Patent ID: 7893404
Filing Date: 2011-02-22
Classification: G01J,G01N,H04N

Abstract:
1. An electromagnetic wave sensor comprising: a semiconductor substrate having a recess formed on a surface thereof; a cell portion; and a supporting portion having wiring portions electrically connected to the cell portion and supporting the cell portion in or on the recess; the cell portion comprising: an antenna portion having a plurality of antenna elements, for detecting incident electromagnetic waves and converting the electromagnetic waves into electrical signals; an electrical resistor portion disposed below the antenna portion and electrically connected to each of the plurality of antenna elements, for converting electrical energy corresponding to the electrical signals into Joule heat to change the temperature of the cell portion; and a thermoelectric conversion element electrically connected to the wiring portions, electrically insulated from the antenna portion and the electrical resistor portion, thermally connected to the electrical resistor portion, and for detecting the temperature change of the cell portion to convert the temperature change into electrical signals, and wherein a capacitor electrically formed by a gap between the plurality of antenna elements and the electrical resistor portion form a parallel circuit electrically coupled to the antenna portion, and the plurality of antenna elements are formed so that the impedance of the antenna portion and the impedance of the parallel circuit are matched for electromagnetic waves having a predetermined frequency, but the impedance is not matched for higher harmonics of electromagnetic waves having the predetermined frequency.