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経営理念浸透施策に対する従業員知覚の理念共有への影響を、定性・定量データ両方から検討した。特にＡ社33名の定性的調査から抽出された施策の「熱心さ」「日常業務への配慮」知覚、及び施策の「押付感」知覚について、2,906名のデータで定量的に検証を行った。その結果、前者は従業員の理念共有を促進し、後者は停滞させることが分析された。これらの分析を踏まえ、経営理念浸透施策を企画・実施する際の視点や思考の在り方について議論がなされる。

Wide bandgap semiconductors are increasingly important for bioimaging applications, as they can possess good biocompatibility and host a large range of fluorescent defects spanning the visible to infrared. Gallium nitride is one promising host for photostable fluorophores. In particular, neodymium (Nd)-doped gallium nitride (GaN) shows bright near infrared fluorescence and narrow room temperature linewidth and is therefore a candidate material for fluorescent probes for bioimaging. To explore the conditions necessary to generate biomarkers based on Nd:GaN, this paper reports the room temperature photoluminescence (PL) properties of small ensembles of Nd ions implanted into nanoscale regions of GaN epilayers. The minimum volume of Nd-implanted GaN which can be optically detected in this study is about 8E+4 nm^3 and the minimum detected ensemble of Nd ions is about 4E3, although not all of implanted Nd ions activate as luminescence centers. We show from the PL excitation spectra that the strongest resonant excitation appears at 619 nm, attributed to the 4I9/2 → 4G5/2 (4G7/2) transition in the 4f-shell. We measure the luminescence lifetime to be several tens of microseconds. We also identify the presence of a different excitation mechanism from the resonant excitation when excited below 510 nm (above 2.43 eV).

We developed a new acetalization method of ketones and aldehydes under non-acidic conditions using diazophenanthrenequinone and PdBr2. The formed acetals that have a phenanthrene skeleton withstand under mild acidic conditions. Removal of acetals was successfully proceeded under strong acidic or oxidation conditions using aqueous ceric ammonium nitrate (CAN) to afford corresponding ketones and aldehydes.

In RBS channeling experiments, the slight de-channeling phenomenon of Ga was observed from the depth of about 250 nm in depth behind the surface peak in un-annealed GaN single crystal wafers. In ERDA experiments using 1.8 MeV He^4+ beam, the hydrogen concentration (4.8 x 10^14 cm^-2) in un-annealed GaN was about the twice of that in 900 oC annealed one, suggesting that part of the residual hydrogen was out diffused by annealing. The existence of the minute displacement of Ga in un-annealed GaN was associated with the Ga displacement arising from the complex defect of the residual hydrogen and Ga. This phenomenon corresponds to the appreciable relaxation of Ga atoms toward H proposed by Myer et al. The slight de-channeling phenomena of the Ga atom observed in the RBS channeling experiment disappeared in association with the reduction of hydrogen due to out diffusion of hydrogen in the annealed wafer.

We fabricated circular- and square-shaped pillar arrays with sizes ranging from 100 nm to 2 µm on Pr-implanted GaN epilayers using electron beam lithography, metal deposition, and dry etching techniques. The implantation energy and dose were 100 keV and 1.3×1014 cm-2, respectively. The peak implanted region was estimated to be 24 nm from the top of pillars according to the Monte Carlo simulation code TRIM, and the pillar length was measured to be 510 nm by scanning electron microscopy. Intensity of two emission peaks at 650 nm and 652 nm, which were attributed to 3P0-3F2 transition in the 4f-shell, was analyzed by a home build confocal microscopy. It was shown that the photon emission intensity from Pr3+ ions strongly depended on the nanopillar structures and sizes, and the enhancement more than 20-fold was achieved compared to the non-structured region. The luminescence lifetime was independent of nanopillar structures and sizes. These results indicate that the absorption efficiency of incident photons and the photon extraction efficiency were enhanced by the confinement in nanopillars., 4th QST International Symposium

Lanthanoid (Ln)-doped Gallium Nitride (GaN) have attracted attentions because of their high intensity luminescence and sharp room-temperature (RT) optical linewidth. These superior luminescent properties are quite attractive for the application of single photon source (SPS) which is a key technology for quantum computing, quantum sensing, and quantum key distribution. However, one of the challenges to realize Ln-doped GaN SPS is the long luminescent transition lifetime, resulting in the low photon counts insufficient to optically detect isolated single Ln ions. Confinement of luminescent centers into nanometersized regions is an effective method to enhance their photon emission and we here we show that confinement into GaN nanopillars enhances photon emission from implanted praseodymium (Pr) ions at RT., The 8th International Conference on Nanoscience and Nanotechnology (ICONN2020)

Lanthanoid-doped gallium nitride (GaN) semiconductors have attracted attention because of their high intensity luminescence and sharp room-temperature (RT) optical linewidth. GaN surfaces can be chemically functionalized and nanometer-sized particles are available, opening the door to lifescience applications such as bioimaging and biosensing. Neodymium (Nd)-doped GaN is of strong interest due to its strong near infrared luminescence at 0.9~1.1 µm which is suitable for optical imaging in biological tissues. To realize bioimaging/sensing using Nd-doped GaN nanoparticles, the small ensemble of Nd ions has to be optically detected at RT with high contrast. This paper reports photoluminescence of Nd ions implanted into submicron regions of GaN epilayer and their luminescence properties at RT. The Nd implanted square regions with the side of 250 nm were optically detected. The minimum size which was successfully fabricated and optically detected was 150 nm in this study, which supports further investigations into fluorescent nanoparticles for bioimaging applications. In the presentation, PL spectra, PL excitation spectra, saturation behavior, and luminescent transition lifetime at RT will be discusse, 29th Annual Meeting of MRS-J

In this study, we investigate the photoluminescence (PL) properties of implanted Praseodymium (Pr) ions into GaN at temperatures up to 1200 oC to clarify the effect of implantation temperature on the Pr3+ activation., 23rd International Workshop on Inelastic Ion-Surface Collisions