• JSTS:Journal of Semiconductor Technology and Science
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• v.5 no.3
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• pp.182-186
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• 2005

In this work, thermal evaporation system was employed to deposit thin films of SiC on glass substrates in order to determine the parameters of them. Measurements included transmission, absorption, Seebak effect, resistivity and conductivity, absorption coefficient, type of energy band-gap, extinction coefficient as functions of photon energy and the effect of increasing film thickness on transmittance. Results explained that SiC thin film is an n-type semiconductor of indirect energy band-gap of ${\sim}3eV$, cut-off wavelength of 448nm, absorption coefficient of $3.4395{\times}10^{4}cm^{-1}$ and extinction coefficient of 0.154. The experimental measured values are in good agreement with the typical values of SiC thin films prepared by other advanced deposition techniques.

• Tribology and Lubricants
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• v.19 no.2
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• pp.109-115
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• 2003

Nanotribological characteristics between a Si$_3$N$_4$ AFM tip and hydrophobic thin films were experimentally studied. Tests were performed to measure the nano adhesion and friction in both AFM (atomic force microscope) and LFM (lateral force microscope) modes in various .ranges of normal load. Plasma-modified thin polymeric films were deposited on Si-wafer (100). Results showed that wetting angle of plasma-modified thin polymeric film increased with the treating time, which resulted in the hydrophobic surface and the decrease of adhesion and friction. Nanotribological characteristics of these surfaces were compared with those of other hydrophobic surfaces, such as DLC, OTS and IBAD-Ag coated surfaces. Those of OTS coated surface were superior to those of others, though wetting angle of plasma-modified thin polymeric film is higher.

• Proceedings of the KIEE Conference
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• 1997.07d
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• pp.1229-1231
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• 1997

In this work, PZT(20/80)/(80/20) heterolayered thin film that has the tetragonal and rhombohedral structure was fabricated by Sol-Gel method spin-coated on the Pt/Ti/$SiO_2$/Si substrate by turns. The thickness of PZT-1 film obtained by six-times of drying/sintering process was about 480[nm]. This procedure was repeated several times to form PZT heterolayered thim film. PZT-5 thin films with top layer of tetragonal PZT(20/80) thin film showed dense grain structure and PZT-6 thin film with top layer of rhombohedral PZT(80/20) thin film showed the microstructure without rosette. Dielectric constant increased with increasing the number of coatings, and it was about 13S5 at PZT-6 thin film. Dielectric loss was not depend on the number of coatings.

• Journal of IKEEE
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• v.21 no.1
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• pp.85-88
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• 2017

This study focused on the development of in-situ passivation system and characterization of OLED display. The thin film passivation process with thin film layers was investigated using in-situ passivation technique in the cluster system. Thin films of $SiO_2$, SiNx passivation were manufactured using PECVD, which enables the deposition process at room temperature. The cluster system was created to develop in-situ passivation process, which OLED and thin film were fabricated in the cluster system without exposing to the atmospheric environment. It is expected that the in-situ passivation system of OLED with organic and inorganic layer provides the leading technique to develop flexible OLED.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.11a
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• pp.45-45
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• 2009

This paper describes the formation of porous 3C-SiC by anodization. 3C-SiC thin films were deposited on p-type Si(100) substrates by APCVD using HMDS (Hexamethyildisilane: $Si_2(CH_3)_6$). UV-LED(380 nm) was used as a light source. The surface morphology was observed by SEM and the pore size was increased with increase of current density. Pore diameter of 70 ~ 90 nm was achieved at 7.1 $mA/cm^2$ current density and 90 sec anodization time. FT-IR was conducted for chemical bonding of thin film and porous 3C-SiC. The Si-H bonding was observed in porous 3C-SiC around wavenumber 2100 $cm^{-1}$. PL shows the band gap enegry of thin film (2.5 eV) and porous 3C-SiC (2.7 eV).

• 한국정보디스플레이학회:학술대회논문집
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• 2004.08a
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• pp.957-961
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• 2004

In order to realize high performance thin film transistor (TFT) on plastic substrate, Si film was deposited on plastic substrate at 170$^{\circ}C$ by using inductivity coupled plasma chemical vapor deposition (ICPCVD). Hydrogen concentration in as-deposited Si film was 3.8% which is much lower than that in film prepared by using conventional plasma enhanced chemical vapor deposition (PECVD). Si film was deposited as micro crystalline phase rather than amorphous phase even at 170$^{\circ}C$ because of high density plasma. By step-by-step Excimer laser annealing, dehydrogenation and recrystallization of Si film were carried out simultaneously. With step-by-step annealing and optimization of underlayer structure, it has succeeded to achieve large grain size of 300nm by using ICPCVD. Base on these results, poly-Si TFT was fabricated on plastic substrate successfully, and it is sufficient to drive pixels of OLEDs, as well as LCDs.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.29 no.8
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• pp.505-509
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• 2016

We have investigated the characteristics of amorphous silicon (a-Si) thin-film solar cell by inserting barrier layer. The conversion efficiency of a-Si thin-film solar cells on graphite substrate shows nearly zero because of the surface roughness of the graphite substrate. To enhance the performance of solar cells, the surface morphology of the back side were modified by changing the barrier layer on graphite. The surface roughness of graphite substrate with the barrier layer grown by plasma enhanced chemical vapor deposition (PECVD) reduced from ~2 um to ~75 nm. In this study, the combination of the barrier layer on graphite substrate is important to increase solar cell efficiency. We achieved ~ 7.8% cell efficiency for an a-Si thin-film solar cell on graphite substrate with SiNx/SiOx stack barrier layer.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.22 no.6
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• pp.462-465
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• 2009

Schottky barrier thin film transistors (SB-TFT) on polycrystalline silicon(poly-Si) are fabricated by platinum silicided source/drain for p-type SB-TFT. High quality poly-Si film were obtained by crystallizing the amorphous Si film with excimer laser annealing (ELA) or solid phase crystallization (SPC) method, The fabricated poly-Si SB-TFTs showed low leakage current level and a large on/off current ratio larger than 10), Significant improvement of electrical characteristics were obtained by the additional forming gas annealing in 2% $H_2/N_2$ ambient, which is attributed to the termination of dangling bond at the poly-Si grain boundaries as well as the reduction of interface trap states at gate oxide/poly-Si channel.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.11a
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• pp.311-312
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• 2005

By using 45$^{\circ}$ obliqued evaporation method with electron beam system, uniformly vertical liquid crystal (LC) alignment was achieved. And a high pretilt angles of about 2.5$^{\circ}$ were measured. Also, it was verified that there are no variations of pretilt angle as a function of $SiO_x$ thin film thickness 20nm and 50nm. A good LC alignment states were observed at annealing temperature of 250$^{\circ}C$. The high pretilt angle and the good thermal stability of LC alignment by 45$^{\circ}$ obliqued electron beam evaporation method on the $SiO_x$ thin film can be achieved.

• Proceedings of the Korean Vacuum Society Conference
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• 2014.02a
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• pp.303.2-303.2
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• 2014

The oxides of group IV transition metals such as titanium, zirconium, hafnium have many important current and future application, including protective coatings, sensors and dielectric layers in thin film electroluminescent (TFEL) devices. Recently, group IV transition metal oxide films have been intensively investigated as replacements for SiO2. Due to high permittivities (k~14-25) compared with SiO2 (k~3.9), large band-gaps, large band offsets and high thermodynamic stability on silicon. Herein, we report the synthesis of new group IV transition metal complexes as useful precursors to deposit their oxide thin films using chemical vapor deposition technique. The complexes were characterized by FT-IR, 1H NMR, 13C NMR and thermogravimetric analysis (TGA). Newly synthesised compounds show high volatility and thermal stability, so we are trying to deposit metal oxide thin films using the complexes by Atomic Layer Deposition (ALD).