Contact structure

A semiconductor device, comprising:

• a fin structure disposed on a substrate, wherein the fin structure is located at least partially in an oxide layer;
• a gate feature that traverses the fin structure to overlay a central portion of the fin structure, wherein the gate feature comprises a gate electrode and is located in a first dielectric layer located above the oxide layer;
• a pair of source/drain features, along the fin structure, that are disposed at respective sides of the gate feature, the pair of source/drain features located partially in the first dielectric layer and partially in the oxide layer;
• and
• a plurality of contact structures extending through a second dielectric layer located above the first dielectric layer,
• wherein at least part of the plurality of contact structures are formed of tungsten and each directly contacts either a top surface of a gate electrode of the gate feature or a respective top surface of one of the pair of source/drain features.

A semiconductor device, comprising:

• a first conductive feature disposed over a substrate, wherein the conductive feature is located at least partially in a first dielectric layer;
• a second dielectric layer disposed over the conductive feature and the first dielectric layer;
• a second conductive feature located in the second dielectric layer;
• a third dielectric layer disposed over the second dielectric layer;
• a first tungsten contact extending through the third dielectric layer to contact a top surface of the second conductive feature;
• and
• a second tungsten contact, extending through the third dielectric layer and partially through the second dielectric layer and directly contacting a top surface of the first conductive feature.