Scaling infrared detectors-status and outlook

Area of Science:

• Optoelectronics and Photonics
• Materials Science
• Infrared Detector Technology

Background:

• The 'Law 19' benchmark for HgCdTe photodiode performance signifies a milestone in infrared (IR) detector development.
• It fulfills the long-standing goal of achieving room-temperature operation for photon detectors with background-limited performance.
• This progress paves the way for high-pixel-density, room-temperature IR arrays compatible with diffraction-limited optics.

Purpose of the Study:

• To describe the physical limitations of pixel size in relation to optical aperture and wavelength dependence.
• To evaluate various material systems for IR detectors, comparing them against bulk HgCdTe alloys.
• To address key challenges in achieving ultimate pixel dimensions for focal plane arrays.

Main Methods:

• Analysis of physical limitations imposed by optical aperture on pixel size.
• Comparative evaluation of material systems including colloidal quantum dots and III-V materials against HgCdTe.
• Review of challenges in focal plane array design, such as dark current and hybridization.

Main Results:

• Smaller pixels enhance spatial and temperature resolutions, crucial for megapixel imaging systems.
• Enhanced coupling of radiation to the detector is critical for small pixel quantum efficiency.
• Bolometer arrays are highlighted for their significant commercial market share among thermal detectors.

Conclusions:

• The 'Law 19' benchmark facilitates the development of advanced room-temperature IR detector arrays.
• Future IR imaging systems will benefit from improved resolution and reduced size, weight, and power consumption.
• Overcoming challenges in dark current, hybridization, and readout is essential for next-generation IR focal plane arrays.