Crystallization apparatus, crystallization method, device and phase modulation element
View Patent ↗The present invention comprises a light modulation optical system having a first element which forms a desired light intensity gradient distribution to an incident light beam and a second element which forms a desired light intensity minimum distribution with an inverse peak shape to the same, and an image formation optical system which is provided between the light modulation optical system and a substrate having a polycrystal semiconductor film or an amorphous semiconductor film, wherein the incident light beam to which the light intensity gradient distribution and the light intensity minimum distribution are formed is applied to the polycrystal semiconductor film or the amorphous semiconductor film through the image formation optical system, thereby crystallizing a non-crystal semiconductor film. The pattern of the first element is opposed to the pattern of the second element.
1. A crystallization method comprising:
illuminating with an incident light beam a light modulation optical system which has a first element forming a light intensity distribution of a V-shaped light intensity gradient distribution with the minimum oriented along a Y direction to implement crystal growth in a lateral direction along a light intensity gradient from a crystal core and a second element forming a light intensity minimum distribution with an inverse peak shape with the minimum oriented along a X direction to position a first occurrence of solidification on an irradiated surface at a position where light intensity of the V shaped light intensity gradient distribution and the light intensity minimum distribution with an inverse peak shape are both at a minimum intensity,
said first element comprising a plurality of cells including a first phase-modulation area and a second phase-modulation area where an area share ratio of the first phase-modulation area varies along a predetermined direction to decrease said light intensity toward the position where the light intensity is minimum; and
irradiating a polycrystalline semiconductor film or an amorphous semiconductor film with the incident light beam having a light intensity distribution with which a light intensity distribution pattern is generated by the first element and the second element, in an irradiated surface to melt an irradiated region through an image formation optical system provided between the light modulation optical system and a substrate having the film, thereby crystallizing the polycrystalline semiconductor film or the amorphous semiconductor film, such that a position corresponding to an irradiation position where light intensity of the light intensity distribution is lowest is first solidified when incidence of the light beam is interrupted, and the solidification position is moved and crystallized along the V-shaped light intensity gradient distribution.
2. The crystallization method according to claim 1 , wherein the light beam having the predetermined light intensity distribution forms a laser beam of the V-shaped light intensity gradient distribution and then forms a laser beam of the combined light intensity distribution of a laser beam of a minimum distribution in which the light intensity of the V-shaped light intensity gradient distribution is minimum.
3. The crystallization method according to claim 1 , wherein the light beam having the predetermined light intensity distribution forms a laser beam of the V-shaped light intensity gradient distribution and a laser beam having a minimum light intensity of the light intensity distribution with the inverse peak shape, and then forms a laser beam of the combined light intensity distribution of a laser beam of the minimum distribution in which the light intensity is minimum and a laser beam of the V-shaped light intensity gradient distribution.
4. The crystallization method according to claim 1 , wherein the light beam having the predetermined light intensity distribution is a laser beam which forms on a surface of a processed substrate a laser beam of a combined light intensity distribution of both a laser beam of the V-shaped light intensity gradient distribution and a laser beam of a minimum distribution in which a light intensity of the light intensity distribution with the inverse peak shape is minimum.
5. A crystallization method comprising:
illuminating with an incident light beam a light modulation optical system which has an element having a combined pattern obtained from a first pattern forming a light intensity distribution of a V-shaped light intensity gradient distribution with the minimum oriented along a Y direction to implement crystal growth in a lateral direction along a light intensity gradient from a crystal core and a second pattern forming a light intensity minimum distribution with an inverse peak shape with the minimum oriented along a X direction to position a first occurrence of solidification on an irradiated surface at a position where light intensity of the V shaped light intensity gradient distribution and the light intensity minimum distribution with an inverse peak shape are both at a minimum intensity,
said first pattern comprising at least one row of cells including a first phase-modulation area and a second phase-modulation area where a size of the first phase-modulation area varies along the row and decreases said light intensity toward the position where the light intensity is minimum; and
irradiating a polycrystalline semiconductor film or an amorphous semiconductor film with the incident light beam having a light intensity distribution with which a light intensity distribution pattern is generated by the first pattern and the second pattern, in an irradiated surface to melt an irradiated region through an image formation optical system provided between the light modulation optical system and a substrate having the film, thereby crystallizing the polycrystalline semiconductor film or the amorphous semiconductor film, such that a position corresponding to an irradiation position where light intensity of the light intensity distribution is lowest is first solidified when incidence of the light beam is interrupted, and the solidification position is moved and crystallized along the V-shaped light intensity gradient distribution.
6. The crystallization method according to claim 5 , wherein the light beam having the predetermined light intensity distribution forms a laser beam of the V-shaped light intensity gradient distribution and then forms a laser beam of the combined light intensity distribution of a laser beam of a minimum distribution in which the light intensity of the V-shaped light intensity gradient distribution is minimum.
7. The crystallization method according to claim 5 , wherein the light beam having the predetermined light intensity distribution forms a laser beam of the V-shaped light intensity gradient distribution and a laser beam having a minimum light intensity of the light intensity distribution with the inverse peak shape, and then forms a laser beam of the combined light intensity distribution of a laser beam of the minimum distribution in which the light intensity is minimum and a laser beam of the V-shaped light intensity gradient distribution.
8. The crystallization method according to claim 5 , wherein the light laser beam having the predetermined light intensity distribution is a laser beam which forms on a surface of a processed substrate a laser beam of a combined light intensity distribution of both a laser beam of the V-shaped light intensity gradient distribution and a laser beam of a minimum distribution in which a light intensity of the light intensity distribution with the inverse peak shape is minimum.
9. The crystallization method according to claim 5 , wherein said size of the first phase-modulation area is largest in a center of the row.
10. The crystallization method according to claim 5 , wherein said size of the first phase-modulation area decreases in a direction along the row from the center.