Solid state imaging device

Abstract

A mixing of color that follows mixing of horizontally adjoining information charges corresponding to different colors is minimized during an operation for adding information charges of a plurality of pixels in a horizontal direction and during a high-speed horizontal transfer operation in a horizontal CCD shift register of a CCD image sensor. An impurity is used for forming barrier regions having a shallow channel potential among the barrier regions and storage regions that constitute transfer stages of the horizontal CCD shift register. The concentration of the impurity is established separately in a main portion, which is composed of transfer stages that are connected to the output ends of vertical CCD shift registers, and in a dummy portion, which connects the main portion with an output section and has a width that gradually decreases towards the output section. The barrier potential is therefore also established separately in the main portion and the dummy portion. The barrier potential is set to be high in the main portion, and the overflow of information charges into adjoining wells is minimized during the addition operation. The transfer length may be longer in the dummy portion, in which the barrier potential is limited and the fringe electric field is increased, ensuring efficient transfer during high-speed horizontal transfer.

Description

technical field [0001] The present invention relates to a solid-state imaging device including a horizontal CCD shift register, and more particularly to a technique for improving the characteristics of information charge horizontal transfer operation. Background technique [0002] In recent years, imaging devices such as digital still cameras and video cameras incorporating solid-state imaging elements such as CCD image sensors have been widely used. In the CCD image sensor, for example, there is a structure of a frame transfer type or an interlace transfer type. [0003] FIG. 5 is a configuration diagram of a frame transfer system CCD image sensor 2 . The CCD image sensor 2 is configured to include an imaging unit 2i, a storage unit 2s, a distribution unit 2t, a horizontal transfer unit 2h, and an output unit 2d. The imaging unit 2i, the storage unit 2s, and the distribution unit 2t are each composed of a plurality of vertical CCD shift registers arranged horizontally. ...

AI Technical Summary

Problems solved by technology

However, due to  B with  Δ The sum is determined according to the amplitude of the transmission clock. Therefore, in the case where the amplitude of the transmission clock is required to be reduced from the perspective of low power consumption, etc.,  B with  Δ become a compromise relationship, unable to increase both at the same time

Therefore, there is a problem that it is difficult to achieve high-speed horizontal transmission while ensuring good image quality in which color mixing is suppressed.

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