• Journal of Electrical Engineering and Technology
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• v.2 no.4
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• pp.525-531
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• 2007

Ni(75 wt.%)-Cr(20 wt.%)-Al(3 wt.%)-Mn(4 wt.%)-Si(1 wt.%) alloy thin films were prepared using the DC magnetron sputtering process by varying the sputtering conditions such as power, pressure, substrate temperature, and post-deposition annealing temperature in order to fabricate a precision thin film resistor. For all the thin film resistors, sheet resistance, temperature coefficient of resistance (TCR), and crystallinity were analyzed and the effects of sputtering conditions on their properties were also investigated. The oxygen content and TCR of Ni-Cr-Al-Mn-Si resistors were decreased by increasing the sputtering pressure. Their sheet resistance, TCR, and crystallinity were enhanced by elevating the substrate temperature. In addition, the annealing of the resistor thin films in air at a temperature higher than $300^{\circ}C$ lead to a remarkable rise in their sheet resistance and TCR. This may be attributed to the improved formation of NiO layer on the surface of the resistor thin film at an elevated temperature.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.18 no.2
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• pp.72-75
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• 2008

Zinc oxide (ZnO) thin films were prepared by a sol-gel method. The structural and electrical properties were investigated by varying drying and annealing temperatures. The thin films were coated (250 nm) by spin-coating method on glass substrates. The optimum drying temperature of ZnO thin films was 300$^{\circ}C$ where the resistivity was the lowest and the preferred c-axis orientation was the highest. The annealing was carried out in air and inert atmospheric conditions. The degree of the preferred c-axis orientation was estimated. The highest preferred c-axis orientation was recorded at 600$^{\circ}C$. The preferred c-axis orientation and grain growth resulted in the mobility enhancement of the ZnO thin films, and the lowest resistivity was 0.62${\Omega}{\cdot}cm$ at 600$^{\circ}C$.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1469-1472
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• 2006

We investigated the electrical and optical properties of ZnO:Al thin films as a function of the thermal process conditions. The film was prepared by RF magnetron sputtering followed by annealing in a box furnace in air. An ZnO:Al (98:2) alloy with the purity of 99.99% (3 inch diameter) was used as the target material. The electrical properties of the transparent electrode, exhibited surface oxidation as a result of rapid oxygen absorption with increasing annealing temperature. The processed ZnO:Al films and commercial ITO(indium-tin-oxide) were applied to an OLED stack to investigate the current density and luminescence efficiency. The efficiency of the device using the ZnO:Al electrode was higher than that from the device using the ITO electrode.

• Journal of the Korean Ceramic Society
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• v.40 no.7
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• pp.652-656
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• 2003

The green emitting phosphor, BnGa$_2$O$_4$:Mn thin films with spinel structure were deposited by rf magnetron sputtering at various Ar/O$_2$ ratios. Thin film phosphors were heat-treated in air and $N_2$+vacuum atmosphere, respectively. Effects of Ar/O$_2$ ratios and annealing conditions on the structural and photoluminescence (PL) and cathodeluminescence (CL) properties were investigated. Luminous properties were more improved by inhibiting the films from contacting with oxygen during heat treatment.

• Journal of the Korean institute of surface engineering
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• v.29 no.6
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• pp.621-627
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• 1996

$SrBi_{2x}TaO_9$ ferroelectric thin films were prepared on platinized silicon substrates using MOD proces, and crystallization behavior of the films was investigated with variation of the annealing temperature and Bi content x. Crystalline phase of bismuth layered perovskite structure was formed even by baking the films at $800^{\circ}C$ for 5 minutes in air, and was not changed by annealing at temperatures raning from $700^{\circ}C$ to $900^{\circ}C$ for 1 hour in oxygen ambient. When $SrBi_{2x}TaO_9$ thin films ($0.8\lex\ie1.6$) were annealed at $800^{\circ}C$, Preferred orientation of the films along c-axis was observed with $x\ge1.2$. With increasing Bi content x, surface morphology of the films was changed from equiaxed grains to elongated grains.

• Applied Science and Convergence Technology
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• v.24 no.6
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• pp.268-272
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• 2015

We report the systematic study to reduce extrinsic doping in graphene grown by chemical vapor deposition (CVD). To investigate the effect of crystallinity of graphene on the extent of the extrinsic doping, graphene samples with different levels of crystal quality: poly-crystalline and single-crystalline graphene (PCG and SCG), are employed. The graphene suspended in air is almost undoped regardless of its crystallinity, whereas graphene placed on an $SiO_2/Si$ substrate is spontaneously p-doped. The extent of p-doping from the $SiO_2$ substrate in SCG is slightly lower than that in PCG, implying that the defects in graphene play roles in charge transfer. However, after annealing treatment, both PCG and SCG are heavily p-doped due to increased interaction with the underlying substrate. Extrinsic doping dramatically decreases after annealing treatment when PCG and SCG are placed on the top of hexagonal boron nitride (h-BN) substrate, confirming that h-BN is the ideal substrate for reducing extrinsic doping in CVD graphene.

• Transactions on Electrical and Electronic Materials
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• v.11 no.4
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• pp.182-185
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• 2010

$Pb_{0.99}[(Zr_{0.6}Sn_{0.4})_{0.9}Ti_{0.1}]_{0.98}Nb_{0.02}O_3$ (PNZST) thin films were deposited by radio frequency magnetron sputtering on a $(La_{0.5}Sr_{0.5})CoO_3$ (LSCO)/Pt/Ti/$SiO_2$/Si substrate using a PNZST target with an excess PbO of 10 mole%. The thin films deposited at the substrate temperature of $500^{\circ}C$ crystallized to a perovskite phase after rapid thermal annealing (RTA). The thin films, which annealed at $650^{\circ}C$ for 10 seconds in air, exhibited good crystal structures and ferroelectric properties. The remanent polarization and coercive field of the fabricated PNZST capacitor were approximately $20uC/cm^2$ and 50 kV/cm, respectively. The reduction of the polarization after $2.2\;{\times}\;10^9$ switching cycles was less than 10%.

• Korean Journal of Materials Research
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• v.16 no.7
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• pp.401-407
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• 2006

ZnO is well-known as a promising material for optical communication systems and electronic displays. ZnO:Er thin films were deposited on c-plane sapphire substrates by rf magnetron sputtering, and the effects of sputtering parameters and the annealing conditions on the luminescence in the visible range were investigated. Luminescent properties depended on the crystallinity of films and annealing atmosphere. Highly c-axis oriented ZnO:Er films showed a strong emission band at 465 nm and a weak emission at 525 nm due to the energy transition of $^{4}I_{15/2}-^{4}F_{5/2}\;and\;^{4}I_{15/2}-^{2}H_{11/2}$, respectively. ZnO:Er thin films annealed at air atmosphere were superior to those annealed in $H_2$ in photoluminescence intensity.

• Journal of Industrial Technology
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• v.32 no.A
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• pp.119-123
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• 2012

Diamond-like carbon(DLC) thin films with interlayer were deposited on silicon substrate using a reactive sputtering method. The thermal stability of the films was investigated by annealing the films for 1hr in air in the range of 100 to $500^{\circ}C$. The $I_D/I_G$ ratio increased with increasing temperature as related to the $sp^3-to-sp^2$transition. Accordingly, G-position shifting started from $150^{\circ}C$ in the DLC films and from $270^{\circ}C$ in the a-Si/DLC films. Moreover, in the case of the a-Si/DLC films the film still observed even after annealing at $500^{\circ}C$. The thermal stability of the reactive sputtered DLC films appeared to be improved by the a-Si interlayer.

• Journal of the Korean Magnetics Society
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• v.5 no.5
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• pp.720-725
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• 1995

Bi-substituted gadolinium iron garnet films were deposited on GGG(111) and NGG (111) substrates by irradiating KrF excimer laser onto targets having compositions of $Bi_{x}Gd_{3-x}Fe_{5}O_{12}$ ($2.0{\leq}x{\leq}3.0$) under substrate temperature of $580~620^{\circ}C$. Analysis on structure, composition and angle of Faraday rotation, ${\theta}_{F}$, were carried out. The composition, the structure and the magneto-optical properties of the obtained films were found to be strongly dependent both on the compositions of the targets and on the pressure of oxygen. Before annealing in air, all films showed ${\theta}_{F}{\geq}0$ at ${\lambda}=6328{\AA}$, while several films showed ${\theta}_{F}{\leq}0$ after the annealing. The highest value of Bi-substitution up to x = 1.76 with uniform composition was obtained.