Process for fabricating thin film semiconductor device

A process of fabricating a thin film semiconductor device, comprising the steps of:

• forming a semiconducting thin film on the surface of an insulating substrate to spread in both a longitudinal direction and a lateral direction;
• laser-annealing the semiconductor thin film by intermittently irradiating a pulsed laser beam formed in a narrow rectangle with a length extending in the longitudinal direction and a width extending in the lateral direction of the insulating substrate to cause crystallizing of the semiconducting thin film;
• and
• integratedly forming thin film transistors, each transistor including the semiconducting thin film as an active layer, with a specific arrangement pitch in the lateral direction;
• wherein said laser annealing step further comprising a step of moving the laser beam relative to the insulating substrate in the lateral direction with a specific movement pitch to form a partially overlapping region at edges of the width of the beam between adjacent region irradiated with the laser beam, the movement pitch in the lateral direction between pulses of the laser beam being set at a value equal to an arrangement pitch of the active layer of the thin film transistors or at a value larger by a factor of an integer than the arrangement pitch of the active layer of the thin film transistors and positioning the substrate before the annealing step so that the overlapping region will be between the active layers of the thin film transistors.