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Analysis of Contact Interfaces for Single GaN Nanowire Devices
Published on: November 15, 2013
9.8K
InGaAs-GaAs Nanowire Avalanche Photodiodes Toward Single-Photon Detection in Free-Running Mode
Alan C Farrell1, Xiao Meng2, Dingkun Ren1
1Department of Electrical Engineering , University of California, Los Angeles , Los Angeles , California 90095 , United States.
Nano Letters
|December 6, 2018
Summary
Researchers developed a new nanowire-based avalanche photodiode for near-infrared single-photon detection. This technology significantly reduces afterpulsing and dark count rates, enabling high-performance LiDAR systems.
Area of Science:
- Optoelectronics
- Photonics
- Materials Science
Background:
- Near-infrared (NIR) single-photon detection is crucial for LiDAR, autonomous vehicles, and remote sensing.
- Current silicon-based SPADs are limited to shorter wavelengths, while InGaAs-InP SPADs suffer from high dark count rates (DCR) and afterpulsing.
- Existing technologies face limitations in performance, portability, and pixel density for commercial applications.
Purpose of the Study:
- To introduce a novel separate absorption and multiplication avalanche photodiode (SAM-APDs) platform using vertical InGaAs-GaAs nanowire arrays.
- To overcome the limitations of existing SPADs for high-performance NIR single-photon detection.
- To enable the design of compact and portable LiDAR systems without active quenching circuitry.
Main Methods:
- Fabrication of a photodiode composed of 4400 vertical InGaAs-GaAs nanowires.
- Confining avalanche events within individual nanowires to reduce avalanche volume and trap filling.
- Characterization of dark count rate (DCR), photon count rate, and timing jitter.
Main Results:
- Achieved a DCR below 10 Hz due to a reduced fill factor.
- Demonstrated photon count rates of 7.8 MHz.
- Measured timing jitter of less than 113 ps.
- Exhibited extremely low afterpulsing probability, enabling free-running operation.
Conclusions:
- The proposed nanowire-based SAM-APD platform offers a significant advancement for NIR single-photon detection.
- This approach enables the design of high-performance, portable LiDAR systems by eliminating the need for active quenching circuitry.
- The technology represents a potential stepping stone for next-generation InGaAs SPADs and focal plane arrays.
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