High purity RF-sputter type metal ion source for non-mass-separated ion beam deposition

High purity RF-sputter type metal ion source has been developed for non-mass separated ion beam deposition. Fe or Cu rod target of purity 99.999 % or 99.9999 %, respectively, was DC-sputtered inside an RF inductively generated Ar plasma. optical emission spectroscopy from the plasma region (Fe case) indicated that emission from Fe* becomes larger than that of Ar* when DC bias voltage of - 1 kV was applied. This result agreed with our previous mass spectroscopic that Fe+ ion intensity overcomes that of Ar+ because of an efficient Penning ionization of sputtered and evaporated Fe particles. Cu films deposited on Si substrate at RT with the ion source showed non-columnar structure at it substrate bias voltage of - 150 V, whereas only columnar structure was obtained with no bias voltage. This tendency qualitatively agreed with the case of Fe film formation obtained in our mass separated IBD.