The electrical conduction of self-assembled monolayers (SAMs) made from conjugated molecules was measured using conductive atomic force microscopy (AFM), with a focus on the molecular structural effect on the electrical conduction. For phenylene oligomer SAMs, resistances through the monolayers increased exponentially with increases in molecular length and the decay constants of transconductance β were ca. 0.35 to 0.5 Å-1. Using an insertion technique into insulative alkanethiol SAMs, we successfully obtained single molecular resistance of terphenyl methanethiol at ca. 5.4 × 1010 Ω. We further investigated the influence of applied load on the resistances. The resistances through terphenyl SAMs increased with increases in the applied load up to 15 nN. When two or three methylene spacers were introduced between the sulfur and terphenyl groups in a series of terphenyl derivatized thiols, the monolayer resistances and β values increased extraordinarily. One explanation is that the addition of methylene spacers changed the location of the molecular orbital as a result of MOPAC calculation.

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Recrystallization of polycrystalline silicon (poly-Si) film by excimer laser annealing (ELA) is discussed by considering the experimental results that the three stages of nucleation, textured grain growth and secondary grain growth were observed. Although the phenomenon of nucleation in the amorphous silicon (a-Si) is understood by considering crystallization from the super cooled liquid, the growth mechanisms of the textured grain and secondary grain are not understood by this, because the melting point of poly-Si which has already been formed on the entire surface during these growth stages is higher than that of a-Si. The recrystallization mechanism considering the dislocation movement is introduced to investigate the present phenomenon. It also clarifies the reason why secondary grain growth occurs under the critical conditions of laser irradiation energy and shot number. The feasibility of nucleation through the super cooled liquid is also discussed.

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Characteristics of polycrystalline silicon (poly-Si)film prepared by excimer laser annealing was examined. The crystallinity increases as increasing the laser energy density and the number of shot. The secondary grain growth occurs at the laser energy density and the number of shot larger than the critical values. The crystallinity of the poly-Si with dehydrogenation prior to the laser irradiation is better than that with non-dehydrogenation. Its surface roughness becomes same as or better than that with non-dehydrogenation.