• Journal of Astronomy and Space Sciences
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• v.21 no.4
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• pp.481-492
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• 2004

We report the successful fabrication and I-V curve superconductivity test results of the Nb/Al-based superconducting tunnel junctions. STJs with side-lengths of 20, 40, 60 and $80{\mu}m$ were fabricated by deposition of polycrystalline Nb/Al/AlOx/Al/Nb 5-layer thin films incorporated on a 3-inch Si wafer. STJ was designed by $Tanner^{TM}$ L-Edit 8.3 program, and fabricated in SQUID fabrication facility, KRISS. S-layer STJ thin-films were fabricated using UV photolithography, DC magnetron sputtering, Reactive ion etching, and CVD(Chemical Vapor Deposition) techniques. Superconducting state test for STJ was succeeded in 4K with liquid helium cooling system. Their performance indicators such ie energy gap, normal resistance, normal resistivity, dynamic resistance, dynamic resistivity, and quality factor were measured from I-V curve. Fabricated Nb/Al STJ shows $11\%$ higher FWHM energy resolution than genuine Nb STJ.

• Proceedings of the KIEE Conference
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• 1999.07d
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• pp.1795-1796
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• 1999

ITO thin films have been deposited on PET substrate by reactive dc magnetron sputtering without substrate heater and post heat treatment. The electrical and optical properties of as-deposited films are dominated by oxygen gas ratio. As the experimental results, the excellent ITO films are prepared on PET substrate at the operating conditions as follows: operating pressure of 5 mTorr, target-substrate distance of 4.5 cm, dc power of $20{\sim}30W$, and oxygen gas ratio of 10 %. The optical transmittance is above 80 % at 550 nm, and the sheet resistance and resistivity of films are $24{\Omega}$/square and $1.5{\times}10^{-3}{\Omega}cm$, respectively.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1546-1549
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• 2005

Al-doped ZnO (ZnO:Al) thin films were grown on corning 1737 glass substrates by dc magnetron sputtering. The structural, electrical and optical properties of the films were investigated as a function of various discharge power. The obtained films were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (002) crystallographic direction. The lowest resistivity is $6.0{\times}10^{-4}$ Ocm with the carrier concentration of $2.694{\times}10^{20}$ $cm^{-3}$ and Hall mobility of $20.426cm^2/Vs$. The average transmittance in the visible range was above 90%.

• Proceedings of the KIEE Conference
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• 1998.07d
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• pp.1540-1542
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• 1998

This paper presents the deposition and anneling characteristics of Cr thin film strain gaugs, which were deposited on glass by DC magnetron sputtring. The optimzed deposition conditions of Cr thin films were the input DC power, 7 W/$cm^2$ and the Ar vacuuming pressure, 9 mTorr, GF, TCR and TCS of Cr thin film strain gauges were 5.86, 400 ppm/$^{\circ}C$ and $\approx$0 ppm/$^{\circ}C$ respectively. The anneling conditions were investigated with the thinkness rang (1200 $\sim$ 3500$\AA$) of Cr thin films, anneling temperature (100 $\sim$ $300^{\circ}C$) and anneling time (24 $\sim$ 72hr). The maximum resistivity and the minimum TCR value were 1757.03 ${\mu}{\Omega}$cm, -194.07 ppm/$^{\circ}C$, respectively.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.33 no.2
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• pp.114-117
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• 2020

In this study, we performed the deposition of Al thin film using a DC magnetron sputtering method. To evaluate electrical and structural properties, the growth conditions were changed in terms of two functions, namely, sputtering power ranging from 41.6 to 216 W and film growth rate ranging from 5.35 to 26.39 nm/min. The growth rate and the microstructure were characterized by a scanning electron microscopy and X-ray diffraction analysis. The plane of crystalline growth showed that the preferential (111) direction and defects due to the grain boundary increased with DC power. The resistivity of the Al film over 50 nm showed a constant value by horizontal grain growth. Our results can be applicable for the preparation of nano-templates for anodic aluminum oxide.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.10
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• pp.902-907
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• 2003

In this paper, the ITO thin film, which is considered as one of the most currently used material for the high performance transparent conducting films for the PDP cell, was made in a parallel-plate, capacitively coupled DC magnetron sputtering system. Some electrical and optical properties of ITO films were investigated and discussed on the basis of glow discharge characteristics. The optimized thin film fabricating conditions of Ar gas pressure and substrate temperature were derived from the Paschen curve and glow discharge characteristics. The maximum transmittance of 89.61 % in the visible region and optical band gap of 3.89 eV and resistivity of 1.67${\times}$10$\^$-3/ $\Omega$-cm were obtained under the conditions of 300 C of substrate temperature and 10∼15 mtorr of pressure, which corresponds nearly to that of Paschen minimum.

• Journal of the Korean Society for Heat Treatment
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• v.22 no.3
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• pp.143-148
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• 2009

We have fabricated Ti metal films on Cu wire substrates by using a RF magnetron sputtering method at different RF powers (0, 30 and 60 W) in a high vacuum, and we have investigated the thin film characteristics and resistivity. The ion bombardment effect is increased by the method to superimpose RF power to DC power applied to two poles of the base; thus, the thin film is deposited at sputtering gas pressures below 1 Pa. Moreover, the thin film formation of the multilayer structure becomes possible by gradually injecting the RF power, and the thin film quality is improved.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.56 no.4
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• pp.157-160
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• 2007

The van der Pauw technique is one of the popular methods for determining the conductivity of flat metal samples. Traceability of the national standard for the conductivity has been achieved by direct current measurement techniques in national measurement institutes of many countries. But recently, alternative current measurement techniques for determining the conductivity of flat metal samples is also interested. In this study, we measured the conductivity of non-ferrous and ferrous flat metals at alternative current using van der Pauw technique. As measurement results, the conductivities of the samples were decreased according to increasing the test frequency even though the decreasing ratio was different.

• Korean Journal of Materials Research
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• v.16 no.6
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• pp.346-350
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• 2006

Al-doped ZnO (AZO) thin films were grown on type of glass#1737 substrates by DC magnetron sputtering. The structural, electrical and optical properties of the films were investigated as a function of various plasma discharge power. The obtained films were polycrystalline with a hexagonal wurtzite structure and preferentially oriented in the (002) crystallographic direction. The lowest resistivity was $6.0{\times}10^{-4}{\Omega}cm$ with the carrier concentration of $2.69{\times}10^{20}cm^{-3}$ and Hall mobility of 20.43 $cm^2/Vs$. The average transmittance in the visible range was above 90%.

• Korean Journal of Materials Research
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• v.11 no.6
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• pp.492-497
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• 2001

We report the characteristics and the dependence of sputter-deposited Ta films on the process parameters. The properties of as-deposited Ta films such as deposition rate, resistivity, Rs uniformity, reflectivity, and stress were investigated and analyzed as a function of process parameter using a statistical experimental method. The functional relationships between the independent and dependent variables were predicted by surface response. The optimal deposition condition of DC magnetron sputtered Ta films was obtained at the chamber pressure of 2 mTorr, power density of 8 W/$\textrm{cm}^2$, and substrate temperature of 2$0^{\circ}C$ by means of resistivity and Rs uniformity. The fitness value for quadratic model as evaluated by the R- square was 0.85~ 0.9 without pooling. The as-deposited Ta films exhibited the resistivity of ~180$\mu$$\Omega$cm with Rs uniformity of ~2%. The transmission electron microscopy and x-ray diffractometry identified that the phase of as-deposited film was $\beta$-Ta having the grain size of 100~200.