Charge coupled semiconductor element with noise cancellation

Claim 1

A charge coupled semiconductor element comprising: a semiconductor substrate of a first conductivity type; an insulating film disposed on one surface of said substrate; first means, coupled to said substrate, for injecting charges of a polarity opposing said first conductivity type into a portion of the surface of said substrate; a first electrode disposed on said insulating film, adjacent said first means; means for applying an input gate signal to said first electrode for transferring injected charges thereunder; a predetermined number of electrodes provided on said insulating film to which shift pulses are applied, disposed next to said first electrode; second means for applying multiple phase voltage pulses to respective ones of said predetermined number of electrodes to effect the sequential transfer of charges therebeneath; third means, coupled to sAid substrate, for deriving signals corresponding to charges which have been injected into said substrate and transported along the substrate surface portion beneath said predetermined number of electrodes by said second means; an output gate electrode, disposed adjacent said third means and said predetermined number of electrodes but being separated from said first electrode by said predetermined number of electrodes; means for applying an output gate signal to said output gate electrode for effecting the transfer of charges, which have been sequentially transferred beneath said predetermined number of electrodes, to said third means; and fourth means, coupled to said third means, for substantially eliminating noise component charges generated by the shifting of charges beneath said predetermined number of electrodes and said output gate electrode from the signals derived by said third means, comprising: an array of electrodes made up of a selected number of spaced apart electrodes disposed on said insulating film apart from said predetermined number of electrodes and respectively positioned opposite the last n number of electrodes of said predetermined number of electrodes, adjacent said output gate electrode, where n corresponds to the number of said multiple phase voltage pulses, an additional electrode, disposed on said insulating film but being spaced apart from and at a position opposite said output gate electrode, additional means, coupled to said substrate adjacent said additional electrode and spaced apart from and at a position opposite said third means, for deriving signals corresponding to noise component charges which have been transported along the substrate surface portion beneath said array of electrode and said additional electrode, means for electrically connecting said additional electrode to said output gate electrode, means for electrically connecting said selected number of electrodes respectively to said last n number of said predetermined number of electrodes, and means, connected to additional means and to said third means, for differentially combining the signals derived thereby, so as to substantially cancel said noise component charges from the signals derived by said third means.