• Korean Journal of Materials Research
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• v.6 no.8
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• pp.833-840
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• 1996

Diamond thin films were deposited on p-type (100) Si wafers using MPECVD. Prior to deposition, ultrasonic striking was done to improve density of nucleation sites with dimond powder of 40~$60\mu$m size. Then diamond thin films were deposited at $^900{\circ}C$, 40Torr and 1000W microwave power using ${CH}_{4}$ and ${H}_{2}$ gases. The purity, the morphology and the microstructur'e and microdefects of diamond thin films were characterized by Raman spectroscopy, SEM and TEM, repectively. In Raman spectroscopy the peaks of non-diamond phase increased as ${CH}_{4}$, concentration increased. In SEM, the morphology of diamond thin films varied from crystalline to cauliflower as ${CH}_{4}$, concentration increased. As ${CH}_{4}$ con centration increased, the density of defects increased, with most defects being {III} twin. ${MTP}_{5}$, were formed with five (II]) planes. As these (Ill) Planes were twinned, ${MTP}_{5}$, represented five-fold symmetry. ]n the interfaces, defects in diamond thin films fanned out from small regions implying nucleation sites.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.3
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• pp.107-112
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• 2003

Amorphous carbon nitride thin films have been deposited on silicon (100) by reactive magnetron sputtering method. The basic depositon parameters varied were the r.f. power(up to 250 W), the deposition pressure in the reactor(up to 100 mtorr) and Ar:$N_2$ gas ratio. FT-IR and X-ray photoelectron spectra showed the presence of different carbon-nitrogen bonds in the films. The surface topography of the films was studied by scanning electron microscopy(SEM) and atomic force microscopy(AFM).

• Proceedings of the Materials Research Society of Korea Conference
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• 1999.11a
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• pp.140-140
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• 1999

• Transactions of Materials Processing
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• v.29 no.1
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• pp.44-48
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• 2020

Aluminum nitride (AlN), as a substrate material in electronic packaging, has attracted considerable attention over the last few decades because of its excellent properties, which include high thermal conductivity, a coefficient of thermal expansion that matches well with that of silicon, and a moderately low dielectric constant. AlN films with c-axis orientation and thermal conductivity characteristics were deposited by using Pulsed Laser Deposition (PLD). The epitaxial AlN films were grown on sapphire (c-Al₂O₃) single crystals by PLD with AlN target and Y₂O₃ doped AlN target. A comparison of different targets associated with AlN films deposited by PLD was presented with particular emphasis on thermal conductivity properties. The quality of AlN films was found to strongly depend on the growth temperature that was exerted during deposition. AlN thin films deposited using Y₂O₃-AlN targets doped with sintering additives showed relatively higher thermal conductivity than while using pure AlN targets. AlN thin films deposited at 600℃ were confirmed to have highly c-axis orientation and thermal conductivity of 39.413 W/mK.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.13 no.7
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• pp.612-616
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• 2000

This paper describes on the fabrication and characteristics of hot-film type micro-flowsensors integrated with Pt-RTD(resistance thermometer device) and micro-heater on the Si membrane in which MgO thin-film was used as medium layer in order to improve adhesion of Pt thin-film to SiO$_2$layer. The MgO layer improved adhesion of Pt thin-film to SiO$_2$layer without any chemical reactions to Pt thin-film under high annealing temperatures. Output voltages increased due to increase of heat-loss from sensor to external. The output voltage was 82 mV at $N_2$flow rate of 2000 sccm/min heating power of 1.2 W. The response time($\tau$:63%) was about 50 msec when input flow was stepinput

• Journal of the Korean institute of surface engineering
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• v.46 no.4
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• pp.168-174
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• 2013

In this study, low-cost, high-speed deposition, excellent processability, high mechanical strength and electrical conductivity, chemical stability and corrosion resistance of stainless steel to meet the obsessive-compulsive (0.1 mm or less) were selected CrN thin film. new price reduction to sputter deposition causes - the possibility of sublimation source for inductively coupled plasma Cr rods were attempts by DC bias. 0.6 Pa Ar inductively coupled plasmas of 2.4 MHz, 500 W, keeping Cr Rod DC bias power 30 W (900 V, 0.02 A) is applied, $N_2$ flow rate of 0.5, 1.0, 1.5 sccm by varying the characteristics of were analyzed. $N_2$ flow rate increases, decreases and $Cr_2N$, CrN was found to increase. In addition to corrosion resistance and contact resistance, corrosion resistance, electrical conductivity was evaluated. corrosion current density than $N_2$ 0 sccm was sure to rise in all, $N_2$ 1 sccm at $4.390{\times}10^{-7}$ (at 0.6 V) $A{\cdot}cm^{-2}$, respectively. electrical conductivity process results when $N_2$ 1 sccm 28.8 $m{\Omega}/cm^2$ with the lowest value of the contact resistance was confirmed that came out. The OES (SQ-2000) and QMS (CPM-300) using a reactive deposition process to add $N_2$ to maintain a uniform deposition rate was confirmed that.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.367-367
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• 2008

Aluminum nitride (AlN) thin films have been deposited on Si substrate by using reactive RF magnetron sputtering method in a gas mixture of Ar and $N_2$ at different $N_2$ concentration. It was found that $N_2$ concentration was varied in the range up to 20-100%, highly c-axis oriented film can be obtained at 50% $N_2$ with full width at half maximum (FWHM) $4.5^{\circ}$. Decrease in surface roughness from 7.5 nm to 4.6 nm found to be associated with decrease in grain size, with $N_2$ concentration; however, the AlN film fabricated at 20% $N_2$ exhibited a granular type of structure with non-uniform grains. The absorption peak was observed around 675 $cm^{-1}$ in fourier transform infrared spectroscopy (FTIR). It is concluded that the AlN film deposited at $N_2$ concentration of 50% exhibited the most desirable properties for the application of high-frequency surface acoustic devices.

• Journal of the Korean Society for Heat Treatment
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• v.31 no.5
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• pp.237-243
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• 2018

In-rich InGaN epilayers were grown on (0001) sapphire substrates by radio-frequency plasma-assisted molecular beam epitaxy (RF-MBE). InGaN epilayers grown at various growth condition were observed by SEM, XRD, and RHEED. When plasma power of nitrogen increased from 290 to 350 W, surface morphology and crystal quality became worse according to more active nitrogen on the surface of InGaN at N-rich growth condition. As In composition was reduced from 89 to 71% by changing the incoming flux of In and Ga, surface morphology and crystal quality became worse. In addition, weak peaks of cubic InGaN phase was observed from InGaN layer with 71% In composition by XRD ${\Phi}$ scan measurement. When growth temperature decreased from 500 to $400^{\circ}C$, RHEED diffraction pattern was changed to be from streaky to spotty which means atomically rough surface, and spotty pattern showed cubic symmetry of InGaN clearly. XRD ${\Phi}$ scan measurement gave clear evidence that more cubic InGaN phase was formed at low growth temperature. All these results indicates that extremely low surface mobility of Ga adatom caused inferior crystal quality and cubic InGaN phase.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.23 no.5
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• pp.397-402
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• 2010

In this paper, we studied WVTR(water vapor transmission rate) properties of $Si_3N_4$ thin film that was deposited using TCP-CVD (transformer coupled plasma chemical vapor deposition) method for the possibility of OLED(organic light emitting diode) encapsulation. Considering the conventional OLED processing temperature limit of below $80^{\circ}C$, the $Si_3N_4$ thin films were deposited at room temperature. The $Si_3N_4$ thin films were prepared with the process conditions: $SiH_4$ and $N_2$, as reactive gases; working pressure below 15 mTorr; RF power for TCP below 500 W. Through MOCON test for WVTR, we analyzed water vapor permeation per day. We obtained that WVTR property below 6~0.05 gm/$m^2$/day at process conditions. The best preparation condition for $Si_3N_4$ thin film to get the best WVTR property of 0.05 gm/$m^2$/day were $SiH_4:N_2$ gas flow rate of 10:200 sccm, working pressure of 10 mTorr, working distance of 70 mm, TCP power of 500 W and film thickness of 200 nm. respectively. The proposed results indicates that the $Si_3N_4$ thin film could replace metal or glass as encapsulation for flexible OLED.

• Korean Journal of Materials Research
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• v.27 no.2
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• pp.89-93
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• 2017

A thin film thermoelectric generator that consisted of 5 p/n pairs was fabricated with $1{\mu}m$-thick n-type $In_3Sb_1Te_2$ and p-type $Ge_2Sb_2Te_5$ deposited via radio frequency magnetron sputtering. First, $1{\mu}m$-thick GST and IST thin films were deposited at $250^{\circ}C$ and room temperature, respectively, via radio-frequency sputtering; these films were annealed from 250 to $450^{\circ}C$ via rapid thermal annealing. The optimal power factor was found at an annealing temperature of $400^{\circ}C$ for 10 min. To demonstrate thermoelectric generation, we measured the output voltage and estimated the maximum power of the n-IST/p-GST generator by imposing a temperature difference between the hot and cold junctions. The maximum output voltage and the estimated maximum power of the $1{\mu}m$-thick n-IST/p-GST TE generators are approximately 17.1 mV and 5.1 nW at ${\Delta}T=12K$, respectively.