Thin film processing method and thin film processing apparatus including controlling the cooling rate to control the crystal sizes

摘要

A thin film processing method for processing the thin film by irradiating an optical beam to the thin film. A unit of the irradiation of the optical beam includes a first and a second optical pulse irradiation to the thin film, and the unit of the irradiation is carried out repeatedly to process the thin film. The first and the second optical pulse have pulse waveforms different from each other. Preferably, a unit of the irradiation of the optical beam includes the a first optical pulse irradiated to the thin film and a second optical pulse irradiated to the thin film starting substantially simultaneous with the first optical pulse irradiation. In this case, the relationship between the first and the second optical pulse satisfies (the pulse width of the first optical pulse)(the optical pulse of the second optical pulse) and (the irradiation intensity of the first optical pulse)≧(the irradiation intensity of the second optical pulse). A silicon thin film with a small trap state density can be formed by the optical irradiation.