Development of an infrared thermopile detector with a thin self-supporting SU-8 membrane

• In this paper we present the development and characterization of thermopile detector on a 4 mum thin self-supporting membrane made of the epoxy based photoresist SU-8. The membrane is realized using silicon bulk micromachining techniques. In many existing thermopile detectors, a temperature difference over the thermocouple junctions is achieved by connecting a thin membrane of either Si or Si3N4 to a silicon bulk. These materials suffer from relatively high thermal conductivity, which lowers the sensitivity of the detector. A material such as SU-8 has much lower thermal conductivity and is applied using standard photolithographic processing steps. Simulation results are presented which verifies SU-8 as a better choice than Si and Si3N4 when used as thermal insulating membrane in a thermopile detector. A thermopile consisting of 196 series coupled Ti/Ni thermocouples has been fabricated. Results from measurements are presented, showing a sensitivity of 5.6 V/W and a noise equivalent power (NEP) of 9.9 nW/radicHz.

Ämnesord

TEKNIK OCH TEKNOLOGIER  -- Elektroteknik och elektronik (hsv//swe)

ENGINEERING AND TECHNOLOGY  -- Electrical Engineering, Electronic Engineering, Information Engineering (hsv//eng)

Nyckelord

Thermopile

SU-8

IR

Electrical engineering, electronics and photonics

Elektroteknik, elektronik och fotonik

Publikations- och innehållstyp

ref (ämneskategori)

kon (ämneskategori)