Shaped field magnetron electrode

Claim 1

A plasma processing equipment including an evacuable chamber; means for evacuating the chamber; means for introducing a preselected reactant gas into the chamber; a cathode mounted in an upper part of the chamber and having a downward-facing sputtering surface; an electrode disposed beneath the cathode for supporting a substrate, the electrode comprising: a body having substantially the shape of a rectangular parallelepiped with mutually orthogonal length, width, and thickness dimensions, the thickness of the body being substantially less than the length and width of the body, the length and width dimensions defining a horizontal upward-facing substrate support face and an obverse face, the length and thickness dimensions defining opposite side edges, and the width and thickness dimensions defining opposite ends of the body, and two magnetic members, each disposed at a respective end of the electrode body, one of the magnetic members constituting a first magnetic pole of one polarity and the other magnetic member constituting a second magnetic pole of opposite polarity, so that a magnetic field extends between the magnetic members adjacent to the faces and side edges in a continuous belt surrounding the body; and a power supply connected to the sputtering cathode and the substrate support electrode for delivering electrical energy to the sputtering cathode at a first predetermined voltage appropriate for causing sputtering from said sputtering surface and for delivering electrical energy to the substrate support electrode at a second predetermined voltage appropriate for causing ionization of the reactant gas adjacent to the substrate support surface without causing significant sputtering from a substrate on said support surface.