Uncooled ultra-thin silicon-on-aerogel nano-bolometers for high-speed thermal imaging
Abstract
Unlike photon detectors whose spectral response is fundamentally limited by the bandgap of semiconductors, bolometers are thermal detectors that measure the power of incident electromagnetic radiation via the optical heating of a thermally sensitive material. They are hence uniquely capable of sensing incident radiation for any electromagnetic frequency at room temperature. However, in conventional microbolometers for room-temperature thermal imaging, undesirable trade-offs among the responsivity, the response speed, and the pixel pitch size have significantly limited their performance such as sensitivity and imaging bandwidth, and hindered further advancement.This project aims to introduce and experimentally demonstrate a new uncooled mid-IR detector concept termed the ultra-thinsilicon-on-aerogel nano-bolometer. This device synergistically combines the ultra-strong bolometric effect at the impact ionizationthreshold of ultra-thin silicon PIN junctions with the exceptionally low heat capacity of ultra-thin silicon and plasmonic mid- IR absorbers. As a result, it enables significantly enhanced temperature resolution and imaging bandwidth compared to conventional microbolometers. Specifically, the device features a pixel dimension of 10×10 #m2, a Noise Equivalent Temperature Difference (NETD) below 20 mK in the LWIR (8-12 #m) imaging band, and a response speed exceeding 100 kHz. Building upon the success of the device demonstration, this project also aims to outline a practical roadmap for developing a large-scale ultra-thin silicon nano bolometer array, offering high-speed and high temperature resolution for room-temperature thermal imaging.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- May 15, 2024
- Source ID
- N000142412308
Entities
People
- Qiushi Guo
Organizations
- Office of Naval Research
- Research Foundation of The City University of New York
- United States Navy