Process and apparatus for cold copper deposition to enhance copper plating fill

摘要

A process and apparatus for depositing thin films onto a substrate. The process comprises mounting a wafer onto a wafer chuck and pumping a cryogenic fluid through the chuck which cools the wafer chuck and the wafer to a temperature below about +20° C. A thin film is then deposited over the cooled wafer using a sputter deposition process while maintaining the temperature of the wafer chuck and the wafer below about +20° C. The preferred embodiment of the present invention includes the use of liquid nitrogen as the cryogenic fluid, and copper as the material to be deposited through the sputtering process. In addition, the preferred embodiment cools the wafer chuck and the wafer to a temperature of about −100° C. The apparatus includes the physical vapor deposition vessel, the wafer chuck, the source of material to be deposited, the wafer, and the cooling line which passes through the wafer chuck to carry the cooling fluid to the chuck.