Crystallinity evaluation of a thin-film polysilicon

Crystallinity evaluation of a thin-film polysilicon

This is an analysis example of a thin film polysilicon. Electron mobility of polysilicon is higher than that of amorphous silicon so that thin film polysilicon has been used a liquid crystal display, and a solar cell. Polysilicon is produced by heating the amorphous silicon. In the process of changing from the amorphous silicon into polysilicon, the Rama spectrum changes and the Raman peak of higher crystalline polysilicon apears at a higher wavenumber so that RAMANtouch can be used for the evalustion of thin film polysilicon. This sample was produced by irradiating the excimer laser to the thin film amorphous silicon of about 300nm in thickness. The boundary in two regions formed by the different production conditions (condition 1 and condition 2) has been observed. The difference in production conditions and difference in crystallinity due to unevenness of the laser illumination used to form the polysicon are clearly observed.