Fin Field-Effect Transistor Device And Method

A Fin Field-Effect Transistor (FinFET) device comprising:

• a fin protruding above a substrate;
• isolation regions on opposing sides of the fin, the fin protruding above upper surfaces of the isolation regions;
• a capping layer between the fin and the isolations regions, the capping layer contacting sidewalls of the fin;
• a dielectric liner stack between the capping layer and the isolation regions, wherein the dielectric liner stack comprises:
• a first dielectric layer over and extending along the capping layer;
• and
• a second dielectric layer over and extending along the first dielectric layer, the second dielectric layer having a different composition from the first dielectric layer.

A Fin Field-Effect Transistor (FinFET) device comprising:

• a fin over a substrate;
• isolation regions on opposing sides of the fin, wherein an upper portion of the fin protrudes above an upper surface of the isolation regions, wherein a lower portion of the fin is between the upper surface of the isolation region and the substrate;
• a silicon capping layer extending along sidewalls of the lower portion of the fin;
• and
• a dielectric liner stack between the silicon capping layer and the isolation regions, wherein the dielectric liner stack comprises:
• a first dielectric layer over the silicon capping layer;
• and
• a second dielectric layer over the first dielectric layer, the second dielectric layer being an oxide of the first dielectric layer.