Solid-state CCD imaging device with transfer gap voltage controller

A solid-state charge transfer device comprising:

• a semiconductive substrate;
• semiconductive photosensitive layers arranged on the substrate to define an array of rows and columns of pixels, for generating signal charge carriers representing an incident image;
• a plurality of first semiconductive charge transfer channel layers extending in a first direction in said substrate, each of the first channel layers being close to a corresponding one of the columns of pixels;
• first electrode means overlying said first channel layers with gaps between adjacent ones of said first electrode means along the first direction, for sequentially transferring signal charge carriers toward output stages of said first channel layers in response to a first clock signal, said first electrode means including an array of first transfer electrodes arranged in a single conductive layer above said substrate;
• a second semiconductive charge transfer channel layer extending in a second direction in said substrate to be coupled to the output stages of said first channel layers, and having an output;
• second electrode means overlying the second channel layer with gaps between adjacent ones of said second electrode means along the second direction, for causing signal charge carriers sent from said first channel layers to sequentially transfer towards the output of said second channel layer in response to a second clock signal, said second electrode means including an array of second transfer electrodes arranged in a single conductive layer above said substrate;
• amplifier means coupled to said output of said second channel layer, for amplifying and externally outputting signal charge carriers transferred thereto;
• and
• gap-potential controller means associated with at least one of the first and second electrode means, for adjusting a potential in certain adjacent channel regions located below the gaps of a channel layer or layers associated with said at least one electrode means to be set at intermediate levels between "high" and "low" level potentials of said channel layer or layers, said intermediate levels being potentially different from each other so as to enhance the flow of signal charge carriers, said gap-controller means comprising a charge accelerating conductive layer at least partially overlying at least one of said first and second electrode means and providing the intermediate levels in response to a DC voltage signal externally supplied thereto.

A solid-state imaging device comprising:

• a substrate;
• photosensitive first semiconductor layers arranged as pixel sections;
• transfer means arranged in said substrate and coupled to said pixel sections, for transferring charge carriers read out from said pixel sections in a predetermined direction;
• said transfer means including (i) a second semiconductive layer in said substrate, for defining a charge transfer channel section, and (ii) an array of spaced-apart transfer electrodes arranged in a single conductive layer insulatively disposed at a first level above said substrate and extending in said direction with gap sections between adjacent ones of said transfer electrodes, for defining a plurality of charge-transfer channel regions located below said transfer electrodes in said second semiconductive layer;
• said second semiconductive layer having gap regions located below said gap sections;
• and
• gap potential control means including a charge accelerating conductive layer arranged at a second level over said substrate to insulatively overlie said transfer electrodes and said gap sections among them, for receiving a DC voltage signal externally supplied thereto, and for, when the charge carriers are flowing through a certain charge-transfer channel region in said second semiconductive layer, potentially controlling said gap regions in such a manner that a front gap region is potentially greater than a rear gap region of a certain charge-transfer channel region through which the charge carriers read out from said pixel sections are presently flowing are set at first and second intermediate potential levels between a maximum potential and a minimum potential defined in said second semiconductive layer, thereby to accelerate the forward flow of charge carriers, wherein said charge accelerating conductive layer has an elongated layer section extending in said predetermined direction.