• Journal of Electrical Engineering and Technology
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• v.6 no.5
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• pp.688-692
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• 2011

Carbon nanotubes (CNTs) are vertically grown inside high-aspect-ratio vertical pores of anodized aluminum oxide. A CNT catalyst layer is introduced by atomic layer deposition to the bottom of the pores, after which the CNTs are successfully grown from the layer using chemical vapor deposition. The CNTs formed a complete vertical conductive path. The conductivity of the CNT-vertical path is also measured and discussed. The present atomic layer deposition-incorporated catalyst deposition is predicted to enable the integration of CNTs with various challenging configurations, including high-aspect-ratio vertical channels or vertical interconnects.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.274-274
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• 2013

We fabricate encapsulation-layer of OLED panel from organic-inorganic hybrid thin film by atomic layer deposition (ALD) molecular layer deposition (MLD) using Al2O3 as ALD process and Adipoyl Chloride (AC) and 1,4-Butanediamine as MLD process. Ellipsometry was employed to verify self-limiting reaction of MLD. Linear relationship between number of cycle and thickness was obtained. By such investigation, we found that desirable organic thin film fabrication is possible by MLD surface reaction in monolayer scale. Purging was carried out after dosing of each precursor to eliminate physically adsorbed precursor with surface. We also confirmed roughness of the organic thin film by atomic force microscopy (AFM). We deposit AC and 1,4-Butanediamine at $70^{\circ}C$ and investigated surface roughness as a function of increasing thickness of organic thin film. We confirmed precursor's functional group by IR spectrum. We calculated WVTR of organic-inorganic hybrid super-lattice epitaxial layer using Ca test. WVTR indicates super-lattice film can be possibly use as encapsulation in flexible devices.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.373-373
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• 2012

We fabricated conductive zinc oxide (ZnO) thin film at low temperature by UV-enhanced atomic layer deposition. The atomic layer deposition relies on alternate pulsing of the precursor gases onto the substrate surface and subsequent chemisorption of the precursors. In this experiment, diethylzinc (DEZ) and $H_2O$ were used as precursors with UV light. The UV light was very effective to improve the conductivity of the ZnO thin film. The thickness, transparency and resistivity were investigated by ellisometry, UV-visible spectroscopy and Four-point probe.

• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.84.2-84.2
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• 2011

In this research, two thin film deposition techniques, Atomic Layer Deposition and Sputtering are carried out for the fabrication of Yittria Stabilized Zirconia electrolyte for thin film Solid Oxide Fuel Cell. Zirconium to Yittrium ratio for both cases is about 1/8. Scanning Electron Microscope(SEM) image shows that the growth rate per hour for Atomic Layer Deposition is faster than for sputtering. X-ray Photo-electron Spectroscopy(XPS) shows that the peaks of both Zirconia and Yittria shift towards higher bending energy for the case of Atomic Layer deposition and thus are more strongly attached to the substrate. Later, Nyquist plot was used to compare the conductivity of Yittria Stabilized Electrolyte for both cases. The conductivity at $300^{\circ}C$ for Atomic Layer Deposited Yittria Stabilized Zirconia is found to be $5{\times}10^{-4}S/cm$ while that for sputtered Yittria Stabilized Zirconia is $2{\times}10^{-5}S/cm$ at the same temperature. The reason for better performance for Atomic Layered YSZ is believed to be the Nano-structured layer fabrication that aids in along the plane conduction as compared to the columnarly structured Sputtered YSZ.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.280.2-280.2
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• 2016

The graphene, a single atomic sheet of graphite, has attracted tremendous interest owing to its novel properties including high intrinsic mobility, optical transparency and flexibility. However, for more diverse application of graphene devices, it is essential to tune its transport behavior by shifting Dirac Point (DP) of graphene. So, in the following context, we suggest a method to tune structural and electronic properties of graphene using atomic layer deposition. By atomic layer deposition of zinc oxide (ZnO) on graphene using 4-mercaptophenol as linker, we can fabricate n-doped graphene. Through ${\pi}-{\pi}$ stacking between chemically inert graphene and 4-mercaptophenol, conformal deposition of ZnO on graphene was enabled. The electron mobility of graphene TFT increased more than 3 times without considerably decreasing the hole mobility, compared to the pristine graphene. Also, it has high air stability. This ZnO doping method by atomic layer deposition can be applicable to large scale array of CVD graphene TFT.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.27 no.10
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• pp.642-647
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• 2014

For feasible study of opto-electrical application regarding to oxide semiconductor, we implemented the N doped ZnO growth using a atomic layer deposition technique. The p-type ZnO deposition, necessary for ZnO-based optoelectronics, has considered to be very difficulty due to sufficiently deep acceptor location and self-compensating process on doping. Various sources of N such as $N_2$, $NH_3$, NO, and $NO_2$ and deposition techniques have been used to fabricate p-type ZnO. Hall measurement showed that p-type ZnO was prepared in condition with low deposition temperature and dopant concentration. From the evaluation of photoluminescence spectroscopy, we could observe defect formation formed by N dopant. In this paper, we exhibited the electrical and optical properties of N-doped ZnO thin films grown by atomic layer deposition with $NH_3OH$ doping source.

• Journal of the Semiconductor & Display Technology
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• v.20 no.3
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• pp.22-26
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• 2021

Thin-film encapsulation (TFE) technology is most effective in preventing water vapor and oxygen permeation in the organic light emitting diodes (OLED). Of those, a laminated structure of Al₂O₃ and MgO were applied to provide efficient barrier performance for increasing the stability of devices in air. Atomic layer deposition (ALD) method is known as the most promising technology for making the laminated Al₂O₃/MgO and is used to realize a thin film encapsulation technology in organic light-emitting diodes. Atomic layer deposited inorganic films have superior barrier performance and have advantages of excellent uniformity over large scales at relatively low deposition temperatures. In this study, the control system of the MgCP₂ precursor for the atomic layer deposition of MgO was established in order to deposit the MgO layer stably by the injection time of second level and the stable heating temperature. The deposition rate was obtained stably to be from 4 to 10 Å/cycle using the injection pulse times ranging from 3 to 12 sec and a substrate temperature ranging from 80 to 150 ℃.

• Korean Journal of Chemical Engineering
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• v.35 no.12
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• pp.2474-2479
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• 2018

Plasma-enhanced atomic layer deposition (PEALD) is well-known for fabricating conformal and uniform films with a well-controlled thickness at the atomic level over any type of supporting substrate. We prepared nickel oxide (NiO) thin films via PEALD using bis(ethylcyclopentadienyl)-nickel ($Ni(EtCp)_2$) and $O_2$ plasma. To optimize the PEALD process, the effects of parameters such as the precursor pulsing time, purging time, $O_2$ plasma exposure time, and power were examined. The optimal PEALD process has a wide deposition-temperature range of $100-325^{\circ}C$ and a growth rate of $0.037{\pm}0.002nm$ per cycle. The NiO films deposited on a silicon substrate with a high aspect ratio exhibited excellent conformality and high linearity with respect to the number of PEALD cycles, without nucleation delay.

• Proceedings of the Materials Research Society of Korea Conference
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• 2007.11a
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• pp.32.1-32.1
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• 2007

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.312.1-312.1
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• 2016

We have deposited ZnO thin films by ultraviolet (UV) enhanced atomic layer deposition using diethylznic (DEZ) and water (H2O) as precursors with UV light. The atomic layer deposition relies on alternating dose of the precursor on the surface and subsequent chemisorption of the precursors with self-limiting growth mechanism. Though ALD is useful to deposition conformal and precise thin film, the surface reactions of the atomic layer deposition are not completed at low temperature in many cases. In this experiment, we focused on the effects of UV radiation during the ALD process on the properties of the inorganic thin films. The surface reactions were found to be complementary enough to yield uniform inorganic thin films and fully react between DEZ and H2O at the low temperature by using UV irradiation. The UV light was effective to obtain conductive ZnO film. And the stability of TFT with UV-enhanced ZnO was improved than ZnO by thermal ALD method. High conductive UV-enhanced ZnO film have the potential to applicability of the transparent electrode.