摘要 |
In a dual cathode magnetron, an adjustment circuit is provided between a pair of sputter targets having a coaxial (preferably frusto-conical) relationship to modify the distribution of ion and electron currents flowing from the plasma discharge to a substrate residing within a sputter chamber. A stress adjustment circuit is used to modify the ion bombardment of the growing films on the substrate resulting in a mechanism for control of the stress in the deposited films. In a preferred embodiment, the adjustment circuit comprises a variable resistor disposed between an internal shield that acts as a passive anode and a target. The value of the variable resistor influences the plasma discharge current distribution between the split sputter targets and the internal shields, and can effectively be used to adjust the properties of the deposited films.
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