Ekerdt, John G. Ph.D.

Dick Rothwell Endowed Chair in Chemical Engineering
Associate Dean for Research in Engineering

Photo of John G. Ekerdt

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
Email: ekerdt@che.utexas.edu 200 E Dean Keeton St. Stop C0400
UT Mail: C0400 Austin, TX 78712-1589

Research Areas: Advanced Materials, Polymers & Nanotechnology and Energy

Research Group Website

Research Presentation for Prospective Graduate Students

Future Directions in Chemical and Bioengineering Report

Educational Qualifications

Ph.D., Chemical Engineering, University of California Berkeley (1979)
B.S., Chemical Engineering, University of Wisconsin (1974)

Focus

Surface, growth and materials chemistry of ultrathin metal, dielectric, ferroelectric, and polymer films. Structure-property relationships of crystalline oxides and amorphous metals in electronics and energy applications.

Graphic showing crystalline STO grown at 250 C, directly on a template layer.

 Illustration to show how one  3-vinyl perylene was used to titrate strained oxygen vacancy defects on silicon dioxide.
Figure 1: We are exploring the growth of crystalline perovskite films on Si(001) and Ge(001).  The ABO3 perovskites, such as SrTiO3 (STO), LaAlO3, BaTiO3, are grown by atomic layer deposition (ALD) on a 1.6 nm thick STO buffer layer that is grown using molecular beam epitaxy on Si(001).  The transmission electron microscopy image above shows crystalline STO grown at 250 C, directly on a buffer layer.  ALD is possible directly on Ge(001). Figure 2: We are studying the chemical nature of the sites where semiconductor and metal particles and films nucleate on oxide surfaces.  We employ fluorescent probes that are designed to react with and bind to different possible sites.  The high sensitivity of this technique allows us to detect defects at concentrations as low as 0.0001 sites nm-2. The image above illustrates how one  3-vinyl perylene was used to titrate strained oxygen vacancy defects on silicon dioxide.

Research

The focus of my research is on the surface, growth and materials chemistry of metal, dielectric, ferroelectric, and polymer thin films.  We seek to understand and describe nucleation and growth of films and nanostructures, their structure-property relationships, and site-specific reactions that lead to their formation.  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.

Metal films find applications in sensors, optics and microelectronics, and as the critical dimensions or size of the applications and systems decrease, the metal film’s thickness will decrease to tens of atomic diameters at most and must have a specific microstructure.  Our program seeks to describe how films form, with an emphasis on nucleation and island coalescence, the evolution of interfacial layers that bind the film to the substrate, how properties of bulk materials scale with thickness, and precisely how short range order is preserved as the film thickness approaches thicknesses that are ten atomic diameters.

The research on crystalline 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 and germanium to allow for integrated heterostructures on the same platform as the integrated circuits.  Some of the heterostructures find applications 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)
Phi Kappa Phi Award for Dedicated Service in the Promotion of Excellence in Higher Education (1997)
Dick Rothwell Endowed Chair in Chemical Engineering (2001)
Chemical Engineering Department Teaching Award (1994)
Z. D. Bonner Professorship in Chemical Engineering (1991-2001)
Quantum Chemical Corporation Endowed Fellow in Engineering (1990-91)
Laurence E. McMakin Centennial Fellow in Chemical Engineering (1983-90)
Best Fundamental Paper, South Texas Section of AIChE (1980)
The University of Texas at Austin Engineering Foundation Faculty Excellence Award (1980, 1983, 1987, 1993)
Outstanding Young Member Award, 1984, South Texas Section of AIChE
Outstanding Engineering Teaching by an Assistant Professor, University of Texas (1985)

Selected Publications

    • Epitaxial strontium titanate films grown by atomic layer deposition on SrTiO3-buffered Si(001) substrates (Martin D. McDaniel, Agham Posadas, Thong Q. Ngo, Ajit Dhamdhere, David J. Smith, Alexander A. Demkov, and John G. Ekerdt) Journal of Vacuum Science and Technology A 31, 01A136- (1-9) (2013).
    • Epitaxial growth of LaAlO3 on SrTiO3-buffered Si(001) substrates by atomic layer deposition (Thong Q. Ngo , Agham Posadas, Martin D. McDaniel, Domingo A. Ferrer, John Bruley, Chris Breslin, Alexander A. Demkov, and John G. Ekerdt) Journal of Crystal Growth 363, 150-157 (2013).
    • Epitaxial c-axis oriented BaTiO3 thin films on SrTiO3-buffered Si(001) by atomic layer deposition (Thong Q. Ngo, Agham B. Posadas, Martin D. McDaniel, Chengqing Hu, John Bruley, Edward T. Yu, Alexander A. Demkov and John G. Ekerdt) Applied Physics Letters 104, 082910 (1-4) (2014).
    • Effect of CO on Ru Nucleation and Ultra-smooth Thin Film Growth by Chemical Vapor Deposition at Low Temperature (Wen Liao, John G. Ekerdt) Chemistry of Materials 25, 1793-1799 (2013).
    • Titration of Free Hydroxyl and Strained Siloxane Sites on Silicon Dioxide with Fluorescent Probes (Joseph M. McCrate, John G. Ekerdt) Langmuir 29, 11868-11875 (2013).
    • Detection of Low-Density Surface Sites on Silica:  Experimental Evidence of Intrinsic Oxygen-Vacancy Defects (Joseph M. McCrate, John G. Ekerdt) Chemistry of Materials (doi: 10.1021/cm500095p) (in press).