| 摘要 |
PURPOSE:To eliminate adverse effect to the operation of a signal processing system circuit and to improve an S/N ratio by providing an absorbing region for absorbing carriers, which leak out of a photosensor, between the photosensor and a signal processing element. CONSTITUTION:Carriers 110, which are generated by a light 109' to reach a p-type semiconductor substrate 104 out of incident lights 109 to be incided in a photo diode 101 through the opening part of an oxide film 111 and leak out of the photo diode 101, are absorbed in an N<-> epitaxial layer 106 by a drift due to the inverse bias of an absorbing region 103 consisting of a diode constituted of the substrate 104 and an N-type epitaxial layer 106. Thereby, as the carriers 110, which leak out of the photo diode 101, do not reach up to a signal processing bipolar element 102, adverse effect is never exerted on the operation of a signal processing system circuit and the deterioration of an S/N ratio is prevented. |
