Methods for depositing metal in high aspect ratio features

摘要

Methods for depositing metal in high aspect ratio features formed on a substrate are provided herein. In some embodiments, a method includes applying first RF power at VHF frequency to target comprising metal disposed above substrate to form plasma, applying DC power to target to direct plasma towards target, sputtering metal atoms from target using plasma while maintaining pressure in PVD chamber sufficient to ionize predominant portion of metal atoms, depositing first plurality of metal atoms on bottom surface of opening and on first surface of substrate, applying second RF power to redistribute at least some of first plurality from bottom surface to lower portion of sidewalls of the opening, and depositing second plurality of metal atoms on upper portion of sidewalls by reducing amount of ionized metal atoms in PVD chamber, wherein first and second pluralities form a first layer deposited on substantially all surfaces of opening.

主权项

1. A method of processing a substrate in a physical vapor deposition (PVD) chamber, the substrate having an opening formed in a first surface of the substrate and extending into the substrate towards an opposing second surface of the substrate, the opening having an aspect ratio of height to width of at least 5:1, the method comprising:
applying a first RF power at a VHF frequency to a target comprising a metal disposed above the substrate to form a plasma from a plasma-forming gas; applying DC power to the target to direct the plasma towards the target; sputtering metal atoms from the target using the plasma while maintaining a first pressure in the PVD chamber sufficient to ionize a predominant portion of the metal atoms sputtered from the target; depositing a first plurality of metal atoms on a bottom surface of the opening and on the first surface of the substrate; applying a second RF power to a first electrode disposed beneath the substrate to redistribute at least some of the first plurality of metal atoms from the bottom surface to a lower portion of a sidewall of the opening; and depositing a second plurality of metal atoms on an upper portion of the sidewall by reducing an amount of ionized metal atoms in the PVD chamber, wherein the first and second pluralities of metal atoms form a first layer deposited on substantially all surfaces of the opening.