• 전자공학회논문지
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• 제51권4호
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• pp.193-200
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• 2014

본 논문에서는 방사성 의약품의 자동합성장치에 사용되는 단채널 감마선 분광기를 보드 형태로 설계, 제작하고 그 특성을 측정 분석하였다. 감마선 검출을 위해 CZT (CdZnTe) spear 검출기를 이용하였고 아날로그 방식을 적용한 신호처리 보드의 형태로 감마선 분광기를 제작하였다. 측정을 위하여 방사성 물질인 Co-60을 시료로 사용하였으며, 최대 1173keV까지의 감마선 에너지 스펙트럼을 얻을 수 있었다. 아날로그 보드는 CZT spear 검출기에서 감마선을 검출하여 출력하는 신호를 적절히 변화시켜주기 위한 SF (shaping filter) 및 PHA (peak and hold amplifier)와 수치화된 감마선 신호 데이터를 계산하기 위한 ADC(analog to digital converter)와 FPGA (field programmable gate array)로 구성되었다.

• 전자공학회논문지D
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• 제34D권4호
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• pp.47-53
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• 1997

We fabricated gamma radiation detector using high resistive p-Cd$_{80}$Zn$_{20}$Te grown by high pressure bridgman method and forming au thin film electrode by chemically electroless deposition method. The device of Au/Cd$_{80}$Zn$_{20}$Te/Au is a typical MIM structure. The characteristic of current-voltage showed good linearity to 3kV/cm but it depend on the square of electric field over 3kV/cm. As the results of rutherford backscattering spectroscope(RBS) and auger spectroscope on the Au/Cd$_{80}$Zn$_{20}$Te, Au penetrated to the surface of Cd$_{80}$Zn$_{20}$Te detector absorbed slightly high energy radiation like a few hundred keV and showed good performance to detect low energy gamma ray.mma ray.

• 한국세라믹학회지
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• 제56권3호
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• pp.291-297
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• 2019

Pyrolytic carbon (PyC) layers were deposited using methane. The PyC layer deposited with 5% methane showed highly textured graphite, while that deposited using 100% methane showed low textured graphite. The degrees of anisotropy of the carbon layers were measured using an X-ray diffractometer, a transmission electron microscope, and a Raman spectroscope, and the results were compared with those reported previously. The orientation angles obtained from the fast Fourier transformation of the high-resolution transmission electron microscopy images and the I_D/I_G intensity ratios obtained from the Raman spectra were used to evaluate the anisotropy of the PyC layers.

• 대한전기학회논문지:전기기기및에너지변환시스템부문B
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• 제55권11호
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• pp.555-563
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• 2006

This paper presents the measured radiation intensity of high-pressure and large-current arc with the current. In order to measure the radiation intensity of large-current arc, a model circuit breaker was specially designed and manufactured and the method using an astronomical telescope was utilized after various measuring methods were investigated. A trigger system was designed and fabricated to coincide the time of desired current with the exposure time of 1ms of the spectroscope. A high-speed camera was used to investigate the shape and behavior of the arc and the captured results have been used to calculate the radiation energy. The calculated arc temperature with Boltzmann plot method using the measured radiation intensity have $18,000{\sim}27,000K$ to the current $4kA{\sim}15kA$. And also, using the calculated arc temperature and the captured arc shape the radiation energy of the current $5kA{\sim}15kA$ were calculated with $8{\times}10^5{\sim}4.0{\times}10^6W/m$ respectively.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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• pp.381.1-381.1
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• 2014

In this study, we investigated the deposition behavior and the etch resistivity of plasma polymerized carbon hardmask (ppCHM) film with the variation of process temperature. The etch resistivity of deposited ppCHM film was analyzed by thickness measurement before and after direct contact reactive ion etching process. The physical and chemical properties of films were characterized on the Fourier transform infrared (FT-IR) spectroscope, Raman spectroscope, stress gauge, and ellipsometry. The deposition behavior of ppCHM process with the variation of temperature was correlated refractive index (n), extinction coefficient (k), intrinsic stress (MPa), and deposition rate (A/s) with the hydrocarbon concentration, graphite (G) and disordered (D) peak by analyzing the Raman and FT-IR spectrum. From this experiment we knew an optimal deposition condition for structure of carbon hardmask with the higher etch selectivity to oxide. It was shown the density of ppCHM film had 1.6~1.9 g/cm3 and its refractive index was 1.8~1.9 at process temperature, $300{\sim}600^{\circ}C$. The etch selectivity of ppCHM film was shown about 1:4~1:8 to undoped siliconoxide (USG) film (etch rate, 1300 A/min).

• 한국표면공학회지
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• 제41권2호
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• pp.43-47
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• 2008

Cubic boron nitride(c-BN) films were deposited on tungsten carbide insert tool by microwave plasma enhanced chemical vapor deposition(MPECVD) from a gas mixture of triethyl borate$(B(C_2H_5O)_3)$, ammonia $(NH_3)$, hydrogen$(H_2)$ and argon(Ar). The qualities of deposited thin film were investigated by x-ray diffrac-tion(XRD), field emission scanning electron microscopy(FE-SEM) and micro Raman spectroscope. The surface morphologies of the synthesised BN as well as crystallinity appear to be highly dependent on the flow rate of $B(C_2H_5O)_3$ and $(NH_3)$ gases. The deposited film had more crystallized phases with 5 scem of $B(C_2H_5O)_3$ and $(NH_3)$ gases than with 2 sccm, and the phase was identified as c-BN by micro Raman spectroscope and XRD. The adhesion strength were also increased with increasing flow rates of $B(C_2H_5O)_3$ and $(NH_3)$ gases.

• Korean Chemical Engineering Research
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• 제43권4호
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• pp.495-502
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• 2005

무전해 도금 용액을 이용하여 구리를 직접 텅스텐(Tungsten, W) 기판 위에 도금하였다. 도금 용액의 농도는 각각 $CuSO_4$ 7.615 g/L, EDTA 10.258 g/L, glyoxylic acid 7 g/L로 하였다. 도금 용액의 pH는 11.0에서 12.8까지 변화시켰으며, 용액의 온도는 $60^{\circ}C$로 유지하였다. 도금된 필름의 특성을 조사하기 위하여 X선 회절분석기, 전계 방출 주사 전자 현미경, 주사형 원자력 현미경, X선 광전자 분석기 및 Rutherford backscattering spectroscope(RBS)를 사용하였다. 구리 도금을 위한 가장 좋은 pH 조건은 11.8이였다. 이 용액에서 10분 동안 도금한 경우 둥근 모양의 구리 입자가 균일하게 도금되었으며, 불순물 peak이 없는 순수 구리 peak이였고, 근평균 제곱 표면 거칠기는 약 11 nm가 되었다. 또한, pH 11.8에서 12분 동안 도금한 필름의 두께는 140 nm이었고 도금속도는 약 12 nm/min였다. 무전해 도금 용액의 pH를 12.8로 증가시키면 도금된 구리 필름은 Cu peak 이외에 불순물 peak인 $Cu_2O$가 나타나고 구리 입자 모양도 기다란 직사각형 모양으로 변하였다. 순수 구리의 도금을 위해서는 도금 용액에서 적당한 pH를 유지하여야 한다. 도금된 구리의 농도는 RBS로 측정한 결과 99 atom％였다. 또한, Cu/W 필름은 전기 도금하는 동안 합금 형태를 이루기 때문에 접착성도 좋았다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2001년도 하계학술대회 논문집
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• pp.578-581
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• 2001

Silicon wafers using DRAM devices required for high cleaning technology and this cleaning technology was evaluated by defect level or electron life time. This paper examined the correlation of SPV(Surface Photo Voltaic Analyzer) which analyzes diffusion length of minority carriers and DLTS(Deep level Transient Spectroscope) which analyzes defect level.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1989년도 추계학술대회 논문집 학회본부
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• pp.149-150
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• 1989

Diamond thin films were synthesised from the mixed gases of $CH_4$ and $H_2$ on silicon substrate by R.F plasma CVD and films deposited were investigated by SEM. XRD and Raman spectroscope. From these result, cubo-octahedral diamond particles were synthesised under the following condition: methane concentration. 1.0vol% ; pressure of reactor, 0.3torr ; R.F power, 500W ; reaction time, 20hr.

• 대한치과보철학회지
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• 제45권1호
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• pp.71-84
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• 2007

Statement of problem: Implant surface characteristics plays an important role in clinical success and many studies have been made for improvement of success by changing surface roughness. Purpose: Appropriate increase of surface roughness increases the activity of osteoblast and enhance contact and retention between bone and implant. Material and method- Machined, SLA and RBM surface implants, which are the most commonly used implants were implanted into the tibia of rabbits and after 1 week, 4 weeks, 8 weeks and 12 weeks there were histologic and histomorphometric analysis and study for bone gradient and change of Ca/P ratio using EDS(Energy Dispersive X-ray Spectroscope). Results: Comparison of bone-implant contact showed no significant difference among each implant. In comparison of bone area rates, SLA showed higher value with significant difference at 1 week and 4 weeks, and SLA and RBM at 8 weeks than Machined implant (p<0.05). In analysis of bone constituents with EDS, titanium was specifically detected in new bones and the rates were constant by surface treatment method or period. In case of Ca/P ratio, according to surface treatment method, each group showed significant difference. Lots of old bone fragments produced during implantation remained on the rough surface of RBM implant surface and each group showed histological finding with active synthesis of collagen fibers until 12 weeks. In transmission electronic microscopic examination of sample slice after elapse of twelve weeks, tens nm of borderline (lamina limitans like dense line)was seen to contact the bone, on the interface between bone and implant. Conclusion: SLA and RBM implant with rough surface shows better histomorphometrical result and the trend of prolonged bone formation and maturation in comparison with Machined implant. In addition, implant with rough surface seems to be helpful in early stage bone formation due to remaining of old bone fragments produced in implantation. From the results above, it is considered to be better to use implant with rough surface in implantation.