Two Dimensional Array of Antenna-Coupled Microbolometers

Abstract

Antenna-coupled microbolometers are known for having short time constants and high responsivity, but their small dimensions make them unsuitable for imaging applications where a typical pixel area is generally greater than 20 × 20 μm2. In this paper a two dimensional array of antenna-coupled microbolometers is demonstrated as an area receiver. Using the response of microbolometers to visible frequencies a two-dimensional diagnostic scan in the visible was performed on these arrays which allowed measurement of their homogeneity. Frequency response measurements gave time constants around 130 nsec, similar to the ones obtained for single element microbolometers which indicates that a detector of virtually any size can be fabricated without sacrificing time response. Response and noise measurements show lower noise and higher responsivity compared to single element microbolometers. These results make two-dimensional arrays of antenna-coupled microbolometers a promising option for development of pixels in infrared focal plane arrays.