| 摘要 |
PURPOSE:To improve an opening rate and sensitivity, by accumulating carriers in a control electrode region composed of a main electrode region formed of a conductivity type region, and of a control electrode region of a conductivity type opposite to the one of the main electrode region, and by burying the main electrode region in the control electrode region. CONSTITUTION:An SiO2 film is made to grow on an N-type silicon substrate 1, and a part other than a region wherein an element isolation region 3 is formed is etched. After a polycrystalline silicon film 13 is formed on the whole surface, the polycrystalline silicon film 13 is left behind only on the lateral side of the SiO2 film 14, and a thermal oxidation film 16 is formed. Thereafter an Si3N4 film 16 is formed, a region wherein a pulse impression electrode 12 is buried is patterned and etched to form a groove portion 17. Since a sharp step is formed in the groove portion 17, a lift-off method can be applied with ease. Afterwards, a resist is exfoliated, dope polysilicon is buried, and an interlayer insulation film 18 is formed. After an NSG film or a PSG film is deposited, an emitter is patterned, an N<+> region is formed, and a wiring portion is buried in a contact hole. This constitution enables an improvement in an opening rate per cell of a photosensor element.
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