• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.173.1-173.1
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• 2014

The variations of electronic and magnetic properties of ultrathin Fe overlayers on a W(001) surface as a function of Fe film thickness (1.0~4.0 ML) has been investigated using x-ray magnetic circular dichroism (XMCD) in conjunction with ultraviolet photoelectron spectroscopy (UPS) and low energy electron diffraction (LEED). We found that the ferromagnetic property of Fe film started to build up over 2.0 ML, as we confirmed the spin and angular moment contribution to the magnetic moment using XMCD experiments. We will systematically demonstrate that the occurrence of ferromagnetic property of Fe film on a W(001) surface is closely correlated to a themally stable layer of Fe film on a W(001) surface.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.11a
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• pp.370-374
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• 2002

Many compound semiconductors which have high carrier mobility and small band gap have attentive in application of various practical a field. Especially, InSb served for Hall device and magnetic resistor such as magnetic sensor because InSb thin film has high mobility. Many studies on InSb thin film deposistion because In and Sb has been very different feature of vapor pressure ($10^{-4}$ times) When In and Sb deposited. In this paper studied it In and Sb deposited simultaneously using by method of co-sputtering deposotion. This process, get to effects of manufacture process simplification. After that this paper observed micro structure and electronic behavior of InSb thin film using by co-sputtering and we study properties of magneto-resistance by annealing.

• Journal of the Korean Magnetics Society
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• v.11 no.3
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• pp.109-113
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• 2001

Presently, an inductor adapted at MMIC (Monolithic Microwave Integrated Circuit) which is used for cellular phone or PHS operates at quasi-microwave range over 800 MHz. However, a W-CDMA (Wideband Code Division Multiple Access) will use about 2 GHz range. Therefore magnetic film device should be compatible up to 2 GHz. We have deposited Co-Pd-Al-O system film using rf sputtering method which is expected up to 2 GHz, and investigated the effect of Pd content and magnetic field annealing. When Pd composition is 19%, Hk was 118 Oe, and ${\mu}$′showed flat frequency characteristics up to 1.5 GHz. The Q factor (=${\mu}$′/${\mu}$") was 23.3 at 1 GHz, 6.7 at 1.5 GHz and 1.5 at 2 GHz, respectively. Resonance frequency was 2 GHz. Therefore Co-Pd-Al-O thin film could be used at over 1 GHz, and also expected as an inductor material for wide band CDMA type cellular phone.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.08a
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• pp.128-132
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• 2002

Many compound semiconductors which have high carrier mobility and small band gap have attentive in application of various practical a field. Especially, InSb served for Hall device and magnetic resistor such as magnetic sensor because InSb thin film has high mobility. Many studies on InSb thin film deposistion because In and Sb has been very different feature of vapor pressure($10^{-4}$ times) When In and. Sb deposited. In this paper studied it In and Sb deposited simultaneously using by method of co-sputtering deposotion. This process, get to effects of manufacture process simplification. After that this paper observed micro structure and electronic behavior of InSb thin film using by co-sputtering and we study properties of magneto-resistance by annealing

• Proceedings of the KSME Conference
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• 2007.05b
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• pp.3098-3103
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• 2007

In this paper, natural convection of a magnetic fluids(W-40) in a half circular pipe enclosure are investigated by numerical and experimental method. One side wall is kept at a constant temperature(25$^{\circ}C$), and the opposite side wall is also kept at a constant temperature(20$^{\circ}C$). Under above conditions, various magnitudes of the magnetic fields were applied up. Theoretical study through the governing equation derived by Siliomis is carried out with numerical analysis by the GSMAC Method. And the thermo-sensitive liquid crystal film(R20C5A) is utilized in order to visualize wall-temperature distributions as an experimental method. This study has resulted in the following fact that the natural convection of a magnetic fluids are controlled by the direction and intensity of the magnetic fields.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.208-211
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• 2000

We prepared Co-Cr-Ta and Co-Cr-Ta/Ti thin film for perpendicular magnetic recording media by facing targets sputtering system (FTS system). Ti underlayer effects on crystallographic and magnetic characteristics of Co-Cr-Ta perpendicular magnetic recording media have been investigated. Crystallgraphic and magnetic characteristic of prepared thin films were evaluated by x-ray diffractometry(XRD), vibrating sample magnetometer(VSM) and kerr hysteresis loop measurement. The coercivity and anisotropy field increase by introduced Ti underlayer when substrate temperature is higher than 150$^{\circ}C$. The c-axis dispersion angle and grain size of Co-Cr-Ta/Ti thin film is decrease than Co-Cr-Ta when substrate temperature is higher than 100$^{\circ}C$. Consequently, the use of a Ti underlayer highly orientated can be improved crystallographic and magnetic characteristics of Co-Cr -Ta perpendicular media layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.17 no.1
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• pp.52-58
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• 2004

Magneto-Impedance(MI) sensor is a highly sensitive sensor, which was able to detect a weak geomagnetic field. It also has a merit to be able to build in the low power system. In this study, their magnetic permeability and anisotropy field(H$\sub$k/) as a function of some different thickness of sputtered amorphous CoZrNb films with zero-magnetostriction and soft magnetic property are investigated. In order to make a uniaxial anisotropy, film was subjected to the post annealing in a static magnetic field with 1KOe intensity at 250, 300, and 320$^{\circ}C$ respectively for 2 hours. Magnetic properties of films are measured by using a M-H loop tracer. Magnetic permeability of a film is measured over the frequency range from 1 ㎒ to 750㎒. By thickening a CoZrNb film relatively, magnetic permeability and impedance are examine to design the. MI sensor which drives at 50㎒, and thereof fabricated the MI sensor which drives at the 50㎒.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.11
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• pp.963-968
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• 2000

Magnetic properties and microstructures of Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films were investigated as a function of addition of element Ag, (X$\_$Ag/=0 to 6 at.%) and annealing temperature, T$\_$a/=300$\^{C}$ to 600$\^{C}$. In the case of adding Ag, magnetic properties of Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films were improved than those of Ag-free Fe$\_$93/Zr$_3$B$_4$thin films. The prominent soft magnetic properties with coercivity of 1.1 Oe, saturation magnetization of 2.2 T and permeability of 5400 at 50㎒ were obtained from Fe$\_$88/Zr$_3$B$_4$Ag$\_$5/ thin film annealed was lower than that of Fe-base or Co-base thin films reported previously. Such enhanced magnetic properties are presumably attributed to the format in ultra fine grains. Also, the reduced eddy current loss in the annealed sample is due to refined micro magnetic domains with increasing the amount of Ag in Fe$\_$93-x/Zr$_3$B$_4$Ag$\_$x/ thin films.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.5
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• pp.411-414
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• 2009

It has been investigated for the film uniformity and deposition rate of a-C:H films on glass substrate and polymeric materials in the presence of the modulated crossed magnetic field. We used Plasma CVD, i.e, using a crossed electromagnetic field, for uniform depositing thin film. The optimum discharge condition has been discussed for the gas pressure, the magnetic flux density and the distance between substrate and electrodes, As a result, it is found that the optimum discharge conditions are $CH_4$ concentration $CH_4$=10 %, modulated magnetic flux density B=48 Gauss, pressure P=100 mTorr, discharge power supply voltage V=l kV under these experimental conditions. By using these experimental condition, it is possible to prepare the most uniform film extends over about 160 mm of the film width. In this study, we deposited a-C:H thin film on glass substrate, and have a plan that using this condition, study depositing a-C:H thin film on polymeric substrate in next studies.

• Korean Journal of Materials Research
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• v.23 no.9
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• pp.517-524
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• 2013

The electrical and optical properties of fluorine-doped tin oxide films grown on polyethylene terephthalate film with a hardness of 3 using electron cyclotron resonance plasma with linear microwave of 2.45 GHz of high ionization energy were investigated. Fluorine-doped tin oxide films with a magnetic field of 875 Gauss and the highest resistance uniformity were obtained. In particular, the magnetic field could be controlled by varying the distribution in electron cyclotron deposition positions. The films were deposited at various gas flow rates of hydrogen and carrier gas of an organometallic source. The surface morphology, electrical resistivity, transmittance, and color in the visible range of the deposited film were examined using SEM, a four-point probe instrument, and a spectrophotometer. The electromagnetic field for electron cyclotron resonance condition was uniformly formed in at a position 16 cm from the center along the Z-axis. The plasma spatial distribution of magnetic current on the roll substrate surface in the film was considerably affected by the electron cyclotron systems. The relative resistance uniformity of electrical properties was obtained in film prepared with a magnetic field in the current range of 180~200A. SEM images showing the surface morphologies of a film deposited on PET with a width of 50 cm revealed that the grains were uniformly distributed with sizes in the range of 2~7 nm. In our experimental range, the electrical resistivity of film was able to observe from $1.0{\times}10^{-2}$ to $1.0{\times}10^{-1}{\Omega}cm$ where optical transmittance at 550 nm was 87~89 %. These properties were depended on the flow rate of the gas, hydrogen and carrier gas of the organometallic source, respectively.