To provide a semiconductor device having a function equivalent to that of
IGFET, an activation layer is formed by a crystal silicon film
crystallized by using a catalyst element helping promote crystallization
and a heating treatment is carried out in an atmosphere including a
halogen element by which the catalyst element is removed, the activation
layer processed by such steps is constituted by a peculiar crystal
structure and according to the crystal structure, a rate of incommensurate
bonds in respect of all of bonds at grain boundaries is 5% or less
(preferably, 3% or less).
