US 4,060,470 AGranted

Sputtering apparatus and method

OwnerPeter J. Clarkeinventor

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Abstract

The sputtering apparatus includes a concentric anode and cathode electrode and a magnetic structure for producing a magnetic field crossed with the electric field (magnetron type discharge) over the cathode region to be sputtered for enhancing the sputtering operation. The magnetic structure includes field shaping means, such as shunts or bucking magnets, to limit the cathode dark space substantially to the effective sputter surface of the cathode. A ground shield surrounding the cathode, but not extending into the dark space, is utilized to contribute to the effect produced by the magnetic field, and means are provided for cooling the anode and cathode. In the case of sputtering ferromagnetic material, a ferromagnetic sputter cathode has its thickness dimensioned so as to be magnetically saturated by the applied magnetic field in a region of relatively low sputter erosion and to be thicker in regions of more intense sputter erosion.

Claims26

Dependent claims

Glow discharge sputtering apparatus for coating a work piece including:

anode and cathode electrode means for operation at independent operating electrical potentials to establish in use a main electric field intercepted by said cathode means;
said cathode electrode means adapted to contain a main portion made of a material to be sputtered from said cathode means onto the work piece;
magnet means including a main magnetic circuit for producing a main magnetic field passing out of and looping back into said main cathode portion and a stray magnetic field not intercepted by said main cathode portion and said main magnetic field being crossed with said electric field over said main cathode portion;
means for applying an operating electrical potential between said anode and cathode means for establishing in operation a main magnetically enhanced glow discharge over said main cathode portion for bombarding said main portion of said cathode means with positive ions to produce sputtering of said cathode material onto the work piece;
and
said magnetic circuit including stray glow discharge suppression means for shaping said stray magnetic field lines in a stray glow discharge region which is otherwise susceptible of supporting a stray glow discharge therein in order to reduce the intensity of said stray glow discharge and stray sputtering generated thereby.

3 more elements

Glow discharge sputtering apparatus for coating a workpiece comprising, a cathode adapted to contain a material to be sputtered, an anode disposed adjacent said said cathode for producing an electric field over a surface of said cathode which is to be sputtered, a first magnetic structure producing a first magnetic field intercepting said cathode and having a substantial component directed orthogonally to the electric field produced between said anode and cathode over the surface of said cathode to be sputtered, second magnetic field means associated with an end region of the first magnetic structure for compressing the end region of the first magnetic field to effectively limit sputtering to the intermediate main area of said cathode, whereby stray sputtering is reduced in use.

Dependencies are inferred from the claim text.