Dual stress liners for integrated circuits

A method of fabricating an integrated circuit comprising:

• providing a substrate with first and second active regions defined thereon with first and second transistors, the first transistor comprises a first type and the second transistor comprises a second type, and an isolation region between the first and second active regions;
• forming a first stress layer on the substrate to cover the first transistor, the first stress layer produces a first stress for enhancing mobility of a second charge carrier type;
• forming a second stress layer on the substrate, the second stress layer produces a second stress to enhance mobility of a first charge carrier type, wherein the second stress layer overlaps the first stress layer in the isolation region;
• and
• polishing the substrate to remove a portion of the second stress layer that overlaps the first stress layer to produce an interface between the first and second stress layers having a coplanar upper surface without a gap.

A method of fabricating an integrated circuit comprising:

• providing a substrate with first and second active regions defined thereon with first and second transistors, the first transistor comprises a first type and the second transistor comprises a second type;
• forming a first stress layer on the substrate which covers the first and second transistors, the first stress layer produces a first stress;
• patterning the first stress layer to remove portions of the first stress layer over the second active region;
• forming a second stress layer on the substrate, the second stress layer produces a second stress;
• patterning the second stress layer to remove portions of the second stress layer over the first active region, the patterning creates an overlap of the second stress layer over the first stress layer in a region between the active regions to avoid gaps between the first and second stress layers;
• and
• polishing the substrate to produce an interface between the first and second stress layers having a coplanar upper surface without a gap.