Integrated circuit and method of forming sealed trench junction termination

A method of making a semiconductor device, comprising:

• providing a substrate including semiconductor material of a first conductivity type;
• forming a buried semiconductor layer of a second conductivity type in the substrate;
• forming a first semiconductor layer of the second conductivity type over the buried semiconductor layer;
• forming a trench through the first semiconductor layer and through the buried semiconductor layer;
• forming a first insulating layer on a wall of the trench;
• depositing an insulating material in the trench;
• forming a discrete device by,
• (a) doping the first semiconductor layer to form a second semiconductor layer of the first conductivity type, and
• (b) forming a third semiconductor layer of the second conductivity type in the second semiconductor layer;
• forming a second insulating layer in contact with the first semiconductor layer, second semiconductor layer, third semiconductor layer, first insulating layer, and insulating material;
• forming a first metal layer directly above and abutting the second semiconductor layer;
• and
• forming a second metal layer directly above and abutting the third semiconductor layer, wherein the insulating material in the trench surrounds the discrete device.