Development of infrared detector with slot antenna-coupled microbolometer

Abstract

The current state-of-the-art infrared detection technology requires either exotic materials or cryogenic conditions to perform its duty. Implementing infrared detection by coupling infrared tuned antenna with a micro-bolometer offers a promising technological platform for mass production of un-cooled infrared detectors and imaging arrays. The design, fabrication, and characterization of a planar slotted antenna have been demonstrated on a thin silicon dioxide (SiO2) membrane for infrared detection. The planar slotted antenna was chosen due to its ease of fabrication and greater fabrication tolerance, higher gain and greater bandwidth coveted for the infrared applications. The employment of the SiO2 membrane technology mitigates the losses due to surface waves generated as the radiation coupling into the substrates. In addition, by retaining the membrane thickness to be less than a wavelength, the amount of interference is greatly reduced. A strategically designed planar slotted dipole antenna is implemented along with an integrated direct current (DC) block enabled by co-fabricated on-chip capacitors between the two DC patches to separate DC and high frequency signals without the need for sub-micron DC separation line. As a result of this revision, standard UV photolithography instead of e-beam lithography can be used to fabricate the infrared detectors for mass production. This research is considered as an important step toward our main goal, which is developing ultrafast infrared detector by coupling a planar slotted antenna with a metal insulator metal (MIM) tunneling diode.