High-Quality, Low-Cost GaN Epitaxy and Characterization

"CBL Technologies and Stanford University propose a VPE growth process and novel GaN epilayer design for electronic/optoelectronic applications. In our low-cost, high-efficiency growth technique, thick GaN and related compounds can be deposited on avariety of substrates. Sequentially, but with altered growth parameters, the process also allows for device quality layers. Typically in other materials systems extremely thick buffer layers provide limited benefits; however, here thick buffer layers ofvarious structures may provide significant electrical contact layers, thermal heat sinking, structural layers for lift-off processes, and improved crystal quality. We believe such a system has a wide range of applications from low-cost light-emittingdiodes to solar-blind detectors and high temperature, radiation hard devices.To this end CBL Technologies and Stanford University propose to provide crystal growth, materials characterization and device fabrication of GaN related structures. In Phase I, CBL Technologies will produce GaN epilayers of various thicknesses and theirquality will be assessed through materials characterization by Stanford University. This will provide an analysis of the range of device possibilities, and the effects of various growth conditions, as well as provide feedback for improvements. Phase IIwill consist of a full implementation of the system for novel device fabrication. It is expected that the characterization, assessment and improvement to the VPE-related growth processes made during the proposed work will translate to improved GaN-based devices. For example, low-cost structures could be fabricated and have a majorimpact in areas such as light-emitting diodes (LEDs) for white lighting applications. Other devices where performance is the driver may also benefit. For example, solar blind detectors, radiation hard devices, and lasers could be manufactured withimproved performance. Because of the great military and commercial interest in systems utilizing GaN-based devices, we anticipate significant benefit