This Small Business Innovation Research (SBIR) Phase II project is to demonstrate a novel technique for producing large-diameter freestanding GaN wafers and substrates. Despite the research efforts in the last decade, affordable GaN wafers and substrates of large diameters have not been widely available commercially, which hinders commercialization of high performance GaN-based devices. This Phase II project will demonstrate a unique approach to growth of GaN thick films and fabrication of freestanding GaN wafers and substrates with low densities of dislocations and low wafer bow/warp in an efficient manner. This Phase II research includes crystal growth of GaN thick films, fabrication of GaN wafers and substrates, and extensive characterization of GaN wafers. If this Phase II project is successful, high-quality freestanding GaN substrates of large diameters will become widely available commercially at an affordable price, which will enable volume production and commercialization of high-performance GaN-based light emitters and ultraviolet light detectors.
The broader impact/commercial potential of this project is in the areas of GaN-based light emitting diodes (LEDs), lasers, and ultraviolet (UV) light detectors. GaN-based blue and green high brightness LEDs hold a great promise for solid-state lighting applications because of their tremendous energy savings potential, long lifetime, compactness, and high energy efficiency. Solid-sate lighting will dramatically improve the nation?s energy sustainability in the near future. In addition, freestanding GaN substrates are also needed for fabrication of variety of other high-performance semiconductor devices, such as blue laser diodes for data storage/displays, UV LEDs for water/air purification, high-power RF devices for wireless communication, high-power switching devices for harnessing renewable energies (e.g. wind, solar), and UV detectors for detection/analysis of chemical and biological agents for homeland security applications. Finally, this project will help create jobs in business sectors of energy conservation and renewable energies, and will increase competitiveness of US companies in these business sectors.
In this NSF Phase II SBIR project, a novel crystal growth process and an equipment for producing GaN single crystal thick films were demonstrated, and freestanding GaN single crystal wafers up to 2 inches in diameter were produced. This project also provided training opportunities for several undergraduate students to engage in research activities in the materials science & engineering area at Fairfield Crystal Technology and at a University. The project results also helped Fairfield Crystal attract more funding to further improve the growth process and to commercialize the novel GaN crystal growth technique. In September 2013, Fairfield Crystal Technology was awarded a 3-year ARPA-E research contact totaled $1,425,000 for further development of the GaN crystal growth technology under the ARPA-E SWITCHES project. In the ARPA-E project, Fairfield Crystal aims to demonstrate a crystal gorwth process for producing GaN single crystal boules and wafers of large diameter at a high growth rate. By achieving these goals, Fairfield Crystal will become a prominent supplier of high-quality GaN bulk single crystal substrates to III-nitride semiconductor device manaufacturers worldwide for volume production of variety of high-performance devices. These III-nitride devices, ranging from high-brightness LEDs, blue lasers, high-power devices, high-frequency devices, and photodetectors, will have a great impact on energy conservation through significantly increasing energy efficiencies in lighting and national power grid management, and bringing on new capabilities in regulating and managing power in electrical vehicles, and better harnessing the green power (i.e. solar and wind in particular). As a result, we in the United States will be able to greatly reduce greenhouse gas emission and contribute significantly to a cleaner and more sustainable environment.
