SEMICONDUCTOR CRYSTAL GROWING METHOD AND SEMICONDUCTOR MANUFACTURING DEVICE

摘要

PURPOSE: To form a polysilicon thin film composed of crystal grains having high uniformity of grain sizes by deciding the size of crystal areas based on the thickness of an amorphous semiconductor thin film so that one crystal nucleus can be formed in each crystal area and selectively imparting crystallizing energy to the crystal areas having the decided size. CONSTITUTION: An amorphous silicon thin film 2 having a thickness of 100nm is deposited on an insulating substrate 1 formed by depositing a silicon oxide film on the surface of a silicon substrate by using the LPCVD method. The thin film 2 is irradiated with a laser beam 3 shaped so that the diameter of the beam 3 can become about 100nm on the surface of the substrate 1. It has been learnt from tests carried out by changing the thickness of the thin film 2 in various ways that crystal grains of a uniform diameter can be obtained when crystal nuclei are formed in areas having sizes which are equal to or smaller than the five time of the thickness. Since the diameter of the laser beam 3 is made nearly equal to the thickness of the thin film 2, crystal nuclei 4 composed of single crystal grains are formed in the area irradiated with the beam 3.