Dark Current Reduction of IR Detectors
Abstract
This research and development program aims at demonstrating a novel approach to dark current reduction for dense infrared detector arrays. This technique is based on the diffusion control junction (DCJ) concept that has been developed at Boston University. The DCJ concept is material and wavelength agnostic and was applied to the design of dense arrays fabricated with InGaAs and HgCdTe. Modeling and simulation was performed to try to better understand the underlying physics. Through this modeling effort, it was demonstrated that a more symmetric annular control junction provides the highest degree of dark current suppression, but at a greater loss of quantum efficiency. Unfortunately, characterization of the actual arrays did not demonstrate a noticeable degree of dark current suppression when biasing neighboring junctions. The results also indicate problems with the device fabrication process. The isolated diodes, arrays, and variable area diodes all have extremely high dark currents, exhibited increased dark current with the contact anneal, and do not vary with junction area. All of these symptoms are inconsistent with what can be expected for p-n junctions formed in SWIR InGaAs using the double layer planar heterostructure. More work is required to determine the cause of these problems.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 19, 2017
- Accession Number
- AD1046277
Entities
People
- Andreau L. Glasmann
- Taylor Hubbard
Organizations
- Boston University