A spectrally selective visible microbolometer based on planar subwavelength thin films

Area of Science:

• Optoelectronics
• Nanotechnology
• Materials Science

Background:

• Traditional microbolometers often require complex filter structures for spectral selectivity.
• There is a need for compact, cost-effective microbolometer solutions for visible light detection.

Purpose of the Study:

• To experimentally demonstrate a novel, compact, and low-cost visible microbolometer.
• To utilize metal-insulator-metal (MIM) planar subwavelength thin films for resonant absorption-based spectral selectivity.

Main Methods:

• Fabrication of a microbolometer device using MIM planar subwavelength thin films.
• Experimental characterization of the device's spectral response and responsivity in the visible range.
• Comparison with a control device (bare gold bolometer) to quantify performance enhancement.

Main Results:

• The proof-of-principle microbolometer demonstrated spectrally selective properties in the visible frequency range.
• A responsivity of approximately 10 mV/W was achieved at room temperature at 638 nm resonant wavelength.
• The responsivity was about ten times higher than that of the bare gold control device.

Conclusions:

• The proposed MIM microbolometer offers a viable solution for compact and inexpensive visible light detectors.
• Resonant absorption in MIM thin films provides spectral selectivity without additional filters.
• The technology shows promise for large-format fabrication and cost-efficient detector development.