Infrared thermopile sensor

An infrared thermopile sensor, comprising:

• an infrared sensing chip, comprising:
• a first substrate, comprising a wire-bonding pad and two membrane structures configured by a front-side wet etching;
• a first thermopile sensing element, disposed on one of the membrane structures and generating an object corresponding temperature signal;
• a second thermopile sensing element, disposed on another one of the membrane structures and adjacent to the first thermopile sensing element, and generating a compensation temperature signal;
• and
• a front-end signal processing unit, disposed on the first substrate and electrically connected with the first thermopile sensing element and the second thermopile sensing element, the front-end signal processing unit comprising:
• an ambient temperature sensing element, generating a calibrated ambient temperature information;
• a non-volatile memory, adapted to store the calibrated ambient temperature information of the ambient temperature sensing element;
• and
• an amplifier and an analog-to-digital converter, receiving the object corresponding temperature signal and the compensation temperature signal, and amplifying and converting the object corresponding temperature signal and the compensation temperature signal to a digital signal;
• a silicon cover, bonded to the infrared sensing chip by a wafer-level bonding, and comprising an infrared Fresnel lens focusing a thermal radiation of the object to the first thermopile sensing element, a size of the silicon cover being smaller than a size of the infrared sensing chip, and the wire-bonding pad exposed from the silicon cover;
• a microcontroller chip, connected with the infrared sensing chip, and receiving the digital signal generated by the front-end signal processing unit, and calculating an object temperature according to the calibrated ambient temperature information, the microcontroller chip comprising:
• a second substrate;
• and
• a first metal layer, disposed on an upper surface of the second substrate and comprising a metal material with a low emissivity to reduce thermal disturbance from the microcontroller chip to the infrared sensing chip;
• and
• a plurality of through silicon vias (TSVs), disposed in the second substrate;
• a package substrate, carrying the microcontroller chip, and receiving an output signal or an input signal of the microcontroller chip through the TSVs, and comprising a plurality of contacts disposed on a lower surface thereof, and the TSVs electrically connected to the contacts;
• and
• a sealing encapsulation, covering the package substrate, the microcontroller chip, the infrared sensing chip, and the silicon cover, and an upper surface of the silicon cover being exposed from the sealing encapsulation.