Thin-Film Deposition With Refractory Materials Using a Vacuum Arc

Refractory metal plasma generated by a vacuum arc was used to deposit thin films with different arc currents I. The deposition rate Vdep was measured for electrode configurations including a planar Zr cathode and a planar W anode; cylindrical W or Mo electrode pairs and a cylindrical Nb cathode closed by a BN plate and a W or Nb shower-head cup anode or with one-hole Ta cup anode. Vdep for a Mo electrode pair with I = 275 A at a distance L = 110 mm from the electrode axis reached 2.2 μm/min, 60 s after arc ignition. For the W electrode pair Vdep was ~1 μm/min at 80 s (I = 200 A and L = 110 mm), while for W film deposition with shower-head anode Vdep was ~0.6 μm/min (I = 200 A and L = 60 mm). For Nb films deposited with the closed electrode configuration, Vdep was 0.3 μm/min at 30 s after arc ignition (I = 275 A and L = 80 mm from the anode front).

I. Introduction

Plasma deposition of metallic films is of interest in optics, microelectronics, and nanostructure formation [1]. Among the various plasma techniques, cathodic arc deposition is interesting because of its plasma properties [2]: the plasma is in the form of a jet with highly energetic multiply charged ions. The energetic depositing ions produce dense and adherent films and coatings.