Method of forming gate structure with undercut region and resulting device

A device, comprising:

• a plurality of fins positioned above a first region of a substrate;
• an isolation structure positioned above a second region of the substrate, wherein the isolation structure is not positioned above the plurality of fins;
• and
• a gate structure positioned above the plurality of fins and above the isolation structure, wherein a first portion of the gate structure positioned above the isolation structure has a first vertical thickness and a second portion of the gate structure positioned between the plurality of fins has a second vertical thickness, wherein the first vertical thickness is less than the second vertical thickness and wherein, when viewed in a cross-section taken through the first portion of the gate structure in a direction corresponding to a gate width direction of the device, the isolation structure comprises a generally U-shaped insulating liner and a dielectric material positioned within the generally U-shaped insulating liner.

A device, comprising:

• a plurality of fins positioned above a first region of a substrate;
• an isolation structure positioned above a second region of the substrate, wherein the isolation structure is not positioned above the plurality of fins;
• and
• a gate structure positioned above the plurality of fins and above the isolation structure, wherein a lowermost surface of a first portion of the gate structure positioned above the isolation structure is positioned at a level that is above a level of an uppermost surface of at least one of the plurality of fins and wherein, when viewed in a cross-section taken through the first portion of the gate structure in a direction corresponding to a gate length direction of the device, the device further comprises a generally U-shaped insulating spacer that is positioned adjacent a bottom surface and opposing side surfaces of the first portion of the gate structure.

A device, comprising:

• a plurality of fins positioned above a first region of a substrate;
• an isolation structure positioned above a second region of the substrate, wherein the isolation structure is not positioned above the plurality of fins;
• a gate structure positioned above the plurality of fins and above the isolation structure, wherein a first portion of the gate structure positioned above the isolation structure has a first vertical thickness and a second portion of the gate structure positioned between the plurality of fins has a second vertical thickness, wherein the first vertical thickness is less than the second vertical thickness;
• and
• a generally U-shaped insulating spacer wherein, when viewed in a cross-section taken through the first portion of the gate structure in a direction corresponding to a gate length direction of the device, the generally U-shaped insulating spacer is positioned adjacent a bottom surface and opposing side surfaces of the first portion of the gate structure and wherein, when viewed in a cross-section taken through the first portion of the gate structure in a direction corresponding to a gate width direction of the device, the isolation structure comprises a generally U-shaped insulating liner and a dielectric material positioned within the generally U-shaped insulating liner.