Freemont, California based company Group4 Labs, has developed an agreement with Alfred University researchers to develop a sacrificial substrate to support the firm's GaN-on-Diamond technology, aiming at improving efficiencies in solid state lighting and advance the sensing and communication industries.
The project will be overseen by two Inamori Professors of materials science in the Kazuo Inamori School of Engineering at AU, S.K. Sundaram and Scott Misture. And they are to develop a substrate material for Group4 Lab’s novel technology which combines diamond and semiconductors to extract heat rapidly, efficiently, passively, and cost-effectively.
Sundaram pointed out that the micron-sized diamond coating is first applied to a sacrificial substrate. When the sacrificial substrate is removed, the diamond coating will then serve as the substrate for further processing of the semiconductor coating.
Misture and Sundaram believe that cordierite glass-ceramics are most suitable as a diamond coating substrate because the two materials are well matched with regard to thermal expansion as well as chemical and thermal stability under the processing conditions of interest to Group4Labs. The "sacrificial" substrate must also be inexpensive because it is disposed of during processing.
According to Misture, in the past, diamonds had been deposited on substrates with different thermal expansion coefficients, which resulted in "mismatch failure and thermal cracking." The main challenge is matching the thermal expansion coefficients of the substrate and the coating. Misture and Sundaram hope to accomplish that by manipulating the glass chemistry and controlling a specific crystal phase from crystallising out.