Feasibility of a flip-chip approach to integrate an IR filter and an IR detector in a future gas detection cell

Abstract

In this work we have studied the feasibility of integrating an infrared filter and an infrared detector by means of a flip-chip technique. This filter and detector combination should be the heart of a future gas detection cell based on infrared absorption. In our case the filter is a surface micromachined Fabry-Perot interferometer, and the infrared detector is a bulk micromachined thermopile. The flip-chip technique is an elegant solution to assure the optical micro-alignment of both devices and allows the electrical contact needed to actuate active optical filters.

Design and analysis of the film assembly of thermo-optic infrared focal plane arrays

“…1a, the infrared absorption layer is integrated into multilayer of TOFPA in order to obtain large infrared absorption. The DBRs, fabricated by depositing pairs of alternant high/low index films (amorphous silicon and silicon nitride, a-Si/SiN x ) (Fonseca et al 2004), are functioned as reflectors for the cavity (a-Si film). It is known that the detection sensitivity of FPA based on bimaterial effect can be improved by optimizing structure design for high thermomechanical sensitivity.…”