T-shaped contacts for semiconductor device

摘要

A transistor, planar or non-planar (e.g., FinFET), includes T-shaped contacts to the source, drain and gate. The top portion of the T-shaped contact is wider than the bottom portion, the bottom portion complying with design rule limits. A conductor-material filled trench through a multi-layer etching stack above the transistor provides the top portions of the T-shaped contacts. Tapered spacers along inner sidewalls of the top contact portion prior to filling allow for etching a narrower bottom trench down to the gate, and to the source/drain for silicidation prior to filling.

主权项

1. A method, comprising:
providing a starting semiconductor structure, the structure comprising a semiconductor substrate, an active layer with one or more active regions, at least one gate over a portion of the active layer, and a layer of filler material on both sides of the at least one gate; creating a multi-layer etching stack over the starting structure, the multi-layer etching stack comprising a dielectric layer between top and bottom hard mask layers, wherein only the dielectric layer and bottom hard mask layers are used as etch stops; and creating T-shaped contacts thru the multi-layer etching stack to the one or more active regions and the at least one gate, wherein each T-shaped contact uses a single fill of bulk conductive material.