Solid state imaging device, method for driving the same and camera using the same

Abstract

In making solid state imaging devices smaller and increasing their number of pixels, it is desirable to increase the charge amount that can be handled per unit area of the transfer portions. It is possible to achieve this by making the insulating film thinner, but this leads to electric fields in the semiconductor substrate that are too strong, and causes problems such as the generation of noise and the deterioration of the transfer efficiency. This invention relaxes potential steps in the transfer region by applying, when a signal charge 1 is being read out (t=t 2 ), a high voltage to the electrode 43 for reading out the signal charge, a low voltage to at least one of the electrodes 41, 45 - 47 for preventing unnecessary mixing of signal charges, and an intermediate voltage between the high voltage and the low voltage to the electrodes 42 and 44 , which are adjacent to the electrode 43 to which the high voltage is applied.

1 - 28 . (canceled)  
   
   
       29 . A method for driving a solid state imaging device comprising a plurality of light-receiving portions and a transfer portion for reading out signal charges accumulated in the light-receiving portions and transferring the signal charges, wherein six or more electrodes constitute a unit in the transfer portion, and the light-receiving portions are divided into a plurality of groups, 
 the method comprising:    applying a read-out voltage to each of the groups with different timings when the signal charges accumulated in the light-receiving portions are read out; and    applying a voltage φVM between the read-out voltage φVH and a barrier voltage φVL to all electrodes that are adjacent to the electrodes to which the read-out voltage has been applied.