INTERPRETATION OF OPTICAL DIAGNOSTICS FOR THE ANALYSIS OF LASER CRYSTALLIZATION OF AMORPHOUS SILICON FILMS

The focus of this investigation is on optical diagnostics of melting and solidification during excimer laser crystallization of a-Si. Although optical techniques are effective for probing the laser annealing process, the analysis of the results is not straightforward due to temperature variation of the optical properties, phase change, and interference effects. These effects are clarified by analyzing the front and back, s- and p-polarized reflectivity traces at the lambda=633-nm and 1,520-nm laser wavelengths. Ellipsometry was utilized to measure the temperature-dependent spectral optical properties of the deposited 50-nm a-Si films. Spectral optical properties of laser-annealed poly-silicon were also measured at room temperature. These optical properties were used in the optical models constructed for the melting and solidification processes. Comparison with the experimental results unveiled evidence of spontaneous volumetric nucleation for laser fluences sufficiently high to impart complete melting of the a-Si film.     

Application of two immunochromatographic test kits to screening of four kinds of allergic substances in imported foods

We tested for four kinds of allergic substances (egg, milk, wheat and peanuts) in 52 imported processed foods using immunochromatographic test kits (ITK). ELISA was also employed to confirm the effectiveness of the ITK. Among 92 data from 23 samples, allergic substances were detected in 9 cases with one kind of ITK, but not with the ELISA test. Among 116 data from 29 samples, 6 were negative with one kind of ITK and but positive with the other ITK. These results suggested that these 4 kinds of allergic substances in imported foods can be detected by using a double-check method with two kinds of ITK.