Crystal IS, an Asahi Kasei company, has successfully produced a four-inch (100 mm) diameter single-crystal aluminum nitride (AlN) substrate. This is the first reported aluminum nitride substrate at this size and demonstrates the scalability of Crystal IS processes for growing AlN bulk single-crystals to meet production demands for this semiconductor material.
Aluminum nitride substrates have low defect densities, high UV transparency, and low concentrations of impurities. AlN is attractive for a variety of industries, such as UVC LEDs and power devices, due to its ultra-wide bandgap and very high thermal conductivity. 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 four-inch bulk aluminum nitride substrate,” said Dr Naohiro Kuze, Executive Fellow, Research Laboratory of Advanced Science and Technology of Asahi Kasei. Kuze added, “This accomplishment signifies that aluminum nitride is commercially viable for new industries beyond just UVC LEDs”.
Crystal IS manufactures UVC LEDs on its commercial process for two-inch diameter substrates. These LEDs enable industry-leading reliability and performance at the ideal germicidal wavelengths from 260 nm – 270 nm. 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. Connolly added, “We are proud of the team’s accomplishment and its impact on the semiconductor industry as a whole”.
The press release stated that Crystal IS currently produces thousands of 2two-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. It will also enable the development of new applications on aluminum nitride substrates as it integrates into existing fabrication lines for power and RF devices using alternative materials.
