IR emission from the target during plasma magnetron sputter deposition

Abstract

In this article, energy flux measurements at the substrate location are reported. In particular, the energy flux related to IR radiation emanating from the titanium (10 cm in diam.) target surface is quantified during magnetron sputter deposition processes. In order to modulate the plasma-target surface interaction and the radiative energy flux thereof, the working conditions were varied systematically. The experiments were performed in balanced and unbalanced magnetic field configurations with direct current (DC), pulsed DC and high power impulse magnetron sputtering (HiPIMS) discharges. The power delivered to the plasma was varied too, typically from 100 to 800 W. Our data show that the IR contribution to the total energy flux at the substrate increases with the supplied sputter power and as the discharge is driven in a pulse regime. In the case of HiPIMS discharge generated with a balanced magnetic field, the energy flux associated to the IR radiation produced by the target becomes comparable to the energy flux originating from collisional processes (interaction of plasma particles such as ions, electron, sputtered atoms etc. with the substrate). From IR contribution, it was possible to estimate the rise of the target surface temperature during the sputtering process. Typical values found for a titanium target are in the range 210 °C to 870 °C

Recent Advances in the Development of Nano-Sculpted Films by Magnetron Sputtering for Energy-Related Applications

“…Tilted columnar Ti thin films were synthesized for 373 K < T s < 873 K, where 373 K corresponds to the substrate surface temperature without intentional heating. This value is higher than the ambient temperature because of energy transfer phenomena occurring at the plasma-growing film interface associated with the IR radiation emanating from the Ti target [ 27 ]. The sputtering power was fixed at 150 W while P dep = 0.13 Pa and α = 85°.…”

“…To obtain space-resolved information, electron diffraction during TEM experiments was performed, showing that the films are not homogeneously crystallized: An amorphous phase is deduced at the substrate interface while the anatase phase was detected near the surface region. This late crystallization at the end of the film growth can be explained by a gradual heating of the substrate by ions bombardment, surface reactions, and intense IR radiation emanating from the target [ 27 ].…”

“…However, the morphology of the films depends on the different deposition parameters [ 44 , 45 , 46 , 47 ]. Consequently, to simulate the growth of thin films synthesized at high temperature or with high-kinetic-energy incoming atoms, the approximation of ballistic deposition has to be completed by the diffusion phenomenon [ 22 , 27 ]. Diffusion and evaporation events can take place between two atom depositions at an equal time interval determined by the deposition rate.…”

“…By contrast, as mentioned, magnetron sputtering is a recognizable technique to do this even without intentional heating of the growing material. Indeed, in this case, the crystallization is promoted by the bombardment of energetic particles, as well as infrared radiation emitted from the target during the sputtering process [ 27 ]. Although promising, the utilization of GLAD geometry in combination with magnetron sputtering, i.e.…”

Ultraviolet/vacuum-ultraviolet emission from a high power magnetron sputtering plasma with an aluminum target

“…However, ionic and neutral fluxes not only determine the properties of the deposited film (substrate). The infrared (IR) radiation emitted by the target (cathode) is also contributing to the total energy delivered to the deposited film during the growth, as shown by Cormier et al [10]. The contribution of IR is largest -up to 600 mW • cm -when the magnetic field configuration of the magnetron is balanced.…”