Ekerdt, John G. Ph.D.
Dick Rothwell Endowed Chair in Chemical Engineering
Associate Dean for Research in Engineering
|Office:||CPE 4.468||Mailing Address:|
|Phone:||(512) 471-4689||The University of Texas at Austin|
|Fax:||(512) 471-7060||McKetta Department of Chemical Engineering|
||200 E Dean Keeton St. Stop C0400|
|UT Mail:||C0400||Austin, TX 78712-1589|
Research Areas: Advanced Materials, Polymers & Nanotechnology and Energy
Ph.D., Chemical Engineering, University of California Berkeley (1979)
B.S., Chemical Engineering, University of Wisconsin (1974)
Surface and materials chemistry of metal and oxide thin films and hetero-structures – alone and integrated with semiconductors; film nucleation; film growth by atomic layer deposition and film removal by atomic layer etching; area-selective growth phenomena.
|Figure 1. We explore the growth of crystalline perovskite films on Si(001) and Ge(001).
The ABO3 perovskites, such as SrTiO3 (STO)
can be grown directly on Ge(001) in an
all-chemical atomic layer deposition process.
|Figure 2. We study how AS-ALD differs on planar and non-planar surfaces. We demonstrate and quantify ways to confer selectivity to a substrate using surface features. Self-assembled monolayers form defects at regions of high curvature enabling nucleation of TiN films in ALD. This is in contrast to a treated planar surface with no features, which exhibits complete blocking of TiN up to a certain limit of ALD cycles.|
We study the surface and materials chemistry of metal and oxide thin films and hetero-structures – alone and integrated with semiconductors. We seek to understand and describe film nucleation, film growth by atomic layer deposition and film removal by atomic layer etching, and area-selective growth phenomena. The programs are motivated by applications in electronic materials, energy and sensors. The research programs are highly interdisciplinary and involve collaborations with faculty in chemical engineering, physics and electrical engineering, and researchers in industry.
The research on area selective atomic layer deposition (AS-ALD) explores how to passivate the surfaces using organic blocking layers that either self-assemble or are lithographically-patterned, the robustness of the blocking layer and how the blocking layer fails. In parallel we study the chemical nature of the active surface for ALD so thin and uniform films can be deposited in the active regions. AS-ALD projects are exploring metals, simple binary metal oxides, and ternary oxides, and the growth of amorphous and crystalline films. By understanding how film growth can be controlled through selective nucleation, we can enhance the properties of these ultra-thin films and work towards developing a bottom-up approach to nanomanufacturing devices.
The research on crystalline oxide and perovskite films seeks to understand the chemical reactions responsible for atomic layer deposition growth and the interfacial reactions responsible for forcing the films to grow in a crystalline form. Studies with perovskites explore homoepitaxy and heteroepitaxy of perovskite films using molecular beam epitaxy and atomic layer deposition and the role of the growth surface termination and methods to enhance wetting/spreading to realize two dimensional epitaxial growth and control the properties in the perovskite layer. These studies explore the monolithic integration of functional oxides with silicon, germanium, and gallium nitride to allow for integrated heterostructures on the same platform as the integrated circuits. Some of the heterostructures find applications in low power electronics and in energy applications to take advantage of electron and hole transport across heterointerfaces.
Awards & Honors
Fellow of the American Association for the Advancement of Science (2012)
American Society for Engineering Education Chemical Engineering Division Chemstations Award (2012)
Fellow of the American Institute of Chemical Engineers (2006)
Joe J. King Professional Engineering Achievement Award, College of Engineering, University of Texas (2005)
Hamilton Book Awards, for Chemical Reactor Analysis and Design Fundamentals, University Co-op Society (2003)
Charles M. A. Stine Award in Materials Science and Engineering, American Institute of Chemical Engineers (2001)
Dick Rothwell Endowed Chair in Chemical Engineering (2001)
Chemical Engineering Department Teaching Award (1994)
- Selective Growth of Titanium Nitride on HfO2 across Nonolines and Nanopillars, (S. N. Chopra, Z. Zhang, C. Kaihlanen, J. G. Ekerdt) Chemistry of Materials (DOI 10.1021/acs.chemmater.6b01036) 28, 4928-4934 (2016).
- Precursor Dependent Nucleation and Growth of Ruthenium Films during Chemical Vapor Deposition, (Wen Liao and John G. Ekerdt) J. Vacuum Science and Technology A (doi: 1116/1.4953882) 34, 041514 (2016).
- First-principles predictions of ruthenium-phosphorus and ruthenium-boron glassy structures and chemical vapor deposition of thin amorphous ruthenium-boron alloy films, (Daniel E Bost, Hyun-Woo Kim, Chia-Yun Chou, Gyeong S. Hwang, John G. Ekerdt) Thin Solid Films (doi10.1016/j.tsf.2016.12.016) 622, 56-64 (2017).
- Zintl layer formation during perovskite atomic layer deposition on Ge (001), (Shen Hu, Edward L. Lin, Ali K. Hamze, Agham Posadas, HsinWei Wu, David J. Smith, Alexander A. Demkov, and John G. Ekerdt) Journal of Chemical Physics (DOI: 10.1063/1.4972071) 146, 052817 (2017)
- Epitaxial Growth of Barium Titanate Thin Films on Germanium via Atomic Layer Deposition, (E. L. Lin, A. B. Posadas, H.-We. Wu, D. J. Smith, A. A. Demkov, J. G. Ekerdt) Journal of Crystal Growth (doi: 1016/j.jcrysgro.2017.08.003) 476, 6-11 (2017).
- Cubic Crystalline Erbium Oxide Growth on GaN(0001) by Atomic Layer Deposition (P.-Y. Chen, A. B. Posadas, S. Kwon, Q. Wang, M. J. Kim, A. A. Demkov, J. G. Ekerdt) J. Applied Physics 122, 215302 (2017).