Buried Metal for FinFET Device and Method

A method comprising:

• forming a first recess in a substrate and a second recess in the substrate, the second recess separated from the first recess;
• forming a first buried metal line in the first recess and a second buried metal line in the second recess;
• forming a first dielectric material over the first buried metal line;
• forming a second dielectric material over the second buried metal line;
• forming a first plurality of semiconductor fins adjacent the first buried metal line;
• forming a second plurality of semiconductor fins adjacent the second buried metal line;
• selectively etching a portion of the first dielectric material to expose a portion of the first buried metal line;
• selectively etching a portion of the second dielectric material to expose a portion of the second buried metal line;
• forming a first dummy gate structure over the first plurality of semiconductor fins and the exposed portion of the first buried metal line;
• forming a second dummy gate structure over the second plurality of semiconductor fins and the exposed portion of the second buried metal line;
• replacing the first dummy gate structure with a first metal gate structure;
• and
• replacing the second dummy gate structure with a second metal gate structure.

A semiconductor device comprising:

• a buried metal line disposed in a semiconductor substrate;
• a first dielectric material on a first sidewall of the buried metal line and a second dielectric material on a second sidewall of the buried metal line;
• a first plurality of fins disposed proximate the first sidewall of the buried metal line;
• a second plurality of fins disposed proximate the second sidewall of the buried metal line;
• a first metal gate structure over the first plurality of fins and over the buried metal line, wherein the first metal gate structure extends through the first dielectric material to contact the buried metal line;
• and
• a second metal gate structure over the second plurality of fins and over the buried metal line.