Method for improving the thermal conductivity of metal lines in integrated circuits

Abstract

The method includes forming a metal layer over a substrate. Subsequently, a discrete dot masking is deposited on the surface of the metal layer. A discrete rugged polysilicon or hemispherical grained silicon (HSG-Si) can be chosen as the discrete dot masking. The source gas used to form the discrete rugged polysilicon includes Si2H6 at a temperature of about 400 to 450° C. An anisotropically etching step is performed to etch the metal layer by using the discrete dot masking as an etching mask, thereby forming a surface pattern formed thereon. Then, the discrete dot masking is removed. The metal layer is patterned to a conductive line pattern. An organic material layer with low dielectric constant is formed on the patterned metal layer. A silicon oxide layer is successively formed on the organic material layer, followed by polishing the silicon oxide layer using a chemical mechanical polishing (CMP).

Dependencies are inferred from the claim text.