Method for forming amorphous thin film

A method for forming an amorphous thin film, the method comprising:

• forming a seed layer on a surface of a base by supplying aminosilane-based gas on the base;
• and
• forming the amorphous thin film having a predetermined thickness on the seed layer,
• wherein said forming the amorphous thin film comprises:
• forming a first boron-doped amorphous thin film having a first thickness on the seed layer;
• and
• forming a second boron-doped amorphous thin film having a second thickness on the first boron-doped amorphous thin film, and
• wherein a first source gas used in said forming the first boron-doped amorphous thin film includes boron-based gas and silane-based gas and be supplied to the seed layer, and a second source gas used in said forming the second boron-doped amorphous thin film includes the boron-based gas, the second source gas being different from the first source gas and being supplied to the first boron-doped amorphous thin film.