Method for making an isolated sidewall capacitor having a compound plate electrode

A capacitor structure is provided, with a first conductor on top of a substrate having at least one layer of dielectric material thereon; a first non-conductor on top of and substantially in register with the first conductor, the first conductor and first non-conductor having a first opening formed therein; a second conductor, in electrical contact with the first conductor, formed on the sidewalls of the first opening; a non-conductive sidewall spacer formed in the first opening and contacting the second conductor, the non-conductive sidewall spacer having a second opening formed therein; and a third conductor formed in the second opening.