B.S. ​Applied Physics 1st class honors; Dublin City University, 2004Ph.D. ​Physical Sciences; Dublin City University, 2009

"Our work investigates the interfaces that are critical to the functionality and performance of nanoelectronic devices."

Stephen J. McDonnell, Assistant Professor

Stephen McDonnell’s current research interests are centered interfaces relevant to next generation nanoelectronics devices. This includes metal and insulator interfaces with ultra-wide-band gap Diamond and also the integration of 2D materials into device architectures involving interfaces with 3D materials. Device applications for these materials include photovoltaics, logic, low powered transistors, interconnects, RF applications, flexible electronics, thermoelectrics, and photoelectrochemistry. The McDonnell group carries out in-vacuo synthesis and interface formation couple with studies of electronic structure by in-vacuo photoelectron spectroscopy techniques, including XPS and APRES. The group correlates processing conditions with resultant materials structure and interface chemistry while engaging in collaborations to investigate how this impacts device relevant properties, such as contact resistance, thermal boundary conductance, photocurrents, and ZT. McDonnell is also currently investigating the anti-viral properties of copper-based alloys. In this work, he correlates the surface chemistry with corrosion behavior and anti-viral efficacy.

Research Interests

  • Electronic Material Integration
  • Nanoelectronics and 2-D Materials
  • Surface and Interface Science and Engineering
  • Energy Conconversion
  • Nanomaterials and nanomanufacturing

Selected Publications

  • The growth of self-intercalated Nb1+ xSe2 by molecular beam epitaxy: The effect of processing conditions on the structure and electrical resistivity ABS Peter M Litwin, Samantha T Jaszewski, Wendy L Sarney, Asher C Leff, Sergiy Krylyuk, Albert V Davydov, Jon F Ihlefeld, Stephen J McDonnell
  • Influence of Oxygen Dopants on the HER Catalytic Activity of Electrodeposited MoOxSy Electrocatalysts ABS Lee Kendall, Amir Chamaani, Zachary Piontkowski, Thomas E Beechem, Mackenzie Ridley, Elizabeth J Opila, Giovanni Zangari, Stephen J McDonnell
  • WSe2 growth on hafnium zirconium oxide by molecular beam epitaxy: the effect of the WSe2 growth conditions on the ferroelectric properties of HZO ABS Maria Gabriela Sales, Shelby Fields, Samantha Jaszewski, Sean Smith, Takanori Mimura, Wendy L Sarney, Sina Najmaei, Jon F Ihlefeld, Stephen McDonnell
  • Titanium contacts to graphene: process-induced variability in electronic and thermal transport ABS Keren M Freedy, Ashutosh Giri, Brian M Foley, Matthew R Barone, Patrick E Hopkins and Stephen McDonnell
  • Atomically-thin layered films for device applications based upon 2D TMDC materials ABS S. McDonnell, R.M. Wallace
  • MoS2–titanium contact interface reactions ABS S McDonnell, C Smyth, CL Hinkle, RM Wallace
  • GaSb Oxide Thermal Stability studied by Dynamic-XPS. Journal of Vacuum Science and Technology B, 32, (2014), 041201 ABS S. McDonnell, B. Brennan, K. Winkler, P. Baumann, E. Bursa and R. M. Wallace
  • Hole Contacts on Transition Metal Dichalcogenides: Interface Chemistry and Band Alignments. ACS Nano, 8 (6), (2014) 6265–6272 ABS S. McDonnell, A. Azcatl, R. Addou, C. Gong, C. Battaglia, S. Chuang, K. Cho, A. Javey and R. M. Wallace
  • Defect Dominated Doping and Contact resistance in MoS2. ACS Nano 8 (3), (2014) 2880-2888 ABS S. McDonnell, R. Addou, C. Buie, R. M. Wallace, C. L. Hinkle
  • Controlling the Atomic layer Deposition of Titanium Dioxide on Silicon: Dependence on Substrate Termination. The Journal of Physical Chemistry C 117, (2013) 20250-20259 ABS S. McDonnell, R. C. Longo, O. Seitz, J. B. Ballard, G. Mordi, D. Dick, J. H. G. Owen, J. N. Randall, J. Kim, Y. J. Chabal, K. J. Cho, R. M. Wallace
  • The effect of graphite surface condition on the composition of Al2O3 by atomic layer deposition. Applied Physics Letters 97 (2010) 082901 ABS A. Pirkle, S. McDonnell, B. Lee, J. Kim, L. Columbo, R. M. Wallace

Courses Taught

  • Materials for Electronic, Magnetic and Optical Applications Fall 2023
  • Introduction to Materials Science Spring 2023