Patent ID: 8338902
Filing Date: 2012-12-25
Classification: G01J,H01L

Abstract:
1. An uncooled infrared image sensor comprising: a semiconductor substrate; a plurality of pixel cells formed in a first region on the semiconductor substrate, the first region having first concave portions arranged in a matrix form in a surface of the semiconductor substrate, the pixel cells corresponding to the arrangement of the first concave portions and being located above the first concave portions, each of the pixel cells including: a first infrared absorption film absorbing an incident infrared ray and converting the absorbed infrared ray into heat; and a first heat sensitive element generating an electrical signal by detecting the heat from the first infrared absorption film; a reference pixel cell formed in a second region on the semiconductor substrate and corresponding to each row or each column of the pixel cells, the reference pixel cell including: a second infrared absorption film absorbing an incident infrared ray and converting the absorbed infrared ray into heat; and a second heat sensitive element generating an electrical signal by detecting the heat from the second infrared absorption film, the second heat sensitive element having the same characteristics as characteristics of the first heat sensitive element; a supporting unit formed for each of the pixel cell and supporting a corresponding pixel cell above the first concave portions, the supporting unit including: a first interconnect having one end connected to one end of the first heat sensitive element; and a second interconnect having one end connected to the other end of the first heat sensitive element; and an interconnect unit formed for each reference pixel cell, the interconnect unit including: a third interconnect having one end connected to one end of the second heat sensitive element; and a fourth interconnect having one end connected to the other end of the corresponding second heat sensitive element, the third and fourth interconnects of the interconnect unit having the same electrical resistance as electrical resistance of the first and second interconnects, the reference pixel cell being in contact with the semiconductor substrate, a second concave portion being formed below the interconnect unit and being located in the surface of the semiconductor substrate.