• Transactions on Electrical and Electronic Materials
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• v.9 no.1
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• pp.28-32
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• 2008

Hydrogenated microcrystalline silicon(${\mu}c$-Si:H) films were prepared using inductively coupled plasma chemical vapor deposition(ICP-CVD) method, electrical and optical properties of these films were studied as a function of silane concentration. And then, effect of $PH_3\;and\;B_2H_6$ addition on their electrical properties was also investigated for solar cell application. Characterization of these films from X-ray diffraction revealed that the conductive film exists in microcrystalline phase embedded in an amorphous network. At $PH_3/SiH_4$ gas ratio of $0.9{\times}10^{-3}$, dark conductivity has a maximum value of ${\sim}18.5S/cm$ and optical bandgap also a maximum value of ${\sim}2.39eV$. Boron-doped ${\mu}c$-Si:H films, satisfied with p-layer of solar cell, could be obtained at ${\sim}10^{-2}\;of\;B_2H_6/SiH_4$.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.1
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• pp.132-138
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• 2007

Carbon nanotubes (CNTs) arc grown on Ni catalysts employing an inductively-coupled plasma chemical vapor deposition (ICP-CVD) method. The structural and field-emissive properties of the CNTs grown are characterized in terms of the substrate-bias applied. Characterization using the various techniques, such as field-omission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Auger spectroscopy (AES), and Raman spectroscopy, shows that the structural properties of the CNTs, including their physical dimensions and crystal qualities, as well as the nature of vertical growth, are strongly dependent upon the application of substrate bias during CNT growth. It is for the first time observed that the provailing growth mechanism of CNTs, which is either due to tip-driven growth or based-on-catalyst growth, may be influenced by substrate biasing. It is also seen that negatively substrate-biasing would promote the vertical-alignment of the CNTs grown, compared to positively substrate-biasing. However, the CNTs grown under the positively-biased condition display a higher electron-emission capability than those grown under the negatively-biased condition or without any bias applied.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.4
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• pp.55-60
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• 2002

This paper presents a technique for the preparation of vertically grown CNTs by ICPHFCVD(inductively coupled plasma hot filament chemical vapor deposition) below $580^{\circ}C$. Purification of the CNTs(carbon nanotubes) using RE(radio frequency) plasma in a one step process, based on the different etching property of the Ni-tip, amorphous carbon and carbonaceous materials is also discussed. After purifying the grown materials. CNTs shown the multi walled and hollow typed structure. The typical outer and inner diameters or CNT were 50 nm and 25 nm, respectively. The graphitic wall was composed of 82 layers and the distance between wall and wall was 0.34 nm. From the results of TEM observation, the Ni catalyst at the tip of the carbon nanotubes were effectively removed by using a RF plasma etching, continuously.

• Proceedings of the Materials Research Society of Korea Conference
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• 2011.10a
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• pp.16.2-16.2
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• 2011

Graphene has attracted significant attention due to its unique characteristics and promising nanoelectronic device applications. For practical device applications, it is essential to synthesize high-quality and large-area graphene films. Graphene has been synthesized by eloborated mechanical exfoliation of highly oriented pyrolytic graphite, chemical reduction of exfoliated grahene oxide, thermal decomposition of silicon carbide, and chemical vapor deposition (CVD) on metal substrates such as Ni, Cu, Ru etc. The CVD has advantages over some of other methods in terms of mass production on large-areas substrates and it can be easily separated from the metal substrate and transferred to other desired substrates. Especially, plasma-enhanced CVD (PECVD) can be very efficient to synthesize high-quality graphene. Little information is available on the synthesis of graphene by PECVD even though PECVD has been demonstrated to be successful in synthesizing various carbon nanostructures such as carbon nanotubes and nanosheets. In this study, we synthesized graphene on $Ni/SiO_2/Si$ and Cu plate substrates with CH4 diluted in $Ar/H_2$ (10%) by using an inductively-coupled PECVD (ICPCVD). High-quality graphene was synthesized at as low as $700^{\circ}C$ with 600 W of plasma power while graphene layer was not formed without plasma. The growth rate of graphene was so fast that graphene films fully covered on substrate surface just for few seconds $CH_4$ gas supply. The transferred graphene films on glass substrates has a transmittance at 550 nm is higher 94%, indicating 1~3 monolayers of graphene were formed. FETs based on the grapheme films transferred to $Si/SiO_2$ substrates revealed a p-type. We will further discuss the synthesis of graphene and doped graphene by ICPVCD and their characteristics.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.50 no.2
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• pp.49-56
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• 2001

Diamond thin films have been deposited on the silicon substrate by inductively coupled radio frequency plasma enhanced chemical vapor deposition system. The morphological features of thin films depending on methane concentration and deposition time have been studied by scanning electron microscopy and Raman spectroscopy. The diamond particles deposited uniformly on silicon substrate($10{\times}10[mm^2]$) at the pressure of 1[torr], a methane concentration of 1[%], a hydrogen flow rate of 60[sccm], a substrate temperature of $840\{sim}870[^{\circ}C]$, an input power of 1[kw], and a deposition time of 1[hour]. With increasing deposition time, the diamond particles grew, and than about 3 hours have passed, the graphitic phase carbon thin film with "cauliflower-like" morphology deposited on the diamond thin films.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.10a
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• pp.54-54
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• 2003

DLC films were deposited on Si(100) substrates by inductively coupled plasma (ICP) assisted chemical vapor deposition (CVD). A mixture of acetylene (C$_2$H$_2$) and argon (Ar) gases was used as the precursor and plasma source, respectively. The structure of the films was characterized by the Raman spectroscopy. Results from the Raman spectroscopy analysis indicated that the property change of the DLC films is due to the sp$^3$ and sp$^2$ ratio in the films under various conditions such as ICP power, working pressure and RF substrate bias. The hydrogen content in the DLC films was determined by an electron recoil detector (ERB). The roughness of the films was measured by atomic force microscope (Am). A microhardness tester was used for the hardness and elastic modulus measurement. The DLC film showed a maximum hardness of 37㎬. In this work, the relationship between deposition parameters and mechanical properties were discussed.

• Journal of the Semiconductor & Display Technology
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• v.8 no.4
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• pp.65-69
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• 2009

Carbon nanotubes (CNTs) were coated with undoped zinc oxide (ZnO) or 5 wt% gallium-incorporated ZnO (GZO) using various deposition conditions. The CNTs were directly grown on conical-type tungsten substrates at $700^{\circ}C$ using inductively coupled plasma-chemical vapor deposition. The pulsed laser deposition technique was used to deposit the ZnO and GZO thin films with very low stress. Field-emission scanning electron microscopy and high-resolution transmission electron microscopy were used to monitor the variations in the morphology and microstructure of CNTs prior to and after ZnO or GZO coating. The formation of ZnO and GZO films on CNTs was confirmed using energy-dispersive x-ray spectroscopy. In comparison to the as-grown (uncoated) CNT emitter, the CNT emitter that was coated with a thin (10 nm) GZO film showed remarkably improved field emission characteristics, such as the emission current of $325\;{\mu}A$ at 1 kV and the threshold field of $1.96\;V/{\mu}m$ at $0.1\;{\mu}A$, and it also exhibited the highly stable operation of emission current up to 40 h.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2007.04a
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• pp.87-88
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• 2007

나노 다결정 실리콘 박막 증착을 하기 위해서 현재 정전결합플라즈마(CCP, Capacitively Coupled Plasma)를 이용한 PECVD(Plasma Enhanced Chemical Vapor Deposition) 공정에 관한 여구가 활발히 이루어지고 있다. 유도결합플라즈마는(ICP, Inductively Coupled Plasma) 정전결합플라즈마보다 플라즈마 밀도가 높고 파워전달 효율이 좋은 것으로 알려져 있으나 대면적가 어려워 기판이 큰 TFT-LCD로는 많이 연구되고 있지 않다. 본 연구는 유도결합플라즈마를 위해 내장형 multiple U-type 선형 안테나를 이용하여 나노 다결정 실리콘 박막을 증착하여 그 특성을 분석하였다.

• 한국정보디스플레이학회:학술대회논문집
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• 2003.07a
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• pp.1127-1130
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• 2003

The characteristics of silicon nitride films deposited in a planar coil reactor using a simple high-density inductively coupled plasma chemical vapor deposition technique have been investigated. The process gases used during silicon nitride deposition cycle were pure nitrogen and a mixture of silane and helium. It has been pointed out that the strong H-atom released from the growing SiN film and Si-N bond healing are responsible for the improved electrical and passivation properties of SiN.

• Proceedings of the Korean Vacuum Society Conference
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• 2000.02a
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• pp.98-98
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• 2000

초고집적(ULSI) 반도체 소자의 multilevel metalization을 위한 중간 유저네로서 저 유전상수(k<)와 높은 열적안정성(>45$0^{\circ}C$)을 갖는 새로운 물질을 도입하는 것이 필요하다. 중합체 박막은 낮은 유전상수와 높은 열적 안정성으로 인하여 low-k 물질로 적당하다고 여겨진다. PECVD에 의한 plasma polymer 박막의 증착은 많이 보고되어 왔으마 고밀도 플라즈마 형성이 가능하고 기판으로 유입되는 ion의 energy 조절이 가능한 inductively coupled plasma(ICP) CVD에 의한 plasma polymer 박막에 대한 연구는 보고된 바 없다. 본 연구에서는 Mtehyl-cyclohexane precusor를 사용하여 substrate에 bias를 주면서 inductively coupled plasma(ICP)를 이용하여 플라즈마 폴리머 박막(plasma polymerized methyl-cyclohexane : 이하^g , pp MCH라 칭함)을 증착하였으며 ICP power와 substrate bias(SB) power가 증착된 박막의 특성에 어떠한 영향을 미치는지 알아보았다. 증착된 박막의 유전상 수 및 열적 안정성은 ICP power의 변화에 비해 SB power의 변화에 더 크게 영향을 받았다.^g , pp MCH 박막은 platinum(Pt) 기판과 silicon 기판위에서 같이 증착되었다. Methyl-cyclohexane precursor는 4$0^{\circ}C$로 유지된 bubbler에 담겨지고 carrier 가스 (H2:10%, He:90%)에 의해 reactor 내부로 유입된다.^g , pp MCH 박막은 증착압력 350 mTorr, 증착온도 6$0^{\circ}C$에서 \circled1SB power를 10W에 고정시키고 ICP power를 5W부터 70W까지, \circled2ICP power를 10W에 고정시키고 SB power를 5W부터 70W까지 변화하면서 증착하였다. 유전 상수 및 절연성은 Al/PPMCH//Pt 구조의 capacitor를 만들어서 측정하였으며, 열적 안정성은 Ar 분위기에서 30분간의 열처리 전후의 두께 변화를 측정함으로써 분석하였다. SB power 10W에서 ICP power가 5W에서 70w로 증가함에 따라 유전상수는 2.65에서 3.14로 증가하였다. 열적 안정성은 ICP power의 증가에 따라서는 크게 향상되지 않은 것으로 나타났다. ICP power 10W에서 SB power가 5W에서 70W로 증가함에 따라 유전상수는 2.63에서 3.46으로 증가하였다. 열적 안정성은 SB power의 증가에 따라 현저하게 향상되었으며 30W 이상에서 증착된 박막은 45$0^{\circ}C$까지 안정하였고, 70W에서 증착된 박막은 50$0^{\circ}C$까지 안정하였다. 열적 안정성은 ICP power의 증가에 따라서는 현저하게 향상되었다. 그 원인은 SB power의 인가에 의해 활성화된 precursor 분자들이 큰 에너지를 가지고 기판에 유입되어 치밀한 박막이 형성되었기 때문으로 사료된다.