Method for producing semiconductor device

A method for producing a semiconductor device, comprising:

• forming a semiconductor layer comprising amorphous silicon on a glass substrate;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, the semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• heating a semiconductor layer comprising amorphous silicon formed on a glass substrate to obtain a crystalline semiconductor layer comprising silicon;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, the crystalline semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• forming an amorphous semiconductor layer comprising silicon on a glass substrate;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, a surface of the amorphous semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface while moving the glass substrate in a height direction thereof so that the irradiated surface always coincides with a focus position of the linear laser beam;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising the steps of:

• heating an amorphous semiconductor layer comprising silicon formed on a glass substrate to obtain a crystalline semiconductor layer comprising silicon;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, a surface of the crystalline semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface while moving the glass substrate in a height direction thereof so that the irradiated surface always coincides with a focus position of the linear laser beam;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• forming an amorphous semiconductor layer comprising silicon on a glass substrate;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, a surface of the amorphous semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface while moving the focus line of the linear laser beam in a height direction of the glass substrate so that the irradiated surface always coincides with a focus position of the linear laser beam;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• heating an amorphous semiconductor layer comprising silicon formed on a glass substrate to obtain a crystalline semiconductor layer comprising silicon;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heated state, a surface of the crystalline semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface while moving the focus line of the linear laser beam in a height direction of the glass substrate so that the irradiated surface always coincides with a focus position of the linear laser beam;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• forming an amorphous semiconductor layer comprising silicon on a glass substrate;
• placing the glass substrate so as to have an inverted-U-shaped convex surface;
• irradiating and scanning, in a heated state, the amorphous semiconductor layer with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the inverted-U-shaped convex surface;
• and then
• cooling the semiconductor layer.

A method for producing a semiconductor device, comprising:

• heating an amorphous semiconductor layer comprising silicon formed on a glass substrate to obtain a crystalline semiconductor layer comprising silicon;
• placing the glass substrate so as to have an inverted-U-shaped convex surface;
• irradiating and scanning, in a heated state, the crystalline semiconductor layer comprising silicon with the linear laser beam having a inverted-U-shaped focus line that approximately coincides with the inverted-U-shaped convex surface;
• and then
• cooling the semiconductor layer.

A liquid crystal electro-optical device producing method comprising:

• forming an amorphous semiconductor layer comprising silicon on a glass substrate;
• placing the glass substrate so as to have a convex surface;
• irradiating and scanning, in a heat state, the amorphous semiconductor layer comprising silicon with the linear laser beam having an inverted-U-shaped focus line that approximately coincides with the convex surface;
• cooling the semiconductor layer after the irradiating and scanning step;
• forming thin film transistors by using the cooled semiconductor layer;
• and
• producing a liquid crystal electro-optical device by using the glass substrate on which the thin film transistors have been formed.

A method for producing a semiconductor device, comprising:

• forming an semiconductor layer comprising silicon on a glass substrate;
• generating a pulse laser light in a laser oscillator;
• shaping said pulse laser light into a linear pulse laser light having a focus line;
• and
• irradiating said linear pulse laser light to said semiconductor layer while moving said linear pulse laser light relatively with respect to said semiconductor layer comprising silicon approximately perpendicularly to longitudinal direction of said linear pulse laser light, to crystallize said semiconductor layer,
• wherein said pulse laser light has an energy variation falling within .+-.3% in terms of 3 .sigma. among laser pulses in said oscillator;
• and
• wherein said focus line approximately coincides with an irregular surface of said glass substrate.

A method for producing a semiconductor device, comprising:

• forming a semiconductor layer comprising silicon on a glass substrate;
• generating a pulse laser beam in a laser oscillator;
• shaping said pulse laser beam into a linear pulse laser beam having a focus line;
• and
• irradiating said linear pulse laser beam to said semiconductor layer while moving said linear pulse laser beam relatively with respect to said semiconductor layer comprising silicon approximately perpendicularly to longitudinal direction of said linear pulse laser beam, to crystallize said semiconductor layer,
• wherein said linear pulse laser beam has an energy distribution satisfying inequalities 0.5L1.ltoreq.L2.ltoreq.L1 and 0.5L1.ltoreq.L3.ltoreq.L1 in a width direction thereof where L1 represents a beam width at an energy density of 0.95, and L1+L2+L3 represents a beam width at an energy density of 0.7 with the L2 and L3 corresponding to both side portions of the beam width, and a maximum energy density of said linear pulse laser beam is assumed to be 1, and
• wherein said focus line approximately coincides with and irregular surface of said glass substrate.

A method for producing a semiconductor device, comprising:

• forming a semiconductor layer comprising silicon on a glass substrate;
• generating a pulse laser light in a laser oscillator;
• shaping said pulse laser light into a laser light into a linear pulse laser light having a focus line;
• and
• irradiating said linear pulse laser light to said semiconductor layer while moving said linear pulse laser light relative to said semiconductor layer comprising silicon approximately perpendicularly to a longitudinal direction of said linear pulse laser light, to crystallize said semiconductor layer, and
• wherein said focus line approximately coincides with an irregular surface of said glass substrate.

A method for producing a semiconductor device, comprising:

• forming a semiconductor layer comprising silicon on a glass substrate;
• generating a pulse laser light in a laser oscillator;
• shaping said pulse laser light into a linear pulse laser light having a focus line;
• and
• irradiating said linear pulse laser light to said semiconductor layer while moving said linear pulse laser light relatively with respect to said semiconductor layer comprising silicon approximately perpendicularly to a longitudinal direction of said linear pulse laser light, to crystallize said semiconductor layer,
• wherein said pulse laser light has an energy variation falling within .+-.3% in terms of 3 .sigma. among laser pulses in said laser oscillator, and
• wherein said glass substrate has a temperature from a temperature higher than room temperature to about 70% of a strain temperature of said glass substrate in said irradiating, and
• wherein said focus line approximately coincides with an irregular surface of said glass substrate.