Crystal IS, an Asahi Kasei company, announced the successful production of a 4-inch (100mm) diameter single-crystal aluminum nitride (AlN) substrate. Particularly, this is the first reported aluminum nitride substrate at this size. Also, this development demonstrates the scalability of Crystal IS processes for growing AlN bulk single-crystals to meet production demands for this semiconductor material.

Mainly, aluminum nitride substrates have low defect densities, high UV transparency, and low concentrations of impurities. AlN is attractive for a variety of industries, due to its ultra-wide bandgap and very high thermal conductivity. Among them are UVC LEDs and power devices. Specifically, the 4-inch substrate produced shows a usable area of over 80% based on current requirements for UVC LEDs.

“We are extremely excited to announce the achievement of a 4-inch bulk aluminum nitride substrate,” said Dr. Naohiro Kuze, Executive Fellow at the Research Laboratory of Advanced Science and Technology, Asahi Kasei. “This accomplishment signifies that aluminum nitride is commercially viable for new industries beyond just UVC LEDs.”

Crystal IS was founded in 1997 to develop native aluminum nitride substrates. Mainly, the company manufactures UVC LEDs on its commercial process for 2-inch diameter substrates. Specifically, these LEDs enable industry-leading reliability and performance at the ideal germicidal wavelengths from 260 to 270nm. Also, the current capacity of the facility can meet the volume requirements for consumer devices using UVC LEDs based on the existing 2-inch production line.

“This indicates the scalability of our processes to deliver quality devices on aluminum nitride,” said Eoin Connolly, President and CEO of Crystal IS. “We are proud of the team’s accomplishment and its impact on the semiconductor industry as a whole.”

Currently, Crystal IS produces thousands of 2-inch substrates annually to support the production of its Klaran and Optan product lines. The commercialization of 4-inch AlN substrates will quadruple the device output of the existing footprint of the Green Island facility. Also, it will enable the development of new applications on aluminum nitride substrates. This would result from the integration into existing fabrication lines for power and RF devices using alternative materials.

Moreover, Crystal IS will present the progress on 4-inch substrates at this month’s 23rd American Conference on Crystal Growth and Epitaxy in Tucson, Arizona. More information on aluminum nitride and Crystal IS products are available on cisuvc.com.