US 6,388,278 B1Granted

Solid state image pickup device and its driving method

AssigneeFuji Photo Film Co., Ltd.

InventorsNobuo Suzuki, Kazuyuki Masukane

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Abstract

IT-CCD has a number of photoelectric conversion elements disposed in a pixel shift layout in a plurality of rows and columns, a plurality of vertical transfer CCDs for transferring signal charges accumulated in the photoelectric conversion elements toward a horizontal transfer CCD in a zigzag way, and readout gate regions for controlling for corresponding photoelectric conversion elements to read the signal charges accumulated in the photoelectric conversion elements to the vertical transfer CCDs. In manufacturing such IT-CCD, for twos of a plurality of photoelectric conversion element columns, a vertical transfer CCD is provided in an area in plan view between the two photoelectric conversion element columns, and a plurality of charge transfer stages constituting a adjusting portion are formed downstream of the downstream ends of the vertical transfer CCDs. The horizontal transfer CCD can be formed easily without using highly sophisticated ultra fine patterning techniques and power consumption of the horizontal transfer CCD can be suppressed low.

Claims13

Dependent claims

A solid state image pickup device, comprising:

a semiconductor substrate;
a number of photoelectric conversion elements disposed on a surface of the semiconductor substrate in a plurality of columns and rows, a photoelectric conversion element column and a photoelectric conversion element row each being composed of a plurality of photoelectric conversion elements, a plurality of photoelectric conversion elements of an even column being shifted in a column direction by about a half of the pitch between adjacent photoelectric conversion elements in each photoelectric conversion element column, from a plurality of photoelectric conversion elements of an odd column, and a plurality of photoelectric conversion elements of an even row being shifted in a row direction by about a half of the pitch between adjacent photoelectric conversion elements in each photoelectric conversion element row, from a plurality of photoelectric conversion elements of an odd row;
charge transfer channels each provided for two photoelectric conversion element columns and formed in the surface of the semiconductor substrate in an area in plan view between the two photoelectric conversion element columns, said charge transfer channel extending as a whole along a direction of the photoelectric conversion element column and having a zigzag shape;
a plurality of transfer electrodes formed on the semiconductor substrate, traversing in plan view each of said charge transfer channels, said transfer electrode having transfer path forming areas same in number as said charge transfer channels, the transfer path forming area forming one charge transfer stage in a cross area in plan view with a corresponding charge transfer channel, adjacent two transfer electrodes with one photoelectric conversion element row being interposed therebetween repeating in plan view divergence and convergence and surrounding in plan view each photoelectric conversion element in the photoelectric conversion element row of an even or odd row to define photoelectric conversion element region, said transfer electrode extending as a whole along a direction of the photoelectric conversion element row;
a readout gate region provided for each photoelectric conversion element in the surface of the semiconductor substrate to be contiguous to the photoelectric conversion element and to a corresponding charge transfer channel, said readout gate region corresponding to the photoelectric conversion element of the even row and said readout gate region corresponding to the photoelectric conversion element of the odd row being covered in plan view with different transfer electrodes;
and
an adjusting portion formed downstream of downstream ends of said charge transfer channels, said adjusting portion including a plurality of charge transfer stages for adjusting a phase of signal charges transferred from each of said charge transfer channels.

4 more elements

A driving method for a solid state image pickup device comprising:

a semiconductor substrate;
a number of photoelectric conversion elements disposed on a surface of the semiconductor substrate in a plurality of columns and rows, a photoelectric conversion element column and a photoelectric conversion element row each being composed of a plurality of photoelectric conversion elements, a plurality of photoelectric conversion elements of an even column being shifted in a column direction by about a half of the pitch between adjacent photoelectric conversion elements in each photoelectric conversion element column, from a plurality of photoelectric conversion elements of an odd column, and a plurality of photoelectric conversion elements of an even row being shifted in a row direction by about a half of the pitch between adjacent photoelectric conversion elements in each photoelectric conversion element row, from a plurality of photoelectric conversion elements of an odd row;
charge transfer channels each provided for two photoelectric conversion element columns and formed in the surface of the semiconductor substrate in an area in plan view between the two photoelectric conversion element columns, said charge transfer channel extending as a whole along a direction of the photoelectric conversion element column and having a zigzag shape;
a plurality of transfer electrodes formed on the semiconductor substrate, traversing in plan view each of said charge transfer channels, said transfer electrode having transfer path forming areas same in number as said charge transfer channels, the transfer path forming area forming one charge transfer stage in a cross area in plan view with a corresponding charge transfer channel, adjacent two transfer electrodes with one photoelectric conversion element row being interposed therebetween repeating in plan view divergence and convergence and surrounding in plan view each photoelectric conversion element in the photoelectric conversion element row of an even or odd row to define photoelectric conversion element region, said transfer electrode extending as a whole along a direction of the photoelectric conversion element row;
a readout gate region provided for each photoelectric conversion element in the surface of the semiconductor substrate to be contiguous to the photoelectric conversion element and to a corresponding charge transfer channel, said readout gate region corresponding to the photoelectric conversion element of the even row and said readout gate region corresponding to the photoelectric conversion element of the odd row being covered in plan view with different transfer electrodes;
and an adjusting portion formed downstream of downstream ends of said charge transfer channels, said adjusting portion including a plurality of charge transfer stages for adjusting a phase of signal charges transferred from each of said charge transfer channels, the driving method comprising the steps of:
reading the signal charges accumulated in each photoelectric conversion element of at least one photoelectric conversion element row, to the charge transfer channel corresponding to the photoelectric conversion element via the readout gate region contiguous to the photoelectric conversion element, during one vertical blanking period;
and
converting the signal charges read to the charge transfer channel into an image signal and outputting the image signal, during a period after the one vertical blanking period and before a next vertical blanking period.

6 more elements

Dependencies are inferred from the claim text.