Manufacturing method for reflector, reflector, and liquid crystal display
View Patent ↗A flat organic insulating layer is formed on a substrate provided with thin film transistors by coating and baking. Next, a pulse-shaped laser beam is irradiated on the organic insulating layer and a contact hole and an undulation are formed in and on the organic insulating layer by ablation. The undulation is formed in such a way as to have four or more height levels.
1. A manufacturing method for making a reflector, comprising the steps of:
forming an insulating layer using an organic material having an absorption band in a predetermined wavelength range;
forming protrusions on the insulating layer by ablation by irradiating a laser beam of a predetermined range of wavelengths on the insulating layer to break chemical bonds in the organic material and evaporate the surface of the insulating layer; and
forming an electrode on the insulating layer.
2. The method of claim 1 , wherein the laser beam is irradiated through a mask that has plural different transmittance levels for the laser beam and the ablation forms in the insulating layer plural valleys separated by peaks, the peaks having at least four different heights.
3. The manufacturing method according to claim 1 , wherein scanning irradiation is performed with said laser beam which has a spot shape.
4. The manufacturing method according to claim 1 , wherein in said ablation step, said laser beam is irradiated with a pulse shape.
5. The manufacturing method according to claim 1 , further comprising the steps of forming a switching element under said insulating layer, and
forming a contact hole through a bottom of which one end of said switching element is exposed.
6. The manufacturing method according to claim 1 , further comprising the steps of forming a flat portion on said insulating layer, and
forming a transparent electrode on said flat portion.
7. The manufacturing method according to claim 1 , further comprising a step of annealing said insulating layer after said irradiating step.
8. The method of claim 2 , wherein the valleys have at least four different heights that are different from the heights of the peaks.
9. The manufacturing method according to claim 2 , wherein said laser beam incident to said mask has a flat profile.