Patent ID: 6781108
Filing Date: 2004-08-24
Classification: H01L,H03F

Abstract:
A photosensor-amplifier device comprising:a photoelectric conversion element that converts an optical signal into an electric signal; a first electrode connected electrically to the photoelectric conversion element and by which the electric signal is extracted from the photoelectric conversion element; a second electrode formed on the photoelectric conversion element in close proximity to the first electrode in such a way that the electric signal does not pass through the second electrode; an amplifier circuit that has a first input terminal and a second input terminal and that amplifies and then outputs a difference between electric signals fed to the first and second input terminals; a first bonding wire that connects the first electrode to the first input terminal; and a second bonding wire having substantially an identical length as the first bonding wire and laid side-by-side substantially parallel to the first bonding wire, the second bonding wire that connects the second electrode to the second input terminal. wherein each of the first electrode, the second electrode, the first input terminal, and the second input terminal are arranged in a substantially rectangular shape in plan view such that the first and second bonding wires receive electromagnetic noise in substantially equal degrees so that noise signals induced in the first and second bonding wires are made substantially equal to each other, the photosensor-amplifier device further comprising: a substrate on which a first element formed as the photoelectric conversion element and a second element formed as the amplifier circuit are mounted; and a first conductor pattern and a second conductor pattern formed on the substrate, wherein the first bonding wire comprises a first portion and a second portion, the first portion of the first bonding wire connects the first electrode to the first conductor pattern, and the second portion of the first bonding wire connects the first conductor pattern to the first input terminal, the second bonding wire comprises a first portion and a second portion, the first portion of the second bonding wire connects the second electrode to the second conductor pattern, and the second portion of the second bonding wire connects the second conductor pattern to the second input terminal.