A Novel Structure of Thermopile Infrared Detector with High Responsivity Based on CMOS Process

Abstract

Superscript textThermopile-type Infrared detector is more and more popular in many fields, including infrared spectroscopy, radiometry, security systems and many consumer products. This paper reports a novel n-poly/p-poly thermopile suspension structure with four pairs of thermopiles that compatible with Complementary Metal-Oxide Semiconductor (CMOS) technology and its fill factor is larger than 90%. No additional material is needed to enhance infrared absorption since the passivation layer provided by the CMOS process is sufficient for certain infrared spectral bands. With the selected material parameters the optimal structure parameters are obtained after simulation. Through the theoretic calculation, this novel IR detector has good properties of high responsivity (larger than 1000V/W) and detectivity (larger than 1×108cm Hz1/2W-1) and low response time (shorter than 30ms).