Micromachines (Jun 2022)

High Responsivity Thermopile Sensors Featuring a Mosaic Structure

  • Elisabetta Moisello,
  • Maria Eloisa Castagna,
  • Antonella La Malfa,
  • Giuseppe Bruno,
  • Piero Malcovati,
  • Edoardo Bonizzoni

DOI
https://doi.org/10.3390/mi13060934
Journal volume & issue
Vol. 13, no. 6
p. 934

Abstract

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This paper presents a detailed analysis of a micromachined thermopile detector featuring high responsivity and a versatile mosaic structure, based on 128 60 µm × 60 µm pixels connected in series and/or in parallel. The mosaic structure is based on the one employed for the thermal sensor known as TMOS, which consists of a CMOS-SOI transistor embedded in a suspended and thermally isolated absorbing membrane, released through microelectro mechanical system (MEMS) post-processing. Two versions of the thermopile detector, featuring different series/parallel connections, are presented and were experimentally characterized. The most performant of the two achieved 2.7 × 104 V/W responsivity. The thermopile sensors’ performances are compared to that of the TMOS sensor, adopting different configurations, and their application as proximity detectors was verified through measurements.

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