• 한국표면공학회지
• /
• 제46권2호
• /
• pp.61-67
• /
• 2013

Thin film solar cells have attracted much attention due to their high cell efficiency, comparatively low process cost, and applicability to flexible substrates. In particular, CIGS solar cells have been widely studied and produced because they demonstrated the highest cell efficiency. However, the deposition process of CIGS films generally includes the selenization process conducted at elevated temperature using toxic $H_2Se$ gas. To avoid this selenization process, CIGS thin films were, in this study, deposited by RF sputtering using single composite CIGS target. In addition, the effects of sputtering bias voltage and heat treatment on the microstructural and morphological changes in deposited CIGS films were investigated and discussed.

• 한국표면공학회지
• /
• 제54권5호
• /
• pp.285-293
• /
• 2021

High-entropy TiAlCrSiN nano-composite coating was designed to improve mold life for high temperature liquid molding. Alloy design, powder fabrication and single alloying target fabrication for the high-entropy nano-composite coating were carried out. Using the single alloying target, an arc ion plating method was applied to prepare a TiAlCrSiN nano-composite coating had a 30 nm TiAlCrSiN layers are deposited layer by layer, and form about 4 ㎛-thickness of multi-layered coating. TiAlCrSiN nano-composite coating had a high hardness of about 39.9 GPa and a low coefficient of friction of less than about 0.47 in a dry environment. In addition, there was no change in the structure of the coating after the dissolution loss test in the molten metal at a temperature of about 1100 degrees.

• 한국재료학회지
• /
• 제1권4호
• /
• pp.191-197
• /
• 1991

Composite $TiSi_{2.6}$ target으로 부터 Ti-silicide를 형성시 단결정 Si기판과 다결정 Si내의 dopant의 확산 거동, 그리고 Ti-silicide 박막의 표면 거칠기를 secondary ion mass spectrometry (SIMS), 4-point probe, X-선 회절 분석, 표면 거칠기 측정을 통해 조사하였다. X-선 회절 분석결과 중착된 직후의 중착막은 비정질이었고, 단결정 Si기판에 증착된 막은 $800^{\circ}C$에서 20초간 급속 열처리 시 orthorhombic $TiSi_2$(C54 구조)로 결정화가 이루어졌다. 단결정 Si 기판과 다결정 Si에서 Ti-silicide 충으로의 dopant의내부 확산은 거의 발생하지 않았으며, 주입된 불순물들은 Ti-silicide/Si 계면 근처의 단결정 Si이나 다결정 Si 내부에 존재하고 있었다. 또한 형성된 Ti-silicide 박막의 표면 거칠기는 16-22nm이었다.

• 한국전기전자재료학회논문지
• /
• 제29권10호
• /
• pp.665-670
• /
• 2016

Prevailing dissemination of machine tools and cutting technology have caused drastic developments of high speed dry machining with work materials of high hardness, and demands on the high-hardness-materials with high efficiency have become increasingly important in terms of productivity, cost reduction, as well as environment-friendly issue. Addition of Si to TiAlN has been known to form nano-composite coating with higher hardness of over 30 GPa and oxidation temperature over $1,000^{\circ}C$. However, it is not easy to add Si to TiAlN by using conventional PVD technologies. Therefore, Ti-Al-Si-N have been prepared by hybrid process of PVD with multiple target sources or PVD combined with PECVD of Si source gas. In this study, a single composite target of Ti-Al-Si was prepared by powder metallurgy of MA (mechanical alloying) and SPS (spark plasma sintering). Properties of he resulting alloying targets were examined. They revealed a microstructure with micro-sized grain of about $1{\sim}5{\mu}m$, and all the elements were distributed homogeneously in the alloying target. Hardness of the Ti-Al-Si-N target was about 1,127 Hv. Thin films of Ti-Al-Si-N were prepared by unbalanced magnetron sputtering method by using the home-made Ti-Al-Si alloying target. Composition of the resulting thin film of Ti-Al-Si-N was almost the same with that of the target. The thin film of Ti-Al-Si-N showed a hardness of 35 GPa and friction coefficient of 0.66.

• 한국방사선학회논문지
• /
• 제14권3호
• /
• pp.193-201
• /
• 2020

본 연구 목적은 선형가속기를 통해 입사된 전자가 표적(target)을 구성하는 물질과 두께에 따른 광자 특성을 평가하는 것이다. 전산모사 설계는 2 mm 두께의 텅스텐 단일물질과 1.8 mm 와 2.3 mm 두께의 텅스텐과 구리 복합물질로 구성된 선형가속기 표적(Target)이다. 연구 방법은 첫째, 표적 내 일차 입자의 거동은 전자플루언스와 전자 에너지 축적으로 평가하였다. 둘째, 표적 내에서 발생하는 광자는 광자 플루언스로 평가하였다. 셋째, 표적으로부터 1 m 거리에서의 광자 각-에너지 분포는 광자 플루언스로 평가하였다. 그 결과 첫째, 단일물질과 복합물질 표적에서의 전자 플루언스와 에너지 축적을 통해 일차 입자인 전자가 표적 밖으로 방출되지 않았으며, 표적 두께에 따라 전자가 음의 선형적으로 감쇄하였다. 둘째, 복합물질 표적이 단일물질 표적보다 광자 생성이 더 높은 것으로 나타났다. 이는 물질 구성 성분과 두께가 광자 생성에 영향을 준다는 사실을 확인하였다. 셋째, 차폐 해석에 필요한 각 분포에 따른 광자 플루언스를 계산하였다. 이러한 결과는 선형가속기 표적을 구성하는 물질과 두께에 따라 광자 생성률이 차이 나는 것을 확인할 수 있었다. 따라서, 본 연구는 국가에서 도입 중인 컨테이너 보안 검색용 선형가속기 사용시설의 설계 및 운영 시 필요한 자료이며, 방사선 방호에 기초 자료로 활용될 수 있을 것으로 생각된다.

• 한국표면공학회:학술대회논문집
• /
• 한국표면공학회 2017년도 춘계학술대회 논문집
• /
• pp.95.1-95.1
• /
• 2017

In this study, it has been tried to make the single Mo-Cu alloying targets with the Cu showing the best surface hardness that was determined by investigation on the coatings with the double target process. The single alloying targets were prepared by powder metallurgy methods such as mechanical alloying and spark plasma sintering. The nanocomposite coatings were prepared by reactive magnetron sputtering process with the single alloying targets in $Ar+N_2$ atmosphere. The microstructure changes of the Mo-Cu-N coatings with diverse Cu contents were investigated by using XRD, SEM and EDS. The mechanical properties of the coatings were evaluated by using nano-indentor, scratch test, and ball on disc methods. Especially, the coated samples were tested by using various lubricating oil to compare the property of anti wear-resistance. In this study, the nano-composite MoN-Cu coatings prepared using an alloying target was eventually compared with the coatings from the multiple targets.

• 분석과학
• /
• 제5권2호
• /
• pp.199-202
• /
• 1992

$BF_2$를 50keV, 90keV로 에너지를 달리하여 주입한 실리콘 기판에 타이타늄을 sputter하여 Ti-slicide를 형성한 시편과 composite target을 사용하여 Ti-silicide를 형성한 시편을 준비하였다. Ti-silicide 형성시 boron의 거동을 SIMS(secondary ion mass spectrometry)로 분석하였다. Metal-Ti target을 사용한 경우 Ti-silicide 형성시 불순물들이 재분포하였으며 이온 주입 에너지가 작은 경우 심한 out-diffusion이 발생하였다. 한편 Composite target을 사용한 경우 거의 재분포가 발생하지 않고 안정된 boron의 분포를 보였다.

• 한국표면공학회지
• /
• 제49권4호
• /
• pp.368-375
• /
• 2016

MoN-Cu thin films were prepared to achieve appropriate properties of high hardness and low friction coefficient, which could be applied to automobile engine parts for reducing energy consumption as well as solving wear problems. Composite thin films of MoN-Cu have been deposited by various processes using multiple targets such as Mo and Cu. However, those deposition with multiple targets revealed demerits such as difficulties in exact control of composition and homogeneous deposition. This study is aiming for suggesting an appropriate process to solve those problems. A single alloying target of Mo-Cu (10 at%) was prepared by powder metallurgy methods of mechanical alloying (MA) and spar plasma sintering (SPS). Thin film of MoN-Cu was then deposited by magnetron sputtering using the single alloying target of Mo-Cu (10 at%). Properties of the resulting MoN-Cu thin film were examined and compared to those of MoN-Cu thin films prepared with double targets of Mo and Cu.

• Nuclear Engineering and Technology
• /
• 제55권6호
• /
• pp.1994-1998
• /
• 2023

This study quantitatively evaluated the source term of a linear accelerator according to target thickness for a 6-20 MeV electron beam using MCNP6. The elements of the target were tungsten and copper, and a composite target and single target were simulated by setting different thickness parameters depending on energy. The accumulation of energy generated through interaction with the collided target was evaluated at 0.1-mm intervals, and F6 tally was used. The results indicated that less than 3% reference error was maintained according to the MCNP recommendations. At 6, 8, 10, 15, 18, and 20 MeV, the energy accumulation peaks identified for each target were 0.3 mm in tungsten, 1.3 mm in copper, 1.5 mm in copper, 0.5 mm in tungsten, 0.5 mm in tungsten, and 0.5 mm in tungsten. For 8 and 10 MeV in a single target consisting only of copper, the movement of electrons was confirmed at the end of the target, and the proportion of escaped electrons was 0.00011% and 0.00181%, respectively.

• 한국진공학회:학술대회논문집
• /
• 한국진공학회 2000년도 제18회 학술발표회 논문개요집
• /
• pp.213-213
• /
• 2000

Direct laser vaporization of transition-metal(Co, Ni)/graphite composite pellet produced single wall carbon naotubes(SWNT) in the condensing vapor in a heated flow cylinder-type tube furnace, Transition metal/graphite composite pellet target was made by mixing graphite, Co, and Ni in 98:1:1 atomic weight ratios, pressing the mixed powder, and curing it. The target was placed in a tube furnace maintained at 1200$^{\circ}C$ and Ar inert collision gas continuously flowed into the tube. The 2nd harmonic, 532nm wavelength light from Nd-YAG laser was used to vaporize the tube. The carbon nanotubes produced by the laser vaporization were accumulated on quartz tube wall. The raw carbon nanotube materials were purified with surfactants(Triton X-100) in a ultrasonicator. These carbon nanotubes were analyzed using SEM, XRD, and Raman spectroscopic method. The carbon nanotube growth on the Ni-patterned Si substrate was investigated by the CVD process. Transition-metal, Ni and CH4 gas were used as a catalyst and a reactant gas, respectively. The structure and the phonon frequencies of the carbon nanotubes formed on the patterned Si substrate were measured by SEM and Raman spectrometer.