High temperature characterization of a CMOS based infra-red source using thermal-incandescence microscopy

Abstract

This paper presents the high temperature thermal characterization of a Micro-Electro-Mechanical Systems (MEMS) infra-red (IR) thermal source, using non-contact optical approaches, based on IR and thermo-incandescence microscopy. The IR thermal source was fabricated using a CMOS based processing technology and consists of a miniature micro-heater, fabricated using tungsten metallization. The performance and reliability of the IR source is highly dependent on its operating temperature. For short-wave (1.4 µm -2.5 µm) infra-red emission, the operating temperature is in excess of 800°C. Work will be presented in this paper in which spot temperature measurements (> 700 °C) were made on the IR source using thermal-incandescence microscopy. Thermal-optical calibration was achieved by utilizing the known melting point (MP) of different metal microparticles. Optical measurements were compared to those obtained using an electrical approach. The thermal measurements suggest good temperature uniformity across the micro-heater of the IR source.