Beam irradiation apparatus, beam irradiation method, and method for manufacturing semiconductor device

A beam irradiation apparatus comprising:

• means for scanning an energy beam output continuously on an irradiated object;
• and
• means for controlling a position of the irradiated object so that the beam is irradiated to an outside of an element-forming region on the irradiated object in positions where the beam starts to be scanned and where the beam ends to be scanned,
• wherein the means for scanning has a specular body;
• wherein the specular body is fixed to a shaft so as to be arranged on an optical axis of the beam;
• and
• wherein the specular body rotates using the shaft as a center.

A beam irradiation method comprising:

• irradiating while scanning an energy beam output continuously and an irradiated object relatively,
• wherein the irradiated object is processed by reflecting the beam on a plurality of specular bodies;
• wherein relative positions of the energy beam and the irradiated object are controlled for every surface of the plurality of the specular bodies;
• and
• wherein the beam is irradiated to an outside of an element-forming region with the irradiated object formed in positions where the beam starts to be irradiated and where the beam ends to be irradiated.

A method for manufacturing a thin film transistor comprising the steps of:

• forming a crystalline semiconductor film by irradiating an energy beam output continuously while scanning the energy beam to a semiconductor film;
• forming a gate electrode over the crystalline semiconductor film;
• and
• forming an impurity region in the crystalline semiconductor film using the gate electrode as a mask,
• wherein a scanning direction of the beam changes outside an element-forming region with the semiconductor film formed.

A method for manufacturing a thin film transistor comprising the steps of:

• forming a crystalline semiconductor film by irradiating an energy beam output continuously while scanning the energy beam to a semiconductor film;
• forming a gate electrode over the crystalline semiconductor film;
• and
• forming an impurity region in the crystalline semiconductor film using the gate electrode as a mask,
• wherein the beam is irradiated to an outside of the element-forming region with the semiconductor film formed in positions where the beam starts to be irradiated and where the beam ends to be irradiated.

A method for manufacturing a semiconductor device comprising the steps of:

• forming a semiconductor film over a substrate;
• crystallizing the semiconductor film by irradiating an energy beam output continuously while scanning the energy beam to the semiconductor film;
• forming a plurality of semiconductor islands by patterning the crystallized semiconductor film;
• forming a first circuit using one of the plurality of semiconductor islands over the substrate as an active layer;
• and
• forming a second circuit using another one of the plurality of semiconductor islands over the substrate as the active layer,
• wherein a region irradiated while changing a scanning direction of the energy beam when crystallizing the semiconductor film by the energy beam is not included in the semiconductor islands constituting the first circuit and the second circuit.