The effect of stress in silicon nitride films on boron diffusion of silicon has been studied. During annealing in nitrogen, the degree of the retardation in boron diffusion becomes larger as the temperature becomes lower and the thickness of nitride films increases. On the other hand, boron diffusion of Si covered with very thin nitride films is enhanced for long diffusion times. These results suggest that nitride film stress makes the region near the surface of the silicon substrate compressed and changes vacancy and interstitial concentrations.The various thin films used in LSI usually develop stress during the thermal process and the stress causes problems such as leak current and generation of dislocations in large scale integrated (LSI) devices. Moreover, accurate control of boron diffusion %vith doses of 1012 to 1013/cm 2 in silicon covered with various films is essential for channel doping with the scaling down of LSI. Therefore, it is necessary to investigate the effects of stress in the films on the substrate and on dopant diffusion in the silicon substrate.Silicon nitride (Si3N4) films used as oxidation resistant masks and dielectric layers are highly stressed, 1-4 so the effect of stress in the Si3N4 films on dopant diffusion is of interest. With respect to this topic, Mizuo et al. ~ and Ahn et al.6 reported that diffusion of dopant in float zone (FZ) silicon under Si3N4 films was retarded compared with that under silicon dioxide (SiO2) films covered with nitride films. However, Mizuo et aI. did not take into account the effect of stress in deposited Si~N~ films during heat-treatment. Since Ahn et al. deposited off-stoiehiometrie Si3N4films on both sides of the samples to prevent bending of the substrates, it seems that they investigated the effect of the chemical reaction between off-stoiehiometric nitride films and the surface of the Si substrate on the diffusion of phosphorus in FZ-Si, but not on the stress in SiaN4 films. Their experimental conditions ~' 6 were also restricted in terms of the thickness of Si3N 4 films, time, and temperature of diffusion. Moreover, their analysis based on only the penetration depth monitored by a staining technique was not sufficient.In the present paper, we have investigated the effect of stress in deposited Si3N~ films on the diffusion of boron in FZ-Si. The thickness of Si3N4 films, time, and temperature of diffusion were varied in a wide range. In addition to the Si3N4/Si structure, boron diffusion of Si under the area masked with double-layered SiO2-Si3N4 films and the area without any films was also performed to clarify the effect of SigN4 film stress on the point defect generation. Boron profiles were measured by secondary ion mass spectroscopy (SIMS). We found that diffusion of boron in FZ-Si under Si3N, films had anomalous characteristics. These results are discussed in terms of point defect concentration. ExperimentalThe substrates used were p-type (100) FZ-Si wafers with resistivities of 3 to 5 f~-em. The use of FZ-Si is essential for avoiding the accompa...

Hybrid nanocomposite particles composed of a gold core coated with a europium(iii)-chelate fluorophore-doped silica shell (AuNPs@SiO-Eu) have been synthesized and applied as antibody labels in lateral flow immunoassay (LFIA) devices for the determination of human thyroid stimulating hormone (hTSH). Labeling of monoclonal anti-hTSH antibodies with AuNPs@SiO-Eu nanocomposites allows for both colorimetric and fluorometric observation of assay results on LFIA devices, relying on visible light absorption due to the localized surface plasmon resonance of the Au-core and the fluorescence emission of the Eu(iii)-chelate-modified shell under UV hand lamp irradiation (365 nm), respectively. The possibility for a dual signal readout provides an attractive alternative for LFIAs: instantaneous naked eye observation of the AuNP colorimetric signal as in conventional LFIAs for hypothyroidism detection, and more sensitive fluorescence detection to assess hyperthyroidism. The limits of detection (LOD) for naked eye observation of LFIA devices are 5 μIU mL and 0.1 μIU mL for the colorimetric and fluorimetric detection, respectively. Using the fluorescence detection scheme in combination with a smartphone and digital color analysis, a quantitative linear relationship between the red intensity and the logarithmic concentration of hTSH was observed (R = 0.988) with an LOD of 0.02 μIU mL. Finally, LFIA devices were effectively applied for detecting hTSH in spiked diluted human serum with recovery values between 100-116%.

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Deformation experiments for 20(MgO or Na 2 O)-20Al 2 O 3-60SiO 2 glasses were performed in simple shear geometry at 1.5-5 GPa and room temperature. An abrupt change in the thinning rate and the turning of the birefringence azimuth at a shear strain of γ = 1-2 indicate a transition of deformation mechanism from uniaxial compression aided by densification to shear flow in the glasses. The high-dense magne-How to cite this article: Osada K, Yamada A, Ohuchi T, Yoshida S, Matsuoka J. Transition in deformation mechanism of aluminosilicate glass at high pressure and room temperature.

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