Display device and method of manufacturing the same

A method of manufacturing a display device, the method comprising:

• forming an amorphous silicon layer on a substrate on which a first region and a second region spaced from each other are defined;
• partially etching the second region of the amorphous silicon layer;
• crystallizing the amorphous silicon layer to form a polycrystalline silicon layer;
• etching all regions of the polycrystalline silicon layer except for the first region and the second region to form a first polycrystalline silicon pattern and a second polycrystalline silicon pattern in the first region and the second region, respectively;
• forming a first gate insulating layer on the first polycrystalline silicon pattern and the second polycrystalline silicon pattern;
• and
• forming a first gate electrode and a second gate electrode that overlap the first polycrystalline silicon pattern and the second polycrystalline silicon pattern, respectively, on the first gate insulating layer.

A method of manufacturing a display device, the method comprising:

• forming a buffer layer on a substrate on which a first region and a second region spaced from each other are defined;
• partially etching the first region of the buffer layer;
• forming an amorphous silicon layer on the buffer layer;
• polishing the amorphous silicon layer;
• crystallizing the amorphous silicon layer to form a polycrystalline silicon layer;
• etching all regions of the polycrystalline silicon layer except for the first region and the second region to form a first polycrystalline silicon pattern and a second polycrystalline silicon pattern in the first region and the second region, respectively;
• forming a first gate insulating layer on the first polycrystalline silicon pattern and the second polycrystalline silicon pattern;
• and
• forming a first gate electrode and a second gate electrode that overlap the first polycrystalline silicon pattern and the second polycrystalline silicon pattern, respectively, on the first gate insulating layer.