Use of modulated inductive power and bias power to reduce overhang and improve bottom coverage

摘要

The present invention provides a method and apparatus for achieving conformal step coverage of one or more materials on a substrate using sputtered ionized material. A plasma is struck and maintained in a processing region by coupling energy into one or more gases. A target disposed in the processing region provides a source of material to be sputtered and then ionized in the plasma environment. During deposition of material onto the substrate, the plasma density is modulated by varying the energy supplied to the plasma. During a period of plasma decay, a bias to a substrate support member is increased to a relatively higher power to periodically enhance the attraction of positively charged particles to the substrate during the afterglow period of the plasma. In one embodiment, a bias to the target is also modulated.