A Novel III-Nitride UV Avalanche Photodetector

Period of Performance: 07/01/1998 - 01/01/1999


Phase 1 SBIR

Recipient Firm

NZ Applied Technologies Corp.
14A Gill Street
Woburn, MA 01801
Principal Investigator


NZ Applied Technologies proposes to develop gallium nitride and aluminum gallium nitride high sensitivity avalanche photodetectors for solar blind ultraviolet wavelength applications. Solar blind ultraviolet avalanche photodetectors and position sensitive arrays with high sensitivity have broad applications in military, space, automotive, engine monitoring, flame detection, and environmental monitoring. The Al(x)Ga(1-x)N direct wide bandgaps covers from 3.4 to 6.2eV corresponding to a wavelength range of 365 to 200nm. These are ideal materials for developing UV photodetectors due to relatively high mobility, sharp cut-off wavelength, and high quantum efficiency. In Phase I, we will demonstrate the feasibility of the GaN/AlGaN APD solar blind photodetectors through the use of modeling and iterative fabrication runs. To overcome the high dislocation density problem found in traditional III-nitride MOCVD growth methods, we will use a novel approach to device structures coupled with the proven MOCVD technique. Using this novel APD structure we can effectively reduce dislocation density and fabricate the homojunctions and heterostructures, which are ultimately required by the APD device. In Phase II, we will refine the device designs, improve device performance, and to bring this high sensitivity ultraviolet detector to the marketplace. There are numerous commercial applications required for high sensitivity ultraviolet solar blind photodetectors such as automotive, engine and environmental monitoring, and flame detection.