Method for fabricating a trench contact to a deep trench capacitor having a polysilicon filling
AssigneeInfineon Technologies AG
InventorsMartin Schrems, Dietmar Temmler, Andreas Wich-Glasen
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Abstract
The instant invention is a method for fabricating a trench contact to a deep trench capacitor with a polysilicon filling in a trench hole formed in a silicon substrate. An epitaxy process is performed to selectively grow silicon above the polysilicon filling in the trench hole. An opening leading to the polysilicon filling is anisotropically etched into the epitaxially grown silicon. The opening has lateral dimensions that are smaller than those of the polysilicon filling, and the opening is filled with polysilicon.
Claims11
A method for fabricating a trench contact to a deep trench capacitor with a polysilicon filling in a trench hole formed in a silicon substrate, which comprises:
- performing an epitaxy process to selectively grow silicon above the polysilicon filling in the trench hole;
- anisotropically etching an opening in the epitaxially grown silicon such that the opening leads to the polysilicon filling and such that the opening has lateral dimensions that are smaller than those of the polysilicon filling;
- and
- filling the opening with polysilicon.
Dependencies are inferred from the claim text.