Method of fabricating light extraction substrate for OLED
View Patent ↗An organic light-emitting device (OLED) which can improve the light extraction efficiency of the OLED, a method of fabricating the same and an OLED including the same. The light extraction substrate is disposed on one surface of an OLED through which light generated from the OLED is emitted outward, and includes a base substrate and a light extraction layer formed on the base substrate. The light extraction layer has therein a plurality of pores which is formed on the base substrate such that the base substrate forms a bottom surface of the plurality of pores.
1. A method of fabricating a light extraction substrate which is disposed on one surface of an organic light-emitting device through which light generated from the organic light-emitting device is emitted outward, the method comprising:
forming a frit powder by melting and pulverizing a glass;
forming a frit paste by mixing the formed frit powder into an organic solvent to which an organic binder is added;
applying the formed frit paste on a base substrate by screen printing, thereby printing a plurality of bead structures on the base substrate; and
firing the printed frit paste to form a light extraction layer in which a plurality of pores is formed, each pore having the base substrate as a bottom surface of the pore and extending into a respective bead of a plurality of beads, each bead formed from and corresponding to a respective bead structure of the printed bead structures.
2. The method according to claim 1 , wherein forming the frit powder comprises melting and pulverizing the glass having a softening point ranging from 350 to 600° C.
3. The method according to claim 1 , wherein forming the frit powder comprises controlling the process of pulverizing the glass such that a maximum particle size of the glass is 15 μm or less.
4. The method according to claim 1 , wherein forming the frit paste comprises controlling a content of the frit powder to be in a range from 50 to 80% of the organic solvent.
5. The method according to claim 4 , wherein forming the frit paste comprises controlling a viscosity of the frit paste to be in a range from 30,000 to 150,000 cps.
6. The method according to claim 1 , further comprising forming a planarization layer on the light extraction layer.
7. The method according to claim 1 , wherein applying the formed frit paste and firing the printed frit paste forms the beads in form of a plurality of hemispherical beads formed on the base substrate.
8. The method according to claim 7 , wherein the plurality of beads is formed continuously or discontinuously on the base substrate.