Abstract
Inductively coupled impulse sputtering (ICIS) is a new development in the field of highly ionised pulsed PVD processes. For ICIS the plasma is generated by an internal inductive coil, replacing the need for a magnetron. To understand the plasma properties, measurements of the current and voltage waveforms at the cathode were conducted. The ion energy distribution functions (IEDFs) were measured by energy resolved MS and plasma chemistry was analysed by OES and then compared to a model. The target was operated in pulsed DC mode and the coil was energised by pulsed RF power, with a duty cycle of 7.5%. At a constant pressure (14 Pa) the set peak RF power was varied from 1000–4000 W. The DC voltage to the target was kept constant at 1900 V. OES measurements have shown a monotonic increase in intensity with increasing power. Excitation and ionisation processes were single step for ICIS of Ti and Ni and multi-step for Cu. The latter exhibited an unexpectedly steep rise in ionisation efficiency with power. The IEDFs measured by MS show the material- and time-dependant plasma potential in the range of 10–30 eV, ideal for increased surface mobility without inducing lattice defects. A lower intensity peak, of high energetic ions, is visible at 170 eV during the pulse.
Highlights
Ionised plasma processes have helped to improve coating properties by enabling the control of the flux of ionised sputtered species, initially with an ancillary ionisation source such as inductively coupled plasma and magnetron sputtering (ICP-MS) [1] and more recently by utilising a higher pulsed power applied directly to a magnetron cathode such as high power impulse magnetron sputtering (HIPIMS) [2].Deposition of magnetic materials, such as nickel, is problematic with magnetron sputtering as the magnetic confinement field that enhances the sputter process is reduced due to quenching of the magnetic flux density by the target material [3]
Analysis of the optical emission of the Inductively coupled impulse sputtering (ICIS) discharge was conducted by recording spectra by an OES monochromator (Jobin Yvon Triax 320, HORIBA Synapse CCD detector) with a spectral resolution of 0.12 nm
Conducting large RF currents in the coil creates a magnetic field perpendicular to the target surface, which counteracts the weakening of plasma confinement normally associated with the quenching of the magnetic field by the magnetic target materials in conventional ionised PVD (I-PVD) magnetron processes
Summary
Ionised plasma processes have helped to improve coating properties by enabling the control of the flux of ionised sputtered species, initially with an ancillary ionisation source such as inductively coupled plasma and magnetron sputtering (ICP-MS) [1] and more recently by utilising a higher pulsed power applied directly to a magnetron cathode such as high power impulse magnetron sputtering (HIPIMS) [2]. The sputtered material is ionised as it passes through the coil volume, creating a highly ionised metal flux to the substrate. This high ionisation degree allows the coating of structured surfaces with high aspect ratios with a reduced lattice defect density [13, 14]. Nickel is especially of interest as it is a pure ferromagnetic material
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
