Magnetic control of film deposition

Claim 1

IN A METHOD OF COATING AN ARTICLE BY SPUTTERING INCLUDING ARRANGING SAID ARTICLE WITHIN A CLOSED VESSEL HAVING A CATHODE AND AN ANODE AND IMPOSING WITHIN SAID VESSEL A SUITABLE PRESSURE OF IONIZABLE GAS AND A SUITABLE ANODECATHODE VOLTAGE POTENTIAL DIFFERENCE TO THEREBY OBTAIN ABNORMAL GLOW DISCHARGE CONDITIONS THEREIIN, SAID DISCHARGE COMPRISING ELECTRON-COLLISION IONIZATION OF SAID IONIZABLE GAS AND, IN TURN, ION-BOMBARDMENT AND IMPACT-EROSION OF A SURFACE OF SAID CATHODE, AS WELL AS SECONDARY ELECTRON EMISSION AT SAID CATHODE, SAID DISCHARGE THEREBY OCCURING ABOUT AN AXIS CENTURALLY LOCATED AND PERPENDICULAR TO SAID SURFACE OF SAID CATHODE, THE IMPROVEMENT COMPRISING THE STEPS OF: SUPERPOSING A MAGNETIC FIELD HAVING A MAJOR TRANSVERSE COMPONENT SUBSTANTIALLY PERPENDICULAR TO SAID DISCHARGE AXIS AND RADIALLY SYMMETRIC THEREABOUT; LOCATING SAID MAJOR TRANSVERSE COMPONENT OF SAID FIELD AT A POINT ALONG SAID AXIS BETWEEN SAID CATHODE AND SAID ANODE WITHIN 60 MM. FROM SAID SURFACE OF SAID CATHODE TO THEREBY INCREASE THE MEANS FREE PATH OF SAID ELECTRONS; AND POSITIONING SAID ARTICLE IN THE NEGATIVE GLOW REGION OF SAID DISCHARGE AND WITHIN THE BOUNDS FORMED BY SAID SURFACE OF SAID CATHODE, SAID BOUNDS BEING VIEWED THROUGH FORMING A CYLINDRICAL SURFACE EXTENDING PARALLEL TO SAID AXIS, TO THEREBY PROVIDE UNIFORM DEPOSITION THEREON.