• Proceedings of the Korean Vacuum Society Conference
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• 1998.02a
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• pp.19-19
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• 1998

Scanning pprobe Microscoppy (SppM) is a ppowerful surface chracterization technology which can measure not only surface toppograpphy but also various ppropperties of the sampple with unpprecedented sensitivity and sppatial resolution. Recent developpment of electrostatic force microscoppe (EFM) and scanning cappacitance microscoppe (SCM) allows us to measure surface ppotential distribution and cappacitance variation n semiconductor devices. The cappacitance image pprovide us valuable information on carrier density and dopping pprofile.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.9 no.1
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• pp.29-33
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• 1999

Transition metallic $Cr^{3+}$ ion was diffused in white sapphire {0001}, ${10\bar{1}0}$ crystal plane which were grown by the Verneuil, it enhanced and changed the physical, electrical and optical properties of sapphires. After mixing the metallic oxide and metal powder, it were used for diffusion powder. When it was used the mixing powder of metal and metallic oxide, the dopping was slowly progressed and it needed the longer duration time and higher temperature, relatively. Metallic powder was vapoured under $1{\times}10^{-4}$ torr of vacuum pressure at $2050^{\circ}C$, first step, it were kept by the diffusion condition of 6 atm of $N_{2}$ accelerating pressure at $2050~2150^{\circ}C$. Each surface density of sapphire crystal are 0.2254(c) and $0.1199\;atom/{\AA}^2(a)$. The color of the Cr-doped sapphires was changed to red. Dopping reaction was come out more deep in the plane of ${10\bar{1}0}$ than {0001}. It was speculated that the planar density was one of the factors to determine diffusion effect.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2001.07a
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• pp.806-808
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• 2001

In this thesis, specimens was manufactured in general method annexing PMB-PZT system ceramic, and the following conclusion has been deduced. In XRD, the crystal structure of ceramic has the tetragonal structure which is close to rombohedral structure, and consequently the specimen characterized by MPB was manufactured. According to dopping with xPMB, electromechanical factor(kp) little is changed. kp was maximum value 23.37[%] at xPMB 0.03[mol%]. mechanical quality factor(Qm) was maximum value 237.04 at xPMB 0.03[mo1%].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.650-652
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• 2002

In this paper, specimens was manufactured in general method annexing PAN-PZT+0.8wt%Mn+1wt% Nb ceramics doped by Sr(0.0 ~ 1.2 wt%). and the following conclusion has been deduced. In XRD, the crystal structure of ceramic has the rombohedral structure and consequently the specimen characterized by MPB was manufactured. According to dopping with Sr, electromechanical factor(kp) little is changed. kp was maximum value 31.31[%] at Sr 1.2[wt%]. mechanical quality factor(Qm) was maximum value 371.879 at Sr 0.6[wt%].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2002.07b
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• pp.578-580
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• 2002

In this thesis, specimens was manufactured in general method annexing PMB-PZT system ceramic, and the following conclusion has been deduced. In XRD, the crystal structure of ceramic has the tetragonal structure which is close to rombohedral structure, and consequently the specimen characterized by MPB was manufactured. According to dopping with xPMB, electromechanical factor(kp) little is changed. kp was maximum value 23.37[%] at xPMB 0.03[mol%]. mechanical quality factor(Qm) was maximum value 237,04 at xPMB 0.03[mol%].

• Proceedings of the KIEE Conference
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• 2001.07c
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• pp.1524-1526
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• 2001

In this thesis, specimens was manufactured in general method annexing PMB-PZT system ceramic, and the following conclusion has been deduced. In XRD, the crystal structure of ceramic has the tetragonal structure which is close to rombohedral structure, and consequently the specimen characterized by MPB was manufactured. According to dopping with xPMB, the dielectric constant at 20[$^{\circ}C$] reduced on the whole, dielectric constant was maximum value $8.0{\times}10^2$ at xPMB 0.01[mol%]. Dielectric loss was maximum value 4.1[%] at xPMB 0.01[mol%].

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.464-467
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• 2004

An uncooled infrared sensor has been prepared with sputtering, plasma ash, ICP, and PECVD on a Si wafer In order to analyze the resistance characteristics with the bridge length in the infrared sensor, three samples were prepared with lengths of 0 (no bridge), 15 (short bridge), and 29 urn (long bridge), respectively. I-V curves were measured for their resistance characteristics and EPMA for the dopping concentration of the amorphous Si. The phosphorus concentration was about 4 % and the resistance was increased with the bridge length. The bridge length of cantilever is very important factor for improvement of the efficiency in an infrared sensor.

• Journal of the Korean Chemical Society
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• v.35 no.6
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• pp.725-729
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• 1991

Unsaturated all-cis-5,8,11,14-eicosatetraenoic(arachidonic), 7,10,13-hexadecatrienoic, 10, 13-octadecadienoic acid ethyl ester and a lot of chimyl alcohol were isolated along with common 9-hexadecenoic acid ethyl ester from marine mollusca Bullacta exarata collected from sangnackworl island in the Korea sea. In addition, cholesterol and its fatty acid ester were obtained. Their structures were deduced from $^1H-$and $^{13}C$-NMR, GC-ms, and FT-IR spectra.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.230.1-230.1
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• 2014

대면적 그래핀의 높은 제조비용과 낮은 생산성으로 인해 최근 산화그래핀(GO)을 박리하여 대면적화 하는 연구가 활발히 진행되고 있다. 하지만, Hummers 법에 의해 제조된 산화그래핀은 제조공정상 발생되는 황이나 수소 및 산소 등의 불순물에 의한 특성저하와 15층에서 25층 정도의 다층 구조에 의한 높은 접촉저항 때문에 그래핀 고유의 특성 발휘가 어렵다. 본 연구에서는 DC 열 플라즈마의 NH3 방전을 이용하여 산화그래핀의 불순물인 S, H, O를 완전히 제거하였고, DC 열 플라즈마 처리된 후의 산화그래핀의 Volume을 평균 2.5배정도 증가시켰다. 또한 N2와 He을 혼합 시킨 DC 열 플라즈마 방전으로 산화그래핀 표면에 N 을 도핑 하여 전기적 특성을 향상시켰다. N 도핑 농도는 최대 20wt%이었으며 N2과 He공급량, Current 조절에 의해 Dopping 농도를 제어하였다.

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.60-66
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• 1992

The electronic subband structure and the envelope wave function for three types of superlattices are calculated with a new method. Comparison of the results of this method with those of other methods has proved the validity of this method. In particullas, the results of saw-toothed superlattices show that the change of the effective mass with position must be considered. Therefore this method can be easily applied to arbitrily shaped superlattices and multiple quantum well structures.