Research interests: silicon thin-film applied research; microelectronic circuits; device and process development for large area electronics
Karim S. Karim received his BASc in Computer Engineering in 1999 and his PhD in Electrical Engineering in 2002, both from the University of Waterloo, and completed an MBA in Health Sector Management from the Rotman School of Management at the University of Toronto in 2012. He was with Simon Fraser University from 2003 to 2007 as an Assistant Professor in the School of Engineering Science and is currently a Professor in the Department of Electrical and Computer Engineering at the University of Waterloo.
He was a founding member of the Center for Bioengineering and Biotechnology (CBB) at the University of Waterloo and served as its Associate Director from 2011 to 2017. Since 2017, Karim has served as the Associate Dean of Outreach and Diversity for the Faculty of Engineering.
Karim’s vision is to accelerate the adoption of cutting-edge X-ray imaging solutions in underserved regions globally to dramatically improve health outcomes. Since 1998, Karim has developed hardware and software technology for advanced X-ray imaging by incorporating unique ideas from solid-state physics into conventional engineering approaches where a manufacturing base already exists. He has trained over 40 PhD and MASc students and has co-authored 200+ publications and more than 20 unique patents.
Karim is a Full Member of the American Association of Physicists in Medicine, a Senior Member of the IEEE and a registered Professional Engineer in Canada. Karim is also a cofounder and CTO of KA Imaging, a UW spinoff located in the Waterloo Region that commercializes his lab’s X-ray imaging innovations into solutions for medical, industrial, veterinary, security and life sciences sectors.
- MASc, Electrical Engineering, University of Waterloo, 1999
- PhD, Computer Engineering, University of Waterloo, 2002
Active pixel sensors in thin film silicon technology
State-of-the-art Flat Panel Displays (FPDs) are based on a switch based passive pixel sensor architecture and while they have the advantage of being compact with pixel resolutions approaching 0.07 mm, their small output signal is swamped by external column charge amplifier and data line thermal noise thus limiting its use in low dose applications. The group is developing high resolution and ultra low noise hybrid pixel architecture based on three, two and one-transistor pixel amplifier designs for mammography tomosynthesis and dental cone beam computed tomography using industry standard amorphous and poly-silicon active matrix flat panel imager technology.
Large area mechanically flexible electronics
The group is developing thin film sensors (amorphous selenium) and devices (amorphous silicon thin film transistors) on plastic substrates. Plastic substrates are an emerging low cost alternative to glass driven primarily by the booming electronic display industry – as the larger display industry transitions to low cost, roll-to-roll plastic substrates, the price benefit is expected to trickle down to the smaller FPD industry. An additional bonus of fabricating an FPD on a plastic substrate is the substantial improvement in panel ruggedness at little additional cost but which is useful for medical devices used in a busy hospital environment.
High speed, high gain large area detectors using amorphous selenium
The group recently demonstrated the world’s first large area, high speed, uni-polar solid state charge detector based on a Frisch grid embedded in a selenium semiconductor. The same design was extended to a lateral metal-semiconductor-metal device detector design for high sensitivity selective blue and low diagnostic energy X-ray (<20 keV) absorption using amorphous selenium. Both devices extend the reach of low dark current amorphous selenium optical and X-ray detectors to high speed, high SNR digital imaging applications including photon counting mammography, high resolution diffraction imaging such as protein crystallography, and high SNR, fast solid state Single Photon Emission Computed Tomography (SPECT) Detectors.
- Active pixel sensors in thin film silicon technology
- Large area mechanically flexible electronics
- High speed, high gain large area detectors using amorphous selenium
Recent publications include:
A. Camlica, J. Liang, P.M. Levine, Z. Kabir, K.S. Karim, “Use of Pulse Height Spectroscopy to Characterize the Hole Conduction Mechanism of a Polyimide Blocking Layer Used in Amorphous-Selenium Radiation Detectors,” IEEE Transactions on Electron Devices, revised version under review, October 2019.
YH Tai, CH Lin, S Yeh, CC Tu, K.S. Karim, "LTPS Active Pixel Circuit With Threshold Voltage Compensation for X-Ray Imaging Applications," IEEE Transactions on Electron Devices 66 (2019): 4216-4220.
M.A. Martuza, C-H Lee, A. Sazonov, S. Boumaiza, K.S. Karim, "Wireless LC-Type Passive Humidity Sensor Using Large-Area RF Magnetron Sputtered ZnO Films," IEEE Transactions on Electron Devices 65, no. 8 (2018): 3447-3453.
A. Camlica, A. El-Falou, R. Mohammadi, P. M. Levine, K.S. Karim, “CMOSIntegrated Single-Photon-Counting X-Ray Detector using an Amorphous-Selenium Photoconductor with 11x11 μm Pixels,” IEEE Electron Devices Meeting Technical Digest, December 2018.
M.A. Martuza, S. Ghanbarzadeh, C-Z. Lee, C. Con, K.S. Karim, “Nanocrystalline Silicon Lateral MSM for Infrared Sensing Applications,” IEEE Transactions on Electron Devices, 65, no. 2 (2018): 584-590.
A. Cimprich, K.S. Karim, S.B. Young. (2017). Extending the geopolitical supply risk method: material “substitutability” indicators applied to electric vehicles and dental Xray equipment. The International Journal of Life Cycle Assessment (Springer Nature), 23(10) pp. 2024-42, 2018 (18 journal pages).
M. Wesolowski, C.C. Scott, B. Wales, K.S. Karim, J. Sanderson, C. Wesolowski, P. Babyn, “X-ray dosimetry during low intensity femtosecond laser ablation of molybdenum in ambient conditions,” IEEE Transactions on Nuclear Science, Vo 64(9), pp. 2519-22, Sep 2017.
T. Nano, T. Escartin, E. Ismailova, K.S. Karim, J. Lindstrom, H-K. Kim, I. Cunningham, “Apodized Aperture Pixel Design for Improved Quantum Efficiency of X-ray Detectors,” Medical Physics, 44, no. 9 (2017): 4525-4535.
Y. Fang, T. Ito, F. Nariyuki, T. Kuwabara, A. Badano, K.S. Karim, "Detective quantum efficiency simulation of a-Se imaging detectors using ARTEMIS," Medical Physics, 44(8): 4035–4039 (2017).
K-W. Shin, K.S. Karim, “a-Si:H TFT-Silicon Hybrid Low Energy X-ray Detector,” IEEE Transactions on Electron Devices, 64(4): 1624-1629 (2017).
U. Shafique, K.S. Karim, “Lateral Organic Semiconductor Photodetector: Effect of Electrode Spacing,” IEEE Journal of Selected Topics in Quantum Electronics, 23(5), 1-7, 2017.
A. Hamouda, K.S. Karim, M. Anis, “MIB (Model-based Initial Bias): Towards a Single Iteration Optical Proximity Correction,” IEEE Transactions on Computer Aided Design, October 2016. (6 journal pages).
S. Abbaszadeh, S. Ghaffari, S. Siddiquee, M.Z. Kabir, K.S. Karim, “Characterization of lag signal in amorphous selenium detectors,” IEEE Transactions on Electron Devices, February 2016. (6 journal pages)
C.C. Scott, A. Parsafar, A. El-Falou, P. M. Levine, K.S. Karim, “High Dose Efficiency, Ultra-high Resolution Amorphous Selenium/CMOS Hybrid Digital X-ray Imager,” IEEE International Electron Devices Meeting (IEDM) Technical Digest, December 2015. (4 journal pages)
Please see Karim S. Karim's Google Scholar profile for a current list of his peer-reviewed articles.