METHOD AND APPARATUS FOR THIN FILM ALUMINUM PLANARIZATION

摘要

In a first aspect of the present invention, a method of aluminum deposition and planarization effective for filling of structures with high aspect ratios (5:1 or greater) comprises the steps of: a) cooling the wafer during the deposition of a Ti-containing wetting layer so that wafer temperatures during and after deposition are held within a range of about -20 DEG to 85 DEG C; b) depositing a first layer of aluminum of thickness of about 2500 ANGSTROM to about 5000 ANGSTROM in a period of about 240 to about 300 seconds using a low input power level to a low pressure argon plasma of approximately 1 to 2 kW at an argon pressure of about 0.65 mT to about 1.5 mT; and c) depositing a second aluminum layer in a period of about 20 seconds to about 30 seconds using a higher input power level to a low pressure argon plasma of approximately 20 kW at an argon pressure of about 0.65 mT to about 1.5 mT. A clampless chuck is preferably utilized to provide infrared heating of the wafer during the second aluminum layer deposition step.