MgO Protective Layer Research Articles

13.5L: Late‐News Paper: Development of MgCaO Protective Layer of Plasma Display Panels for Decreased Discharge Voltage

AbstractPlasma display panels (PDPs) with an MgCaO protective layer and a new manufacturing process were achieved, with discharge voltage decreased while productivity was maintained. The evaporation rate of MgCaO became lower with the increasing Ca content, decreased by 20% at Ca 8 wt%. However, by changing several settings of evaporation, the evaporation rate of the Ca 8 wt% was improved to be comparable to that of MgO. The PDP with the Ca 8 wt% MgCaO protective layer decreased the discharge voltage by 12 V compared to that with the MgO protective layer. The life characteristics of the PDP with the MgCaO protective layer were the same as those with the MgO protective layer.

7.4: AC Plasma Displays with Gold Nanorods in the Protecting Layer

AbstractThis paper proposes a modified protective layer structure incorporating Au nanorods which lead to localized surface plasmon resonance at the infrared (IR) region. By inserting Au nanorods into the MgO protective layer, higher luminous efficacy and a reduction of the IR emission originating from the plasma discharge were obtained.

AC-PDP 특성 개선을 위한 MgCaO 보호층과 단결정 MgO 파우더 코팅에 대한 연구

In this study, we attempted to reduce firing voltage of AC-PDP by alloying MgO protective Layer with CaO. Also, spray coating of single crystal MgO powder has been used to improving Exo-electron emission characteristics and reducing the statistical discharge delay in plasma displays. The properties of discharge depending upon the single crystal MgO powder are investigated. Plasma display having powder coated MgCaO Protective Layer shows lower driving voltage and higher efficacy than of uncoated, conventional panel.

Toward Flexible Transparent Plasma Display: Optical Characteristics of Low-Temperature Fabricated Organic-Based Display Structure

We report a flexible transparent display based on a plasma display platform. The test panel was designed to 42-in VGA resolution since the proposed flexible transparent plasma display is targeted for use in large-area and lightweight displays in order to replace windows. A test panel was fabricated with organic materials, with the exception of an electrode and the MgO protective layer. A polyethylene terephthalate (PET) plastic film was used as the substrate. The maximum temperature applied to PET substrates during the test panel fabrication was 60 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">°</sup> C. Each inner component had a high transparency of over 90%. The average transmittance of the test panel was 57.5% in the visible spectral range.

Discharge Characteristics of Plasma Display Panels with SrCaO Protective Layer Manufactured Using &amp;ldquo;All-in-Vacuum&amp;rdquo; Process

Plasma display panels (PDPs) with a SrCaO protective layer of high secondary electron emission coefficient were manufactured using the “all-in-vacuum” process, whereby the protective layer deposition and panel sealing were performed continuously in high vacuum in order to keep the surface of the protective layer as clean as possible. The PDP with the SrCaO protective layer manufactured using the “all-in-vacuum” process (“all-in-vacuum” SrCaO-PDP) for Ne­20 vol% Xe exhibited a luminance 2.1 times larger, a luminous efficacy 1.7 times larger, and the same discharge time lag, compared with the PDP with the MgO protective layer manufactured using the conventional process (conventional MgO-PDP) for Ne­4 vol% Xe, which had almost the same discharge voltage. [doi:10.2320/matertrans.M2011181]

Improvement in Discharge Delay Time by Accumulating Positive Wall Charges on Cathode MgO Protective Layer Surface in Alternating-Current Plasma Display Panels

The improvement in discharge delay time by accumulating positive wall charges on a cathode MgO protective layer surface in plasma display panels (PDPs) was investigated. The number of exoelectrons emitted from the cathode MgO surface, which trigger the discharge, increases with the accumulation of positive wall charges on the cathode MgO surface, thereby reducing both the statistical and formative delay times, ts and tf, respectively, of the address discharge. The correlations between exoelectron emission and ts and tf were investigated, revealing that the address discharge is triggered by multiple exoelectrons. In addition, it is found that exoelectron emission plays an important role in wall charge leakage during the address period. The present results confirmed that the accumulation of positive wall charges on the cathode MgO protective layer surface is effective for improving the discharge delay times ts and tf in not only PDPs but also common dielectric barrier discharge.

Improvement in Discharge Delay Time by Accumulating Positive Wall Charges on Cathode MgO Protective Layer Surface in Alternating-Current Plasma Display Panels

Improvement in Discharge Delay Time by Accumulating Positive Wall Charges on Cathode MgO Protective Layer Surface in Alternating-Current Plasma Display Panels

Influence of Gold Nanoparticles on the Characteristics of Plasma Display Panels

This paper proposes a modified alternating current plasma display panel (PDP) in which gold nanoparticles are incorporated into a bare MgO layer to enhance the performance of the protective layer. The proposed structure's ion-induced secondary electron yield, which is expressed in a gamma value ( value) is greater than that of a bare MgO layer; as a result, the operating voltage decreases by 10 V to 20 V. The integration of emitted infrared (IR) light and the power density consumed by the discharge current are both increased, but the ratio of increment is greater for the case of the IR light. Consequently, IR efficacy is increased. The IR response time of the sustain discharge and the address discharge time lag are reduced by the enhanced wall charge accumulation characteristic and the exoelectron emission property. The results of ultraviolet photoelectron spectroscopy show that a MgO layer with Au nanoparticles has a lower work function than a conventional bare MgO layer. Furthermore, the structure that is not flattened by nanoparticles seems to enhance the secondary electron emission property of the MgO protective layer. Consequently, the value is enhanced by the two reasons previously mentioned.

Accumulation and Decay Characteristics of Exoelectron Sources at MgO Protective Layer Surface in Alternating-Current Plasma Display Panels

The accumulation and decay characteristics of exoelectron sources at a MgO protective layer surface in alternating-current plasma display panels (AC-PDPs) were investigated. The positively charged MgO surface provides a larger number of exoelectrons than the negatively charged surface, indicating that electrons trapped in shallow carrier traps coexist with trapped holes, and exoelectrons are emitted through Auger and/or photoionization processes after their recombination. The exoelectron sources are accumulated by sustain discharges and always decay. The half-life of the decay of the exoelectron sources is relatively long, of the order of a few tens of ms, confirming that the exoelectron emission property at the address discharge in a certain television (TV) field is strongly affected by sustain firings in the previous two TV fields or more. The effects of such a long-term decay of the exoelectron sources should be taken into consideration when designing the driving waveforms of AC-PDPs.

P‐91: AC Plasma Display Panel with Gold Nano‐particles Inserted into an MgO Protective Layer

AbstractA modified MgO structure incorporating gold nano‐particles is proposed in this work. By inserting gold nano‐particles into the MgO protective layer, dozens of nanometer‐scale bumps are created on its surface. The change in the morphology due to these bumps induces a higher secondary electron emission rate, which both increases the luminous efficacy and causes a 20 V reduction of the driving voltage.

35.2: Invited Paper: A Consideration of Excitation and De‐excitation Process of MgO Protective Layer

AbstractDynamic response of MgO protective layer to VUV irradiation and discharge is investigated by using cathode luminescence (CL) spectroscopy, thermolimunescence (TL) spectroscopy and exo‐ electron analysis. The dynamics of excitation and de‐excitation processes of electron and hole traps are discussed.

49.3: Discharge Characteristics of PDPs with the Ternary Oxides Protective Layers Manufactured by Using All‐In‐Vacuum Process

AbstractThe discharge characteristics of PDPs with the protective layers of MgO based ternary oxides are investigated. The panels with a gas mixture of Ne‐Xe20% are manufactured by “all‐in‐vacuum” process, in which the front panels are processed without an exposure to ambient air after the deposition of protective layer. Compared with PDPs with conventional MgO protective layer, a discharge voltage is lowered by 40V and a discharge time lag is shortened within 1 μs.

Fe가 첨가된 MgO 보호막의 표면특성 개선에 관한 연구

플라즈마 디스플레이 패널(Plasma Display Panel : PDP)이 다른 평판 디스플레이 분야(Liquid Crystal Displays(LCDs) and organic light emitting diodes(OLEDs) 등)와 경쟁에서 이기기 위해서는 제품의 고화질화, 저소비전력와 고속구동 등의 성능향상이 필요하다. 본 논문에서는 PDP의 성능향상을 위하여 유전체 보호층으로 쓰이는 MgO 박막에 Fe를 미량 첨가한 박막을 증착하고, 그 특성에 대하여 연구하였다. e-beam 증착법으로 증착된 Fe 도핑 된 MgO 박막의 표면특성과 전기광학적 특성을 4인치 테스트 패널을 제작하여 연구하였다. Fe가 도핑된 MgO 박막을 가지는 PDP는 Fe가 도핑되지 않은 PDP에 비해 낮은 방전전압 특성을 나타내었으며, 이는 박막에서 측정된 2차전자방출계수의 실험결과와 잘 일치되었다. 증착된 박막의 결정성과 표면 거칠기는 XRD 와 AFM 측정방법을 통하여 결정되었다. 또한, Fe가 도핑된 PDP는 고속구동을 위한 향상된 어드레스 방전 늦음의 특성을 나타내었다.

Correlation between the Secondary Electron Emission Coefficient of MgO Protective Layer and Luminous Efficiency in Alternating Current Plasma Display Panel (AC-PDP)

We have investigated the correlation between the secondary electron emission coefficient (γ) of MgO protective layer and discharge luminous efficiency in alternating current plasma display panel (AC-PDP) by varying the O2 flowing rates of 0, 10, 20, and 30 sccm. It is found that the secondary electron emission coefficient and the brightness are maximum, and the discharge voltage is minimum at the O2 flowing rate of 20 sccm. As a result, the discharge luminous efficiency is the highest at the O2 flowing rate of 20 sccm in comparison with others.

P‐96: Discharge Characteristics of AC PDP with Fe Doped MgO Protective Layer

AbstractWe introduced an Fe doped MgO thin films as a protective layer in an AC PDP, in order to improve the discharge characteristics of MgO thin film. We investigated both the surface characteristics of the deposited thin films and the electro‐optical properties of four inch test panels. We determined the crystallinity and surface roughness of thin films by examining XRD patterns and AFM images. We demonstrated experimentally that an AC PDP with an Fe doped MgO protective layer has a lower discharge voltage and improved addressing jitter than that of undoped MgO film corresponding to measured secondary electron emission coefficients.

26.3: Effect of Seed Particles on Exaggerated Grain Growth of Redeposited MgO Layer during Accelerated Discharge Testing of AC‐PDPs

AbstractReconstruction and exaggerated grain growth (EGG) behaviors of redeposited MgO layer were observed and analyzed theoretically with the addition of dopant and MgO seed particle. The reconstruction and EGG are closely correlated with the driving force for nucleation and growth, interface energy and initial size distribution of MgO protective layer and this is believed to be caused by the formation of charged clusters in the plasma spaces during discharge in AC‐PDPs.

Measurement of the properties of a flat-panel gas X-ray detector

Recently, large-area image detectors were investigated for X-ray imaging in medical diagnostic and other applications. In this paper, a new flat-panel gas detector for diagnostic X-ray imaging is proposed, and its characteristics are investigated. Research on flat-panel gas detectors is scarce, because of the difficulties of injecting gas against atmospheric pressure. So almost all gas detectors are designed as a chamber. We made a flat-panel sample by display technique (e.g. plasma display panel, field emission display, etc.). Transparent electrodes, dielectric layer, and MgO protection layer were formed in the front glass. Additionally, X-ray phosphor layer and address electrodes were formed in the rear glass. Dark current, X-ray sensitivity, and linearity as a function of electric field were measured to investigate the electrical properties. From the results, the stabilized dark current density and significant X-ray sensitivity were obtained. A good linearity as a function of exposure dose could be realized in a wide diagnostic energy range. These results mean that the passive matrix-addressed flat-panel gas detector can be used for digital X-ray imaging.

Discharge characteristics of plasma display panels with Si-doped MgO protective layers

We report on our study of the influence of varying concentrations of Si doping on the secondary electron emission (SEE) yield of MgO thin films prepared by electron beam evaporation technique. The series of Si-doped MgO films were microstructurally characterized with various tools like X-ray diffraction, scanning electron microscopy and atomic force microscopy. The optimization of the concentration of Si doping is seen to enhance the SEE yield. We discuss the correlation of SEE yield in the context of different deposition and measurement conditions and crystalline orientation.

A study on the driving discharge characteristics of the AC PDP packaged with in-situ vacuum sealing with the MgO layer coated by optimum evaporation rate

AC PDP with MgO protective layer coated with the optimum evaporation rate of 5 Å/s can generate more enhanced efficiency through the vacuum in-line sealing process. However, the optimized process conditions still require the optimum driving scheme on the ramp-up and ramp-down slope of the reset waveform for enhancing discharging efficiency. For the in-situ vacuum sealed PDP with the optimum evaporation rate of MgO protective layer, the delay times of address discharge were investigated with various slopes of ramp waveforms during a reset ramp-up and ramp-down period. And the optimal driving scheme was also obtained.

The effect of Fe-doped magnesium oxide thin film in alternative current plasma display panel

In order to improve the discharge characteristics of MgO thin film as a protective layer in an alternative current plasma display panel, Fe-doped MgO thin films was introduced. Both the surface characteristics of the deposited thin films and the electro-optical properties of 4 inch test panels were investigated. It has been demonstrated experimentally that ac PDP with Fe-doped MgO protective layer has lower discharge voltage than that of undoped MgO film, which corresponds to measured secondary electron emission coefficients. The crystallinity and surface roughness of thin films were determined by XRD patterns and AFM images.