Theodosia Gougousi

Theodosia Gougousi
Contact Information

gougousi@umbc.edu 
410-455-6874
Physics, Rm 317

Research Pages

Title

Professor
Graduate Program Director – Physics

Education

Ph.D. Physics – University of Pittsburgh, 1996
M.Sc. Physics – University of Pittsburgh, 1993
B.S. Physics – Aristotle University of Thessaloniki, GREECE, 1990

Previous Experience

Dr. Gougousi joined UMBC after postdoctoral appointments at North Carolina State University and the University of Maryland College Park.

Professional Interests

My research interests lie in the area of nanostructured materials, thin films, and interfaces. As the critical dimension of nanodevices reaches the atomic scale, interface phenomena become critical because they define the operation of nanodevices. As a result, understanding the atomic-level mechanisms that define the formation of heterogeneous interfaces is a critical challenge in advanced materials systems. We investigate the deposition mechanisms and properties of thin films, interfaces, and other low-dimensional materials. We have worked on dielectrics, semiconductors, photonic materials, and 2D materials such as transition metal dichalcogenides. We use both chemical (Atomic Layer Deposition) and physical vapor deposition methods to produce thin films on a variety of substrates and to study their properties.

Atomic layer deposition permits atomic level of the film thickness and morphology and achieves very smooth, uniform, conformal films even on very high aspect ratio structures. Although ALD is usually thought of as a modified version of Chemical Vapor Deposition (CVD), it exhibits some unique features:  film formation is achieved by alternating exposure of a surface to the vapor of two chemical reagents that react in a complementary, self-limiting manner. Complementary means that each of the two reagents must prepare the surface for reaction with the other chemical so the process is cyclical. The dependence of the deposition on favorable surface chemistry can be exploited to achieve selective deposition that is the basis of the so-called “bottom-up” approaches for the formation of nanostructures.

Selected Publications

A complete list of publications can be found here.

Theodosia Gougousi; Low-temperature dopant-assisted crystallization of HfO2 thin films ACS Crystal Growth & Design accepted (2021).

Jaron A. Kropp, Ankit Sharma, Wenjuan Zhu, Can Ataca, and Theodosia Gougousi; Surface Defect Engineering of MoS2 for Atomic Layer Deposition of TiO2 Films ACS Appl. Mater. Interfaces 12, 42, 48150–48160, (2020).

Molly A. May, David Fialkow, Tong Wu, Kyoung‐Duck Park, Haixu Leng, Jaron A. Kropp, Theodosia Gougousi, Philippe Lalanne, Matthew Pelton, Markus B. Raschke NanoCavity QED with Tunable NanoTip Interaction Advanced Quantum Technologies 3(2),  1900087  (2020).

Robinson Kuis*, Theodosia Gougousi*, Isaac Basaldua, Paul Burkins, Jaron A Kropp, Anthony M Johnson; Engineering of Large Third-Order Nonlinearities in Atomic Layer Deposition Grown Nitrogen-Enriched TiO2 ACS Photonics 6 (11), 2966-2973 (2019).

Kyoung-Duck Park, Molly A May, Haixu Leng, Jiarong Wang, Jaron A Kropp, Theodosia Gougousi, Matthew Pelton, Markus B Raschke, Tip-enhanced strong coupling spectroscopy, imaging, and control of a single quantum emitter Science advances 5 (7), eeav5931 (2019).

Jaron A. Kropp, Yuhang Cai, Zihan Yao, Wenjuan Zhu, Theodosia Gougousi, Atomic layer deposition of Al2O3 and TiO2 on MoS2 surfaces, Journal of Vacuum Science & Technology A 36, 06A101 (2018).

Liwang Ye, Jaron A. Kropp, and Theodosia Gougousi, In situ Infrared Spectroscopy Study of the Surface Reactions During the Atomic Layer Deposition of TiO2 on GaAs (100) Surfaces, Applied Surface Science 422, 666-674 (2017).

Theodosia Gougousi; Review: Atomic layer deposition of high-k dielectrics on III–V semiconductor surfaces, Progress in Crystal Growth and Characterization of Materials 62 (4), 1-21 (2016).

Alex J. Henegar, and Theodosia Gougousi; Comparison of the reactivity of alkyl and alkyl amine precursors with native oxide GaAs (100) and InAs (100) surfaces, Applied Surface Science 390, 870-881 (2016).

Alex J. Henegar, Andrew J. Cook, Phillip Dang, and Theodosia Gougousi; Native Oxide Transport and Removal During the Atomic Layer Deposition of TiO2 Films on GaAs(100) Surfaces, ACS Applied Materials & Interfaces  8 (3),  1667–1675 (2016).

Gougousi 1 Gougousi 2
Top: Nitrogen-doped TiO2 films that exhibit very strong nonlinear optical response. The difference in color is due to variations in composition.
Bottom: Optical and AFM images of MoS2 monolayer flakes. The thickness of these flakes is 0.7 nm.