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 micro-particles. 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.