (h-index=44), two book chapters and seven issued patents. He is the co-founder and CTO of Skinfrared, a UNM start-up involved with the use of IR imaging for dual use applications including early detection of skin cancer. He is a Fellow of IEEE, OSA and SPIE.