• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.485-486
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• 2005

Fringe-field switching mode which has a horizontal and vertical electric field exhibits high transmittance and wide viewing angle characteristics. In the FFS mode, a passivation layer between common and pixel electrodes exists, which functions as preventing current leakage of fringe-field. In this paper, we have studied LC behavior, transmittance and operating voltage characteristics with applied voltage as a function of the passivation layer thickness and defined optimal value of the layer to be about $0.5{\mu}m$.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.1
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• pp.60-64
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• 2003

In this study, the inorganic thin-film passivation layer was newly adopted to protect the organic layer from moisture and oxygen. Using the electron beam evaporation system, the various kinds of inorganic thin-films were deposited onto the organic layer and their interface properties between organic and inorganic layer were investigated. In this investigation, the MgO layer showed the most suitable properties, and based on this result, the time dependent emission properties were estimated for the OLED with and without passivation layer. In this experiment, we can see that the time-dependent emission properties of MgO passivated OLED had longer life-time compared to non-passivated OLED. Therefore, we can consider that the MgO thin film is one of the most suitable candidates for the thin-film passivation layer of OLED.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.6
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• pp.538-546
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• 2006

We report on characteristics of specially designed inductively-coupled-plasma chemical vapor deposition (ICP-CVD) system for top-emitting organic light emitting diodes (TOLEDs). Using high-density plasma on the order of $10^{11}$ electrons/$cm^3$ generated by linear-type antennas connected in parallel and specially designed substrate cooling system, a 100 nm-thick transparent $SiN_{x}$ passivation layer was deposited on thin Mg-Ag cathode layer at substrate temperature below $50\;^{\circ}C$ without a noticeable plasma damage. In addition, substrate-mask chucking system equipped with a mechanical mask aligner enabled us to pattern the $SiN_x$ passivation layer without conventional lithography processes. Even at low substrate temperature, a $SiN_x$ passivation layer prepared by ICP-CVD shows a good moisture resistance and transparency of $5{\times}10^{-3}g/m^2/day$ and 92 %, respectively. This indicates that the ICP-CVD system is a promising methode to substitute conventional plasma enhanced CVD (PECVD) in thin film passivation process.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2006.06a
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• pp.71-72
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• 2006

We report on plasma damage free chemical vapor deposition technique for the thin film passivation of organic light emitting diodes (OLEDs), organic thin film transistor (OTFT) and flexible displays using catalyzer enhanced chemical vapor deposition (CECVD). Specially designed CECVD system has a ladder-shaped tungsten catalyzer and movable electrostatic chuck for low temperature deposition process. The top emitting OLED with thin film $SiN_x$ passivation layer shows electrical and optical characteristics comparable to those of the OLED with glass encapsulation. This indicates that the CECVD technique is a promising candidate to grow high-quality thin film passivation layer on OLED, OTFT, and flexible displays.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.06a
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• pp.114-115
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• 2007

In this paper, it was demonstrated that organic thin-film transistors (OTFTs) were fabricated with the organic passivation layer by vapor deposition polymerization (VDP) processing, In order to form polymeric film as an passivation layer, VDP process was also introduced instead of spin-coating process, where polymeric film was co-deposited by high-vacuum thermal evaporation from 6FDA and ODA followed by curing, Field effect mobility, threshold voltage, and on-off current ratio with 450-nm-thick organic passivation layer were about $0.21\;cm^2/Vs$, IV, and $1\;{\times}\;10^5$, respectively.

• The Korean Journal of Ceramics
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• v.3 no.2
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• pp.92-95
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• 1997

Because of the novel characteristics such as chemical stability, hardness, electrical resistivity and thermal conductivity, diamond-like carbon (DLC) film is a suitable material for the passivation layers. For this purpose, using the PECVD, DLC films were synthesized at room temperature. The adhesion and the hardness of the DLC films deposited on Si an SiO2 substrate were measured. The resistivity of 5.3$\times$$10^8$$\Omega$.cm was measured by automatic spreading resistance probe analysis method. The thermal conductivities of different DLC films were measured and compared with that of phospho silicate glass (PSG) film which is commonly used as passivation layers. The thermal conductivity of DLC film was improved by increasing hydrogen flow rate up to 90 sccm and was better than that of PSG film. The patterning techniques of the DLC film developed using the RIE and the lift-off method to form 5$\mu\textrm{m}$ line. Finally, the thermal characteristics of the power transistor with the DLC film as passiviation layer was analyzed.

• 한국정보디스플레이학회:학술대회논문집
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• 2007.08b
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• pp.1539-1542
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• 2007

We have synthesized novel organic passivation materials to protect organic thin film transistors (OTFTs) from $H_2O$ and $O_2$ using polyvinyl alcohol (PVA)/layered silicate (SWN) nano composite system. Up to 3 wt% of layered silicate to PVA, very homogeneous nanocomposite solution was prepared.

• Transactions on Electrical and Electronic Materials
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• v.13 no.2
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• pp.93-97
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• 2012

In this study, the fabrication and the characteristic analyses of OLED using in-situ passivation are investigated. OLEDs represent a disadvantage in decreasing its life due to the degradation caused by the penetration of moisture and oxygen. After the fabrication of OLED, an in-situ passivation method for inorganic thin films is developed. A process that uses PECVD method which can apply a vapor deposition process at room temperature is also developed. Changes in the degradation and electric characteristics of OLEDs are also analyzed by applying $SiO_2$ and SiNx thin films to OLED as a passivation layer. By applying the fabricated thin film to OLEDs as a passivation layer, the moisture penetration in a single layer film is ensured below $1{\times}10^{-2}\;g/m^2.day$. This leads to the improvement of such degradation characteristics in the application of multilayer films.

• Proceedings of the Materials Research Society of Korea Conference
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• 2002.11a
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• pp.189-189
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• 2002

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.26 no.10
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• pp.754-759
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• 2013

Aluminum oxide($Al_2O_3$) film deposited by atomic layer deposition (ALD) is known to supply excellent surface passivation properties on crystalline Si surfaces. Since $Al_2O_3$ has fixed negative charge, it forms effective surface passivation by field effect passivation on the rear side in p-type silicon solar cell. However, $Al_2O_3$ layer formed by ALD process needs very long process time, which is not applicable in mass production of silicon solar cells. In this paper, plasma-assisted ALD(PA-ALD) was applied to form $Al_2O_3$ to reduce the process time. $Al_2O_3$ synthesized by ALD on c-Si (100) wafers contains a very thin interfacial $SiO_2$ layer, which was confirmed by FTIR and TEM. To improve passivation quality of $Al_2O_3$ layer, the deposition temperature was changed in range of $150{\sim}350^{\circ}C$, then the annealing temperature and time were varied. As a result, the silicon wafer with aluminum oxide film formed in $250^{\circ}C$, $400^{\circ}C$ and 10 min for the deposition temperature, the annealing temperature and time, respectively, showed the best lifetime of 1.6ms. We also observed blistering with nanometer size during firing of $Al_2O_3$ deposited on p-type silicon.