We examined the photoluminescent behaviors of MgSiN2:Mn2+ and MgSiN2:Ce3+,Mn2+ phosphors for use in white-light-emitting diodes. The red emission from MgSiN2:Mn2+ phosphors consisted of two Gaussian components, P1 from a single Mn2+ ion and P2 from either Mn2+ pairs or clusters. Decay analysis based on the Yokota and Tanimoto equation identified long decay for P1 and fast decay for P2. Most importantly, Ce3+ codoping enhanced Mn2+ emission intensity; in particular, emission at 460 nm excitations was promoted by the Ce3+ codoping.

Spark plasma sintering ͑SPS͒ was employed to synthesize Sr 2 SiO 3.5 N 0.333 :Eu 2+ , Sr 2 SiO 3 N 0.667 :Eu 2+ , and Sr 2 SiO 2 N 1.333 :Eu 2+ for use in white light emitting diodes ͑LED͒ lightings. The SPS technique enabled a complete, rapid synthesis of these phosphors with ease, whereas it is difficult to produce nitridosilicate phosphors by any other conventional synthesis methods. The photoluminescent ͑PL͒ spectrum of Sr 2 SiO 3.5 N 0.333 :Eu 2+ had two emission peaks, one at 420 and the other at 526 nm. There existed a single peak at 529 nm in the case of Sr 2 SiO 3 N 0.667 :Eu 2+ . The PL spectrum of Sr 2 SiO 2 N 1.333 :Eu 2+ also had two peaks, one at 529 and the other at 600 nm. Even though the exact structure was not identified, it was revealed that the X-ray diffraction pattern of Sr 2 SiO 3.5 N 0.333 :Eu 2+ , Sr 2 SiO 3 N 0.667 :Eu 2+ , and Sr 2 SiO 2 N 1.333 :Eu 2+ was consistent with the PL data. The phosphor with the highest nitrogen content, Sr 2 SiO 2 N 1.333 :Eu 2+ , showed a broad emission band spanning almost the entire visible range, which may work best if coupled with either UV or blue LEDs.

Thin-film ͑Sr,Ba͒ 2 SiO 4 :Eu 2+ phosphors were pulsed-laser deposited on quartz glass, sapphire, and Si wafers. The processing conditions were optimized to reduce substrate temperature during deposition and also to avoid high-temperature postdeposition annealing and reduction. In this study, the maximum processing temperature was reduced to 700°C, which must be lowered even further to produce on-chip phosphor films. The exact composition of the film obtained under the optimum processing conditions was identified by Rietveld refinement analysis, and two-peak emission behavior was investigated based on the exact structure.Thin-film phosphors have drawn considerable attention in an attempt to apply them to various display applications. 1-12 In fact, many sulfide and oxide thin-film phosphors have been developed for use in inorganic electroluminescent devices. Thin-film phosphors have advantages over powders in terms of their superior adhesion properties, high image resolution, good heat resistance, reduced outgassing, and long-term stability. In this regard, various deposition techniques have been employed in the production of thin-film phosphors, including radio frequency ͑rf͒ sputtering, pulsed laser deposition ͑PLD͒, pulsed electron-beam evaporation, and even sol-gel spin coating or spray pyrolysis. 1-12 In particular, thin-film phosphors developed by PLD are of great interest. 1-4 In addition to display applications, thin-film phosphors have been investigated for use in light-emitting diodes ͑LEDs͒. The preferred LED phosphor, Y 3 Al 5 O 12 :Ce 3+ ͑YAG͒ and its variants, already has been successfully developed in a thin-film form using rf magnetron sputtering and PLD techniques. 13,14 The YAG:Ce thin-film phosphors deposited by these techniques require high-temperature processing, either during or after the deposition. For example, at least 1200°C annealing after film deposition is required to achieve a complete crystallization of the YAG:Ce thin films. When the combination of thin-film YAG:Ce phosphors with InGaN chips is the object, breakdown of the InGaN chip at such high temperatures must be avoided.͑Sr,Ba͒ 2 SiO 4 :Eu 2+ phosphors, the luminance and color chromaticity of which are comparable to those of the YAG:Ce phosphor at blue LED excitations, 14-19 have attracted considerable attention for use in white-light-emitting diodes ͑WLEDs͒. Another merit of these phosphors is the ability to tune the emission peak by varying the Sr/Ba ratio. Despite their practical development in the powder form, there has been no attempt to achieve thin-film type ͑Sr,Ba͒ 2 SiO 4 :Eu 2+ phosphors. Our ultimate goal is to develop thinfilm ͑Sr,Ba͒ 2 SiO 4 :Eu 2+ phosphors with a processing temperature that can be lowered in the production of on-chip phosphor films, thereby avoiding breakdown of the InGaN chip. In this study we were not able to secure a processing temperature low enough to avoid InGaN chip breakdown. However, by lowering the maximum processing temperature ͑substrate temperature͒ as low as 700°C and by skipping th...

: In recent years, the central ministries and regional self are competitively developing program for creating a trail and theme path by the increase of the number of trekkers. Even though these projects are developed in rural areas, it has been pointed out that most of projects do not directly linked to the revitalization of rural villages and improvement of non-farm income because of the main road itself as a resource in rural area. Therefore, in this study, we try to connect the citizen and the agriculture and rural area through the development of the green road which is the experience road with rural resource. To achieve this, we investigated the status and characteristics of the 36 villages where are the village was promoted various major project of first step.In second step, we considered the distinct characteristics of the area with conference of expert and site investigation for the final selection of 15 villages. Through two rounds' expert group consulting with checking, related literatures review and similar case-projects benchmarking, a riverside green road which is linked long distance trail and adjacent to the riverside was developed 15 courses by 2-development types proposed.

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