Method of forming a planar surface during multi-layer interconnect formation by a laser-assisted dielectric deposition

摘要

A method for depositing a planar dielectric layer between metal traces of a metallization layer of a semiconductor wafer is disclosed. A thin layer of light absorbing material is deposited on the surface of a wafer prior to the formation of metal lines on an overlying patterned metallization layer. A source of directed radiation preferentially heats the light absorbing material while the metal lines reflect the directed radiation and remain largely unheated, thereby allowing dielectric material to be evenly deposited between the metal traces. An isolation layer which insulates the metal traces from the layer of light absorbing material may be required. In some applications, the source of directed radiation is a laser source with a wavelength in the infrared range, and the light absorbing material is a material which absorbs light in this range.