Charge-coupled buried-channel device with high-resistivity gate electrodes

Claim 1

A charge-coupled buried-channel semiconductor device having an MIS element, which comprises: a monocrystalline semiconductor body having a major surface; a comparatively thin dielectric layer on said major surface and forming the gate dielectric of said MIS element; a gate electrode of doped semiconductor material on said thin dielectric layer for influencing the surface potential in the semiconductor body; means for electrically decoupling said gate electrode from said semiconductor body, said means comprising a high-resistivity part of said gate electrode adjoining said gate dielectric and having a sufficiently low doping concentration and a conductivity type such that, during operation of the device, while avoiding breakdown, a depletion layer can be formed which extends from the gate dielectric into the high-resistivity part of said gate electrode; a plurality of similar gate electrodes on the thin dielectric layer at a distance from each other, and a subjacent channel region, said plurality of similar gate electrodes, together with said gate electrode, comprising a row of clock electrodes to which clock voltages can be applied for sequentially storing/transferring packets of charge carriers in the subjacent channel region, said clock electrodes being provided in the form of a continuous layer of polycrystalline silicon divided into a row of high-resistivity parts which form the clock electrodes of the charged-coupled device, which are provided with means for applying clock voltages, and which are separated by intermediate electrically-floating parts of a first conductivity type; a surface region of said first conductivity type which is formed in the semiconductor body, adjoining the surface and forming the channel region of the charge-coupled device, at least the high-resistivity parts of the clock electrodes being of a second, opposite conductivity type and the surface region being limited on its side remote from the surface by an isolating p-n junction and having a thickness of at most 1.0 μm.