The Ohio State University recently installed a one-of-a-kind materials system, enabling state-of-the-art growth capabilities in the ultra-wide bandgap range.
The new gallium oxide-capable metal-organic chemical vapor deposition (MOCVD) system is designed and developed by Agnitron Technology, a Minnesota-based supplier of custom MOCVD equipment and R&D services.
The system will allow Ohio State researchers to develop oxide semiconductor materials, namely gallium oxide (Ga2O3), integral to promising ultra-wide bandgap semiconductors for UV-optoelectronic and power electronic device applications. The system will enable the growth of (Al, Ga, In)2O3, which will provide a materials platform for researchers to investigate the fundamental physical properties of this emerging material and maximize the benefits provided by the system — critical to advanced device designs and its broad application in society.
The gallium oxide-capable MOCVD is a radio frequency-heated quartz tube system specially designed for gallium(II) oxide and aluminum gallium oxide epitaxy. The new system design, capable of depositing on 50mm substrates at temperatures as high as 1050°C, has recently been used by Agnitron researchers to produce world-record mobilities in β-Ga2O3.
This installation marks the third MOCVD system housed at Nanotech West Laboratory on West Campus, complementing the existing MOCVD systems dedicated to III-V, III-nitride and II-IV nitride materials.
“This gives us a unique capability here, at Ohio State, in epitaxy, which complements very well our other capabilities in defect spectroscopy, fabrication, and device development and device design,” said John Carlin, Director of the Nanotech West Lab. “It really puts us in a great position to give a real benefit to the OSU materials community.”
The system is a key component of a five-year Multidisciplinary University Research Initiative (MURI) award sponsored by Air Force Office of Scientific Research. The project, “Gallium Oxide Materials Science and Engineering – GAME,” will study the promising wide bandgap semiconductor material’s structure-property relationships and advance the material to new-generation electronic and photonic device applications.
Four co-investigators at Ohio State will share approximately $3.7 million of the total awarded amount ($7.5 million) for the MURI project, led by James Speck at the University of California, Santa Barbara. Ohio State researchers include Jinwoo Hwang, assistant professor in Materials Science and Engineering (MSE); Siddharth Rajan, professor in MSE and Electrical and Computer Engineering (ECE); Steven Ringel, Neal A. Smith Endowed Chair Professor of Electrical Engineering and IMR executive director; and ECE and MSE associate professor Hongping Zhao.
Zhao, who was recruited through the IMR-led Materials and Manufacturing for Sustainability Discovery Theme, will lead the research on the MOCVD growth of gallium oxide and its related alloys and heterostructures, critical for device application.
“It has attracted tremendous attention across the research community because of its availability of native Ga2O3 substrates, and fundamental materials properties promising for electronic and deep-UV optoelectronic applications. However, understanding of this materials system is still at a very early stage, so this MURI project sets a foundation for us, as researchers, to investigate the materials system from materials synthesis, properties all the way to device applications.”
Zhao joined Ohio State in August 2017. Her current research group includes one postdoc, four doctoral students and several master’s and undergraduate students.
“We are very excited to start with this research and look forward to contributing our work to the community,” she said.
Article by Mike Huson, IMR Public Relations Coordinator