In this work, we report a decreasing number of isolated Mn in the aged EL phosphor layer, which was observed by EPR technique for the first time. Such phenomena can be explained by that during the operation of EL device, isolated Mn can easily diffuse into another site and then, the numbers of isolated Mn decrease due to forming cluster. Clustering seems to be a favorable process in this lattice due to the effect of energy lowering. Or, the electronic charge of the isolated Mn can be transfered into neighboring Mn ions via sulfur and/or sulfur vacancy. In these cases Mn^<2+> can be changed into Mn^<1+> or Mn^<3+>, Therefore, luminance may be lowered due to the decrease in the number of efficient emission center of Mn^<2+>.

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In order to study large area thin film electroluminescent (TFEL) devices, large area ZnS:Mn thin film has been grown by low pressure metalorganic chemical vapor deposition. The BCPM has been chosen as the Mn source and the optimum bubbler temperature is 75℃ The ACTFEL devices with double insulating layers structure have been made and the luminance is higher than 1500cd/m^2 which is higher than the previous reports.

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The principal cause that limits the life of dc PDP is sputtering of cathode in the discharge. Sputtered substances which deposited near the cathode were repeating cycles of deposition and disappearance. This cycle occurred simultaneously with changes in luminance and discharge voltage. Elemental analysis indicated that those substances are almost the same metals composing the cathode. The cycle must be due to the sputtered substances piling up and connecting with the cathode and then being sputtered again. The discharge characteristics of different cathode-area indicate that one reason for the reduction of discharge voltage is the increase of cathode area.

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MgO Paste of T-55 a was developed to apply thick-film-printing technology to fabricating MgO Protecting layer in ac PDPs. Annealing process of screen-printed MgO film was clarified by the DSC measurements. capability to apply sputtering method to fabricating MgO film was investigated. In the present work the reduction of the firing voltage is focused on applying a mixture of CaO and SrO to the protecting layer_ The basic characteristics of contamination on the protecting layer for several kinds of mixture of CaO and SrO were investigated by ESCA. n is clarified that firing voltage of the panel made by the only CaO is lower than that of MgO.

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The two-dimensional computer simulation program was completed and executed to clarify the operation mechanisms of the Barrier-Ribs Electrodes ac plasma Displays (BR-PDPs). The validity of the computer simulation program was testified, because the simulated results showed that the calculated results coincide completely with the measured results concerning the memory margin and saturation time of wall charge. From the simulated results it is proved that the wide memory margin of BR-PDPs with a very short pulse width is due to fast accumulation phenomena of the electron and the ion after the discharge is generated.

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To deal with the social trend where the phrase "user-friendly display" is prevailing, this year became a memorable year for the Japanese Industrial Standard (JIS), with the completion of the framework regarding the ergonomics-related standards, i.e. JIS Z 8500 through 8599. However, in drafting JIS Z 8513, which corresponds to Part 3 of ISO 9241, numerous problems were encountered. As a "genuine" standard, Part 3 of ISO 9241 should not be an international standard but a technical report as of 1992. Also, the draft of JIS Z 8513 itself contains some problems from the Asian cultural standpoint. Here, I present my opinion regarding these problems.

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One of the important performance parameters of a color monitor tube (CMT) is the sharpness impression. This is judged by the human eyes under certain application. The perceived sharpness or focus quality of a tube is also called the readability of the tube. It is related to the tube itself and the physiology of the human eyes, the perceptive processing of the brain, and the electronics of the set / testing table. This investigation is devoted to finding out a suitable / comfortable method or pattern for focus setting and classifying under the customer-like conditions.

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With an eye on high conductivity, antimony was introduced to pure SnO2 crystals. Through Coprecipitation and cross flow microfiltration of SnO2 and Sb2O5, doping of antimony in SnO2 by autoclaving, dialysis to remove undesired ions. sonifying of the final product, very tiny ATO particles were obtained. The anti-static coating solution containing ATO particles was applied by spin coating technique. After proper baking process, a uniform antistatic film with good electrical and mechanical properties can be achieved.

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The brightness-contrast is one of the major factors for the picture quality evaluation of TV displays. For the physical contrast evaluation of display, the luminance-contrast ratio has been measured with used the specified pattern such as window pattern. However an actual contrast perceived in human eyes is significantly affected by the brightness contrast phenomenon of vision. In this study, we obtained quantitative data on the effect of contrast phenomenon by the subjective evaluation experiment using the window pattern. It will be useful as basic data for the practical contrast evaluation for display devices.

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The 1st Korea-Japan Joint Vacuum Microelectronics Symposium was held in Seoul on July 9, 1993 in conjunction with the 5th Korean Vacuum Society Meeting. It was the predecessor of the 2nd Asian Vacuum Microelectronics Conference. It must be fortunate that the meeting has been extended to an Asia wide one. Ten invited speakers, five from each country presented talks at the Symposium. The Symposium was quite successful, and called intensive attention to the fields of vacuum microelectronics in Korea. The growing R & D activities, especially for the STM, AFM, FED, ELD, LCD and TFT technologies are noteworthy. A condiderable number of works have been reported at various academic meetings such as the Korean Vacuum Society Meeting, the Korean Semiconductor Conference, and group VME seminars. Recently, a new FEAD System developed and constructed by the J.D. Lee's Team of Seoul National University Semiconductor Research Center and Uni-Vacuum (Univac) was installed.

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Gated-Field-Emission Triode from the cone-tip formation process to its emission properties has been systematically characterized. Process simulation shows that the successful formation of the microtip structure is mainly determined by the migration length of the e-beam evaporated layer. The measured triode characteristics matches well with the simulated program in the saturation region with proper tip radius adjustment without an artificial field enhancement factor. The calculated enhancement factor matches well with other published data.

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This paper describe the use of Taguchi methods and a simulation tool to optimize the gated emitter for use In the Field Emission Display. Since analog data are needed for a full color FED, the device is optimized to achieve a linear dynamic response. The radius is considered as the uncontrollable factor and is assigned as noise factor. According a L18 orthogonal array, the emission condition is modeled and the factors affecting the emission are grouped in order to their importance. This provided the designer a new look into the device structure used for color FEDs.

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Gated field emitter arrays fabricated by Transfer Mold technique and field emission properties are described. Because of the sharpening effect on the tips by the Si single crystal mold surface oxidation, emitter tip radii are as Small as less than 10 nm. The Fowler-Nordheim Plots of the Mo gated emitter array became a straight line and l-V characteristics indicated rectification. Transfer Mold technique is suitable for fabricating sharp, uniform and reproducible gated emitter arrays, and for selecting appropriate emitter materials.

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Flat panel CRT to use field emitter arrays (FEAs) for electron source is called Field Emission Display (FED). The FED has several advantage as compared with LCDs, the FED has been taken an extreme interest for practical use. In the present paper, we fabricated the FEAs made of n-type silicon covered with the metal by photolithography. We measured the energy distribution of the field emitted electrons by an ac retarding field method, and considered their reults.

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N-type porous Si field emitter arrays (FEAs) have been fabricated by tip surface anodization to improve the emission characteristics. The gate voltage required for emission could be lowered by tip anodization and the emission current was enhanced by a factor of up to 10. FN (Fowler-Nordheim) plots for the FEAs before and after tip anodization revealed that the work function of the tips could be decreased and the emission from various FEAs With initially different characteristics could be homogeneously improved by tip surface anodization.

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The ZrO/W(100) surface has remarkably low work function and therefore, is used as a high bright cathode. In this study, the forming mechanism of the very low work function was investigated by means of X-ray photoelectron spectroscopy (XPS) and low energy electron diffraction (LEED). Formation of ZrO_2 on the W(100) surface was observed after depositing of a monolayer of Zr onto the surface followed by heating in O2. After a sequential flashing in a good vacuum condition, a XPS spectrum indicated an existence of ZrO composite, which is considered to be significant in lowering of the work function on the ZrO/W(100).

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Electron emission into vacuum from a thin plate of ferroelectric lead-zirconate-titanate (PZT) ceramic has been observed under the impression of electric field of pulse consisting of a pair of positive and negative voltages. The emitted charge increases with increasing the positive and the absolute negative voltages on the pulse and the collector voltage. The mimimum absolute value of the negative pulse for electron emission is 40V when the positive voltage is larger than 150V. The maxrmum peak current densi ' is 70Afcm2. It is considered from the electrode area and thickness dependences of the charge that electrons are emitted not only from the ceramic surface near the electrde edge but also through the thin metal electrode. The emitted charge per one pulse little depends on pulse frequency when it is less than 2kHz, and so the total current density can be enhanced by increasing the frequency. The emission is observed even at temperatures above Curie temperature. It is considered that the emission is induced by abrupt change of dielectric flux as well as the polarization reversal. Cathodoluminescence from phosophers excited by the emitted electroncs has been observed.

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The small internal volume of devices, such as FEDS and in general vacuum packaging of microelectronic devices, makes it more critical the choice of a suitable getter. Besides the geometrical constraints, the getter must meet other requisites: it is often needed that it is activated at temperatures not exceeding 400-500℃, exhibits high sorption performance at room temperature and good mechanical strength. Getters have been developed in different configurations including relatively thin porous layers deposited onto a metal substrate to meet these requirements. The sorption performance of such getter structures, for the main active gases and their physico-mechanical chardcteristics are reviewed and discussed, also giving some applicative hints.

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