Discharge characteristics of electronegative Mg–CF4 direct current magnetron sputtering by probe measurements

Journal of Applied Physics

Published On 2021/6/21

The discharge characteristics of Mg–CF 4 direct current (DC) reactive magnetron sputtering, which is assumed to be a typical electronegative discharge, are investigated as a function of CF 4/(Ar+ CF 4) discharge gas ratios using probe measurements. For comparison, the discharge characteristics of Mg–CF 4 radio frequency (RF) magnetron sputtering are also investigated. The results of the probe measurements show that the plasma potentials (V plasma) of Mg–CF 4 DC discharges decrease with increasing CF 4/(Ar+ CF 4) ratios and become negative relative to the ground potential for discharges with CF 4/(Ar+ CF 4) ratios of≥ 60% for all discharge pressures investigated (0.40, 1.20, and 2.00 Pa). In contrast, the V plasma of Mg–CF 4 RF discharges remains 30–40 V higher than the ground potential independent of the CF 4/(Ar+ CF 4) ratio. The electron temperature obtained from the logarithmic plot of the probe …

Journal

Journal of Applied Physics

Published On

2021/6/21

Volume

129

Issue

23

Authors

Eiji Kusano

Eiji Kusano

Kanazawa Institute of Technology

Position

H-Index(all)

24

H-Index(since 2020)

9

I-10 Index(all)

0

I-10 Index(since 2020)

0

Citation(all)

0

Citation(since 2020)

0

Cited By

0

Research Interests

Sputtering

Thin Film Physics

Materials Science

University Profile Page

Other Articles from authors

Eiji Kusano

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Revisitation of reactive direct current magnetron sputtering discharge: Investigation of Mg–CF4, Mg–O2, and Ti–O2 discharges by probe measurements

The reactive direct current (DC) magnetron sputtering discharges of Mg-CF4, Mg-O2, and Ti-O2 were investigated using probe measurements as a function of reactive gas flow ratio. The emission spectroscopy, which was conducted before the probe measurements, demonstrates that all the three DC discharges transit from nonreactive to reactive discharge mode with increasing reactive gas flow ratio. The probe measurements show that the plasma potentials of the Mg-O2 and Ti-O2 DC discharges slightly increase or remain almost constant with increasing reactive gas flow ratio, whereas that of the Mg-CF4 DC discharge drastically decreases at the mode transition. For the same change in reactive gas flow ratio, the discharge voltage of the Mg-CF4 DC discharge slightly increases and that of the Mg-O2 DC discharge drastically increases at the mode transition, whereas that of the Ti-O2 DC discharge slightly …

Eiji Kusano

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Dependence of film structure on the film structure-independent equivalent film thickness in magnetron sputtering deposition of Ag thin films

In this work, I have investigated the structures and properties of Ag thin films deposited by magnetron sputtering onto glass substrates with temperatures of 150 and 600 C for film structure-independent equivalent film thicknesses in the range of 20–400 nm. The Ag thin film morphologies observed using scanning electron microscopy and atomic force microscopy showed the following distinguishable changes: an Ag thin film with an equivalent film thickness of 20 nm deposited at a substrate temperature of 150 C displayed a film microstructure of oblate grains separated by voids, while those with equivalent film thicknesses of 50 nm or more displayed microstructures consisting of flat-topped grains without any obvious voids between them. In comparison, an Ag thin film with an equivalent film thickness of 20 nm deposited at a substrate temperature of 600 C displayed a microstructure consisting of isolated spherically …

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Growth of flat-topped, mound-shaped grains with voids when depositing silver thin films at high substrate temperatures using direct-current magnetron sputtering

Thin films of silver were deposited on nonalkali glass substrates at substrate temperatures ranging from room temperature (28 C) to 150, 200, 300, 400, and 500 C at discharge pressures of 0.40, 1.20, and 2.00 Pa using direct current magnetron sputtering. On the basis of the measured cross-sectional and surface morphologies, crystallographic structures, and film properties, I discuss the dependence of the film structure and properties on the substrate temperature. The x-ray diffraction measurements showed that the< 111> orientation was preferred for all deposition conditions. Scanning electron microscope observations revealed a microstructure of convex-shaped fine grains for a substrate at room temperature, while laterally growing, mound-shaped grains with flat-topped surfaces appeared at substrate temperatures of 400 and 500 C. Atomic force microscopy also showed an increase in the lateral size and height …

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