Laser processing apparatus having beam expander

A laser processing apparatus for irradiating a semiconductor layer with a laser beam, said apparatus comprising:

• a laser device for emitting a laser beam having a cross section;
• expanding means for expanding the laser beam only in a lengthwise direction of the cross section wherein an intensity distribution of the laser beam in the lengthwise direction is homogenized by said expanding means, said expanding means comprising at least a cylindrical lens array and a convex lens which condenses the laser beam only in the lengthwise direction;
• condensing means for condensing the expanded laser beam only in a widthwise direction of the cross section;
• supporting means for supporting the substrate;
• moving means for moving said substrate in a widthwise direction of the cross section of the expanded laser beam.

A laser processing apparatus comprising:

• a laser device for emitting a laser beam having a cross section;
• expanding means for expanding the laser beam only in a lengthwise direction of the cross section wherein an intensity distribution of the laser beam in the lengthwise direction is simultaneously homogenized by said expanding means;
• an optical means for making a length of the cross section of the expanded laser beam constant during the propagation thereof, said length being at least 10 cm;
• supporting means for supporting a substrate to be treated with the expanded laser beam;
• moving means for moving said substrate in a widthwise direction of the cross section of the expanded laser beam so that an entire surface of said substrate can be treated with the expanded laser beam.

A laser processing apparatus for irradiating a semiconductor layer with a laser beam said apparatus comprising:

• a laser device for emitting a laser beam having a cross section;
• expanding means for expanding the laser beam only in a lengthwise direction of the cross section wherein an intensity distribution of the laser beam in the lengthwise direction is homogenized by said expanding means, said expanding means comprising at least a first cylindrical lens array and a first convex lens which condenses the laser beam only in the lengthwise direction:
• condensing means for condensing the expanded laser beam only in a widthwise direction of the cross section, said condensing means comprising a second cylindrical lens array and a second convex lens which condenses the laser beam only in the widthwise direction;
• supporting means for supporting the substrate;
• moving means for moving said substrate in a widthwise direction of the cross section of the expanded laser beam so that an entire surface of said substrate can be treated with the expanded laser beam.

A laser processing apparatus for irradiating a semiconductor layer with a laser beam, said apparatus comprising:

• a laser device for emitting a laser beam having a cross section;
• expanding means for expanding the laser beam only in a lengthwise direction of the cross section wherein an intensity distribution of the laser beam in the lengthwise direction is homogenized by said expanding means, said expanding means comprising at least a first cylindrical lens array which comprises a plurality of cylindrical lenses arranged in the lengthwise direction and a first convex lens which condenses the laser beam only in the lengthwise direction;
• condensing means for condensing the expanded laser beam only in a widthwise direction of the cross section, said condensing means comprising a second cylindrical lens array which comprises a plurality of cylindrical lenses arranged in the widthwise direction and a second convex lens which condenses the laser beam only in the widthwise direction;
• supporting means for supporting the substrate;
• and
• moving means for moving said substrate in a widthwise direction of the cross section of the expanded laser beam so that an entire surface of said substrate can be treated with the expanded laser beam.