High voltage capacitor and magnetron

A high voltage capacitor, comprising:

• at least one grounding metal having a raised portion provided with a hole and an internal space continuous with said hole;
• at least one capacitor including a dielectric ceramic material provided with at least one through hole and electrodes at surfaces where said at least one through hole opens, with one of said electrodes secured onto said raised portion;
• at least one conductor passing through said hole of said grounding metal and said at least one through hole of said at least one capacitor, and being electrically connected to another of said electrodes;
• at least one insulating tube covering said conductor;
• at least one insulating cover having one end inserted in said internal space;
• and
• an insulating resin filling spaces around said at least one conductor, around said raised portion and in said internal space, wherein:
• said one end of said insulating cover faces an inner surface of said internal space of said raised portion over a gap and said insulating resin fills said gap;
• and
• said one end of said insulating cover is provided with a plurality of projections facing opposite said inner surface of said internal space of said raised portion.