A Novel Infrared Sensor Structure Compatible to Standard CMOS Process

This paper presents a new type of un-cooled thermal infrared sensor, which is compatible to standard CMOS process. The proposed infrared sensor adopts a suspended n-well containing several p+/n-well diodes as infrared sensing element. The thermal analysis indicates that the sensor exhibits excellent steady-state and transient thermal property. The theoretical analysis shows that the temperature coefficient is independent of temperature and process parameters, which is not true for conventional infrared sensors using single p-n diode. The simulation results based on SMIC 0.18μm CMOS process are consistent with theoretical ones. Compared to traditional p-n diode infrared sensor, the proposed structure is more suitable for constructing an infrared focal plane array (IRFPA) for imaging applications.