Self-ionized and capacitively-coupled plasma for sputtering and resputtering

摘要

A DC magnetron sputter reactor for sputtering deposition materials such as tantalum and tantalum nitride, for example, and its method of use, in which self-ionized plasma (SIP) sputtering and capacitively coupled plasma (CCP) sputtering are promoted, either together or alternately, in the same chamber. Also, bottom coverage may be thinned or eliminated by inductively-coupled plasma (ICP) resputtering. SIP is promoted by a small magnetron having poles of unequal magnetic strength and a high power applied to the target during sputtering. CCP is provided by a pedestal electrode which capacitively couples RF energy into a plasma. The CCP plasma is preferably enhanced by a magnetic field generated by electromagnetic coils surrounding the pedestal which act to confine the CCP plasma and increase its density.

主权项

1. A reactor system for depositing conductive material onto a substrate, comprising:
target means including a target, for sputter depositing a layer of conductive material onto said substrate, and for generating a self ionized plasma to ionize a portion of said conductive material sputtered from said target means prior to being deposited onto said substrate; capacitively coupled plasma means including a pedestal having a pedestal electrode, for generating a capacitively coupled plasma, and for biasing a substrate to attract plasma ions to resputter a portion of said conductive material from said substrate; and electromagnetic coil means, including a first electromagnetic coil and a second electromagnetic coil, each coil having turns wound around the periphery of the pedestal and surrounding an area between the target and the pedestal, for generating a magnetic field to surround said pedestal and confine said capacitively coupled plasma in the area between the target and the pedestal to increase the density of said capacitively coupled plasma adjacent said pedestal electrode wherein said electromagnetic coil means further includes selectable source means for driving currents through said first and second electromagnetic coils separately so that the levels and polarities of the currents through the first and second electromagnetic coil may be separately selected.