Use of carbon micro-particles for improved infrared temperature measurement of CMOS MEMS devices

作者：Hopper Richard H^*; Haneef Ibraheem; Ali Syed Zeeshan; Udrea Florin; Oxley Christopher H

来源：Measurement Science and Technology, 2010, 21(4): 045107.

DOI：10.1088/0957-0233/21/4/045107

• temperature measurement
• infrared thermal microscopy (IR)
• carbon micro-particle
• micro-electro-mechanical systems (MEMS)
• complementary metal oxide semiconductor (CMOS)
• thermal flow sensor

We report a technique which can be used to improve the accuracy of infrared (IR) surface temperature measurements made on micro-electro-mechanical systems (MEMS). In this work, a silicon-on-insulator (SOI) complementary metal oxide semiconductor (CMOS) MEMS thermal flow sensor was studied. The device consists of a meander-shaped resistive heater element that was fabricated using CMOS aluminum metallization and embedded in an SOI silicon oxide (SiO2) membrane. Conventional IR temperature measurements, made on the active device, were shown to give significant surface temperature errors-a consequence of the optical transparency of the SiO2 membrane and low emissivity of the metalized areas. Radiative carbon micro-particles were used to improve the measurement accuracy. By making IR measurements on carbon micro-particles placed in isothermal contact with parts of the MEMS sensor's structure, the accuracy of the surface temperature determination was significantly improved. The peak device operating temperatures measured using the 'IR micro-particle' technique were found to be in good agreement with those obtained from thermoelectric characterization. The work shows how wide area surface temperature profiles can be quickly built up by imaging multiple micro-particles using an IR charge-coupled device (CCD) detector array. The IR micro-particle technique removes the problems associated with coating MEMS sensors with a uniform high emissivity layer, which may cause damage to such devices and/or affect their thermal performance due to additional heat spreading.

• 出版日期2010-4