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In this paper we report the direct observations of the lateral crystallizing process induced by single-pulse excimer laser annealing (ELA) for the first time. In order to modulate a beam profile on amorphous-silicon thin films intentionally, a mask projection type ELA system was used. Incorporating an optical microscope, a high speed gated image intensifier and a streak camera imaging system, a novel measuring system successfully revealed the dynamic lateral motion of liquid-solid Si interface with micrometer spatial resolution and nanosecond time domain. Furthermore, it was confirmed that the obtained streak images were well consistent with the simulated beam profiles to induce lateral growth crystallization, and the lateral solidifying velocity of 13m/sec was directly measured when 4μm-long grain had grown by phase-modulated excimer laser annealing (PMELA) method.

We have developed an advanced sample structure for large-grain growth by excimer-laser crystallization of Si. More than 10 μm long grains were grown laterally in a 50 nm thick Si layer by phase-modulated excimer-laser annealing. A photosensitive SiO x capping layer prepared using a conventional plasma-enhanced chemical vapor deposition apparatus enables this longer lateral growth with lower irradiated intensity of laser light than those with the conventional SiO 2 capping layer.

We have successfully demonstrated chemical vapor deposition of a silica film in which some of oxygen atoms of the pure silica network are replaced to methylene (-CH 2 ,) groups. The as-deposited film was thermally unstable owing to the unwanted decomposition reaction of the methylene group with the dense H 2 O in the film. It was found that the film could be dehydrated without decomposition of the methylene group by low temperature anncaling in a XeF 2 ambient. The dehydrated film showed not only good insulating and low-k characteristics (resistivity of 10 15 Ω cm, breakdown field of 3.3 MV/cm, and k of 2.8), but also good thermal properties, such as good thermal stability and high thermal conductivity.