SOI island in a power semiconductor device
AssigneeInfineon Technologies AG
InventorsAlexander Philippou, Anton Mauder
Life of this patent
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Abstract
A power semiconductor device includes a semiconductor-on-insulator island having a semiconductor region and an insulation structure, the insulation structure being formed by an oxide and separating the semiconductor region from a portion of a semiconductor body of the power semiconductor device. The insulation structure includes a sidewall that laterally confines the semiconductor region; a bottom that vertically confines the semiconductor region; and a local deepening that forms at least a part of a transition between the sidewall and the bottom, wherein the local deepening extends further along the extension direction as compared to the bottom.
Claims14
A method of producing a semiconductor-on-insulator island in a power semiconductor device, the method comprising:
- providing a semiconductor body with a plurality of trenches, each trench including an insulator, wherein the plurality of trenches includes first trenches designated for a pattern-collapse processing step and a border trench arranged adjacent to at least one of the first trenches, the border trench having a first sidewall facing the at least one first trench and an opposite second sidewall;
- providing a mask having an opening exposing a first section that comprises each of the first sidewall of the border trench and the first trenches, and wherein the mask covers a second section including at least the second sidewall of the border trench;
- removing the insulator included in the first section being exposed by the opening;
- and
- subjecting the first section to the pattern-collapse-processing step while maintaining the insulator at the second sidewall of the border trench, thereby transforming the first trenches into at least one buried cavity.
Dependencies are inferred from the claim text.