A mask is formed selectively on a crystalline silicon film containing a catalyst element, and an amorphous silicon film is formed so as to cover the mask. Phosphorus is implanted into the amorphous silicon film and the portion of the crystalline silicon film which is not covered with the mask. The silicon films are then heated by rapid thermal annealing (RTA). By virtue of the existence of the amorphous silicon film, the temperature of the crystalline silicon film is increased uniformly, whereby the portion of the crystalline silicon film covered with the mask is also heated sufficiently and the catalyst element existing in this region moves to the phosphorus-implanted, amorphous portion having high gettering ability. As a result, the concentration of the catalyst element is reduced in the portion of the silicon film covered with the mask. A semiconductor device is manufactured by using this portion.
In a manufacturing process of a semiconductor device using a substrate having low heat resistance, such as a glass substrate, there is provided a method of efficiently carrying out crystallization of a semiconductor film and gettering treatment of a catalytic element used for the crystallization by a heating treatment in a short time without deforming the substrate. A heating treatment method of the present invention is characterized in that a light source is controlled in a pulsed manner to irradiate a semiconductor film, so that a heating treatment of the semiconductor film is efficiently carried out in a short time, and damage of the substrate due to heat is prevented.
