Semiconductor device and formation thereof

A semiconductor device comprising:

• a gate structure comprising:
• a gate dielectric, a gate dielectric bottom surface of the gate dielectric lying within a first plane;
• and
• a gate electrode over the gate dielectric;
• a first sidewall spacer adjacent a first side of the gate structure, wherein:
• a first sidewall spacer bottom surface of the first sidewall spacer lies within a second plane different than the first plane;
• and
• the first sidewall spacer bottom surface abuts the gate dielectric;
• and
• an active area comprising:
• a first active area layer having a first dopant concentration;
• a second active area layer having a second dopant concentration, the second active area layer over the first active area layer;
• and
• a third active area layer having a third dopant concentration, the third active area layer over the second active area layer and extending above a top surface of a substrate within which the first active area layer and the second active area layer are formed, where the first dopant concentration is less than the second dopant concentration, and the second dopant concentration is less than the third dopant concentration.

A semiconductor device comprising:

• a gate structure comprising:
• a gate dielectric having a bottom surface that interfaces an underlying substrate at an interface lying within a first plane;
• and
• a gate electrode over the gate dielectric;
• and
• a first sidewall spacer in contact with the gate electrode and having a bottom surface lying within a second plane intersecting the first plane, wherein the second plane intersects the first plane at a location where the bottom surface of the first sidewall spacer abuts a first side of the gate dielectric;
• and
• an active area comprising:
• a first active area layer vertically co-planar with the gate dielectric and having a first dopant concentration;
• a second active area layer above the first active area layer and having a second dopant concentration different than the first dopant concentration;
• and
• a third active area layer above the second active area layer, the third active area layer having a third dopant concentration different than the second dopant concentration and different than the first dopant concentration.