Performance of miniaturized LPCVD-SiN-membrane-based 7-14 μm infrared thermal detector: Analytical, modeling, and experimental study

This paper investigates the performance of Low-Pressure-Chemical-Vapor-Deposition (LPCVD)-deposited Sirich Nitride membrane as absorber material for thermal-detector-type, far infrared (IR) sensor. The performance merit investigated is its sensitivity in terms of temperature increase per irradiance power at 7-14 mum wavelength region of IR radiation emitted by human. Another performance merit investigated is the time constant which indicates how fast the temperature of membrane increase as IR stimulus is absorbed. The issue of scaling down is addressed, to know the influence of membranepsilas structural parameters variations, e.g. lateral size and thickness, to its overall radiation to thermal conversion sensitivity and time constant. The final aim is to optimize SiN membrane performance for future high integration far IR sensors.