Manufacturing method for a semiconductor device and heat treatment method therefor

A manufacturing method for a semiconductor device, comprising:

• forming a semiconductor layer over a substrate;
• forming an insulating layer over the semiconductor layer wherein said semiconductor layer includes a region to become at least a channel region of a thin film transistor;
• forming a conductive layer over the semiconductor layer with the insulating layer interposed therebetween;
• selectively heating the semiconductor layer by using a heat source capable of radiating an incoherent electromagnetic wave within a wavelength band ranging at least from a visible light band to an infrared band;
• and
• etching said conductive layer after the selective heating of the semiconductor layer to form a gate electrode over the semiconductor layer,
• wherein said conductive layer extends beyond a periphery of the semiconductor layer at least when the selective heating of the semiconductor layer is performed.

A manufacturing method for a semiconductor device, comprising:

• heating an entire surface of a substrate by radiation heating from a first heat source;
• forming a semiconductor layer over the substrate;
• forming an insulating layer on the semiconductor layer wherein said semiconductor layer includes a region to become at least a channel region of a thin film transistor;
• forming a conductive layer on the insulating layer;
• selectively heating the semiconductor layer by using a second heat source capable of radiating an electromagnetic wave within a wavelength band ranging at least from a visible light band to an infrared band;
• and
• etching said conductive layer after the selective heating of the semiconductor layer to form a gate electrode over the semiconductor layer,
• wherein an entire top surface of the semiconductor layer is covered by the conductive layer when the semiconductor layer is selectively heated.