Patent ID: 6188093
Filing Date: 2001-02-13
Classification: H01L,Y02E

Abstract:
A photoelectric conversion device, comprising:(a) a first conductive-type semiconductor substrate and a first conductive-type semiconductor layer formed on said substrate;(b) a photodiode having a second conductive-type charge-accumulation region formed in the first conductive-type semiconductor layer and structured and arranged to generate and accumulate an electric charge in response to incident light;(c) a junction field-effect transistor having(i) a second conductive-type gate region formed in the first conductive-type semiconductor layer,(ii) a first conductive-type source region formed in the gate region,(iii) a first conductive-type channel region formed in the gate region, and(iv) a first conductive-type drain region formed in the first conductive-type semiconductor layer and electrically connected to the first conductive-type semiconductor substrate,the junction field-effect transistor being structured and arranged so as to output a signal corresponding to the electric charge received by the gate region from the photodiode;(d) a transfer gate having a gate electrode formed above the first conductive-type semiconductor layer separated therefrom by an insulating film and structured and arranged so as to be able to transfer the electric charge generated and accumulated by the photodiode to the gate region of the junction field-effect transistor;(e) a reset drain having a second conductive-type charge-drain region formed in the first conductive-type semiconductor layer and structured and arranged so as both to drain an excess electric charge generated by the photodiode and to control an electric potential of the gate region of the junction field-effect transistor;(f) a first overflow-control region formed in a boundary region between the charge-accumulation region of the photodiode and the charge-drain region of the reset drain in the first conductive-type semiconductor layer and structured and arranged so as to guide the excess electric charge generated by the photodiode to the charge-drain region of the reset drain; and(g) a first reset gate having a gate electrode formed above the first conductive-type semiconductor layer, separated therefrom by an insulating film, and structured and arranged so as to control the electric connection between the gate region of the junction field-effect transistor and the charge-drain region of the reset drain.