Publications

2024 Journals

Patrik Rogalla, Mary May, Sandeep Ronghe, Sonja Kandel, Jay Potipcoe, Nikhil S. Patil, Karim S. Karim, and Jeffrey B. Mendel. (2024). Improved visibility of lines and tubes on portable dual energy chest X-ray: Assessment in a non-radiological reviewing environment. Canadian Association of Radiologists Journal.

2024 Conference Proceedings

V Venkatesh, N Patil, KS Karim. (2024). Implementation of a Portable Spectral Dual Energy X-Ray Image Detector in the Intensive Care Unit of a community hospital in Canada. The American Society for Emergency Radiology (ASER), Washington, United States of America Paper

Abdollah Pil-Ali*, Zachary Birch*, Sahar Adnani*, Chris C. Scott*, Karim S. Karim. (2024). Kidney Stone Compositional Analysis and Identification using a Benchtop High-Resolution Multi-Modal X-ray PhaseContrast micro-CT Imaging System. SPIE International Medical Imaging Symposium, San Diego, United States of America

Sahar Adnani*, Abdollah Pil-Ali*, Karim S. Karim. (2024). Enhancing Temporal Performance of a-Se Detectors using a Low-temperature Hole-Blocking Bilayer Design. SPIE International Medical Imaging Symposium, San Diego, United States of America

P. Rogalla, J. Favero Prietto Dos Santos, B.J. Wintersperger, S. Tilley II*, K.S. Karim, F.A. Sanchez. (2024). Single-exposure Dual-Energy Imaging improves identification of coronary artery calcium and valve/ vascular calcifications on Chest X-ray. Radiological Society of North America Annual Meeting, Chicago, United States of America

P. Rogalla, M. May, S. Ronghe, J. B. Mendel, S. Kandel, K. S. Karim. (2024). Dual-energy acquisition of portable chest X-rays: added diagnostic value in a non-radiological reviewing environment. European Congress on Radiology, Austria

KS Karim, S Tilley II*. (2024). Dual-Energy Tomosynthesis of the Chest using a Triple Layer X-ray Detector. 7th Workshop on Spectroscopic X-ray Detectors, Geneva, Switzerland

2015 Journals

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, accepted December 2015, in press (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, accepted December 2015, in press (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, October 2015, in press. (4 journal pages)

S. Ghaffari, S. Abbaszadeh, S. Ghanbarzadeh, K.S. Karim, “Characterization of Optically Sensitive Amorphous Selenium Photodetector at High Electric Fields,” IEEE Transactions on Electron Devices, May 2015, in press. (6 journal pages)

K. Wang, S. Abbaszadeh, K.S. Karim, J.A. Rowlands, A. Reznik, “Reactive ion assisted deposition of cerium oxide hole-blocking contact for leakage current suppression in amorphous selenium multilayer structure,” IEEE Sensors Journal, 15(7), pp.3871-6, July 2015. (6 journal pages)

A. Parsafar, C. Scott, A. El-Falou, P. Levine, K.S. Karim, “Direct-Conversion CMOS X-Ray Imager with 5.6 μm × 6.25 μm Pixels,” IEEE Electron Device Letters, 36(5), pp. 481-3, May 2015. (3 journal pages)

2015 Conference Proceedings

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,” in the 2015 IEEE International Electron Devices Meeting (IEDM), accepted as oral.

T. Nano, T. Escartin, K.S. Karim, I. Cunningham, “The new generation of x-ray detectors: higher DQE and less aliasing with lower exposures,” in SPIE Medical Imaging 2016: Physics of Medical Imaging, San Diego, USA, accepted as oral.

M.K. Russ, A. Jain, S.V.S. Nagesh, C.N. Ionita, C.C. Scott, K.S. Karim, D. R. Bednarek, S. Rudin, “Quantitative comparison using generalized relative object detectability (G-ROD) metrics of an amorphous selenium detector with high- resolution microangiographic fluoroscopes (MAF) and standard flat panel detectors (FPD),” in SPIE Medical Imaging 2016: Physics of Medical Imaging, San Diego, USA, accepted as poster.

S.L. Maurino, I. Cunningham, K.S. Karim, “Theoretical and Monte Carlo optimization of a stacked three-layer flat-panel x-ray imager for applications in multi-spectral diagnostic medical imaging,” in SPIE Medical Imaging 2016: Physics of Medical Imaging, San Diego, USA, accepted as poster.

K.S. Karim, “Ethics 2.0: An introspective approach to understanding and taking ownership of your actions,” in Canadian Engineering Education Association Annual Conference, Hamilton, Canada, accepted as oral, May 2015.

M. Russ, S. V. Setlur Nagesh, C. N. Ionita, C. Scott, K. S. Karim, D. R. Bednarek, S. Rudin, “Relative Object Detectability Evaluation of a New High Resolution a-Se Direct Detection System Compared to other Indirect Micro-Angiographic Fluoroscopic (MAF) Detectors,” in American Association of Physicists in Medicine (AAPM) Annual Meeting, March 2015, accepted as oral.

E. Ismailova, K.S. Karim, I. Cunningham, “Apodized-Aperture Pixel Design to Increase High-Frequency DQE and Reduce Noise Aliasing in X-Ray Detectors,” in SPIE Medical Imaging 2015: Physics of Medical Imaging, Orlando, USA, February 2015.

2014 Journals

G.P. Lindberg, T. O’Loughlin, N. Gross, A. Mishchenko, A. Reznik, S. Abbaszadeh, K.S. Karim, G. Belev, B. Weinstein, “Photo-crystallization in a-Se layer structures: effects of film-substrate interface-rigidity,” Journal of Applied Physics, vol. 116, November 2014. (6 journal pages).

S. Abbaszadeh, A. Tari, W.S. Wong, K.S. Karim, "Enhanced Dark Current Suppression of Amorphous Selenium Detector With Use of IGZO Hole Blocking Layer," IEEE Transactions on Electron Devices, 61, no. 9, pp. 3355-3357, September 2014.

U. Shafique, C. Santato, K.S. Karim, “Lateral Organic Semiconductor Photodetector I: Use of an Insulating Layer for Low Dark Current,” IEEE Transactions on Electron Devices, August 2014, in press. (6 journal pages)

Y. Fang, K.S. Karim, A. Badano, "Monte Carlo Modeling of the DQE of a-Se X-Ray Detectors for Breast Imaging," Breast Imaging, Lecture Notes in Computer Science, vol. 8539, pp. 387-393, January 2014 (7 journal pages).

Y. Fang, KS. Karim, A. Badano. "Effect of burst and recombination models for Monte Carlo transport of interacting carriers in a-Se x-ray detectors on Swank noise." Medical Physics 41(1), January 2014. (6 journal pages).

S. Ghanbarzadeh, S. Abbaszadeh, KS Karim, “Low dark current amorphous silicon Metal-Semiconductor-Metal photodetector for digital imaging applications,” IEEE Electron Device Letters, January 2014 (3 journal pages)

2014 Conference Proceedings

C.C. Scott, S. Abbaszadeh, S. Ghanbarzadeh, G. Allan, M. Farrier, I. Cunningham, K.S. Karim, “Direct conversion x-ray imager with 25 micron pixel resolution for medical imaging applications,” Annual Meeting of the Radiological Society of North America (RSNA), accepted as oral, November 2014.

R.S. Mann, S. Ghanbarzadeh, K.S. Karim, “System design of a low-cost digital x-ray detector,” in Proceedings of the IEEE International Health Technology Conference, Montreal, Canada, June 2014.

U. Shafique, K.S. Karim, “UV Lateral Organic Semiconductor Photoconductor with Low Dark Current at High Electric Field,” Materials Research Society Symposium, San Francisco, USA, April 2014.

C.C. Scott, S. Abbaszadeh, S. Ghanbarzadeh, G. Allan, M. Farrier, I. Cunningham, K.S. Karim, “Amorphous selenium direct detection CMOS digital x-ray imager with 25 micron resolution,” in SPIE Medical Imaging 2014: Physics of Medical Imaging, San Diego, USA, February 2014.

2013 Journals

A.H. Goldan, J.A. Rowlands, O. Tousignant, K.S. Karim, "Unipolar time-differential charge-sensing in non-dispersive amorphous solids," Journal of Applied Physics, June 2013.

N. Allec, S. Abbaszadeh, C. Scott, K.S. Karim, and J.M. Lewin, "Evaluating noise reduction techniques while considering anatomical noise in dual-energy contrast-enhanced mammography," Medical Physics, Vol. 40(5), May 2013.

M.M. Adachi, M.P. Anantram, K.S. Karim, "Core-shell silicon nanowire solar cells," Scientific Reports, March 2013. (6 journal pages)

S. Abbaszadeh, N. Allec, and K.S. Karim, "Characterization of low dark-current lateral amorphous-selenium metal-semiconductor-metal photodetectors," Institute of Electrical and Electronics Engineering (IEEE) Sensors Journal, Vol. 13(5), pp. 1452-1458, May 2013.

S. Abbaszadeh, N. Allec, K.S. Karim, "Design and optimization of a high voltage metal-semiconductor-metal (MSM) photodetector," IEEE Sensors, February 2013. (6 journal pages)

M.M. Adachi, M.P. Anantram, K.S. Karim, "Core-shell silicon nanowire solar cells," Scientific Reports, March 2013. (6 journal pages)

S. Abbaszadeh, K.S. Karim, and V. Karanassios, "Measurement of UV from a microplasma by a microfabricated amorphous selenium detector," IEEE Trans. On Electron Devices, Vol. 60(2), pp. 880-883, February 2013.

2013 Conference Proceedings

S. Abbaszadeh, K.S. Karim, and V. Karanassios, "A microfabricated, low dark current amorphous selenium (a-Se) detector for measurement of microplasma optical emission in the ultraviolet UV for possible use on-site," in Society of photo-optical instrumentation engineers (SPIE) Next-generation. spectroscopic technologies VI., Baltimore, MD, April 2013.

S. Ghanbarzadeh, S. Abbaszadeh, M. Adachi, and K.S. Karim, "Low dark current and high dynamic range Hydrogenated amorphous silicon (a-Si:H) MSM photodetector for large area medical imaging," in SPIE medical imaging 2013: Physics of medical imaging, Orlando, FL, February 2013.

S. Abbaszadeh, Z. Du, N. Allec, and K.S. Karim, "Application of organic semiconductors in amorphous selenium based photodetectors for high performance x-ray imaging," in SPIE medical imaging 2013: Physics of medical imaging, Orlando, FL, February 2013.

Y. Fang, A. Badal, A. Badano, and K.S. Karim, "Spatial resolution characteristics of a-Se imaging detectors using Monte Carlo methods with detailed spatiotemporal transport of x-rays, electrons, and electron-hole pairs under applied bias," in SPIE medical imaging 2013: Physics of medical imaging, Orlando, FL, February 2013.

K-W Shin and K.S. Karim, "Fabrication and characterization of a novel x-ray silicon detector," in SPIE medical imaging 2013: Physics of medical imaging, Orlando, FL, February 2013.

R. Mann, I.A. Cunningham, and K.S. Karim, "Characterization of a digital x-ray detector for region of interest tuberculosis screening," in SPIE medical imaging 2013: Physics of medical imaging, Orlando, FL, February 2013.

2012 Book Chapters

Y. Fang, K.S. Karim, A. Badano, "Monte carlo modeling of x-ray detectors for medical imaging," in Semiconductor Radiation Detection Systems, Editor: Krzysztof Iniewski, in press, 2012.

2012 Journals

S. Abbaszadeh, K.S. Karim, V. Karanassios, "Measurement of UV from a microplasma by a microfabricated amorphous selenium detector," Institute of Electrical and Electronics Engineering (IEEE) Transactions on Electron Devices, vol. 99, December 2012. (4 journal pages)

G.P. Lindberg, R.E. Tallman, S. Abbaszadeh, K.S. Karim, J.A. Rowlands, A. Reznik, B.A. Weinstein, "Frustration of photocrystallization in amorphous selenium (a-Se) films and film-polymer structures near the glass transition," AIP Proceedings Journal, December 2012. (2 journal pages)

A. Goldan, O. Tousignant, K.S. Karim, J.A. Rowlands, "Solid-state charpak detector with unipolar time-differential pulse response," Applied Physics Letter, November 2012. (5 journal pages)

M.Y. Yazdandoost, and K.S. Karim, "Photon-quantum-noise-limited pixel architecture in amorphous-silicon technology for large-area digital imaging applications," IEEE Trans. On Electron Devices, Vol. 59(11), pp. 3017-3023, November 2012.

N. Allec, S. Abbaszadeh, A. Fleck, O. Tousignant, and K.S. Karim, "K-edge imaging using dual-layer and single-layer large area flat panel imagers," IEEE Trans. On Nucl. Science, Vol. 59(5), pp. 1856-1861, October 2012.

N. Allec, S. Abbaszadeh, C. Scott, J. Lewin, K.S. Karim, "Including the effect of motion artifacts in noise and performance analysis of dual-energy contrast-enhanced mammography," Journal of Physics in Medicine and Biology, Vol. 57, December 2012. 24 journal pages (double column, 10 pt font)

S. Abbaszadeh, N. Allec, S. Ghanbarzadeh, U. Shafique, and K.S. Karim, "Investigation of hole-blocking contacts for high-conversion-gain amorphous selenium detectors for x-ray imaging," IEEE Trans. On Electron Devices, Vol. 59(9), pp. 2403-2409, September 2012.

P.K. Singh, G. Chatterjee, A.D. Lad, A. Adak, S. Ahmed, M. Khorasaninejad, M.M. Adachi, K.S. Karim, S.S. Saini, A.K. Sood, G.R. Kumar, "Efficient generation and guiding of megaampere relativistic electron current by silicon nanowires," Applied Physics Letters, June 2012. (3 journal pages)

S. Abbaszadeh, K. Rom, O. Bubon, B. A. Weinstein, K.S. Karim, J.A. Rowlands, A. Reznik, "The effect of the substrate on transient photodarkening in stabilized amorphous selenium," Journal of Non-Crystalline Solids, doi:10.1016/j.jnoncrysol.2011.12.098, 2012. (4 journal pages)

Y. Fang, A. Badal, N. Allec, K.S. Karim, and A. Badano, "Spatiotemporal monte carlo transport methods in x-ray semiconductor detectors: Application to pulse-height spectroscopy in a-Se," Medical Physics, Vol. 39(1), pp. 308-319, January 2012.

2012 Conference Proceedings

S. Abbaszadeh, S.H. Majid, N. Allec, and K.S. Karim, "Amorphous selenium photodetector on a flexible substrate for indirect conversion medical imaging," in Society of photo-optical instrumentation engineers (SPIE) Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

K-W Shin, K. Wang, N. Allec, Y. Fang, and K.S. Karim, "Novel silicon x-ray detector with thin-film transistor (TFT) readout," in SPIE Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

N. Allec, S. Abbaszadeh, J.M. Lewin, and K.S. Karim, "Motion artifacts in dual-energy contrast-enhanced mammography," in SPIE Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

S. Abbaszadeh, N. Allec, and K.S. Karim, "High performance amorphous selenium lateral photodetector," in SPIE Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

Y. Fang, A. Badal, K.S. Karim, and A. Badano, "Spatio-temporal monte carlo modeling of a-Se detectors for breast imaging: energy-weighted Swank noise and detective quantum efficiency," in SPIE Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

S.H. Majid, K. Wang, N. Allec, U. Shafique, and K.S. Karim, "Characterization of gated selenium photo detector," in SPIE Medical Imaging 2012: Physics of Medical Imaging, San Diego, CA, February 2012.

2011 Book Chapters

M.M. Adachi, R. Khorasani, S. Saini, K.S. Karim, "Optical properties of silicon nanowires," in Optical Spectroscopy Tools for Nanoscience & Nanotechnology, Editor: Challa Kumar, in press, 2011.

2011 Journals

S. Abbaszadeh, N. Allec, K. Wang, and K.S. Karim, "Low dark-current lateral amorphous-selenium (a-Se) metal-semiconductor-metal photodetector," Institute of Electrical and Electronics Engineering (IEEE) Electron Device Lett., Vol. 32(9), pp. 1263-1265, September 2011.

D. Sharma, Y. Fang, F. Zafar, K.S. Karim, and A. Badano, "Recombination models for spatio-temporal monte carlo transport of interacting carriers in semiconductors," Appl. Phys. Lett., Vol. 98(24), June 2011.

K. Wang, F. Chen, N. Allec, F. Yuan, G. Belev, S. Kasap, K.S. Karim, "Amorphous-selenium-based three-terminal x-Ray detector with a gate," IEEE Electron Dev. Lett., Vol. 32(6), pp. 782-784, June 2011.

S. Kasap, J.B. Frey, G. Belev, O. Tousignant, H. Mani, J. Greenspan, L. Laperriere, O. Bubon, A. Reznik, G. DeCrescenzo, K.S. Karim, and J.A. Rowlands, "Amorphous and polycrystalline photoconductors for direct conversion flat panel x-ray image sensors," Sensors, Vol. 11(5), pp. 5112-5157, May 2011.

F. Chen, K. Wang, Y.A. Fang, N. Allec, G. Belev, S. Kasap, and K.S. Karim, "Direct-conversion x-ray detector using lateral amorphous selenium structure," IEEE Sensors Journal, Vol. 11(2), pp. 505-509, February 2011.

2011 Conference Proceedings

C. Hristovski, A. Goldan, S.H. Majid, K. Wang, U. Shafique, and K.S. Karim, "Characterization and comparison of lateral amorphous semiconductors with embedded Frisch grid detectors on 0.18m complementary metal oxide semiconductor (CMOS) processed substrate for medical imaging applications," in Society of photo-optical instrumentation engineers (SPIE) Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

K. Wang, M.Y. Yazdandoost, R. Keshavarzi, K-W Shin, C. Hristovski, S. Abbaszadeh, F. Chen, S.H. Majid, and K.S. Karim, "Integration of an amorphous silicon passive pixel sensor array with a lateral amorphous selenium detector for large area indirect conversion x-ray imaging applications," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

S. Abbaszadeh, N. Allec, K. Wang, F. Chen, and K.S. Karim, "Study of gain phenomenon in lateral metal-semiconductor-metal detectors for indirect conversion medical imaging," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

M.Y. Yazdandoost, K. Wang, K.S. Karim, "Photon quantum shot noise limited array in amorphous silicon technology for protein crystallography applications," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

S.H. Majid, A.H. Goldan, B. Hadji, G. Belev, S. Kasap, and K.S. Karim, "Selenium coated CMOS passive pixel array for medical imaging," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, Feb. 2011.

U. Shafique and K.S. Karim, "Lateral organic photodetectors for imaging applications," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

N. Allec, S. Abbaszadeh, and K.S. Karim," Analysis of multilayer and single layer x-ray detectors for contrast-enhanced mammography using imaging task," in SPIE Medical Imaging 2011: Physics of Medical Imaging, Orlando, FL, February 2011.

2010 Journals

M.H. Izadi, O. Tousignant, M.F. Mokam, and K.S. Karim, "An amorphous-silicon (a-Si) active pixel sensor (APS) Array for medical x-ray imaging," Institute of Electrical and Electronics Engineering (IEEE) Trans. On Electron Dev., Vol. 57(11), pp. 3020-3026, November 2010.

K. Wang, F. Chen, N. Allec, and K.S. Karim, "Fast lateral amorphous-selenium (a-Se) metal-semiconductor-metal photodetector with high blue-to-ultraviolet responsivity," IEEE Trans. On Electron Dev., Vol. 57(8), pp. 1953-1958, August 2010.

K. Wang and K.S. Karim, "Silicon x-ray detector with integrated thin-film transistor for biomedical applications," IEEE Electron Dev. Lett., Vol. 31(2), pp. 147-149, February 2010.

A. Sultana, M.M. Wronski, K.S. Karim, and J.A. Rowlands, "Digital x-ray imaging using avalanche a-Se photoconductor," IEEE Sensors Journal, Vol. 10(2), pp. 347-352, February 2010.

2010 Conference Proceedings

M.Y. Yazdandoost, D. Wu, and K.S. Karim, "Pixel electronic noise as a function of position in an active matrix flat panel imaging array," in Society of photo-optical instrumentation engineers (SPIE) Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

A.H. Goldan, K. Wang, F. Chen, and K.S. Karim, "Amorphous selenium lateral Frisch photodetector and photomultiplier for high performance medical x-ray and gamma-ray imaging applications," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

M.H. Izadi, O. Tousignant, M.F. Mokam, M. Yazdandoost, N. Safavian, H. Mani, L. Laperriere, and K.S. Karim, "Performance of a prototype amorphous silicon active pixel sensor array using a-Se for direct x-ray conversion," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

M.Y. Yazdandoost, K.W. Shin, N. Safavian, F. Taghibakhsh, and K.S. Karim, "Photon counting pixel and array in amorphous silicon technology for large area digital medical imaging applications," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

N. Safavian, M. Yazdandoost, D. Wu, M.H. Izadi, K.S. Karim, and J.A. Rowlands, "Investigation of gain non-uniformities in the two thin-film transistor (TFT) current programmed amorphous silicon active pixel sensor for fluoroscopy, chest radiography, and mammography tomosynthesis applications," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

M.M. Adachi, K. Wang, F. Chen, and K.S. Karim, "Silicon nanowire metal-semiconductor-metal photodetectors," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

K. Wang, F. Chen, K-W Shin, N. Allec, and K.S. Karim, "Lateral amorphous selenium metal-semiconductor-metal photodetector for large-area high-speed indirect-conversion medical imaging applications," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

K-W Shin, K. Wang, A. Reznic, and K.S. Karim, "Cadmium zinc telluride detector for low photon energy applications," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

N. Allec, A.H. Goldan, K. Wang, F. Chen, and K.S. Karim, "Amorphous silicon p-i-n photodetector with Frisch grid for high-speed medical imaging," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

D. Wu, N. Safavian, M.Y. Yazdandoost, M.H. Izadi, and K.S. Karim, "Electronic noise comparison of amorphous silicon current mode and voltage mode active pixel sensors for large area digital x-ray imaging," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

N. Allec and K.S. Karim, "Multilayer x-ray detector for contrast-enhanced digital subtraction mammography," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

Y. Fang, A. Badal, N. Allec, K.S. Karim, and A. Badano, "Monte carlo simulation of amorphous selenium imaging detectors," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

N. Allec and K.S. Karim, "A balanced filterless K-edge energy window multilayer detector for dual energy computed tomography," in SPIE Medical Imaging 2010: Physics of Medical Imaging, San Diego, CA, February 2010.

2009 Journals

K. Wang, F. Chen, G. Belev, S. Kasap, and K.S. Karim, "Lateral metal-semiconductor-metal photodetectors based on amorphous selenium (a-Se)," Appl. Phys. Lett., Vol. 95(1), July 2009.

F. Taghibakhsh, K.S. Karim, G. Belev, and S.O. Kasap, "X-ray detection using a two-transistor active pixel sensor array coupled to an a-Se x-ray photoconductor," Institute of Electrical and Electronics Engineering (IEEE) Sensors Journal, Vol. 9(1-2), January-February 2009.

2009 Conference Proceedings

K. Wang, F. Chen, G. Belev, S.O. Kasap, and K.S. Karim, "Design and modeling of a lateral a-Se metal-semiconductor-metal (MSM) photoconductor as indirect conversion x-ray imager," in Society of photo-optical instrumentation engineers (SPIE) Hard x-ray, gamma-ray, and neutron detector Physics XI, San Diego, CA, August 2009.

K. Wang, A. Reznik, and K.S. Karim, "Fabrication and characterization of cerium oxide thin films for ultraviolet sensing applications," in SPIE Optical Materials and Structures Technologies IV, San Diego, CA, August 2009.

F. Taghibaksh, D.M. Hunter, K.S. Karim, G. Belev, S.O. Kasap, V. Verpakhovski, and M.J. Yaffe, "Evaluation of the x-ray response of amorphous selenium coated 100μ pitch amorphous silicon (a-Si) active pixel sensors for tomosynthesis applications," in SPIE Medical Imaging 2009: Physics of Medical Imaging, Orlando, FL, February 2009.

N. Safavian, M. Yazdandoost, D. Wu, A. Sultana, M.H. Izadi, K.S. Karim, A. Nathan, and J.A. Rowlands, "Characterization of current programmed amorphous silicon active pixel sensor readout circuit for dual mode diagnostic digital x-ray imaging," in SPIE Medical Imaging 2009: Physics of Medical Imaging, Orlando, FL, February 2009.

A. Sultana, N. Safavian, M.H. Izadi, K.S. Karim, and J.A. Rowlands, "Characterization of bias induced metastability of amorphous silicon thin film transistor based passive pixel sensor switch and its impact on biomedical x-ray imaging application," in SPIE Medical Imaging 2009: Physics of Medical Imaging, Orlando, FL, February 2009.

A.H. Goldan, B. Hadji, K.S. Karim, G. DeCrescenzo, J.A. Rowlands, O. Tousignant, and L. Laperriere, "A counting and integrating pixel readout chip for amorphous selenium direct radiation detectors for medical imaging applications," in SPIE Medical Imaging 2009: Physics of Medical Imaging, Orlando, FL, February 2009.

A.H. Goldan, Y. Fang, K.S. Karim, O. Tousignant, H. Mani, and L. Laperriere, "Amorphous selenium detector utilizing a Frisch grid for photon-counting imaging applications," in SPIE Medical Imaging 2009: Physics of Medical Imaging, Orlando, FL, February 2009.

2008 Book Chapters

K.S. Karim, "Active matrix flat panel imagers for diagnostic medical imaging applications," in Electronics for Medical Imaging, Editors: Kris Iniewski, Wiley, 2008, May 2008. 25 pages text (12,000 words), 17 figures.

2008 Journals

F. Taghibakhsh, I. Khodami, K.S. Karim, "Characterization of short wavelength selective a-Si:H metal-semiconductor-metal (MSM) photoconductors for large area digital imaging applications," Institute of Electrical and Electronics Engineering (IEEE) Transactions on Electron Devices, 55(1), pp. 337-342, January 2008

K.S. Karim, I. Khodami, F. Taghibakhsh, "a-Si:H (MSM) photoconductor detector for biomolecular imaging applications," ECS Transactions, February 2008, in press.

F. Taghibakhsh, K.S. Karim, "Two-transistor active pixel sensor readout circuits in amorphous silicon (a-Si) technology for high resolution digital imaging applications ," IEEE Transactions on Electron Devices, vol. 55, no. 8, pp. 2121-2128, August 2008.

F. Taghibakhsh, K.S. Karim, "Charge-gated thin film transistors for high resolution digital imaging applications," IEEE Electron Device Letters, vol. 29, no. 8, pp. 859-862, August 2008.

M.M. Adachi, K. Kavanagh, K.S. Karim, "Structural and electrical characteristics of nanocrystalline silicon prepared by hot-wire chemical vapor deposition on polymer substrates," Thin Solid Films, Volume 516, Issue 21, Pages 7418-7421, September 2008.

I. Khodami, F. Taghibakhsh, K.S. Karim, "UV Enhanced a-Si:H MSM," IEEE Electron Device Letters, Vol. 29, no. 9, pp. 1007-9, September 2008.

F. Taghibakhsh, K.S. Karim, G. Belev, S.O. Kasap, "X-ray detection using a two-transistor amplified pixel sensor array coupled to an amorphous selenium (a-Se) x-ray photoconductor," IEEE Sensors, accepted June 2008, in press.

A. Sultana, K.S. Karim, A. Reznik, J.A. Rowlands, "Design and feasibility of active matrix flat panel detector using avalanche amorphous selenium for protein crystallography," Medical Physics, accepted July 2008, in press.

A. Sultana, K.S. Karim, J.A. Rowlands, "Avalanche selenium detector for protein crystallography," IEEE Canadian Journal of Electrical and Computer Engineering, accepted September 2008, in press.

2008 Conference Proceedings

S. Tsang, A.H. Ma, K.S. Karim, M. Parameswaran, A.M. Leung, "Monolithically fabricated polymer MEMS 3-AXIS thermal accelerometers designed for automated wirebonder assembly," IEEE 21st International Conference on MEMS, Tucson, USA, January 2008.

A. Goldan, K.S. Karim, A. Reznik, C.B. Caldwell, J.A. Rowlands, "Photon counting readout pixel array in 0.18-um complementary metal oxide semiconductor (CMOS) technology for on-line gamma-ray imaging of 103 palladium seeds for permanent breast seed implant (PBSI) brachytherapy," in Society of photo-optical instrumentation engineers (SPIE) Medical Imaging 2008: Physics of Medical Imaging, San Diego, USA, February 2008, in press.

F. Taghibakhsh, K.S. Karim, "High resolution amplified pixel sensor architectures for large area digital mammography tomosynthesis," in SPIE Medical Imaging 2008: Physics of Medical Imaging, San Diego, USA, February 2008, in press. Honourable mention poster award.

F. Taghibakhsh, K.S. Karim, "Light controlled oscillator: A pixel architecture for large area digital imaging using amorphous silicon," IEEE Canadian Conference on Electrical and Computer Engineering, March 2008, in press.

A. Sultana, K.S. Karim, J.A. Rowlands, "Large area direct x-ray conversion detector for protein crystallography," IEEE Canadian Conference on Electrical and Computer Engineering, March 2008, in press. Best student paper award.

K.S. Karim, I. Khodami, F. Taghibakhsh, "a-Si:H metal-semiconductor-metal (MSM) photoconductor detector for biomolecular imaging applications," 213th meeting of the electrochemical society (Dielectrics for Nanosystems III session), Phoenix, USA, May 2008. Invited.

A. Goldan, K.S. Karim, "Unipolar charge sensing using frisch and coplanar grid techniques for amorphous aelenium based radiation detectors," SPIE Optics and Photonics 2008: Hard X-Ray, Gamma-Ray, and Neutron Detector Physics X, San Diego, CA, August 2008.

N. Safavian, K.S. Karim, A. Nathan, J.A. Rowlands, "A 3-thin-film transistor (TFT) hybrid active-passive pixel with correlated double sampling CMOS readout circuit for real-time medical x-ray imaging," 34th European Solid-State Circuits Conference (ESSCIRC), September 2008.

2007 Journals

G. Sanaie, K.S. Karim, "On-pixel voltage controlled oscillator in amorphous silicon technology for digital imaging applications," Institute of Electrical and Electronics Engineering (IEEE) Electron Device Letters, 28(1), pp. 33-35, January 2007.

F. Taghibakhsh, K.S. Karim, "High dynamic range 2-thin-film transistor (TFT) amplified pixel sensor architecture for digital mammography tomosynthesis," IEE Proceedings On Circuits, Devices and Systems, 1(1), pp. 87-92, February 2007.

M.M. Adachi, K. Kavanagh, K.S. Karim, "Structural and electrical characteristics of microcrystalline silicon prepared by hot-wire chemical vapour deposition using a graphite filament," J. Vac. Sci. Tech. A, 25(3), pp. 464-467, May 2007.

M.H. Izadi, K.S. Karim, "Noise optimisation analysis of an active pixel sensor for low-noise real-time X-ray fluoroscopy," IEE Proceedings On Circuits, Devices and Systems, 1(3), pp. 251-256, June 2007.

K.S. Karim, M.H. Izadi, F. Taghibakhsh, G. Sanaie, "Intelligent pixel architectures for digital medical imaging applications," ECS Transactions, 8(1), pp. 289-293, July 2007.

2007 Conference Proceedings

A. Goldan, L. Ng, J.A. Rowlands, K.S. Karim, "Photon counting pixel architecture for x-ray and gamma-ray imaging applications," in Society of photo-optical instrumentation engineers (SPIE) Medical Imaging 2007: Physics of Medical Imaging, SPIE vol. 6510, February 2007.

F. Taghibakhsh, K.S. Karim, "Amplified Pixel Sensor Architectures for Low Dose Computed Tomography using Silicon Thin Film Technology," in SPIE Medical Imaging 2007: Physics of Medical Imaging, SPIE vol. 6510, February 2007 Honourable mention poster award.

F. Taghibakhsh, M.M. Adachi, K.S. Karim, "Hot-wire deposited nanocrystalline silicon thin-film transistors (TFTs) on plastic substrates" 2007 Spring Materials Research Society Symposium, San Francisco, USA, April 2007.

M.M. Adachi, F. Taghibakhsh, K. Kavanagh, K.S. Karim, "Structural analysis of nanocrystalline silicon prepared by hot-wire chemical vapor deposition (CVD) on polymer substrates" 2007 Spring Materials Research Society Symposium, San Francisco, USA, April 2007.

F. Taghibakhsh, K.S. Karim, "Fabrication and characterization of nickel-amorphous silicon metal-semiconductor-metal photoconductors," in 2007 Canadian Conference on Electrical and Computer Engineering (CCECE), Vancouver, Canada, April 2007.

W.F.L.Tse, I. Khodami, M. M. Adachi, X. Wang, K. Kavanagh, K.S. Karim, "Characterization of low temperature P-Type hydrogenated microcrystalline silicon thin films deposited by plasma enhanced chemical vapor deposition," Proc. 2007 Canadian Conference on Electrical and Computer Engineering (CCECE), pp. 952-955, April 2007.

M.H. Izadi, K.S. Karim, "Noise optimization of an active pixel sensor for real-time digital x-ray fluoroscopy," noise and fluctuations in circuits, devices, and materials, Eds. Massimo Macucci, Lode K.J. Vandamme, Carmine Ciofi, Michael B. Weissman, Proc. SPIE, Vol. 6600, May 2007.

K.S. Karim, M.H. Izadi, F. Taghibakhsh, G. Sanaie, "Intelligent pixel architectures for digital imaging applications," 2007 ultra large-scale integration (ULSI) vs. thin-film transistor (TFT): International conference on semiconductor technology for ultra large scale integrated circuits and thin film transistors, Barga, Italy, July 2007 Invited.

M.M. Adachi, K.S. Karim, "Thin film silicon solar cells prepared by temperature controlled hot-wire chemical vapor deposition," 2007 IEEE 5th world conference on photovoltaic energy conversion, Fukuoka, Japan, August 2007.

F. Taghibakhsh, K.S. Karim, "Two transistor active pixel sensor for high resolution large area digital x-ray imaging," IEEE International Electron Devices Meeting (IEDM) Technical Digest, December 2007.

2006 Journals

K.S. Karim, G. Sanaie, T. Ottaviani, M.H. Izadi, F. Taghibakhsh, "Amplified pixel architectures in amorphous silicon technology for large area digital imaging applications," Journal of Korean Physical Society, vol. 48(1), February 2006.

A.H. Goldan, K.S. Karim, J.A. Rowlands, "Single photon counter for digital x-ray mammography tomosynthesis," Journal of Vacuum Science and Technology A, 24(3), pp 854-859, May 2006.

T. Ottaviani, K.S. Karim, A. Nathan, J.A. Rowlands, "A low noise circuit solution that permits a higher output signal-to-noise ratio (SNR) for current mediated active pixel sensors," Journal of Vacuum Science and Technology A, 24(3), pp 770-773, May 2006.

M.H. Izadi, K.S. Karim, "High dynamic range pixel architecture for advanced diagnostic medical X-ray imaging applications," Journal of Vacuum Science and Technology A, 24(3), pp 846-849, May 2006.

Taghibakhsh, K.S. Karim, "Low leakage Hydrogenated amorphous silicon (a-Si:H) thin film transistors deposited on glass substrates using hot wire chemical vapor deposition," J. Vac. Sci. Tech. A, 24(3), pp 866-868, May 2006.

2006 Conference Proceedings

G.H. Chapman, M.L. La Haye, C. Jung, M.H. Izadi, K.S. Karim, "Noise analysis of fault tolerant active pixel sensors with and without defects" Proc. Society of photo-optical instrumentation engineers (SPIE): Sensors, cameras, and systems for scientific and industrial applications VII; Morley M. Blouke; Ed. Vol. 6068, pp. 26-36, February 2006.

A.H. Goldan, K.S. Karim, J.A. Rowlands, "Selective photon counter for digital x-ray mammography tomosynthesis," in SPIE Medical Imaging 2006: Physics of Medical Imaging, Proc. SPIE, Vol. 6142, pp. 1697-1705, February 2006. Honourable mention poster award.

M.H. Izadi, K.S. Karim, A. Nathan, J.A. Rowlands, "Low-noise pixel architectures for advanced diagnostic medical x-ray imaging applications," in SPIE Medical Imaging 2006: Physics of Medical Imaging, Proc. SPIE Vol. 6142, pp. 264-274, February 2006.

I. Khodami, M.M. Adachi, M. Malhotra, F. Taghibakhsh, K.S. Karim, K. Kavanagh, J.A. Rowlands, "Light induced degradation in amorphous silicon photodiodes and implications for diagnostic medical imaging applications," in SPIE Medical Imaging 2006: Physics of Medical Imaging, Eds. Vol. 6142, pp. 967-975, February 2006.

F. Taghibakhsh, K.S. Karim, "Hot-wire chemical vapor deposition (HWCVD) a-Si:H thin-film transistor (TFT) on plastic substrates," in Proc. 2006 Materials Research Society Symposium, San Francisco, USA, April 2006.

M.M. Adachi, L. Tse, K.S. Karim, K. Kavanagh, "Effects of HWCVD-deposited seed layers on hydrogenated microcrystalline silicon films on glass substrates," 2006 Materials Research Society Symposium, San Francisco, USA, April 2006.

M.M. Adachi, W.F. Tse, K.S. Karim, "Low temperature microcrystalline silicon solar cells using hot-wire chemical vapor deposition," Proc. 2006 Institute of Electrical and Electronics Engineering (IEEE) 4th World Conference on Photovoltaic Energy Conversion, Vol 2, pp. 1632 - 1634, May 2006.

I. Khodami, M.M. Adachi, K. Kavanagh, K S. Karim, "Wavelength selective amorphous silicon photodiodes for biomedical applications," 29th Canadian medical and biological engineering conference, Vancouver, BC, June 2006.

M.H. Izadi, D.T. Ressl, K.S. Karim, "Low-noise design and testing methodology for an amorphous-silicon (a-Si) flat-panel medical x-ray imager," 29th Canadian medical and biological engineering conference, Vancouver, BC, Oral presentation, in press, June 2006. Best student paper award.

K.S. Karim, G. Sanaie, F. Taghibakhsh, "Amorphous silicon pixel-level voltage controlled oscillator for digital imaging applications," 210th meeting of the Electrochemical Society (Integrated Optoelectronics session), Cancun, Mexico, October 2006. Invited.

A.H. Goldan, K.S. Karim, "Imaging for placement of radioactive palladium seeds for breast cancer treatment," Canadian microelectronics corporation (CMC) microsystems 2006 annual symposium (TEXPO), October 2006. $3000 CMC industrial collaboration award.

Older Book Chapters

K.S. Karim, A. Nathan, "Large area digital photon imaging," in Microelectromechanical systems (MEMS): A practical guide to design, analysis and applications, Editors: Jan G. Korvink, Oliver Paul, 992 pages, ISBN: 0-8155-1497-2, December 2005.

A. Nathan, P. Servati, K. S. Karim, A. Sazonov, and D. Stryahilev, "Hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs) on glass and plastic," in a-Si:H Thin Film Transistors, Y. Kuo, Editor, Thin Film Transistors: Materials and processes, Kluwer Academic Publishers, ISBN 1402075049, 1000 pages, September 2003.

S. Tao, K.S. Karim, P. Servati, A. Nathan, "Large area digital x-ray imaging," in sensors, Update 10: Sensors technology - applications - markets, H. Baltes, G.K. Fedder, G. Korvink, Editors, Wiley-VCH Verlag GmbH, ISBN: 3527303618, 312 pages, April 2002. Book Chapters.

Older Journals

K.S. Karim, A. Nathan, "Noise performance of a current-mediated amplified pixel for medical imaging," Journal of Vacuum Science and Technology A, vol. 22, pp. 1010-1014, 2004.

K.S. Karim, A. Nathan, M. Hack, W. Milne, "Drain-bias dependence of threshold voltage stability of amorphous silicon TFTs," Institute of Electrical and Electronics Engineering (IEEE) Electron Device Letters, 25(4), pp. 188-190, April 2004.

K.S. Karim, P. Servati, A. Nathan, "High voltage amorphous silicon TFT for use in large area applications," Microelectronics Journal, 35(3), pp. 311-315, March 2004.

L. Stamenic, E. Smiley, K.S. Karim, "Low light conditions modelling for building integrated photovoltaic (BIPV) systems," Solar Energy, v. 77, pp. 37-45, Mar 2004.

A. Nathan, A. Kumar, K. Sakariya, P. Servati, K.S. Karim, D. Striakhilev, A. Sazonov, "Amorphous silicon back-plane electronics for organic light-emitting diode (OLED) displays," IEEE Journal of Selected Topics in Quantum Electronics, vol. 10, pp. 58-69, Feb 2004.

K.S. Karim, A. Nathan, J.A. Rowlands, S.O. Kasap, "X-ray detector with on-pixel amplification for large area diagnostic medical imaging," IEEE Proceedings on Circuits, Devices and Systems, 150(4), pp. 267-273, August 2003.

A. Kumar, K. Sakariya, P. Servati, S. Alexander, D. Striakhilev, K.S. Karim, A. Nathan, M. Hack, E. Williams, G.E. Jabbour, "Design considerations for active matrix organic light emitting diode arrays," IEEE Proceedings on Circuits, Devices and Systems, 150(4), pp. 322-328, August 2003.

A. Nathan, P. Servati, K.S. Karim, D. Striakhilev, A. Sazonov, "Thin film transistor integration on glass and plastic substrates in amorphous silicon technology," IEEE Proceedings on Circuits, Devices and Systems, 150(4), pp. 329-338, August 2003.

P. Servati, K.S. Karim, A. Nathan, "Static characteristics of a-Si:H Dual-Gate TFTs," IEEE Transactions on Electron Devices, 50(4), pp. 926-932, April 2003.

K.S. Karim, A. Nathan, J.A. Rowlands, "Amorphous silicon active pixel sensor readout circuit for digital imaging," IEEE Transactions on Electron Devices: Special Issue on Image Sensors, 50(1), pp.200-208, January 2003.

N. Mohan, K.S. Karim, A. Nathan, "Design of multiplexer in amorphous silicon technology," J. Vacuum Sci Tech A, 20(3), pp. 1043-1047, May 2002.

K.S. Karim, A. Nathan, J.A. Rowlands, "Active pixel sensor architectures in a-Si:H for medical imaging," J. Vacuum Sci Tech A, 20(3), pp. 1095-1099, May 2002.

K.S. Karim, A. Nathan, J.A. Rowlands, "Amorphous silicon active pixel sensor architectures for large area medical imaging," Journal of Non-Crystalline Solids, 299-302, Part 2, pp. 1250-1255, April 2002.

K.S. Karim, A. Nathan, "Readout circuit in active pixel sensors in amorphous silicon technology," IEEE Electron Device Letters, 22(10), pp. 469-471, October 2001.

A. Nathan, B. Park, A. Sazonov, S. Tao, I. Chan, P. Servati, K. Karim, T. Charania, D. Striakhilev, Q. Ma, and R.V.R. Murthy, "Amorphous silicon detector and thin film transistor technology for large area imaging of x-rays," Microelectronics Journal, vol. 31, No. 11-12, pp. 883-891, October 2000.

B. Park, K.S. Karim, A. Nathan, "Intrinsic thin film stresses in multi-layered imaging pixels," Journal of Vacuum Science and Technology A, 18(2), pp. 688-692, March 2000.