Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
135 words
A solid state image sensor comprising a plurality of row lines; a plurality of column lines; a plurality of pixels, each pixel comprising a normally-on type static induction transistor having gate, source and drain and a vertical type control transistor having a vertical source-drain passage connected to said gate of static induction transistor, said gate storing photocarriers induced by incident light; means for scanning the pixels to readout an image signal by selectively making conductive the static induction transistors; and means for selectively making conductive one or more vertical type control transistors of pixels which are not selected by the scanning means, and for discharging through the source-drain passages of the vertical type control transistors of non-selected pixels excess amounts of stored photocarriers over a pinch-off voltage of the static induction transistors of non-selected pixels.
Claim 2
Dependent Claim
135 words
A solid state image sensor comprising a plurality of row lines; a plurality of column lines; a plurality of pixels, each pixel comprising a normally-on type static induction transistor having gate, source and drain and a vertical type control transistor having a vertical source-drain passage connected to said gate of static induction transistor, said gate storing photocarriers induced by incident light; means for scanning the pixels to readout an image signal by selectively making conductive the static induction transistors; and means for selectively making conductive one or more vertical type control transistors of pixels which are not selected by the scanning means, and for discharging through the source-drain passages of the vertical type control transistors of non-selected pixels excess amounts of stored photocarriers over a pinch-off voltage of the static induction transistors of non-selected pixels.
Claim 3
Dependent Claim
40 words
A solid state image sensor according to claim 1, wherein said static induction transistors and vertical type control transistors of pixels are formed on the same semiconductor body and are arranged at cross points of the row and column lines.
Claim 4
Dependent Claim
78 words
A solid state image sensor according to claim 2, wherein said discharging means comprises a reset line to which control gate electrodes of vertical type control transistors of all the pixels are commonly connected, and overflow drain to which the source-drain passages of vertical type control transistors of all the pixels are commonly connected, and means for applying a reset signal to said reset line during a horizontal blanking period to discharge the photocarriers into said overflow drain.
Claim 5
Dependent Claim
39 words
A solid state image sensor according to claim 3, wherein said reset signal has such a value that a surface potential generated below the control gate electrode is substantially equal to the pinch-off voltage of the static induction transistor.
Claim 6
Dependent Claim
31 words
A solid state image sensor according to claim 3, wherein during the horizontal blanking period a row selection signal has a value smaller than a value during a signal readout period.
Claim 7
Dependent Claim
94 words
A solid state image sensor according to claim 2, wherein said discharging means comprises a plurality of additional column lines to which control gate electrodes of vertical type control transistors of pixels arranged in respective columns are commonly connected, an overflow drain to which the source-drain passages of vertical type control transistors of all the pixels are commonly connected, and a resetting horizontal scanning circuit for applying successively reset signals to said additional column lines in synchronism with signal readout by means of said scanning means to discharge the photocarriers into the overflow drain.
Claim 8
Dependent Claim
30 words
A solid state image sensor according to claim 6, wherein discharge of photocarriers into the overflow drain for a pixel is effected immediately after the relevant pixel has been readout.
Claim 9
Dependent Claim
45 words
A solid state image sensor according to claim 6, wherein discharge of photocarriers into the overflow drain for a pixel is effected prior to a signal readout for the relevant pixel by a time period equal to any integer multiple of a horizontal scanning period.
Claim 10
Dependent Claim
94 words
A solid state image sensor according to claim 2, wherein said discharging means comprises a plurality of additional row lines to which control gate electrodes of vertical type control transistors of pixels arranged in respective rows are commonly connected, an overflow drain to which the source-drain passages of vertical type control transistors of all the pixels are commonly connected, and a resetting vertical scanning circuit for applying successively reset signals to said additional row lines in synchronism with signal readout by means of said scanning means to discharge the phptocarriers into the overflow drain.
Claim 11
Dependent Claim
34 words
A solid state image sensor according to claim 9, wherein discharge of photocarriers into the overflow drain for pixels belonging to a row line is effected immediately after the relevant pixels have been readout.
Claim 12
Dependent Claim
36 words
A solid state image sensor according to claim 9, wherein discharge of photocarriers into the overflow drain for pixels belonging to a row line is effected while pixels belonging to a next row line are readout.
Claim 13
Dependent Claim
27 words
A solid state image sensor according to claim 2, wherein said vertical type control transistor is formed along an isolation region separating adjacent pixels from each other.
Claim 14
Dependent Claim
57 words
A solid state image sensor according to claim 12, wherein said isolation region comprises a recess formed in the semiconductor body, and said vertical type control transistor comprises a first region formed in the recess, a second region formed in a bottom of the recess and a third region formed in the semiconductor body beside the recess.
Claim 15
Dependent Claim
73 words
A solid state image sensor according to claim 13, wherein said first region comprises a gate oxide film formed on an inner suface of the recess, a gate electrode formed on the gate oxide film in the recess, said second region comprises a diffusion layer formed in the bottom of the recess, and said third region comprises a diffusion region which constitutes one of the source and drain of the static induction transistor.