Method of manufacturing a crater-style capacitor for high-voltage radio-frequency applications

A method of making a high-voltage capacitor, comprising steps of:

• (a) forming a crater in a first surface of dielectric body, the crater having a bottom and sidewall surfaces and sloped to form a smooth liftoff curve between the bottom and the sidewall surfaces;
• (b) depositing an electrically conductive material on the bottom surface, the liftoff curve, and a portion of the sidewall surface to define an input electrode, the input electrode defining an upper electrode edge on the sidewall surface;
• (c) depositing a first electrically conductive material on a second surface of the dielectric body opposite the first surface and spaced from said bottom surface to form an output electrode, the output electrode defining a sampling capacitor between the input electrode and the output electrode;
• (d) after said step (c), depositing a second electrically conductive material on the second surface of the dielectric body to form a guard electrode, the guard electrode defining a guard capacitor between the input electrode and the guard electrode, the guard electrode completely encircling the output electrode;
• and
• (e) heating the dielectric body to bake on the input electrode, the output electrode, and the guard electrode.