Buried channel charge coupled apparatus

Claim 2

A buried channel charge coupled device of the type adapted for storing and sequentially transferring mobile charge carriers coupled to locally induced internal potential wells comprising a semiconductive storage layer of a first conductivity type overlying a barrier layer; an insulating layer overlying the storage layer; contact means for biasing said storage layer in order to deplete said storage layer of mobile charge carriers; a plurality of electrodes disposed over and forming a path along the surface of the insulating layer; detection means at one end of said path for detecting mobile charge carriers in said storage layer; means in response to two-phase voltages of sufficient magnitude applied between the electrodes and the storage layer for causing under each electrode the formation of an asymmetric potential well internal to the storage layer, the asymmetry in the potential wells being sufficient in response to the twophase voltages for causing mobile charge carriers to propagate unidirectionally in the bulk of said storage layer toward said detection means.

Claim 3

A device as recited in claim 1 wherein the barrier layer is a semiconductor of the opposite type conductivity forming a PN junction with the storage layer.

Claim 4

Apparatus as recited in claim 1 wherein the means for causing under each electrode an asymmetric potential well includes in each eLectrode a first conductive portion and a second conductive portion wherein the first conductive portion is the portion of the electrode farthest away from said detection means, the first conductive portion being spaced at a substantially lesser distance from the surface of the storage medium than is the second portion.

Claim 5

Apparatus as recited in claim 1 wherein the means for causing under each electrode an asymmetric potential well includes, in that portion of the storage layer under the first conductive portion of each electrode, a concentration of immobile charge substantially less than the concentration of immobile charge underneath the second portion of said electrode wherein the first conductive portion is the portion of the electrode farthest away from said detection means.

Claim 6

Apparatus as recited in claim 4, wherein the mobile charge carriers are of a first polarity and the immobile charge is of the opposite polarity.

Claim 7

Apparatus as recited in claim 1 wherein the semiconductive storage layer includes silicon and the insulating layer includes silicon oxide.

Claim 8

Apparatus as recited in claim 1 further including means for providing to the electrodes two-phase voltages of polarity and magnitude sufficient for causing the mobile charge carriers to propagate unidirectionally.

Claim 9

A buried channel charge coupled device of the type adapted for storing and sequentially transferring charge carriers coupled to locally induced internal potential wells comprising a first semiconductive layer of one conductivity type; a semiconductive storage layer of the opposite conductivity type overlying the first layer and forming a PN junction therewith; an insulating layer overlying the storage layer; input means associated with a first position on said storage layer; output means associated with a second position along said storage layer; contact means for biasing said storage layer in order to deplete said storage layer of mobile charge carriers; and a plurality of electrodes disposed over the surface of the insulating layer and forming a path between the input means and the output means, the improvement being that each of said electrodes includes a first conductive portion and a second conductive portion, the first conductive portion being the one closest to the input means and being spaced at a substantially lesser distance from the surface of the storage layer than is the second portion.

Claim 10

A buried channel charge coupled device of the type adapted for storing and sequentially transferring charge carriers coupled to locally induced internal potential wells comprising a first semiconductive layer of one conductivity type; a semiconductive storage layer of the opposite conductivity type overlying the first layer and forming a PN junction therewith; an insulating layer overlying the storage layer; input means associated with a first position on said storage layer; output means associated with a second position along said storage layer; contact means for biasing said storage layer in order to deplete said storage layer of mobile charge carriers; and a plurality of electrodes disposed over the surface of the insulating layer and forming a path between the input means and the output means, the improvement being that each of said electrodes includes a first conductive portion and a second conductive portion, the first conductive portion being the one closest to the input means and being spaced at a substantially lesser distance from the surface of the storage layer than is the second portion.

Claim 11

A buried channel charge coupled device of the type adapted for storing and sequentially transferring charge carriers coupled to locally induced internal potential wells comprising a first semiconductive layer of one conductivity type; a semiconductive storage layer of the opposite conductivity type overlying the first layer and forming a PN junction therewith; an insulating layer overlying the storage layer; input means associated with a first position along said storage layer; output means associated with a second position along said storage layer; contact means for biasing said storage layer in order to deplete said storage layer of mobile charge carriers; and a plurality of electrodes disposed over the surface of the insulating layer and forming a path between the input means and the output means, each of said electrodes including a first conductive portion and a second conductive portion, the first conductive portion being the one closest to the input means and that portion of the storage layer underneath the first portion including a concentration of immobile charge of the same polarity as the storage layer substantially less than the concentration of immobile charge of the same polarity as the storage layer underneath the second portion.

Claim 12

A buried channel charge coupled device of the type adapted for storing and sequentially transferring charge carriers coupled to locally induced internal potential wells comprising a first semiconductive layer of one conductivity type; a semiconductive storage layer of the opposite conductivity type overlying the first layer and forming a PN junction therewith; an insulating layer overlying the storage layer; input means associated with a first position along said storage layer; output means associated with a second position along said storage layer; contact means for biasing said storage layer in order to deplete said storage layer of mobile charge carriers; and a plurality of electrodes disposed over the surface of the insulating layer and forming a path between the input means and the output means, each of said electrodes including a first conductive portion and a second conductive portion, the first conductive portion being the one closest to the input means and that portion of the storage layer underneath the first portion including a concentration of immobile charge of the same polarity as the storage layer substantially less than the concentration of immobile charge of the same polarity as the storage layer underneath the second portion.