Replacement gate methods that include treating spacers to widen gate

A device, comprising:

• a first source/drain region and a second source/drain region formed in a substrate;
• a gate structure over the substrate between the first source/drain region and the second source/drain region, wherein the gate structure comprises a gate dielectric layer and a gate electrode over the gate dielectric layer;
• a first spacer contacting a sidewall of the gate structure;
• and
• a second spacer contacting a sidewall of the first spacer, wherein the first spacer is between the second spacer and the gate structure, wherein a first width of the first spacer is greater adjacent the substrate than at a first location more distal from the substrate, wherein a second width of the second spacer is greater adjacent the substrate than at a second location more distal from the substrate.

A device, comprising:

• a first source/drain region and a second source/drain region in a substrate;
• a gate structure over the substrate between the first source/drain region and the second source/drain region, wherein the gate structure comprises a gate dielectric layer and a gate electrode over the gate dielectric layer;
• a first spacer on a sidewall of the gate structure;
• and
• a second spacer on a first sidewall of the first spacer opposite the gate structure, wherein a second sidewall of the first spacer tapers at an angle greater than the first sidewall of the first spacer relative to a line perpendicular to an upper surface of the substrate.