Small Business Innovation Research/Small Business Tech Transfer
High-Speed Radiation Tolerant Avalanche Photodiodes Based on InGaN for Space Altimeter Systems, Phase I
Project Description
High-performance, radiation-tolerant detectors are required for the time-of-flight laser based rangefinders. Avalanche photodiodes (APDs) are conventionally chosen as detectors for standard laser rangefinder systems. However, the performance of currently used APDs degrades significantly after exposure to high levels of radiation. Integrated Micro Sensors Inc (IMS, Houston, TX)) proposes novel intrinsically radiation-tolerant III nitrides based high-speed APDs superior for use in space-based laser-altimeter systems. The Indium Gallium Nitride (InGaN) alloy has the potential of forming photovoltaic devices covering a range of 0.7 eV (InN) to 3.4 eV (GaN). This energy range allows for providing a perfect match to the 1.06 um wavelength (~1.17 eV) of the lasers used in the time-of-flight range finders. The III-Nitrides exhibit inherent chemical and thermal ruggedness, which makes them suitable for several space and military applications. It has recently been determined that these Nitride materials can offer exceptional radiation tolerance that is well beyond what can be achieved with conventional materials that are currently flown into space. The InGaN APDs to be developed in this project will be targeted for operating conditions up to 250 oC, and up to 2 MeV proton irradiation, which are substantially higher than those for the standard currently used materials, such as Si or GaAs. IMS envisions that devices developed in this project would be especially beneficial to Europa Jupiter System Mission (EJSM) that requires high performance sensors and detectors that can operate with low noise under the severe radiation environment.The ultimate goal of this project is to develop high-speed, radiation-tolerant visible-blind APDs responding to laser beams of 1.06 um wavelength for rangefinder applications.
More »
Anticipated Benefits
The latest improvements in high-performance APDs have enabled impressive applications in aerospace technology. Avalanche photodiodes have gained acceptance in the aerospace industry because of their very high sensitivity in detecting very low light levels, even down to a single photon. Low noise levels and high signal-to-noise ratio properties also provide benefits in aerospace applications. Common applications include laser rangefinders that incorporate APD detectors for more sensitive measurements. Avalanche photodiodes used in these applications can operate with lower light levels and shorter laser pulses, resulting in more eye-safe range finders. High-performance APDs can be tailored to meet these applications and have proven to be valuable tools in aerospace technology. Selecting the proper photodetector and amplifier circuitry to optimize gain for particular applications has played a major role in evaluating overall system performance. Avalanche photodiodes have a built-in gain characteristic that provides a significant advantage in detecting lower light signals. The significance of single-photon detection becomes more apparent when applied to an event, such as measuring atmospheric conditions. To examine cloud formations, for instance, a laser beam is transmitted to the cloud and a return signal provides important distance and spectral information. The reflection contains very low light levels and is severely scattered. The few photons of light that actually reflect back can still be detected by the device to accumulate the data necessary for accurate measurement. Fast receiver modules, confocal microscopy, and particle detection are other common uses for APDs. A silicon APD can detect alpha particles, electrons with energies as high as 150 KeV, and other forms of radiation. Avalanche photodiodes also can be used for light detection and ranging (LIDAR) to measure distance, speed, rotation, and composition of a remote target that can be a clearly defined object, such as a vehicle, or a diffuse object, such as a smoke plume or clouds. Current avalanche photodiodes for communications applications are of much higher cost components than conventional p-i-n photodiodes. The results of the devices developed in this project will enhance the state-of the- art in reliable low-cost avalanche photodiodes for fiber optic communications
More »
Primary U.S. Work Locations and Key Partners
| Organizations Performing Work | Role | Type | Location |
|---|---|---|---|
| Integrated Micro Sensors, Inc. | Lead Organization | Industry | Houston, Texas |
| Jet Propulsion Laboratory (JPL) | Supporting Organization | FFRDC/UARC | Pasadena, California |
Primary U.S. Work Locations
-
California
-
Texas
Suggest an Edit
Recommend changes and additions to this project record.
This is a historic project that was completed before the creation of TechPort on October 1, 2012. Available data has been included. This record may contain less data than currently active projects.