QWIP-LED/CCD Coupling Study

Abstract

Many space-based imaging applications demand a sensitive, low noise long wavelength IR detector which is able to image a wide field of view in a short time. Quantum Well Infrared Photodetector (QWIP)-LED detectors offer the potential for large imaging area, and ultra-low noise operation when cooled to cryogenic temperatures (approx. 30K). Due to these factors the QWIP-LED holds a significant advantage over conventional detectors. It is in the area of system efficiency, however, that current QWIP-LEDs are less competitive for low signal space applications. This study was a collaborative effort between EMS technologies, DND, CRESTech and NRC with a goal to design and implement a method to increase the efficiency of QWIP-LED systems. As a result of this study, it has become apparent that early projections about the cost, quality, and efficiency of pixelless QWIP-LED technology were highly optimistic regarding critical implementation details. Unforeseen difficulties with the application of standard' LED and grating technologies to a non-standard device severely impacted the predicted efficiency for both absorption and emission. EMS' research into the IR detector market allowed realistic comparisons to be made for expected applications and showed that, in the near term and at the current rate of development, the QWIP-LED would not be an easily manufacturable competitive alternative due to cryogenic cooling requirements, unexplained material defects, and overall low efficiency. The competing QWIP-multiplexer which is now commercially available would have identical noise and cooling specifications with much higher efficiency at a comparable cost. Uncooled bolometric detectors would compete favourably for high signal terrestrial and earth-observing markets while at the high performance end, more efficient thin film HgCdTe detectors can now cover most wavebands of interest with much higher efficiency, thus out-competing QWIP-LED for space applications.

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Document Details

Document Type
Technical Report
Publication Date
Nov 01, 2000
Accession Number
ADA385572

Entities

People

  • A.l. Scott
  • Shan Chiu

Organizations

  • Defence Research and Development Canada

Tags

Communities of Interest

  • Advanced Electronics
  • Engineered Resilient Systems
  • Ground and Sea Platforms
  • Human Systems
  • Sensors

DTIC Thesaurus Topics

  • Cryopumping
  • Detection
  • Detectors
  • Fabrication
  • Films
  • Infrared Detectors
  • Long Wavelengths
  • Low Noise
  • Manufacturing
  • Materials
  • Optics
  • Quantum Efficiency
  • Quantum Wells
  • Refractive Index
  • Semiconductors
  • Thin Films
  • Two Dimensional

Readers

  • Applied Combinatorial Optimization and Logic Circuit Design.
  • Image Processing and Computer Vision.
  • Thermal Physics or Thermal Science.

Technology Areas

  • Quantum Computing
  • Space