• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.11a
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• pp.92-92
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• 2008

The surface flatness of heteroepitaxially grown 3C-SiC thin films is a key factor affecting electronic and mechanical device applications. This paper describes the surface flatness of polycrystalline 3C-SiC thin films by the gas flow control according to the location change of geometric structure. The polycrystalline 3C-SiC thin film was deposited by APCVD(Atmospheric pressure chemical vapor deposition) at $1200^{\circ}C$ using HMDS(Hexamethyildisilane : $Si_2(CH_3)_6)$ as single precursor, and 5 slm Ar as the main flow gas. According to the location of geometric structure, surface fringes and flatness changed. It shows the distribution of thickness is formed uniformly in the specific location of the geometric structure.

• Journal of the Korean Vacuum Society
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• v.5 no.1
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• pp.77-84
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• 1996

Silicon deposition by Penning discharge was carried out using a mixture of 5% $SiH_4/H_2$ and Ar gas, and the effects of the deposition conditions(gas mixing raito, substrate temperature. discharge power etc.) on the growth rate, crystallinity and morphology of the films deposited were investigated. The magnetic field(800 G) confined the plasma in the region between the two cathodes and enhanced the discharge current by a factor of a few hundreds below 1 mTorr. The magnetic field-enhanced plasma density resulted in a very large deposition rate of about 300 $\AA$/min at $SiH_4$ flow rate of 0.7 sccm and the substrate temperature of $800^{\circ}C$. Characterization of the films by Raman spectroscopy, X-ray diffraction, and scanning electron microscopy revealed that an epitaxial film with a smooth surface grows above 80$0^{\circ}C$, an amorphous film below $400^{\circ}C$, and a rough polycrystalline film at intermediate temperatures.

• Journal of the Korean Ceramic Society
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• v.41 no.3
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• pp.247-252
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• 2004

노튜브의 길이는 급격히 증가하였지만 촉매금속의 적층방법에 따른 탄소나노튜브의 성장 형태는 큰 차이가 없었다. 특히, ICBD 방법에 의해 Ni 촉매금속을 증착한 경우 다른 방법에 비하여 직선적인 탄소나노튜브가 관찰되었다. ^x Carbon nanotubes were grown on SiO$_2$/Si substrates by applying $C_2$H$_2$ gas through chemical vapor deposition process. It was found that carbon nanotubes were grown successfully on the substrates with catalytic films under 20 $\AA$ total thickness. The increase in reaction temperature from 50$0^{\circ}C$ to 80$0^{\circ}C$ resulted in longer carbon nanotube, but there was no clear tendencies with different types of catalytic layers. It was evident that carbon nanotubes became more straight on the substrate with Ni catalytic film produced by ICBD method.

• Proceedings of the KIEE Conference
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• 1997.11a
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• pp.317-319
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• 1997

We have studied the properties of $GaAs_{1-x}P_x$ epitaxial films on the GaP using VPE method by CVD. The surface carrier concentration and PL power increased with increasing the epitaxial temperature while PL wave length decreased. The Power out of the LED with $GaAs_{1-x}P_x$/GaP structure decreased with increasing the epitaxial temperature while the forward voltage of the LED increased. Specially, The LED of $GaAs_{1-x}P_x$/GaP structure represents good electrical and optical properties when the $GaAs_{1-x}P_x$ layer was epitaxially grown at $810^{\circ}C$.

• Proceedings of the KIEE Conference
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• 1999.11d
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• pp.870-872
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• 1999

The particles were deposited on silicon wafers at low pressure:1[torr] from $CH_4-H_2$ mixed gas by using RF plasma CVD, and were investigated by SEM and Raman spectroscopy. The results are as following; Diamond particles were synthesized under $CH_4/H_2$ concentration of 1[%], however amorphous cabon particles were synthesized over $CH_4/H_2$ concentration of 2[%]. Growth rate of diamond particle was 2.2 times: $0.8[{\mu}m/h]$ as much as that synthesized at 25[torr].

• Journal of the Korean Vacuum Society
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• v.1 no.1
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• pp.212-222
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• 1992

To use polycrystalline Si Thin Film Transistor (poly-Si TFT) in high density SRAM instead of High Load Resistor (HLR), TFT is needed to show good electrical characteristics such as large carrier mobility, low leakage current, high driver current and low subthreshold swing. To satisfy these electrical characteristics, the trap state density must be reduced in the channel poly. Technological issues pertinent to the channel poly fabrication process are investigated and discussed. They are solid phase growth (SPG), Si-ion implantation, laser annealing and hydrogenation. The electrical properties of several CVD oxides used as the gate oxide of TFT are compared. The dependence of the electrical characteristics of TFT on source-drain ion-implantation dose, drain offset length and dopant lateral diffusion are also described.

• 한국정보디스플레이학회:학술대회논문집
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• 2000.01a
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• pp.137-138
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• 2000

We synthesized highly aligned carbon nanotubes by thermal decomposition of acetylene gas using metal catalyst island. The alignment technique in this experiment is a very efficient method because it does not require any treatments before and after catalyst metal deposition. Alignment of nanotubes was dominated by the uniform diameter and the high density of metal catalysts. In the field emission test, the uniform emission spots on phosphor screen were obtained from the nanotubes in spite of non-aligned tube nature.

• Bulletin of the Korean Chemical Society
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• v.24 no.12
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• pp.1771-1774
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• 2003

CNTs have been synthesized by catalytic $C_2H_2$ decomposition through $Pd/Al_2O_3$ at low temperature. The CNTs were grown to a length of about 10 ${\mu}$m and diameter 150-200 nm with multiwalled structure. Pd catalysts have two major roles; one is the active catalyst for $C_2H_2$ decomposition, the other is a nucleation site of CNT's growth.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.373-376
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• 1997

Diamond thin films were deposited on P-type(100) Si wafers using MPECVD. Prior to deposition, mechanical scretching was done to improve density of nucleation sites with diamond paste of 0.25${\mu}{\textrm}{m}$ size. Diamond films were deposited under the following conditions : methane concentration of 0.5~5%, oxygen concentration of 0~70%, process pressure of 70Torr, process temperature of 900~95$0^{\circ}C$, and deposition time 5hrs. The changes of the morphology and the growth rates of the deposits with the experimental conditions are expriend by Scanning Electron Microscopy. Raman Spectroscopy and X-ray Diffraction method.

• Journal of the Korean institute of surface engineering
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• v.29 no.5
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• pp.357-362
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• 1996

Several applications of radio-frequency (RF) thermal plasma to film formation are reviewed. Three types of injection plasma processing (IPP) technique are first introduced for the deposition of materials. Those are thermal plasma chemical vapor deposition (CVD), plasma flash evaporation, and plasma spraying. Radio-frequency (RF) plasma and hybrid (combination of RF and direct current(DC)) plasma are next introduced as promising thermal plasma sources in the IPP technique. Experimental data for three kinds of processing are demonstrated mainly based on our recent researches of depositions of functional materials, such as high temperature semiconductor SiC and diamond, ionic conductor $ZrO_2-Y_2O_3$ and high critical temperature superconductor $YBa_2Cu_3O_7-x$. Special emphasis is given to thermal plasma flash evaporation, in which nanometer-scaled clusters generated in plasma flame play important roles as nanometer-scaled clusters as deposition species. A novel epitaxial growth mechanism from the "hot" clusters namely "hot cluster epitaxy (HCE)" is proposed.)" is proposed.osed.