Method and apparatus for providing modulated bias power to a plasma etch reactor
AssigneeApplied Materials, Inc.
InventorsElisabeth Weikmann, Aduato Diaz JR., Sharma V. Pamarthy, Ajay Kumar, Padmapani C. Nallan
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Abstract
A method and apparatus for modulating the bias power applied to a wafer support pedestal within a plasma etch reactor. The modulation has an on/off duty cycle of between 10 and 90 percent. Such modulation of the bias power substantially improves the verticality of the etched features located near the edge of a semiconductor wafer as the wafer is being etched in a plasma etch reactor.
Claims23
A method of etching a wafer in a plasma etch reactor, where the wafer is supported in a volume within the plasma etch reactor upon a wafer support pedestal, the method comprising:
- supplying a reactive gas to the volume;
- generating a plasma within the volume;
- and
- applying modulated bias power to the wafer support pedestal.
Apparatus for etching a wafer comprising:
- a plasma etch reactor comprising a volume and a wafer support pedestal that supports the wafer in said volume;
- a gas source for supplying a reactive gas to the volume;
- a source power supply for applying energy to the reactive gas and forming a plasma in the volume;
- and
- a bias power supply, coupled to the wafer support pedestal, for supplying a modulated bias power.
Dependencies are inferred from the claim text.