Ultrafast measurements of photoexcited carrier dynamics within a 60 nm subsurface of a crystalline silicon wafer were carried out using subpicosecond transient reflectivity. A uv pump light was employed to restrict carrier generation to occur within the subsurface by direct interband transitions. Carrier diffusion was found to be suppressed in the subsurface region of the intrinsic silicon wafer. For ion-implanted silicon wafers, heat was generated within a few picoseconds after the laser irradiation. By scanning a partially ion-implanted silicon wafer, the two-dimensional image was obtained, which showed that time-resolved imaging can separately map photoexcited carrier density and transient temperature rise. The possibility of three-dimensional process monitoring was considered as well.

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A quasi-elastic laser scattering (QELS) method was applied to monitoring the capillary wave frequencies at a water/ nitrobenzene interface. A digital spectrum analyzer was adopted to improve the time resolution of the QELS method. As a result, each power spectrum could be obtained in 1 s and saved in an additional 1 s. The equipment was checked by monitoring capillary wave frequencies at a water/ nitrobenzene interface covered with a monolayer of dipalmitoylphosphatidylcholine (DPPC), i.e. changes of interfacial tension caused by the formation of the monolayer at the interface were detected. The equipment was then applied to a chemical oscillation system. It was found that the interface of the chemical oscillation system was covered with a high density membrane during the chemical oscillation.

Erratum: Particulates reduction in laserablated YBa2Cu3O7−δ thin films by laserinduced plume heating [Appl.

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