Glass pass through with an additional insulator for lengthening leakage path

Claim 1

A power semiconductor component, comprising a glass part having at least one end face, a metal case part having an opening formed therein in which said glass part is disposed and sealed to said metal case part, a ceramic ring having a planar end face and an outer diameter which is larger than the opening in said metal case part, said ceramic ring being connected at said end face thereof to said at least one end face of said glass part, at least one electric conductor extending through said glass part and an opening formed in said ceramic ring, said at least one electric conductor having an outside diameter which is smaller than the diameter of the opening in said ceramic ring forming a space therebetween, and glass disposed in said space sealing said glass part and said ceramic part to said at least one electric conductor, said connection between said ceramic ring and said glass part comprising a glass fusion-melt, said end face of said ceramic ring connected to said glass part having a bevel formed at the periphery thereof extended beyond the opening in said metal case part, forming a capillary gap for said glass fusion-melt and leaving a diameter inside said bevel at the periphery which is smaller than the diameter of the opening in said metal case part.