4 October 2010


Patent granted for NCSU’s buffer-free GaN-on-Si technology

Jay Narayan, the John C. Fan Distinguished Chair professor of Materials Science and Engineering at North Carolina State University (NCSU), and former NCSU Ph.D. student Thomas Rawdanowicz have just been granted a patent for technology that allows gallium nitride (GaN) sensors and devices to be integrated directly into silicon-based integrated circuits without any buffer layers for the first time, it is claimed (US Patent 20050124161 'Growth and integration of epitaxial gallium nitride films with silicon-based devices', originally filed in 2004). “This enables the development of high-power (high-voltage and high-current) devices that are critical for the development of energy distribution devices, such as smart grid technology and high-frequency military communications,” says Narayan.

“This integration of GaN on the silicon platform without any buffer layers has enabled the creation of multi-functional smart sensors, high-electron-mobility transistors, high-power devices, and high-voltage switches for smart grids which impact our energy and environmental future,” reckons Narayan.

Integrating GaN into silicon chips also makes a broader range of radio frequencies available, which will enable the development of advanced communication technologies. “These devices stand to meet the challenges of high-power, high-frequency and high bandwidth needs for advanced consumer applications and military satellite communications,” Narayan says.

“Direct integration of devices based on different types of semiconductors onto silicon chips is of considerable interest because it can enable different functionalities, such as lasers or higher-performance transistors,” comments Dr Pradeep Fulay of the US National Science Foundation (NSF), which funded the research. “Narayan has used a special process that allows integration of  semiconducting materials like GaN on the silicon so as to create hybrid-type computer chips. This research will likely lead to transistors with far superior power and performance sought for many commercial and military communication applications,” he reckons.

The research was originally published in ‘Epitaxial GaN on Si(111): Process control of SiNx interlayer formation’ Applied Physics Letters 85(1), 133 (2004). The NSF is currently funding additional research by Narayan in this area. A US-based corporation is currently in the process of licensing the technology.

Search: GaN-on-Si GaN sensors



For more: Latest issue of Semiconductor Today