SBIR-STTR Award

Unfortunately, existing AlGaN based ultraviolet laser diodes with wavelengths much shorter than 340 nm suffer from poor performance. This is partially due to the fact that most of the existing research has focused on growth of InGaN lasers on GaN based templates, but a large part is also due to material and processing issues unique to deep UV lasers. New approaches to achieving III-Nitride 280 nm lasers are needed to meets the Navys ambitious goals laid out in this program; it is unlikely that traditional approaches to III-Nitrides will be able to achieve the desired laser performance. Instead it is necessary to develop revolutionarily novel approaches to the growth and fabrication of AlInGaN based UV lasers. To this end, we propose a novel hybrid n-ZnO/AlGaN/p-Si 280 nm UV laser. The objective of this Phase I proposal is to investigate novel techniques required to achieve such a hybrid laser. This objective will be complemented by scientific studies to better understand the physical origins existing performance limitations.

Benefit:
By the end of Phase II it is expected to demonstrate and deliver the first high power 280 nm UV Lasers. Achieving such devices will require major breakthroughs in the existing technology. The Phase I and Phase I Option program proposed herein will seek to develop novel technology that has a strong potential to allow the realization of such devices. By the end of the Phase I Option initial device demonstrations will have been made to layout a groundwork for realizing high power 280 nm laser. The availability of 280 nm will directly support the Navy applications such as to counter hostile fire identification (HFI), Light Detection and Ranging (LIDAR), and three-dimensional (3D) imaging through smoke, dust and smog. 280 nm UV lasers can also be used for applications such as non-line of sight communication, portable bio-agent detection, and next generation optical data storage. The technologies developed may also have crossover potential for other devices based on the III-Nitride material system, including high power microwave electronics, THz detectors and detector arrays, UV LEDs, as well as visible and ultraviolet photodetectors.

Keywords:
280 nm, 280 nm, LEDs, Lasers, AlGaN, ultraviolet, III-nitride

Existing ultraviolet laser diodes with wavelengths much shorter than 365 nm suffer from poor performance. This is partially due to limited research in this area, but a large part is also due to material and processing issues unique to deep UV lasers. New approaches to achieving 340 nm III-Nitride lasers are needed to meet the Navys ambitious goals; traditional approaches to III-Nitrides are unlikely to be able to achieve the desired laser performance. Instead it is necessary to develop revolutionarily novel approaches to the growth and fabrication of AlInGaN based UV lasers. Phase I of this effort involved studying the growth, processing, testing, and demonstration of high power UV LEDs, and the initial demonstration of laser fabrication. This work has laid the ground work for a Phase II effort in which we will pursue novel approached to realizing UV lasers. One of the cornerstones of our novel approach is to use lateral epitaxial overgrowth (LEO) to reduce dislocation density and cracking formation, so as to improve the quality of the active layers. The objective of Phase II will be to demonstrate high average power UV lasers based on these novel designs.

Benefit:
By the end of Phase II it is expected to demonstrate and deliver the first high power 340 nm UV Lasers. Achieving such devices will require major breakthroughs in the existing technology. The Phase II program proposed herein will seek to develop novel technology that has a strong potential to allow the realization of such devices. By the end of the Phase II initial device demonstrations will have been made to layout a groundwork for realizing high power 340 nm laser. The availability of 340 nm laser diode will directly support the Navy applications such as to counter hostile fire identification (HFI), Light Detection and Ranging (LIDAR), and three-dimensional (3D) imaging through smoke, dust and smog. 340 nm UV lasers can also be used for applications such as non-line of sight communication, portable bio-agent detection, and next generation optical data storage. The technologies developed may also have crossover potential for other devices based on the III-Nitride material system, including high power microwave electronics, THz detectors and detector arrays, UV LEDs, as well as visible and ultraviolet photodetectors.

Keywords:
III-nitride, lateral epitaxial overgrowth, ultraviolet, Lasers, AlGaN, LEDs, 340 nm