Patent ID: 8431485

Claim:
A manufacturing method for a buried circuit structure comprising: providing a substrate having at least a trench formed therein; forming a first conductive layer on the substrate blanketly so that the first conductive layer covers a surface of the substrate, sidewalls of the trench, and a bottom of the trench; forming a patterned photoresist in the trench, the patterned photoresist having a top surface lower than an opening of the trench; removing the first conductive layer not covered by the patterned photoresist to form a second conductive layer having a top lower than an opening of the trench in the trench; removing the patterned photoresist; performing a dry etching process to remove the second conductive layer from the bottom of the trench to form a third conductive layer on the sidewalls of the trench; performing a selective metal chemical vapor deposition to form a metal layer having a top lower than the surface of the substrate; and forming a protecting layer filling the trench on the metal layer.