Lateral Heterogeneous Integration of Ultrawide Bandgap AlGaN and Diamond
Abstract
Innovative materials research is proposed for achieving the lateral integration of ultra-wide bandgap (UWBG) materials diamond and AlGaN. The AlGaN will be grown with high Al content to achieve near bandgap matching with diamond. Experimental research will focus on patterned and area selective materials growth including doped materials to produce both n-p-n and p-n-p test structures. The research is based on exciting preliminary results demonstrating significant improvements in both the group-III-Nitride and diamond materials. Based on superior material properties, such as thermal conductivity, carrier mobility, and breakdown field, UWBG materials are promising for revolutionizing key Department of Defense and civilian technologies. Areas of immediate and future DOD need include high-power and RF devices, deep-UV photonics, quantum information and extreme-environment applications including robust high-temperature operation. To make advances toward developing these technologies, while capitalizing on the advantages of UWBG materials, extensive materials research is needed to achieve high-quality heteroepitaxy, effective p- and n-type doping, and heat conduction for thermal management. Systematic studies will focus on growth of diamond using hot-filament chemical vapor deposition (CVD) and AlGaN using metalorganic CVD. To achieve integration, and understanding of the resulting properties, five primary tasks are identified: o Improved materials through the use of interlayers for AlN/AlGaN growth. Interlayers will be developed on a series of substrates beginning with silicon. The impact of the interlayers on doping properties will be investigated. o Achieving ultrahigh seeding density for diamond deposition. Seeding will be based on application of layers that promote dense nano-diamond seeding. Special attention will be devoted to the effect on doping diamond with superior properties and demonstrating area selective diamond growth. o Lateral integration will be investigated for both undoped materials and for n-type AlGaN and p-type diamond for producing p-n-p and n-p-n structures. o Technical focus four will focus on fundamental roles of AlGaN/diamond heterointerfaces on engineering band alignment and the resulting diode characteristics for future implementation into transistors. Various diamond terminations are of interest for their very different impacts on electrical properties. Lateral AlGaN-diamond structures will be studied tailoring the heterointerface. o A series of substrates will be investigated to examine their impact on material improvement. Each phase of the materials growth studies will be backed by extensive characterization including x-ray diffraction, electron microscopy, micro-Raman spectroscopy, and electrical characterization focusing on band offsets. All facilities needed for the successful execution of this research are in place and the investigators possess the expertise to carry out the project. Texas State University is a Hispanic serving institution with 51% racial minorities and 40% Hispanic enrollment, along with large enrollment of veterans and first-generation students, and ranks in the top 20 nationally for the number of bachelorÕs degrees awarded to Hispanic students. Dr. Edwin Piner has extensive industrial and academic expertise in heteroepitaxy and materials research, device processing, and testing. Dr. Mark Holtz has extensive expertise in optical characterization and nanoscale heat transport. Both investigators have demonstrated track records educating students for careers in the high-tech sector including underrepresented talent.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Jul 28, 2023
- Source ID
- W911NF2310267
Entities
People
- Edwin Piner
Organizations
- Army Contracting Command
- Office of the Secretary of Defense
- Texas State University