Sensor unit and biosensor

Abstract

A highly miniaturized biosensor and a sensor unit, which can meet a demand for further miniaturization. With this invention, miniaturization is possible, and the number of production steps including those for assembling individual parts can be reduced. Accordingly, mass production will be possible, and cost reduction and high reliability will be achieved. A light emitting unit ( 21 ) is disposed within a first recess ( 24 a ) formed on a semiconductor substrate ( 23 a ), and light receiving unit ( 22 ) is disposed within a second recess ( 24 b ) formed on a surface of a semiconductor substrate ( 23 b ), and a light shielding cover substrate ( 27 a ) having a first light guide section ( 25 ) is disposed so as to cover the first recess ( 24 a ), and a transparent substrate ( 29 a ) is provided on an upper side of the light shielding cover substrate ( 27 a ), and another light shielding cover substrate ( 27 b ) having the second light guiding section ( 26 ) is disposed so as to cover the second recess ( 24 b ), and a transparent substrate ( 29 b ) is provided on an upper side of the light shielding cover substrate ( 27 b ), and each light receiving surface of the light receiving elements ( 28 ) is connected to one end of corresponding one of the second light guiding sections ( 26 ) so as to conform to each other without any gap.

1 . A sensor unit which is to be included in a biosensor that measures values concerning liquid matter inside living tissue by irradiating light emitted from a light emitting unit toward the living tissue situated outside and receiving transmitted light from the living tissue by a light receiving unit, the sensor unit having a structure in which the light emitting unit is disposed within a first recess formed on a surface of a semiconductor substrate; the light receiving unit is disposed within a second recess which is another recess formed on the surface of the semiconductor substrate; a light shielding cover substrate having a light guiding section is provided so as to cover the second recess; a light receiving surface of the light receiving unit is connected to one end of the light guiding section so as to conform to each other without any gap; light emitted from the light emitting unit is irradiated toward the living tissue situated outside; and light transmitted through the living tissue passes through the light guiding section and is received by the light receiving unit. 
     
     
         2 . A sensor unit according to  claim 1 , wherein, when the light receiving unit is formed with arrayed light receiving elements, the same number of the light guiding sections as the light receiving elements are provided on the cover substrate; and the light receiving surface of the light receiving element is connected to one end of each of the light guiding sections so as to conform to each other without any gap.