Faculty

Ching W. Tang

Professor of Chemical Engineering
Professor of Chemistry

PhD, Cornell University, 1975

101A Gavett Hall
(585) 275-3552
Fax: (585) 273-1348
ching.tang@rochester.edu

Website

Biography

Selected Honors & Awards

Nick Holonyak Jr. Award by The Optical Society (2014)
Eduard Rhein Technology Award (2013)
Wolf Prize in Chemistry (2011)
Honorary Doctorate, Shanghai University (2010)
Lifetime Achievement Award, University of Rochester (2010)
Daniel E. Noble Award, IEEE (2007)
Member of the U.S. National Academy of Engineering (2006)
Humboldt Research Award, Humboldt Foundation, Germany (2005)
American Chemical Society Award for Team Innovation (2003)
Fellow, Society for Information Display (2002)
Inventor of the Year Award, Rochester Intellectual Property Law Association (2002)
Jan Rajchman Prize, Society for Information Display (2001)
Carothers Award, American Chemical Society (2001)
Northeast Regional Industrial Innovation Award, American Chemical Society (2001)
Eastman Innovation Award, Eastman Kodak Company (2000)
Fellow, American Physical Society (1998)

Research Overview

Our research is focused on two areas: (1) developing high-efficiency and low-cost solar cells, and (2) advancing the technology of organic light emitting diode (OLED) for display and lighting applications. We fabricate thin-film devices using a suite of vacuum deposition and solution process tools, including vapor deposition of multi-component amorphous organic thin films and close-space sublimation of II-VI semiconductors at high temperature to form crystalline films. We design device architectures - planar, bulk, and graded heterojunctions of organic donors and acceptors - for mediating charge generation, recombination, and transport in OLEDs and organic solar cells. We develop low-impedance contacts for electron and hole injections into semi-insulating materials. Our interest in solar cell work includes the development of methods for fabricating high-efficiency CdS/CdTe solar cells with ultra-thin CdTe films, aiming at significant reduction in material usage. We are also interested in further improving organic solar cell efficiency through design of novel device architectures and material compositions. Another major research effort is to advance OLED technology. Specifically we focus on developing highly stable and efficient white emitters for lighting applications, including light-scattering layers for enhanced light extraction.

Selected Publications

  • Lin, H., Irfan, Xia, W., Wu, H. N., Gao, Y., Tang, C. W. "MoOx back contact for CdS/CdTe thin film solar cells: preparation, device characteristics, and stability," Solar Energy Materials and Solar Cells 2012, 99, 349-355.
  • Irfan, Xia, W., Lin, H., Ding, H., Tang, C. W., Gao, Y., "Nitric-phosphoric acid etching effects on the surface chemical composition of CdTe thin film," Thin Solid Films 2012, 520, 1988-1992.
  • Zhang, M., Wang, H., Tang, C. W. "Tandem photovoltaic cells based on low-concentration donor doped C60," Organic Electronics 2011, 13, 249-251.
  • Zhang, M., Wang, H., Tang, C. W. "Hole-transport limited S-shaped I-V curves in planar heterojunction organic photovoltaic cells," Appl. Phys. Lett. 2011, 99, 213506.
  • Lee, S. M., Tang, C. W. "Fabrication of a blue organic light-emitting diode with a novel thermal deposition boat," J. Vac. Sci. Technol. B 2011, 29, 062401.
  • Zhang, M., Wang, H., Tian, H., Geng, Y., Tang, C. W. "Bulk heterojuction photovoltaic cells with low donor concentration," Adv. Mat. 2011, 23, 4960-4964.
  • Glowacki, E. D., Marshall, K. L., Tang, C. W., Sariciftci, N. S. "Doping of organic semiconductors induced by lithium fluoride/aluminum electrodes studied by electron spin resonance and infrared reflection-absorption spectroscopy," Appl. Phys. Lett. 2011, 99, 043305.
  • Xia, W., Lin, H., Wu, H. N., Tang, C. W. "Effects of high temperature annealing on ultra-thin CdTe solar cells," Thin Solid Films 2011, 520, 563-568.
  • Irfan; Zhang, M.; Ding, H.; Tang, C. W.; Gao, Y. “Strong Interface p-Doping and Band Bending in C60 on MoOx,” Organic Electronics 2011, 12, 1588–1593.
  • Zhang, M.; Wang, H.; Tian, H.; Geng, Y.; Tang, C. W. “Bulk Heterojuction Photovoltaic Cells with Low Donor Concentration,”Advanced Materials 2011, 23, 4960-4964.
  • Glowacki, E. D.; Marshall, K. L.; Tang, C. W.; Sariciftci, N. S. “Doping of Organic Semiconductors Induced by Lithium Fluoride/Aluminum Electrodes Studied by Electron Spin Resonance and Infrared Reflection-Absorption Spectroscopy,” Applied Physics Letters 2011 99, 043-305.
  • Xia, W.; Lin, H.; Wu, H. N.; Tang, C. W. “Effects of High Temperature Annealing on Ultra-thin CdTe Solar Cells,” Thin Solid Films 2011, 520, 563-568.
  • Kaji, T.; Zhang, M.; Nakao, S.; Iketaki, K.; Yokoyama, K.; Tang, C. W.; Hiramoto, M. “Co-evaporant Induced Crystalline Donor: Acceptor Blends in Organic Solar Cells Effect,” Advanced Materials 2011, 23, 3320-3325.
  • Zhang, M., Wang, H., Tang, C. W. "Effect of the highest occupied molecular orbital energy level offset on organic heterojunction photovoltaic cells," Appl. Phys. Lett. 2010, 97, 143503.
  • Lin, H., Xia, W., Wu, H. N., Tang, C. W. "CdS/CdTe solar cells with MoOx as back contact buffers," Appl. Phys. Lett. 2010, 97, 123504.
  • Xia, W., Welt, J. A., Lin, H., Wu, H. N., Ho, M. H., Tang, C. W. "Fabrication of Cd1-xZnxS films with controllable zinc doping using a vapor zinc chloride treatment," Solar Energy Materials and Solar Cells 2010, 94, 2113-2118.
  • Glowacki, E., Horovitz, K., Tang, C. W., Marshall, K. L. "Photoswitchable Gas Permeation Membranes Based on Liquid Crystals," Adv. Funct. Mat. 2010, 20, 2778-2785.
  • Zeng, L., Tang, C. W., Chen, S. H. "Effects of active layer thickness and thermal annealing on polythiophene. Fullerene bulk heterojunction photovoltaic devices," Appl. Phys. Lett. 2010, 97, 053305.
  • Ho, M., Liu, M., Lin, K., Chen, C. H., Tang, C. W. "Efficient single-layer small molecule blue OLEDs based on a multifunctional bipolar transport material," Digest of Technical Papers - Society for Information Display International Symposium 2010, 41, 552-555.
  • Zhang, M., Irfan, Ding, H., Gao, Y., Tang, C. W. "Organic Schottky barrier photovoltaic cells based on MoOx/C60," Appl. Phys. Lett. 2010, 96, 183301.
  • Liao, L. S., Klubek, K. P., Madathil, J. K., Tang, C. W., Giesen, D. J. "Recoverable electroluminescence from a contaminated organic/organic interface in an organic light-emitting diode," Appl. Phys. Lett. 2010, 96, 043302.
  • Glowacki, E., Marshall, K. L., Tang, C. W. "Photoswitchable gas permeation membranes based on azobenzene-doped liquid crystals," Proceedings of SPIE (Liquid Crystals XIII) 2009, 7414.
  • Rajeswaran, M., Blanton, T.N., Tang, C.W. et al, "Structural, thermal, and spectral characterization of the different crystalline forms of Alq(3), tris(quinolin-8-olato)aluminum(III), an electroluminescent material in OLED technology," Polyhedron 2009, 28, 835-843.
  • Wang, H., Klubek, K. P., and Tang, C. W. "Current Efficiency in organic light emitting diodes with a hole-injecting layer," Appl. Phys. Lett. 2008, 93, 093306.
  • Liao, L. S. and Tang, C. W. "Moisture exposure to different layers in organic light-emitting diodes and the effect on electroluminescence characteristics," J. Appl. Phys. 2008, 104, 044501.
  • Wang, H., Klubek, K. P. and Tang, C. W. "Current efficiency in organic light-emitting diodes with a hole-injection layer," Appl. Phys. Lett. 2008, 93, 093306.
  • Wallace, J. U., Young, R. H., Tang, C. W. and Chen, S. H. "Charge-retraction time-of-flight measurement for organic charge transport materials," Appl. Phys. Lett. 2007, 91, 152104.
  • Chen, A. C. A., Wallace, J. U., Klubek, K. P., Madaras, M. B., Tang, C. W. and Chen, S. H. "Device characteristics of organic light-emitting diodes comprising terfluorene modified with triphenyltriazine," Chem. Mater. 2007, 19, 4043-4048.
  • Culligan, S. W., Chen, A. C. A., Wallace, J. U., Klubek, K. P., Tang, C. W. and Chen, S. H. "Effect of hole mobility through emissive layer on temporal stability of blue organic light-emitting diodes," Adv. Funct. Mater. 2006, 16, 1481-1487.
  • Liao, L. S., Klubek, K. P., Tang, C. W. "High-Efficiency Tandem Organic Light Emitting Diodes," Appl. Phys. Lett. 2004, 84, 167.
  • Yan, Li, Watkins, N. J., Tang, C. W., Yongli Gao "Fermi Level Pinning in CS doped CuPc," Synthetic Metals 2003, 137, 1037.
  • Tang, C. W., Van Slyke, S. A., Chem, C. H. " Electroluminescence of Doped Thin Films," J. Appl. Phys. 1989, 65, 3610.
  • Tang, C. W., Van Slyke, S. A. "Organic Electroluinescent Diodes," Appl. Phys. Lett. 1987, 51, 913.
  • Tang, C. W. "Two Layer Organic Photovoltaic Cell," Appl. Phys. Lett. 1986, 48, 183.