(6bu) Development of Thin Film Deposition & Etching Processes for Challenging Materials

The ability to efficiently scale up production of novel material systems for future applications remains a challenging bottleneck for the adoption of a variety of new technologies. Pressing examples include: a) Topological insulators for low power switching, non-volatile memory, and energy harvesting applications, b) Complex metal oxides for photo- and electro-catalytic applications, c) Chromium free anti-galvanic barrier coatings for durability in extreme environments, among many others. A common theme among many of these materials is that precise control over stoichiometry, microstructure, and crystallinity (frequently in the form of epitaxial thin films) has only been achieved at high temperatures and using deposition techniques not well suited to large areas.

Magnetron Sputter Epitaxy (MSE) presents itself as a viable alternative to pulsed laser deposition and molecular beam epitaxy for its ability to retain precise control over stoichiometry over larger areas. MSE may be further improved with the adoption of pulsed deposition practices such as High Power Impulse Magnetron Sputtering (HiPIMS). HiPIMS offers many advantages in that process developers are capable of controlling and tuning ion fractions and ion energy during deposition. This control over ion energy ensures control over film stress, crystallinity, and many other metric of interests at room temperature.

Using HiPIMS as an enabling technology, I plan to devote a portion of my early career to furthering HiPIMS research as a reactive sputtering technique, in particular for material systems that require epitaxial heterostructures. My belief is that a significant number of these material systems may be deposited epitaxially at room temperature in a manner that will offer flexibility on substrate choice as well as enable rapid commercialization given the prevalence of conventional magnetron sputtering in high volume manufacturing. Concurrently, I envision participating in the development of HiPIMS as a highly energy tailored etching technique. The ability to control the ion energy of reactive species is a crucial component of atomic layer etching (ALE) process development for future of the semiconductor processing industry.

Research Experience

My research experience has spanned from basic science and phenomena discovery in electronic materials to applied research in coordination with both established industrial partners and start-up technology companies for products close to market release for high volume manufacturing. My doctoral work with Dr. Edmund Seebauer in the Department of Chemical and Biomolecular Engineering at the University of Illinois focused on the formation of medium range order in amorphous TiO₂ and the transport of photogenerated charge carriers across TiO₂/perovskite interfaces for heterojunction photocatalysis applications. The work began a deep dive into materials characterization that has followed me beyond graduate school. My postdoctoral research moved me from thermal Chemical Vapor Deposition (CVD) to plasma processes in Dr. David Ruzic’s laboratory. Topics of research there centered around the implementation of secondary plasma sources for improving existing processes including radical sources for reactive sputtering, laser texturing of metal surfaces, and surface wave plasma antennas to assist reactive ion etching processes. Additionally, I gained exposure to a variety of plasma diagnostics including Langmuir probes, radical probes and retarding field energy analyzers.

During Dr. Ruzic’s recent sabbatical, I extended my time at the Center for Plasma-Material Interactions (CPMI) as a Visiting Research Scientist. My duties were expanded to include research advising for eight graduate students and nearly 30 undergraduate students, proposal writing in response to government agency solicitations, as well as initiating new projects with industrial sponsors. In addition to authoring four grants to date at three different agencies, I also independently attracted a sponsored research agreement with DuPont as a principal investigator.

Teaching Interests:

One of the greatest sources of satisfaction for myself when teaching an engineering curriculum comes from introducing students to totally foreign concepts in a way that leaves them stimulated and eager to continue their journey as scholars and future engineers. During graduate school, I served as a teaching assistant (TA) for three semesters covering thermodynamics, kinetics, and senior design/capstone class. Desiring to continue student interactions in such a role, I led discussion sections and taught substitute lectures for my advisor in both thermodynamics as well as an elective class of his development focused on the principles of semiconductor processing. I have discovered that in teaching both core and elective classes, the ability to make the material relatable through connections with industrial processes, current research questions, and personal experiences is invaluable. Such method allows for a certain story telling element that breaks up the potential monotony of a lecture, while offering students perspective and improving their ability to apply concepts outside of their coursework.

In addition to teaching, I look forward to the opportunity to train, advise, and mentor both graduate and undergraduate researchers in my research group much as I have as a research scientist. I plan to continue participating in demonstrations for primary and high school student groups as I have since working as an undergraduate researcher. Given the opportunity as a professor, I would seek to develop and offer plasma engineering and/or semiconductor processing as elective classes.