Slot die coating apparatus and coating method using the same
A slot die coater planarizing an upper surface of an encapsulation layer and a coating method using the same. The slot die coater includes a slit nozzle configured to supply a coating solution. The slit nozzle includes a hole vertically penetrating a center portion thereof, a first bottom surface disposed at a movement direction side of the slit nozzle with reference to the hole, and a second bottom surface disposed at an opposite direction side of the movement direction of the slit nozzle with reference to the hole. A width of the first bottom surface is different from the width of the second bottom surface.
1. A slot die coater comprising:
a slit nozzle configured to supply a coating solution onto a substrate,
wherein:
the slit nozzle comprises:
a hole vertically penetrating a center portion thereof;
a first bottom surface positioned at a movement direction side of the slit nozzle with reference to the hole; and
a second bottom surface positioned at an opposite direction side of the movement direction of the slit nozzle with reference to the hole;
the first bottom surface and the second bottom surface are flat and parallel to an upper surface of the substrate;
the width of the first bottom surface is less than the width of the second bottom surface; and
both the front side and the rear side of a lower portion of the slit nozzle are tapered toward the first and second bottom surfaces.
2. The slot die coater of claim 1 wherein a distance between the first bottom surface and the substrate is greater than a distance between the second bottom surface and the substrate.
3. The slot die coater of claim 1 , wherein:
the first bottom surface has a width of 0.1 mm to 0.9 mm; and
the second bottom surface has a width of 0.1 mm to 0.9 mm.
4. A coating method comprising:
mounting a substrate on a stage; and
moving a slit nozzle over the substrate while supplying a coating solution to the substrate to form a coating layer,
wherein the slit nozzle comprises:
a hole vertically penetrating a center portion thereof;
a first bottom surface disposed at a movement direction side of the slit nozzle with reference to the hole; and
a second bottom surface disposed at an opposite direction side of the movement direction of the slit nozzle with reference to the hole;
the first bottom surface and the second bottom surface are flat and parallel to an upper surface of the substrate;
the width of the first bottom surface is different from the width of the second bottom surface; and
during moving of the slit nozzle, a distance between the second bottom surface and the substrate is substantially the same as the thickness of the coating layer.
5. The coating method of claim 4 , wherein, during moving of the slit nozzle, the distance between the first bottom surface and the substrate is greater than the thickness of the coating layer.
6. The coating method of claim 4 , wherein the width of the first bottom surface is less than the width of the second bottom surface.
7. The coating method of claim 6 , wherein a distance between the first bottom surface and the substrate is greater than a distance between the second bottom surface and the substrate.