• Journal of Surface Science and Engineering
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• v.35 no.2
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• pp.113-121
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• 2002

We have investigated insulating properties of $SiO_2$ interlayer for the thin film strain gauge, which were prepared by RF magnetron sputtering method in various deposition conditions, such as Ar pressure, gas flow rates and sputtering gases. SEM, AFM and FT-IR techniques were used to analyze its structures and composition. As the Ar pressure and the flow rate increased, the insulating interlayer showed low insulating resistance due to its porous structure and defects. Oxygen deficiency in $SiO_2$ was decreased as fabricated by hydrogen reactive sputtering. We could enhance the surface mobility of sputtered adatoms by using Ar/$H_2$ sputtering gas and obtain a good surface roughness and insulating property. The optimum insulating resistance of 9.22 G$\Omega$ was obtained in Ar/30% $H_2$ mixed gas, flow rate 10sccm, and 1mTorr.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11b
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• pp.537-540
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• 2001

This paper presents the characteristics of Ta-N thin-film for high precision resistors, which were deposited on Si substrate by DC reactive magnetron sputtering in an argon-nitrogen atmosphere(Ar-(4~16 %)$N_2$). Structural properties studied using X-ray diffraction(XRD) indicate the presence of TaN, $Ta_3N_5$ or a mixture of Ta-N phases in the films depending on the amount of nitrogen in the sputtering gas. The chemical composition are investigated by auger electro spectroscopy(AES). The optimized conditions of Ta-N thin-film resistors were deposited in 4 % $N_2$ gas flow ratio. Under optimum conditions, the Ta-N thin-film resistors are obtained a high resistivity, $\rho=305.7{\mu}{\Omega}cm$, a low temperature coefficient of resistance, TCR=-36 $ppm/^{\circ}C$.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.11a
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• pp.537-540
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• 2001

This paper presents the characteristics of Ta-N thin-(ibm for high precision resistors, which were deposited oni substrate by DC reactive magnetorn sputtering in an argon-nitrogen atmosphere(Ar-(4∼16%)N$_2$). Sturcutural properties sutided using X-ray diffraction (XRD) indicate the presence of TaN, Ta$_3$N$\sub$5/ or a mixture of Ta-N phases in the films depending on the amount of nitrogen in the sputtering gas. The chemical composition are investigated by auger electro spectroscopy(AES). The optimized conditions of Ta-N thin-film resistors were deposited in 4 % N$_2$ gas flow ratio. Under optimum conditions, the Ta-N thin-film resistors are obtained a high resistivity, $\rho$=305.7 ${\mu}$Ωcm, a low temperature coefficient of resistance, TCR=-36 ppm/$^{\circ}C$.

• Korean Journal of Materials Research
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• v.9 no.2
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• pp.163-167
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• 1999

LiNbO$_3$films were prepared by an rf-magnetron sputtering technique using sintered target containing potassium. The potassium was included to help to fabricate stoichiometric LiNbO$_3$film. Structural and electrical properties of thin films was investigated as a function of deposition condition. Optimum sputtering conditions were rf power of 100W, working pressure of 1m Torr and substrate temperature of 58$0^{\circ}C$. The thin film was grown to (012) preferred orientation. The dielectric constant of the thin film LiNbo$_3$ fabricated under optimum condition was 55 at 1MHz. Average grain size is about 200$\AA$ and roughness of the film is small enough to apply to optic devices.

• Journal of the Korean Vacuum Society
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• v.5 no.2
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• pp.139-146
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• 1996

Transparent and conducting Sb-doped $SnO_2$ thin films were prepared by rf magnetron sputtering technology. But it showed a serious damage phenomenon on the surface of as-deposited films. In order to avoid a damage caused in the substrate center and location facing to target erosion, a ring plate of masking glass was installed at 1.5 cm above target surface. The uniformity and electrical characteristic of $SnO_2$ thin films were evaluated by the control of optimal conditions in the magnetron sputtering operation such as rf power, sputtering gas pressure, and substrate temperature. In the experimental results using the operating conditions, the optimum temperature, which produced uniform and damageless films, shifted with the change of gas pressure. The rate was about $100^{\circ}C$/5 mTorr at rf power of 50 W Similarly, the optimum temperature in compensation for an increase of rf power shifted down to a proper rate.

• Journal of the Korean Ceramic Society
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• v.34 no.8
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• pp.908-913
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• 1997

Multilayer NbCxC1-x/Y2O3/Ti were sputter-coated on the alumina substrate, starting with a 0.7 ㎛ thick NbCxC1-x layer grown on substrate, followed by 0.7 ㎛ thick Y2O3 layer and 1 ㎛ thick Ti layer. To find out the optimum conditions for thickness uniformity and adhesion, sputtering works have been done with the variation of sputtering power and Ar pressure. After vacuum annealing at 950℃ and 1000℃, the thermal stability of the NbCxC1-x/Y2O3/Ti coated alumina substrates has been investigated by peel off test. The coating scheme didn't cause any debonded layer after an annealing at 950℃ for 3hrs. However, it was peeled off after annealing at 1000℃ for 3hr. It was found that the thermal stability of Al2O3/NbCxC1-x/Y2O3/Ti coating scheme changed with the NbCxC1-x composition.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.10
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• pp.436-440
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• 2003

The (S $r_{0.85}$C $a_{0.15}$)Ti $O_3$(SCT) thin films were deposited on Pt-coated electrode(Pt/TiN/ $SiO_2$/Si) using RF sputtering method according to the deposition condition. The optimum conditions of RF power and Ar/ $O_2$ ratio were 140[W] and 80/20, respectively. Deposition rate of SCT thin films was about 18.75[$\AA$/min] at the optimum condition. The composition of SCT thin films deposited on Si substrate is close to stoichiometry (1.102 in A/B ratio). The capacitance characteristics had a stable value within $\pm$4[%]. The drastic decrease of dielectric constant and increase of dielectric loss in SCT thin films were observed above 200[kHz]. SCT thin films used in this study showed the phenomena of dielectric relaxation with the increase of frequency.ncy.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.243-246
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• 2000

The sputtering systems mainly consist of the three-target holder. The target and substrate were the on-axis type. The MgO and STO substrate were used for the deposition of each layer. The optimum conditions of single-layer thin film were investigated from the SEM images and the XRD patterns. Based on the above conditions, the multi-layer thin films such as YBaCuO/LaGaO/Au/Nb and YBaCuO/Au/Nb were fabricated. The crystalline, the electrical Properties, the energy gap structure and the characteristics of the tunneling barrier on the multi-layer thin film have been investigated and characterized.

• Korean Journal of Materials Research
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• v.12 no.1
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• pp.82-88
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• 2002

Chromium carbide films were deposited on high speed steels using a Cr_3C_2$ target by magnetron sputtering. Effects of the deposition parameters (power, Ar pressure and substrate temperature) on deposition rates and surface roughnesses of the films were investigated. The morphologies of those films were characterized by scanning electron microscopy and atomic force microscopy. The grain size of the samples deposited using dc-power is larger than that using equivalent rf-power. The hardness of the sample increases with increasing rf-power, whereas the elastic modulus nearly does not change with rf-power. The optimum sputter deposition conditions for chromium carbide on high speed steels in the corrosion resistance aspect were found to be the rf-power with small roughness.

• Journal of Surface Science and Engineering
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• v.29 no.5
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• pp.424-429
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• 1996

Thin films of Ti-Ni alloy were formed by sputtering under various Ar gas pressures and r. f. powers to investigate the optimum sputtering conditions and to demonstrate their shape memory effect. The composition and structure of the films were examined by electron micro-probe analysis and scanning electron microscope. These films were annealed in order to crystallize them. The mechanical property of the annealed films was evaluated by a conventional bending test. The transformation tmeperatures were determined by differential scanning calorimetry. The shape memory behaviour was examined quantiatatively by changing in sample temperature under various constant loads. It was found that the Ar gas pressure had a critical effect on the mechanical property of the thin film,s although the r.f. power also affected it. The films formed at a high Ar gas pressure were too brittle to be bent successfully. However, the films formed at a low Ar gas pressur could be bent and their shape memory behavior was found to be comparable with that of bulk Ti-Ni alloys.