High Brightness Blue LED's

A $1B commercial blue optoelectronics industry supplying full color displays, high speed communications systems, and high density optical recording devices will happen. The question is: which technology, II-VI materials, III-V nitrides, or silicon carbide and its alloys, will dominate? Theoretical calculations and experimental external quantum efficiencies combined favor a direct band gap material; the mechanical properties of the III-Vs are superior to the II-VIs; contact technology is more mature in silicon carbide. We propose a novel high brightness blue LED based on GaN heterostructures grown by chemical vapor deposition on conductive silicon carbide substrates to take advantage of both the nitride and silicon carbide materials systems. The GaN heterostructure will use a resonant optical cavity analogous to those used in ALGaAs LED technology for increased efficiency. Phase I will be devoted to the fabrication of distributed Bragg reflectors (DBRs) using a multilayer stack of GaN/A1N. In Phase II, a complete GaN LED structure will be fabricated and the performance enhancement provided by the resonant cavity structure will be determined. In Phase III, bright blue LEDs will be manufactured and the GaN-based technology will be extended to other optoelectronics including lasers for communications and optical storage. Anticipated Benefits: The availability of high brightness blue LEDs based on the resonant cavity structure could make full color solid state display viable. The additional bonus of a narrow emission linewidth provided by the resonant cavity could allow solid state blue light emitters to be used in WDM fiber optic networks or for high density magneto-otpic data storage devices