HIGHLY IONIZED PVD WITH MOVING MAGNETIC FIELD ENVELOPE FOR UNIFORM COVERAGE OF STRUCTURE AND WAFER

摘要

This invention relates to ionized PVD processing of semiconductor wafers and provides conditions for highly uniform deposition-etch process sequence and coverage capabilities of high aspect ratio (HAR) features within a single processing chamber. A plasma is generated and maintained by an inductively coupled plasma (ICP) source (15). A deposition process step is performed in which metal vapor is produced from a target (25) of a PVD source (20). Location and sputter efficiency at the target surface is enhanced by moving a magnet (34) pack to create a traveling or sweeping magnetic field envelope. The target is energized from a DC power supply and pressures effective for an efficient thermalization of the sputtered atoms (30 < p < 100 mTorr) are maintained in the chamber during deposition. A uniform thickness of the metal on the wafer is produced within each magnet sweeping cycle. Magnetic field localization using an annular sweeping motion over the entire target surface generates conditions for reasonable deposition rates, high target utilization, high ionization of the metal atoms, uniform flat field deposition and etching, and nearly identical conditions for HAR feature coverage at the center and edge of the wafer.