• 한국표면공학회지
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• 제29권2호
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• pp.93-99
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• 1996

In this work BN thin films were deposited on Si substrate by R. F. sputtering method at $200^{\circ}C$ and in Ar + $N_2$ mixed gas atmosphere. In order to investigate the effect of ion bombardment on substrate for c-BN bonding, substrate bias voltage was applied. The optimum substrate bias voltage for c-BN bonding was determined by FTIR analysis on specimens which were deposited with various bias voltages. Then BN thin film was deposited with this optimum condition and its phase, morphology, chemical composition, and refractive index were compared with those of BN film which was deposited without bias voltage. FTIR results showed that BN films deposited with substrate bias voltage were composed of mixed phases of c-BN and h-BN, while those deposited without bias voltage were h-BN only. When pure Ar gas was used for sputtering gas, BN films were delaminated easily from substrate in air, while when 10% $N_2$ gas was added to the sputtering gas, although c-BN specific infrared peak was reduced, delamination did not occur. GXRD and TEM results showed that BN films were amorphous phases regardless of substrate bias voltage, and AES results showed that the chemical compositions of B/N were about 1.7~1.8. The refractive index of BN film deposited with bias voltage was higher than that without bias voltage. The reason is believed to be the existence of c-BN bonding in BN film and the higher density of film that deposited with the substrate bias voltage.

• Transactions on Electrical and Electronic Materials
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• 제5권4호
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• pp.153-157
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• 2004

ITO thin films were deposited on PET and soda-lime glass substrates by a dc reactive magnetron sputtering of In-Sn alloy metal target without substrate heater and post-deposition thermal treatment. The dependency of rf-bias voltage and substrate power during deposition processing was investigated to control the electrical and optical properties of ITO films. The range of rf bias voltage is from 0 to -80 V and the substrate power is applied from 10 to 50 W. The minimum resistivity of ITO film is 5.4${\times}$10$^{-4}$ $\Omega$cm at 50 W power and rf-bias voltage of -20 V. The best transmittance of ITO films at 550 nm wavelength is 91 % in the substrate power of 30 W and rf-bias voltage of -80 V.

• 한국진공학회지
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• 제12권3호
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• pp.174-181
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• 2003

본 논문은 탄탈 확산 방지막의 증착시 음의 기판 바이어스에 의한 탄탈막의 특성변화와 열적 안정성에 대해서 고찰하였다. 기판 바이어스를 걸지 않은 경우, 탄탈막은 원주형 모양의 결정 성장을 보이는 주상구조와 250 $\mu\Omega$cm의 높은 비저항값을 보였으나, 기판 바이어스를 걸어줌에 파라서 주상구조가 아닌 치밀한 미세구조와 표면이 평탄한 막이 형성되었고 비저항값도 현저히 감소되었으며, 특히 -125 V에서 증착된 탄탈막은 비저항값이 약 40 $\mu\Omega$cm로 이는 탄탈 벌크의 저항값 (13 $\mu\Omega$cm)에 근접한 값임을 알 수 있었다. 또한, 탄탈 확산 방지막의 열적 안정성에 대해서도, 기판 바이어스를 걸지 않은 탄탈막의 경우 $400^{\circ}C$에서 구리와 실리콘의 반응에 의해 비저항 값이 크게 증가한 결과에 비해, 기판 바이어스에 의해 증착된 탄탈막의 경우 $600^{\circ}C$까지 확산 방지막의 효과를 유지하고 있는 것으로 관찰되었다.

• Transactions on Electrical and Electronic Materials
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• 제12권5호
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• pp.209-212
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• 2011

Hafnium nitride (HfN) thin films were deposited onto a silicon substrate by inductive coupled nitrogen plasma-assisted radio frequency magnetron sputtering. The films were prepared without intentional substrate heating and a substrate negative bias voltage ($-V_b$) was varied from -50 to -150 V to accelerate the effects of nitrogen ions ($N^+$) on the substrate. X-ray diffractometer patterns showed that the structure of the films was strongly affected by the negative substrate bias voltage, and thin film crystallization in the HfN (100) plane was observed under deposition conditions of -100 $V_b$ (bias voltage). Atomic force microscopy results showed that surface roughness also varied significantly with substrate bias voltage. Films deposited under conditions of -150 $V_b$ (bias voltage) exhibited higher hardness than other films.

• 한국세라믹학회지
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• 제47권6호
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• pp.479-484
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• 2010

Microstructural and mechanical properties of the TiN films deposited on Si substrates under various substrate bias voltages by a reactive magnetron sputtering have been studied. It was found that the crystallographic texture, microstructural morphology and mechanical property of the TiN films were strongly depended on the substrate bias voltage. TiN films deposited without bias exhibited a mixed (200)-(111) texture with a strong (200) texture, which subsequently changed to a strong (111) texture with increasing bias voltage. It is also observed that the crystallite size decreases with increasing bias voltage, which corresponds to the increasing diffraction peak width of XRD patterns. The average surface roughness was calculated from AFM images of the films; these results indicated that the average surface roughness was increased with an increase in the bias voltage of the coatings.

• 한국재료학회지
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• 제33권9호
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• pp.372-376
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• 2023

Transparent conductive tungsten (W) doped indium oxide (In₂O₃; IWO) films were deposited at different substrate bias voltage (-V_b) conditions at room temperature on glass substrates by radio frequency (RF) magnetron sputtering and the influence of the substrate bias voltage on the optical and electrical properties was investigated. As the substrate bias voltage increased to -350 V_b, the IWO films showed a lower resistivity of 2.06 × 10^-4 Ωcm. The lowest resistivity observed for the film deposited at -350 V_b could be attributed to its higher mobility, of 31.8 cm²/Vs compared with that (6.2 cm²/Vs) of the films deposited without a substrate bias voltage (0 V_b). The highest visible transmittance of 84.1 % was also observed for the films deposited at the -350 V_b condition. The X-ray diffraction observation indicated the IWO films deposited without substrate bias voltage were amorphous phase without any diffraction peaks, while the films deposited with bias voltage were polycrystalline with a low In₂O₃ (222) diffraction peak and relatively high intensity (431) and (046) diffraction peaks. From the observed visible transmittance and electrical properties, it is concluded that the opto-electrical performance of the polycrystalline IWO film deposited by RF magnetron sputtering can be enhanced with effective substrate bias voltage conditions.

• 한국표면공학회지
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• 제52권6호
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• pp.342-349
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• 2019

Titanium nitride(TiN) thin films have been deposited on PEN(Polyethylene naphthalate) substrate by reactive RF(13.56 MHz) magnetron sputtering in a 25% N₂/Ar mixed gas atmosphere. The pulsed DC bias voltage of -50V on substrates was applied with a frequency of 350 kHz, and duty ratio of 40%(1.1 ㎲). The effects of pulsed DC substrate bias voltage on the crystallinity, color, electrical properties of TiN_x films have been investigated using XRD, SEM, XPS and measurement of the electrical properties such as electrical conductivity, carrier concentration, mobility. The deposition rates of TiN_x films was decreased with application of the pulsed DC substrate bias voltage. The TiN_x films deposited without and with pulsed bias of -50V to substrate exhibits gray and gold colors, respectively. XPS depth profiling revealed that the introduction of the substrate bias voltage resulted in decreasing oxygen concentration in TiN_x films, and increasing the electrical conductivities, carrier concentration, and mobility to about 10 times, 5 times, and 2 times degree, respectively.

• 한국재료학회지
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• 제17권11호
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• pp.618-621
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• 2007

Chromium nitride (CrN) films were deposited on silicon substrate by RF magnetron sputtering assisted by inductive coupled nitrogen plasma without intentional substrate heating. Films were deposited with different levels of bombarding energy by nitrogen ions $(N^+)$ to investigate the influence of substrate bias voltage $(V_b)$ on the growth of CrN thin films. XRD spectra showed that the crystallographic structure of CrN films was strongly affected by substrate bias voltage. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) results showed that surface roughness and grain size of the CrN films varied significantly with bias voltage. For - 80 $V_b$ depositions, the CrN films showed bigger grain sizes than those of other bias voltage conditions. The lowest surface roughness of 0.15 nm was obtained from the CrN films deposited at .130 $V_b$.

• 한국표면공학회지
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• 제54권3호
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• pp.133-138
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• 2021

Ternary Ti-X-N coatings, where X = Al, Si, Cr, O, etc., have been widely used for machining tools and cutting tools such as inserts, end-mills, and etc. Ti-Al-N-O coatings were deposited onto silicon wafer and WC-Co substrates by a cathodic arc evaporation (CAE) technique at various negative substrate bias voltages. In this study, the influence of substrate bias voltages during deposition on the microstructure and mechanical properties of Ti-Al-N-O coatings were systematically investigated to optimize the CAE deposition condition. Based on results from various analyses, the Ti-Al-N-O coatings prepared at substrate bias voltage of -80 V in the process exhibited excellent mechanical properties with a higher compressive residual stress. The Ti-Al-N-O (-80 V) coating exhibited the highest hardness around 30 GPa and elastic modulus around 303 GPa. The improvement of mechanical properties with optimized bias voltage of -80 V can be explained with the diminution of macroparticles, film densification and residual stress induced by ion bombardment effect. However, the increasing bias voltage above -80 V caused reduction in film deposition rate in the Ti-Al-N-O coatings due to re-sputtering and ion bombardment phenomenon.

• 한국진공학회지
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• 제14권1호
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• pp.17-23
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• 2005

본 논문은 글로우방전 질량분석법(Glow Discharge Mass Spectrometry: GDMS)을 이용하여 구리 박막내의 미량 불순물의 농도분석과 음의 기판 바이어스에 대한 구리 박막내의 불순물의 농도변화에 대해서 고찰하였다. 구리 박막은 실리콘 기판 위에 비질량 분리형 이온빔 증착장비를 이용하여 기판 바이어스를 걸지 않은 경우와 -50 V의 기판 바이어스를 걸은 상태에서 증착하였다. 전기를 통하지 않는 분석 샘플의 경우, 직류(DC) GDMS에 의한 분석시, 샘플 표면에서의 charge-up 효과에 의해 분석에 어려움이 있었지만, 본 실험에서는 간편하게 분석이 가능하도록 샘플을 알루미늄 포일(foil)로 감싸서 구리 박막으로부터 실리콘 기판 뒤의 샘플 홀더까지 전기적 접촉이 이루어지도록 하였다. 구리 타겟과 증착된 구리 박막들에 대한 GDMS 분석결과에 의해서, 전체적으로 박막내의 불순물의 양이 음의 기판 바이어스에 의해 줄어듦으로써 구리 박막의 전체 순도를 높일 수 있다는 것을 알게 되었다. 음의 기판 바이어스에 의한 불순물들의 농도변화는 각각의 불순물의 이온화 포텐셜의 차이에 의한 것으로, 박막 증착시 플라즈마내의 Penning ionization effect와 본 논문에서 제시한 이온화 과정에 의해 각 불순물의 농도변화가 설명되어질 수 있었다. 또한, 기판 위에서의 구리 이온들의 충격에 의한 cleaning effect도 박막내의 불순물의 농도변화에 기여했다고 판단된다.