Organic light emitting display and method of fabricating the same
An organic light emitting display (OLED) and method of fabricating the same are provided having a reduced number of photolithography and etching steps. The method includes a source electrode and a drain electrode being formed over a substrate, and at least one insulating layer being formed over the source electrode and drain electrode. After the insulation layer is formed, a reflecting layer pattern is formed. A via contact hole is formed through the insulating layer using the reflecting layer pattern as an etching mask. Multiple insulating layers may be formed and have a via contact hole etched therethrough in one etching step using the reflecting layer pattern as a mask. Alternatively, each insulating layer may have a via contact hole separately etched therethrough, with the last layer being etched using the reflective layer pattern as a mask. Consequently, the number of photolithography and etching steps is reduced thereby leading to higher manufacturing yield and lower manufacturing cost.
1 . An organic light emitting display (OLED), comprising:
a passivation layer including a first via contact hole formed therethrough, wherein the passivation layer is arranged above a substrate on which a thin film transistor having a gate electrode, a source electrode and a drain electrode are formed, wherein the first via contact hole exposes either one of the source electrode or the drain electrode;
a stacked structure comprising a planarization layer pattern and a reflecting layer pattern formed above the passivation layer, wherein the planarization layer pattern and the reflecting layer include a second via contact hole therethrough exposing the first via contact hole, and share an etching surface in a thin film transistor region;
a pixel electrode formed on the reflecting layer pattern and contacting either the source electrode or the drain electrode through the second via contact hole; and
an insulating layer pattern formed above portions of the passivation layer and the pixel electrode and exposing a pixel region while filling at least a portion of the second via contact hole.
2 . The OLED of claim 1 , wherein the planarization layer pattern is made of a material selected from a group of materials consisting of polyimide, benzocyclobutene-based resin, spin on glass (SOG), and acrylate.
3 . The OLED of claim 1 , wherein the reflecting layer pattern comprises a metal selected from a group of metals consisting of aluminum, silver, or an alloy of silver and aluminum.
4 . An organic light emitting display (OLED), comprising:
a stacked structure including a first insulating layer pattern and a reflecting layer pattern formed above a substrate, a thin film transistor including a gate electrode, a source electrode, and a drain electrode formed on the substrate, wherein the first insulating layer pattern and the reflecting layer pattern comprise a via contact hole therethrough which exposes either the source electrode or the drain electrode and share an etching surface in a thin film transistor region;
a pixel electrode formed on the reflecting layer pattern and contacting either the source electrode or the drain electrode through the via contact hole; and
a second insulating layer pattern formed above predetermined portions of the thin film transistor and the pixel electrode and exposing a portion of the pixel electrode to define a pixel region and filling at least a portion of the via contact hole.
5 . The OLED of claim 4 , wherein the first insulating layer pattern comprises a material selected from a group of materials consisting of polyimide, benzocyclobutene-based resin, spin on glass (SOG), and acrylate.
6 . The OLED of claim 4 , wherein the first insulating layer pattern comprises a stacked structure including a planarization layer and a passivation layer.
7 . The OLED of claim 6 , wherein the passivation layer comprises any one of a silicon nitride layer, a silicon oxide layer, and a stack of a silicon nitride layer and a silicon oxide layer.
8 . The OLED of claim 4 , wherein the reflecting layer pattern comprises a metal selected from a group of metals consisting of aluminum, silver, or an alloy of silver and aluminum.
9 . A method of fabricating an organic light emitting display (OLED), comprising:
forming a buffer layer having a predetermined thickness on a substrate, and forming a thin film transistor including a gate electrode, a source electrode and a drain electrode;
forming a passivation layer above the buffer layer;
etching the passivation layer to form a first via contact hole which exposes either the source electrode or the drain electrode;
forming a planarization layer on predetermined portions of the passivation layer and forming a reflecting layer on predetermined portions of the planarization layer;
etching the reflecting layer to form a reflecting layer pattern;
etching the planarization layer using the reflecting layer pattern as an etching mask to form a second via contact hole which exposes the first via contact hole;
forming a pixel electrode contacting either the source electrode or the drain electrode through the first via contact hole and the second via contact hole; and
forming an insulating layer pattern on a predetermined portion of the pixel electrode to define a pixel region on the OLED.
10 . The method of claim 9 , wherein the planarization layer comprises a material selected from a group of materials consisting of polyimide, benzocyclobutene-based resin, spin on glass (SOG), and acrylate.
11 . The method of claim 9 , wherein the reflecting layer pattern comprises a metal selected from a group of metals consisting of aluminum, silver, or an alloy of silver and aluminum.
12 . The method of claim 9 , wherein the reflecting layer is etched by either a wet-etching method or a dry-etching method.
13 . The method of claim 9 , wherein the planarization layer is etched by a dry-etching method using oxygen plasma.
14 . The method of claim 9 , wherein the planarization layer is etched by a dry-etching method using a plasma with either one of a CF 4 or a SF 6 gas and comprising at least oxygen and fluorine when the planarization layer comprises silicon.
15 . A method of fabricating an organic light emitting display (OLED), comprising:
forming a buffer layer including a predetermined thickness on a substrate, and forming a thin film transistor including a gate electrode, a source electrode and a drain electrode on the buffer layer;
forming a first insulating layer over the buffer layer and forming a reflecting layer over the first insulating layer;
etching the reflecting layer to form a reflecting layer pattern;
etching the first insulating layer using the reflecting layer pattern as an etching mask to form a via contact hole therethrough which exposes either one of the source electrode or the drain electrode;
forming a pixel electrode coupled to either one of the source electrode or the drain electrode through the via contact hole; and
forming a second insulating layer pattern to define a pixel region on the OLED.
16 . The method of claim 15 , wherein the first insulating layer is made of a material selected from a group of materials consisting of polyimide, benzocyclobutene-based resin, spin on glass (SOG), and acrylate.
17 . The method of claim 15 , wherein the first insulating layer comprises a passivation layer under a planarization layer.
18 . The method of claim 17 , wherein the passivation layer is formed of one of either a silicon nitride layer, a silicon oxide layer, or a stack of a silicon nitride layer and a silicon oxide layer.
19 . The method of claim 15 , wherein the reflecting layer pattern comprises a metal selected from a group of metals consisting of aluminum, silver, or an alloy of aluminum and silver.
20 . The method of claim 15 , wherein the reflecting layer is etched by either a wet-etching method or a dry-etching method.
21 . The method of claim 15 , wherein the planarization layer is etched by a dry-etching method using oxygen plasma.
22 . The method of claim 15 , wherein the planarization layer is etched by a dry-etching method using a plasma with either one of a CF 4 or SF 6 gas containing at least oxygen and fluorine when the planarization layer contains silicon.