Synthesis of ZrN film via the plasma sputter-type negative ion source
Abstract
Zirconium nitride (ZrN) belongs to the three transition-metal nitride that includes titanium nitride and hafnium nitride, having a NaCl or A15 structure in general, with extreme stability in a generalized sense, that is, hardness, chemical inertness, and high melting point and Young's modulus. These films have been attracting much attention for various application such as Josephson junctions, diffusion barriers, cryogenic thermometers, hard coatings, and others because of their high hardness and corrosion resistance, high thermal and chemical stability, and low resistivity (13.6 μΩ-cm). ZrN films have been prepared on various substrates by several methods including reactive sputtering, dual ion-beam sputtering, chemical vapor deposition, plasma arc, ion plating, and others. The problem with the other deposition methods is the requirement of a high deposition temperature (> 500°C) for the effective formation of the ZrN films. Reference 18 lists the developments in this area worldwide.
In this research, the use of a plasma-sputter-type negative ion source (PSNIS) presents a new approach for the production of ZrN. This technique has some advantages over the conventional methods for ZrN film preparation. Substrate heating would not be necessary and as in the case of TiN deposition, the flux and energy of the ions are controllable depending on the discharge conditions, hence the chemical composition of the film can also be controlled.