| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a satisfactory polycrystalline semiconductor thin film by performing one time irradiation of a specified energy in a first process, and performing at least one time irradiation of energy which is equal to or lower than the specified energy and several times irradiation, while irradiation energy is gradually decreased, in a second process. SOLUTION: A silicon oxide film is deposited as a substratum protecting layer 20 on a heated substrate 30. Continuously, an amorphous semiconductor film 10 is formed. The amorphous semiconductor film is subjected to pulsed laser irradiation. At this time, irradiation of energy slightly lower than a threshold level of fine crystallization is performed. In a first process, the amorphous film is changed to a polycrystalline film, having large crystal grains by the fine crystallizing energy. A second process is performed subsequent to the first process and is made a process, where at least one time irradiation is performed by energy which is equal to or lower than the specified energy of the first process. Several times of irradiation is further performed, while irradiated energy of the second process is gradually decreased.</p> |
