High performance Ge0.89Sn0.11 photodiodes for low-cost shortwave infrared imaging
Abstract
Low-cost shortwave infrared detectors have great potential for emerging civilian night-vision applications. This paper reports the characteristics of Ge0.89Sn0.11 photodiodes monolithically grown on a Si substrate that holds great promise for those applications. At room temperature, the 500 μm diameter active area device demonstrated a longwave cutoff of 2.65 μm and a responsivity of 0.32 A/W at 2 μm, which corresponds to an external quantum efficiency of 20% without any contribution from the Ge buffer layer. The measured peak specific detectivity at 300 K and 77 K is 1.7 × 109 Jones and 4.3 × 109 Jones, respectively. The specific detectivity at 77 K is only one-order-of-magnitude lower than that of the market dominating extended-InGaAs photodiode. The detailed device analysis indicated that the 700-nm thick fully relaxed high-quality GeSn absorbing layer and the modified depletion region lead to the above-mentioned device performance.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Jul 02, 2018
- Source ID
- 10.1063/1.5020510
Entities
People
- Baohua Li
- Greg Sun
- Huong Q Tran
- Joe Margetis
- John Tolle
- Joshua M. Grant
- Mansour Mortazavi
- Perry C. Grant
- Richard Soref
- Shui-Qing Yu
- Thach Pham
- Wei Du
- Yang Zhang
Organizations
- Air Force Office of Scientific Research
- National Aeronautics and Space Administration
- National Science Foundation
- University of Arkansas
- University of Arkansas at Pine Bluff
- University of Massachusetts
- Wilkes University