Patent ID: 6793389
Filing Date: 2004-09-21
Classification: G01J

Abstract:
An infrared sensor comprising:a frame formed of a semiconductor material that is not heavily doped; a diaphragm having a perimeter supported by the frame, the diaphragm having a first surface for receiving thermal radiation and an oppositely-disposed second surface, the diaphragm comprising multiple layers including a first dielectric layer, a sensing layer that contains at least a pair of interlaced thermopiles, a second dielectric layer, and a first metal layer defining metal conductors that electrically contact the thermopiles through openings in the second dielectric layer, each thermopile comprising a sequence of thermocouples, each thermocouple comprising dissimilar electrically-resistive materials that define hot junctions located on the diaphragm and cold junctions located on the frame; and signal processing circuitry on the frame and electrically interconnected with the thermopiles through the metal conductors defined by the first metal layer, the thermopiles being interlaced so that the output of a first of the thermopiles increases with increasing temperature difference between the hot and cold junctions thereof, and so that the output of a second of the thermopiles decreases with increasing temperature difference between the hot and cold junctions thereof.