CHARGE-COUPLED DEVICE

摘要

The invention relates to a CCD of the buried-channel type comprising a charge-transport channel in the form of a zone (12) of the first conductivity type, for example the n-type, in a well (13) of the opposite conductivity type, in the example the p-type. In order to obtain a drift field in the channel below one or more gates (9, 10a) to improve the charge transfer, the well is provided with a doping profile, so that the average concentration decreases in the direction of charge transport. Such a profile can be formed by covering the area of the well during the well implantation with a mask, thereby causing fewer ions to be implanted below the gates (9, 10a) than below other parts of the channel. By virtue of the invention, it is possible to produce a gate (10a) combining a comparatively large length, for example in the output stage in front of the output gate (9) to obtain sufficient storage capacity, with a high transport rate.