Method of manufacturing polycrystalline silicon layer, and method of manufacturing transistor having the polycrystalline silicon layer

1. A method of manufacturing a polycrystalline silicon layer, the method comprising:

providing a crystallization substrate, the crystallization substrate having an amorphous silicon layer on a first substrate;

providing a reflection substrate, the reflection substrate having a first region with a reflection panel therein and a second region without the reflection panel;

disposing the crystallization substrate and the reflection substrate on one another; and

selectively crystallizing the amorphous silicon layer by directing a laser beam through the crystallization substrate and onto the reflection substrate, and reflecting the laser beam from the reflection panel back through the crystallization substrate.

2. The method as claimed in claim 1 , wherein the crystallization substrate has a buffer layer between the first substrate and the amorphous silicon layer.

3. The method as claimed in claim 2 , wherein the first substrate includes a transparent material, the laser beam passing through the first substrate.

4. The method as claimed in claim 3 , wherein the first substrate is a glass substrate.

5. The method as claimed in claim 1 , wherein the reflection substrate includes:

a second substrate, the reflection panel being a pattern on the second substrate; and

a protection film arranged on the second substrate to cover the reflection panel.

6. The method as claimed in claim 5 , wherein the second substrate includes a transparent material, the laser beam passing through the transparent material.

7. The method as claimed in claim 6 , wherein the second substrate is glass or quartz.

8. The method as claimed in claim 5 , wherein the reflection panel includes a metal that is capable of reflecting the laser beam, the laser beam being reflected from the metal to the crystallization substrate.

9. The method as claimed in claim 8 , wherein the metal has a reflectance of 50% or higher with respect to the laser beam.

10. The method as claimed in claim 5 , wherein the protection film includes an oxide, a nitride, or an organic matter, the laser beam passing through the protection film.

11. The method as claimed in claim 10 , wherein:

the protection film is a single layer formed of an oxide, a nitride, or an organic material, or

the protection film is a plurality of layers, each layer being formed of an oxide, a nitride, or an organic material.

12. The method as claimed in claim 1 , wherein, in the disposing of the crystallization substrate and the reflection substrate on one another, the crystallization substrate and the reflection substrate are brought into contact with each other so that the amorphous silicon layer faces the reflection panel.

13. The method as claimed in claim 1 , wherein selectively crystallizing the amorphous silicon layer comprises:

directing the laser beam in a direction from the crystallization substrate toward the reflection substrate; and

forming a polycrystalline silicon layer by crystallizing a first area of the amorphous silicon layer corresponding to the first region of the reflection substrate as the laser beam directed toward the reflection substrate is reflected by the reflection panel.

14. The method as claimed in claim 13 , wherein the forming of the polycrystalline silicon layer comprises:

allowing the laser beam to pass through the first area of the amorphous silicon layer; and

crystallizing the first area of the amorphous silicon layer by using the reflection panel in the first region of the reflection substrate to reflect the laser beam passing through the first area of the amorphous silicon layer onto the first area of the amorphous silicon layer.

15. The method as claimed in claim 13 , further comprising allowing the laser beam to pass through a second area of the crystallization substrate and the second region of the reflection substrate, wherein the second area of the amorphous silicon layer is not crystallized and remains as the amorphous silicon layer after the laser beam passes through the second area of the amorphous silicon layer corresponding to the second region of the reflection substrate.

16. The method as claimed in claim 1 , wherein the laser beam is scanned in a direction perpendicular to the reflection panel.

17. The method as claimed in claim 1 , further comprising disassembling the crystallization substrate and the reflection substrate, after selectively crystallizing the amorphous silicon layer.

18. A method of manufacturing a transistor, the method comprising:

providing a crystallization substrate, the crystallization substrate having an amorphous silicon layer on a first substrate;

providing a reflection substrate, the reflection substrate having a first region with a reflection panel therein and a second region without the reflection panel;

disposing the crystallization substrate and the reflection substrate on one another;

forming a polycrystalline silicon layer by selectively crystallizing the amorphous silicon layer by directing a laser beam through the crystallization substrate and onto the reflection substrate, and reflecting the laser beam from the reflection panel back through the crystallization substrate; and

forming a channel region and source and drain regions in the polycrystalline silicon layer.

19. The method as claimed in claim 18 , further comprising:

disassembling the crystallization substrate and the reflection substrate, after selectively crystallizing the amorphous silicon layer.

20. The method as claimed in claim 18 , further comprising:

forming a gate insulation film on the crystallization substrate to cover the polycrystalline silicon layer;

forming a gate electrode on the gate insulation film, the gate electrode corresponding to the channel region of the polycrystalline silicon layer;

forming an interlayer insulation film on the gate insulation film to cover the gate electrode; and

forming a source electrode and a drain electrode which are disposed on the interlayer insulation film and electrically connected to the source region and the drain region of the polycrystalline silicon layer, respectively.

21. The method as claimed in claim 18 , wherein forming the polycrystalline silicon layer comprises:

directing the laser beam in a direction from the crystallization substrate toward the reflection substrate; and

crystallizing a first area of the amorphous silicon layer corresponding to the first region of the reflection substrate as the laser beam directed toward the reflection substrate is reflected by the reflection panel.

22. The method as claimed in claim 21 , further comprising allowing the laser beam to pass through a second area of the crystallization substrate and the second region of the reflection substrate, wherein the second area of the amorphous silicon layer is not crystallized and remains as the amorphous silicon layer after the laser beam passes through the second area of the amorphous silicon layer corresponding to the second region of the reflection substrate.