Method for forming semiconductor structure

A method for forming a semiconductor structure, comprising:

• forming a gate by a method comprising:
• forming a gate dielectric layer on a substrate;
• forming a gate electrode on the gate dielectric layer;
• forming a nitride spacer on a sidewall of the gate electrode;
• and
• forming a phosphorus containing dielectric layer on the gate, wherein the phosphorus containing dielectric layer has a varied phosphorus dopant density distribution profile, the phosphorus containing dielectric layer comprises a phosphorus dopant density region on an upper surface of the gate and having a triangle-like shape.

A method for forming a semiconductor structure, comprising:

• forming a gate by a method comprising:
• forming a gate dielectric layer on a substrate;
• forming a gate electrode on the gate dielectric layer;
• forming a nitride spacer on a sidewall of the gate electrode;
• forming a phosphorus containing dielectric layer on the gate, wherein the phosphorus containing dielectric layer has a varied phosphorus dopant density distribution profile;
• forming a contact opening in the phosphorus containing dielectric layer by performing an etching step having etch selectivity to the phosphorus containing dielectric layer;
• and
• forming a contact element in the contact opening.