• Journal of the Korean Magnetics Society
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• v.7 no.2
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• pp.82-89
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• 1997

Dependence of magnetoresistance on the thickness of Cu, type and thickness of buffer layer, and the stacking number of multilayer in the form buffer /$[Co(17{\AA}/Cu(t{\AA})]_{20}$ were investigated. To evaluate effect of annealing on this samples, X-ray diffraction analysis, vibrating sample magnetometer analysis, and magnetoresistance measurement (4-probe method) were performed. The magnetoresistance ratio exhibits a maximum of 21% for the multilayer with Cu thickness of 24$\AA$ and Fe buffer layer thickness of 50$\AA$. Deposition of film under low base pressure induces in increase magnetoresistance ratio by preventing oxidation. The multilayer annealed below 30$0^{\circ}C$ temperature allowed larger textured grain without loss in the periodicity. Magnetoresistance ratios of the multilayer with Cu thickness of 24$\AA$ and 36$\AA$ were increased due to the increase in the antiferromagnetically coupled fraction after annealing.

• Journal of the Korean Magnetics Society
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• v.14 no.1
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• pp.25-28
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• 2004

The dependence of sensitivity, MR ratio, coercivity (Hc) and switching fields as a function of thickness of each magnetic layers(Co, NiFe and Cu) were investigated in pseudo spin valves with a structure of Ta/NiFe/Cu/Co. As measured results dependence of the thickness of each magnetic layer, we obtained MR ratio of 7.26% for Ta(4 nm)/NiFe(7.5 nm)/Cu(3 nm)/Co(5 nm) pseudo spin valves. Also, we could control properties of magnetoresistance for independent magnetization courses of each magnetic layer. Especially, we found that we could control coercivity as constant MR ratio dependence of Co thickness.

• Journal of the Korean Magnetics Society
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• v.3 no.4
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• pp.289-292
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• 1993

[Ni/Fe/Cu] and [Fe/Ni/Fe/Cu] multilayers were prepared with three gun rf-magnetron sputtering, and dependence of magnetoresistance on the Ni IFe thickness ratio was investigated. Vaccum annealing was tried to invetigated the effect of annealing. Oscillation of magnetoresistance on the Cu spacer thickness was dbserved in these two kinds of multilayers. When the thickness of Fe inserted into the Ni/Cu interface was about $3\;\AA$. the maximum value of magnetoresistance(13 %) could be observed. In a sample of $1~2\;\AA$ Fe thickness, saturation field decreased significantly, while magnetoresistace decreased slightly in comparison with the sample of $3\;\AA$ Fe. In ${[Cu(23\;\AA)/Fe(1\;\AA)/Ni(18\;\AA)/Fe(1\;\AA)]}_{20}/Fe(80\;\AA)/Si$, 6 % magnetoresistance with 100 Oe saturation field could be obtained. No appreciable change in magnetoresistance and saturation field could be observed by low temperature annealing. Formation of Ni-Fe alloy was not confinred.

• Journal of Welding and Joining
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• v.31 no.5
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• pp.54-58
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• 2013

Joint properties of vehicle ECU (Electric Control Unit) module which was manufactured by using Sn-Cu-Cr-Ca alloy were investigated. A new solder which has a middle melting temperature about $231^{\circ}C$ was fabricated as the type of 300um solder ball and paste type. The prototype modules were made by reflow process and measured spreadability, wettability shear strength and estimated interface reaction. The spreadability of the alloy was about 84% from the measurement of contact angle of the solder ball and the wetting force was measured 2mN. The average shear strength of the module which was manufactured by using the solder paste, was 1.9 $kg/mm^2$. Also, the thickness of IMC(intermetallic compound) was evaluated with various aging temperature and time in order to understand Cr effect on Sn-0.7Cu solder. $Cu_6Sn_5$ IMC was formed between Cu pad and the solder alloy and the average thickness of the $Cu_6Sn_5$ IMC was measured about 4um and it was about 50% of thickness of $Cu_6Sn_5$ IMC in Sn-0.7Cu. It is expected to have a positive effect on reliability of the solder joint.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.21 no.10
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• pp.930-933
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• 2008

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET device was made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40 nm, and the channel length was $50{\mu}m$, channel width was 3 mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.389-390
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• 2008

We fabricated organic field-effect transistors (OFETs) based a fluorinated copper phthalocyanine ($F_{16}CuPc$) as an active layer. And we observed the surface morphology of the $F_{16}CuPc$ thin film. The $F_{16}CuPc$ thin film thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed the typical current-voltage (I-V) characteristics and capacitance-voltage (C-V) in $F_{16}CuPc$ FET and we calculated the effective mobility.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2008.10a
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• pp.619-621
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• 2008

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET device was made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.506-507
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• 2008

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40nm, and the channel length was $50{\mu}m$, channel device was width was 3mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04b
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• pp.12-13
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• 2008

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET device was made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.494-495
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• 2007

Organic field-effect transistors (OFETs) are of interest for use in widely area electronic applications. We fabricated a copper phthalocyanine (CuPc) based field-effect transistor with different metal electrode. The CuPc FET device was made a top-contact type and the substrate temperature was room temperature. The source and drain electrodes were used an Au and Al materials. The CuPc thickness was 40nm, and the channel length was $50{\mu}m$, channel width was 3mm. We observed a typical current-voltage (I-V) characteristics in CuPc FET with different electrode materials.