KR102202795B1 - Organic light emitting device - Google Patents

Abstract

The present invention relates to an organic light-emitting display device capable of realizing high resolution by securing a high-capacity capacitance in a limited area and preventing defects in bright spots, comprising: a plurality of pixel regions and at least two thin film transistors disposed in each pixel region And first and second storage electrodes, and an organic light emitting diode. The first insulating layer covers the thin film transistors and includes a plurality of first holes exposing portions of each thin film transistor. The first storage electrode is disposed on the first insulating layer so as to overlap at least one of the at least two thin film transistors. The second storage electrode is disposed to overlap the first storage electrode with a second insulating layer disposed therebetween to cover the first storage electrode. The first electrode of the organic light emitting diode is disposed to overlap the second storage electrode with the third insulating layer therebetween. The second electrode is disposed to overlap the first electrode with the organic emission layer therebetween. At least one of the first and second storage electrodes disposed to overlap each other at a position overlapping the plurality of first holes has a through hole that is removed corresponding to the position of the first hole.

Description

Organic light emitting display device{ORGANIC LIGHT EMITTING DEVICE}

The present invention relates to an organic light-emitting display device, and more particularly, to an organic light-emitting display device capable of realizing high resolution by securing a high capacitance in a limited area and preventing defects in bright spots.

Recently, various flat panel display devices capable of reducing the weight and volume, which are the disadvantages of a cathode ray tube (CRT), have been developed. Examples of such a flat panel display include a liquid crystal display (LCD), a field emission display (FED), a plasma display panel (PDP), and an organic light emitting display (OLED). Organic Light Emitting Display). Among these flat panel displays, the Organic Light Emitting Display is a self-luminous display device that excites an organic compound to emit light, and does not require a backlight used in LCD, so it is possible to not only be light-weight and thin, but also There is an advantage that can be simplified. In addition, organic light-emitting display devices are widely used in that they can be manufactured at a low temperature, have a response speed of less than 1 ms, and have high-speed response speed, as well as low power consumption, wide viewing angle, and high contrast. .

The organic light emitting diode display includes an organic light emitting diode that converts electrical energy into light energy. The organic light emitting diode includes an anode electrode, a cathode electrode, and an organic light emitting layer disposed between the electrodes. Holes are injected from the anode electrode and electrons are injected from the cathode electrode. When the holes injected through the anode electrode and the cathode electrode are injected into the organic emission layer (EML), respectively, excitons, excitons, are formed, and the excitons emit light while emitting energy as light.

The organic light emitting display device includes a plurality of pixels partitioned by intersections of gate lines, data lines, and common power lines. Each pixel includes a switching thin film transistor, a driving thin film transistor, a storage capacitor, and an organic light emitting diode. The switching thin film transistor is turned on when a scan pulse is supplied to the gate line and supplies a data signal supplied to the data line to the storage capacitor and the gate electrode of the driving thin film transistor. The driving thin film transistor controls the amount of light emitted from the organic light emitting diode by controlling a current supplied from the power line to the organic light emitting diode in response to a data signal supplied to the gate electrode. Even when the switching thin film transistor is turned off, the storage capacitor is supplied from the data line through the switching thin film transistor so that the driving thin film transistor supplies a constant current until the data signal of the next frame is supplied to maintain the light emission of the organic light emitting diode (OLED). Charges the supplied data voltage.

Hereinafter, a conventional organic light emitting display device will be described with reference to FIG. 1. 1 is a cross-sectional view illustrating a conventional organic light emitting display device.

Referring to FIG. 1, a buffer layer 110 is positioned on a substrate 100, an active layer 115a and a capacitor lower electrode 115b are positioned on the buffer layer 110, and a gate insulating layer 120 insulating them is formed. Located. The gate electrode 130a and the capacitor upper electrode 130b are positioned on the gate insulating layer 120 and an interlayer insulating layer 135 is positioned to insulate them. The source electrode 145a and the drain electrode 145b connected to the active layer 115a through contact holes 140a and 140b are positioned on the interlayer insulating layer 135 to form a thin film transistor.

The passivation layer 150 is positioned on the interlayer insulating layer 135 to cover the source electrode 145a and the drain electrode 145b of the thin film transistor, and a via hole 155 penetrating the passivation layer 150 is formed on the passivation layer 150. A first electrode 160 (eg, a cathode electrode) connected to the drain electrode 145b of the thin film transistor is positioned. A bank layer 165 including an opening 170 exposing the first electrode 160 is positioned in the passivation layer 150 on which the first electrode 160 is disposed, and the organic light emitting layer 175 is on the first electrode 160. ) Is located. In addition, a spacer 180 partitioning the organic emission layer 175 is positioned on the bank layer 165, and the second electrode 185 covering the organic emission layer 175 and the bank layer 180 is positioned to display organic light emission. The device is configured.

However, as the display device has recently increased in size and high resolution is required, the pixel size tends to become smaller. In this configuration, when the pixel size decreases, the thin film transistors and the aforementioned lines are integrated and arranged very closely. Accordingly, in the conventional high-resolution organic light emitting display device, the area of the storage capacitor, that is, the overlapping area of the capacitor lower electrode 115b and the capacitor upper electrode 130b is reduced, resulting in insufficient capacitance.

An object of the present invention is to solve the above-described problems, and to provide an organic light-emitting display device capable of maintaining the capacitance of a capacitor even in a high-resolution organic light-emitting display device.

The organic light emitting display device of the present invention for achieving the above object includes at least two thin film transistors, first and second storage electrodes, and an organic light emitting diode disposed on a substrate. The first insulating layer has a plurality of holes exposing portions of each thin film transistor. The first storage electrode is disposed on the first insulating layer so as to overlap at least one of the at least two thin film transistors. The second storage electrode is disposed to overlap the first storage electrode with a second insulating layer disposed therebetween to cover the first storage electrode. The second insulating layer corresponds to the second passivation layer PAS2 described in the embodiment. The first electrode of the organic light emitting diode is disposed to overlap the second storage electrode with the third insulating layer therebetween. The third insulating film corresponds to the planarization film described in the embodiment. The second electrode is disposed to overlap the first electrode with the organic emission layer therebetween. At least one of the first and second storage electrodes has a through hole corresponding to a position of at least one of the plurality of holes. The plurality of holes correspond to the first to fourth contact holes described in the embodiment.

In the above configuration, the first insulating layer is a gate insulating layer covering the active layer of each thin film transistor, an interlayer insulating layer covering the gate electrode of each thin film transistor disposed on the gate insulating layer, and each of the each disposed on the interlayer insulating layer. It may include at least one of a first passivation layer covering the source electrode and the drain electrode of the thin film transistor.

Also, at least two thin film transistors may include one driving thin film transistor. The gate electrode of the driving thin film transistor is connected to the second storage electrode of the first storage capacitor through a first connection pattern, and the driving drain electrode of the driving thin film transistor is connected to the first storage capacitor through a second connection pattern. It may be connected to the storage electrode and the first electrode.

In addition, the first storage electrode is connected to the second connection pattern connected to the driving drain electrode exposed through a first contact hole penetrating the first and second insulating layers, and the second connection pattern penetrates the third insulating layer. It may be connected to the first electrode through the contact hole. Here, the first contact hole corresponds to the sixth contact hole described in the embodiment.

Further, the second storage electrode may be connected to the first connection pattern through a second contact hole penetrating the first and second insulating layers. Here, the second contact hole corresponds to the fifth contact hole described in the embodiment.

Also, the at least two thin film transistors may further include one switching thin film transistor. The switching drain electrode of the switching thin film transistor may be connected to the driving drain electrode of the driving thin film transistor.

According to the organic light emitting diode display according to the present invention, the storage electrodes are positioned above the thin film transistors, so even if the pixel area is reduced according to the trend of high resolution, the capacity of the storage capacitor can be secured even if the size of each pixel area is reduced. Can be obtained.

In addition, a through hole may be formed by removing at least one of the two storage electrodes constituting the storage capacitor at a portion overlapping with the lower contact holes, thereby preventing the two storage electrodes from being shorted. Accordingly, it is possible to obtain an effect of preventing generation of bright spots in the organic light emitting display device that may occur due to a short between the storage electrodes.

1 is a cross-sectional view showing a conventional organic light emitting display device;
2 is a plan view showing one pixel of an organic light emitting display device according to an exemplary embodiment of the present invention;
3 is a plan view showing an example of storage capacitors of an organic light emitting diode display according to a first embodiment of the present invention;
4 is a cross-sectional view illustrating a partial area of the organic light emitting diode display shown in FIGS. 2 and 3;
5 is a tomography photograph taken of an area R1 shown in FIG. 4;
6 is a plan view illustrating another example of storage electrodes of the organic light emitting display device illustrated in FIG. 2;
7 is a cross-sectional view illustrating a partial area of the organic light emitting display device illustrated in FIGS. 2 and 6;
FIG. 8 is a plan view illustrating still another example of storage electrodes of the organic light emitting display device illustrated in FIG. 2;
9 is a cross-sectional view illustrating a partial area of the organic light emitting diode display shown in FIGS. 2 and 8.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals throughout the specification mean substantially the same constituent elements. In the following description, when it is determined that a detailed description of known content or configuration related to the present invention may unnecessarily obscure the subject matter of the present invention, a detailed description thereof will be omitted.

First, an organic light emitting display device according to an exemplary embodiment of the present invention will be described with reference to FIG. 2. 2 is an example of a circuit diagram showing one pixel of an organic light emitting display device according to an embodiment of the present invention.

Referring to FIG. 2, one pixel of the organic light emitting diode display according to an exemplary embodiment of the present invention is a gate line (GL#n, GL#(n-1)), a data line (DL), an initialization line (Vini), and And a cell driver DU connected to the /off control line EM#n and the power line VDD, and an organic light emitting diode OLED connected between the cell driver DU and a ground (ground).

The cell driver DU includes three switching thin film transistors T1, T2, and T3, one driving thin film transistor Td, and two storage capacitors Cdt and Cst.

The first switching thin film transistor T1 has a first gate electrode connected to the on/off control line EM#n, a first source electrode connected to the power line VDD, and driving the driving thin film transistor Td. The first drain electrode is connected to the drain electrode. The first switching thin film transistor T1 serves to control the emission period of each pixel.

The second switching thin film transistor T2 has a second gate electrode connected to the n-th gate line GL#n, a second source electrode connected to the data line DL, and a driving gate of the driving thin film transistor Td. The second drain electrode is connected to the electrode. The second switching thin film transistor T2 serves to control the data signal supplied through the data line DL to be stored in the first storage capacitor Cst.

The third switching thin film transistor T3 has a third gate electrode connected to the n-1th gate line GL#(n-1), a third source electrode connected to the initialization line Vini, and a driving thin film transistor The third drain electrode is connected to the driving drain electrode of Td, the first storage electrode of the first storage capacitor Cst, and the third storage electrode of the second storage capacitor Cdt. The third switching thin film transistor T3 may be supplied with an initialization voltage to a node to which the driving drain electrode, the first storage electrode of the first storage capacitor Cst, and the third storage electrode of the second storage capacitor Cdt are connected. It plays a role of controlling so that there is.

The driving thin film transistor Td has a gate electrode connected to the second drain electrode of the second switching thin film transistor T2 and the second storage electrode of the first storage capacitor Cst, and the first switching thin film transistor T1 1 The driving drain electrode is connected to the drain electrode, and the anode electrode of the organic light emitting diode OLED, the third drain electrode of the third switching thin film transistor T3, the first storage electrode of the first storage capacitor Cst, and the second The driving drain electrode is connected to the third storage electrode of the storage capacitor Cdt. The driving thin film transistor Td serves to supply a driving current to the organic light emitting diode OLED based on the data voltage stored in the first storage capacitor Cst.

The first storage capacitor Cst has a second storage electrode connected to the driving gate electrode of the driving thin film transistor Td, a driving drain electrode of the driving thin film transistor Td, and a third drain of the third switching thin film transistor T3. The first storage electrode is connected to the electrode and the third storage electrode of the second storage capacitor Cdt. The first storage capacitor Cst serves to store a data voltage.

The second storage capacitor Cdt has a fourth storage electrode connected to the power line VDD, a driving drain electrode of the driving thin film transistor Td, a third drain electrode of the third switching thin film transistor T3, and a first storage capacitor. The third storage electrode is connected to the first storage electrode of the capacitor Cst. The second storage capacitor Cdt serves to store the compensation voltage (or boosting voltage).

In the organic light emitting diode OLED, a first electrode (eg, an anode electrode) is connected to a drain electrode of the driving thin film transistor Td, and a second electrode (cathode electrode) is connected to the ground. The organic light emitting diode OLED serves to emit light in response to a driving current supplied from the driving thin film transistor Td.

According to this configuration, when the gate signal supplied through the n-1th gate line GL#(n-1) becomes logic high, the third switching thin film transistor T3 is turned on and initialization is performed. When the third switching thin film transistor T3 is turned on, the driving drain electrode of the driving thin film transistor Td, the first storage electrode of the first storage capacitor Cst, and the third storage electrode of the second storage capacitor Cdt are connected. An initialization voltage is supplied to the first node n1. In this case, the n-1th gate signal may maintain a logic high state until the sampling step starts, but is not limited thereto. Further, the light emission control signal supplied through the emission control line EM#n may be in a logic low state, while the gate signal supplied through the nth data line GL#n may be in a logic high state.

When initialization is in progress, the first node n1 to which the driving drain electrode of the driving thin film transistor Td, the first storage electrode of the first storage capacitor Cst, and the third storage electrode of the second storage capacitor Cdt are connected. Is initialized to a specific voltage (eg, a voltage close to the ground level or a negative voltage).

Next, when the light emission control signal supplied through the light emission control line Em#n becomes logic high, and the gate signal supplied through the nth gate line GL#n becomes logic high, the first and second switching The thin film transistors T1 and T2 are turned on and sampling is performed. When the first and second switching thin film transistors T1 and T2 are turned on, the data signal can be compensated through sampling to compensate for the threshold voltage Vth of the driving thin film transistor Td. In this case, the gate signal supplied through the (n-1)th gate line GL#(n-1) may maintain a logic low state.

When the gate signal supplied through the light emission control line Em#n becomes logic low while the gate signal supplied through the n-th gate line GL#n remains logic high, the first switching thin film transistor T1 Turns off and data begins to be written. When data writing is performed, the data voltage compensated for the threshold voltage Vth of the driving thin film transistor Td is stored in the first storage capacitor Cst. In this case, the signals supplied to the emission control line Em#n and the n-1th gate line GL#(n-1) may maintain a logic low state.

When data writing is completed and the signal supplied to the light emission control line Em#n is converted from logic low to logic high, the driving thin film transistor Td is turned on. Further, the driving thin film transistor Td generates a driving current in response to the data voltage stored in the first storage capacitor Cst, and the organic light emitting diode OLED emits light in response to the driving current.

Next, a configuration of an organic light-emitting display device according to a first embodiment of the present invention will be described with reference to FIGS. 3 and 4. 3 is a plan view illustrating an example of storage capacitors of the organic light emitting display device according to the first embodiment of the present invention, and FIG. 4 is a cross-sectional view illustrating a partial area of the organic light emitting display device illustrated in FIGS. 2 and 3. .

In FIGS. 3 and 4, elements shown in FIG. 2 are omitted for clarity of technical features of the present invention, prevention of redundant description, and simplification of the drawings. In particular, FIG. 3 shows a portion related to a storage capacitor, and FIG. 4 shows a driving thin film transistor Td, a third switching thin film transistor T3, and a first storage capacitor Cst. . In addition, in the description related to each drawing, names such as first, second, and third do not necessarily indicate an order, and it is necessary to understand that they are names given in relation to each component shown in FIG. 2.

3 and 4, a semiconductor active layer including a driving active layer Ad and a third active layer A3 spaced apart from each other in the same layer is disposed on a substrate SUB. The driving active layer Ad and the third active layer A3 are semiconductor active layers formed by implanting impurity ions into amorphous silicon (a-Si). The driving active layer Ad includes a driving active region AAd and a driving drain region DAd. The third active layer A3 includes a third source region SA3 and a third drain region DA3 disposed with the third active region AA3 interposed therebetween.

An inorganic insulating film such as silicon nitride (SiNx) or silicon oxide (SiOx), or a buffer insulating film formed of multiple layers thereof may be disposed between the substrate SUB and the semiconductor active layer.

A gate insulating film GI is disposed on the driving active layer Ad and the third active layer A3 to cover and insulate them. The gate insulating layer GI may be formed of an inorganic insulating layer such as silicon nitride (SiNx) or silicon oxide (SiOx), or multiple layers thereof. Gate lines GL#n and GL#(n-1), a driving gate electrode Gd, and a third gate electrode G3 are disposed on the gate insulating layer GI (Fig. 2 and See Fig. 4). The driving gate electrode Gd is disposed to extend from the n-1th gate line GL#(n-1) and overlap the driving active region AAd of the driving active layer Ad. The third gate electrode G3 is disposed to be spaced apart from the n-1th gate line GL#(n-1) and the driving gate electrode Gd. The emission control line EM#n, which is not illustrated in FIG. 4, and first and second gate electrodes of the first and second switching thin film transistors T1 and T2 are also disposed on the gate insulating layer GI.

The emission control line EM#n, the gate lines GL#n and GL#(n-1), the driving gate electrode Gd, and the first to third gate electrodes are aluminum (Al) and copper (Cu). , Molybdenum (Mo), chromium (Cr), titanium (Ti), gold (Au), silver (Ag), tungsten (W) or a single layer consisting of any one selected from the group consisting of alloys thereof or a multilayer thereof Can be made.

On the gate insulating layer GI on which the emission control line EM#n, the gate lines GL#n and GL#(n-1), the driving gate electrode Gd, and the first to third gate electrodes are disposed, An interlayer insulating layer ILD is positioned to insulate and cover. The interlayer insulating layer ILD may be formed of an inorganic insulating layer such as silicon nitride (SiNx) or silicon oxide (SiOx), or multiple layers thereof.

A data line DL crossing the gate lines GL#n and GL#(n-1) is disposed on the interlayer insulating layer ILD. Also on the interlayer insulating film ILD, the driving source electrode, the driving drain electrode Dd, and the first connection pattern CP1 of the driving thin film transistor Td, and the third source electrode S3 of the third switching thin film transistor T3. And a third drain electrode D3 is disposed. First and second source electrodes and first and second drain electrodes of the initialization line Vini, the power line VDD, and the first and second switching thin film transistors T1 and T2 not shown in FIG. 4 are also It is disposed on the interlayer insulating film ILD.

The initialization line Vini, the power line VDD, the first to third source electrodes and the first to third drain electrodes of the first to third switching thin film transistors T1 to T3, and the first connection pattern ( The source-drain electrode layer containing CP1) is aluminum (Al), copper (Cu), molybdenum (Mo), chromium (Cr), titanium (Ti), gold (Au), silver (Ag), tungsten (W), or these It may be made of a single layer made of any one selected from the group consisting of an alloy of or multiple layers thereof.

The driving drain electrode Dd of the driving thin film transistor Td is a driving drain region of the driving active layer Ad exposed through the interlayer insulating layer ILD and the first contact hole CH1 penetrating the gate insulating layer GI. GAd). The first connection pattern CP1 is disposed to contact the driving gate electrode Gd exposed through the second contact hole CH2 penetrating the interlayer insulating layer ILD. The third drain electrode D3 of the third switching thin film transistor T3 is formed of the third active layer A3 exposed through the third contact hole CH3 penetrating the interlayer insulating layer ILD and the gate insulating layer GI. The third active layer A3 is connected to the third drain region DA3, and the third source electrode S3 is exposed through the fourth contact hole CH3 penetrating the interlayer insulating layer ILD and the gate insulating layer GI. ) Is connected to the third source area SA3. The driving drain electrode Dd of the driving thin film transistor Td is connected to the third drain electrode D3 of the third switching thin film transistor T3. The first and second source electrodes and the first and second drain electrodes of the first and second switching thin film transistors T1 and T3 not shown in FIG. 4 are also first and second through contact holes exposing the semiconductor active layer. And the second source regions and the first and second drain regions, respectively. The connection relationship between each component is as shown in FIG. 2.

On the interlayer insulating film ILD on which the source-drain electrode layer is disposed, the first passivation film PAS1 is positioned to cover them. The first passivation layer PAS1 may be formed of an inorganic insulating layer such as silicon nitride (SiNx) or silicon oxide (SiOx).

The first storage electrode ST1 of the first storage capacitor Cst is disposed on the first passivation layer PAS1. The first storage electrode ST1 is disposed to overlap the driving thin film transistor Td.

A second passivation layer PAS2 is disposed on the first passivation PAS1 where the first storage electrode ST1 is located to cover the first storage electrode ST1. The second passivation layer PAS2 may be formed of an inorganic insulating layer such as silicon nitride (SiNx) or silicon oxide (SiOx).

The first and second passivation layers PAS1 and PAS2 include a fifth contact hole CH5 exposing a portion of the first connection pattern CP1 connected to the driving gate electrode Gd of the driving thin film transistor Td, And a sixth contact hole CH6 exposing a connection portion between the third drain electrode D3 of the third switching thin film transistor T3 and the source electrode Sd of the driving thin film transistor Td.

On the second passivation layer PAS2 in which the fifth and sixth contact holes CH5 and CH6 are formed, the first storage electrode ST1 of the first storage capacitor Cst and the second passivation layer PAS2 is interposed therebetween. The second storage electrode ST2 is positioned to face each other. A second connection connecting the third drain electrode D3 and the first storage electrode ST1 of the third switching thin film transistor T3 exposed through the sixth contact hole C6 on the second passivation layer PAS2. The pattern CP2 is located.

In the above description, the connection relationship between the third and fourth storage electrodes of the second storage capacitor Cdt shown in FIG. 2 and other components is the first storage capacitor Cst except for a specific object to which it is connected. Since the first and second storage electrodes ST1 and ST2 of are configured similarly to the connection relationship with other components, they are omitted to avoid complicating the description.

The first and second storage capacitors Cst and Cdt and the connection pattern CP are aluminum (Al), copper (Cu), molybdenum (Mo), chromium (Cr), titanium (Ti), gold (Au), It may be selected from the group consisting of silver (Ag), tungsten (W), or an alloy thereof.

A planarization layer PLN is positioned on the second passivation layer PAS2 on which the second storage electrode ST2 and the connection part CP are located to cover the second storage electrode ST2 and the connection part CP. The planarization layer PLN may be formed of an organic insulating layer such as polyacrylic or polyimide. The planarization layer PLN2 includes a seventh contact hole CH7 exposing a portion of the second storage electrode ST2.

On the planarization layer PLN in which the seventh contact hole CH9 is formed, the first electrode (for example, the anode electrode) of the organic light emitting diode is in contact with the second storage electrode ST2 exposed through the seventh contact hole CH7. (AND)) is located. The bank layer BK including an opening exposing the first electrode AND is positioned on the planarization layer PLN on which the first electrode AND is disposed, and the organic emission layer LE is positioned on the first electrode AND do. In addition, a spacer SSP for partitioning the organic emission layer LE is positioned on the bank layer BK, and a second electrode (for example, the cathode electrode CA) covers the organic emission layer LE and the bank layer BK. )) is positioned to form an organic light emitting diode (OLED in Fig. 1). The anode electrode (AND) and the cathode electrode are aluminum (Al), copper (Cu), molybdenum (Mo), chromium (Cr), titanium (Ti), gold (Au), silver (Ag), tungsten (W), or these It may be selected from the group consisting of an alloy of.

According to the storage capacitor of the organic light emitting diode display according to the exemplary embodiment described above, the first storage electrode ST1 and the second storage electrode ST2 (or the third storage electrode and the fourth storage electrode) are illustrated in FIG. 3 and As shown in FIG. 4, a storage capacitor is formed on the top of the thin film transistor. Accordingly, even if the size of each pixel area is reduced according to the trend of high resolution of the organic light emitting display device, an effect of securing the capacity of the storage capacitor can be obtained.

However, under the first and second storage electrodes ST1 and ST2, for example, a contact hole CH2 for connecting the driving gate electrode Gd of the driving thin film transistor Td and the first connection pattern CP1. ) Is formed, and the first and second storage electrodes ST1 and ST2 are disposed thereon, so that the first and second storage electrodes ST1 and ST2 are disposed in the region R1 corresponding to the contact hole CH2 as shown in FIG. 5. And the second storage electrodes ST1 and ST2 may be shorted to each other. FIG. 4 shows a short circuit between a first storage electrode ST1) and a second storage electrode ST2 of a first storage capacitor Cst in a region R1 at a location corresponding to the second contact hole CH2 in an exemplary embodiment of the present invention. This is a tomographic photograph showing the state of being. This short state may also occur in the third and fourth storage electrodes ST3 and ST4 of the second storage capacitor Sdt illustrated in FIG. 2.

In this way, when a short occurs between the first and second storage electrodes ST1 and ST2 or the third and fourth storage electrodes ST3 and ST4, a signal supplied from the power line VDD is transmitted to the organic light emitting diode. OLED) has a problem that can be displayed as a bright spot.

Hereinafter, an organic light-emitting display device according to the second and third embodiments of the present invention capable of solving the above-described problems will be described with reference to FIGS. 6 to 9.

First, an organic light-emitting display device according to a second exemplary embodiment of the present invention will be described with reference to FIGS. 6 and 7. 6 is a plan view illustrating another example of storage electrodes of the organic light emitting display device illustrated in FIG. 2, and FIG. 7 is a cross-sectional view illustrating a partial region of the organic light emitting display device illustrated in FIGS. 2 and 6.

6 and 7, the organic light emitting diode display according to the second exemplary embodiment of the present invention is illustrated in FIGS. 3 and 4 except that the first storage electrode has a first through hole VH1. It is substantially the same as the previous embodiment. Accordingly, only portions different from those shown in FIGS. 3 and 4 will be described in order to avoid redundant description.

6 and 7, the first storage electrode ST1 of the first storage capacitor Cst is positioned at a position corresponding to the second contact hole CH2 exposing the driving gate electrode Gd. And a first through hole TH1 from which a portion of the storage electrode ST1 has been removed. The first passivation layer PAS1 is exposed through the first through hole TH1. The third storage electrode ST3 of the second storage capacitor Cdt is, for example, at a position corresponding to the contact hole CH exposing a portion of the third drain electrode D3 of the third switching transistor ST3. And a second through hole TH2 from which a portion of the third storage electrode ST3 has been removed.

The first and second through-holes TH1 and TH2 are under the first and second storage electrodes ST1 and ST2 to prevent a short circuit between the third and fourth storage electrodes ST3 and ST4. It may be formed larger than the positioned contact holes CH2 and CH.

Therefore, since the first storage electrode ST1 and the third storage electrode ST3 are removed at a position overlapping the lower contact holes CH2 and CH, the through holes TH1 and TH2 are formed. The first and second storage electrodes ST1 and ST2 and the third and fourth storage electrodes ST3 and ST4 are not short-circuited. Accordingly, it is possible to obtain an effect of preventing generation of bright spots in the display device.

Next, an organic light-emitting display device according to a third exemplary embodiment of the present invention will be described with reference to FIGS. 8 and 9. FIG. 8 is a plan view illustrating another example of storage electrodes of the organic light emitting display device illustrated in FIG. 2, and FIG. 9 is a cross-sectional view illustrating a partial region of the organic light emitting display device illustrated in FIGS. 2 and 8.

8 and 9, the organic light emitting diode display according to the third exemplary embodiment of the present invention is illustrated in FIGS. 3 and 4 except that the first storage electrode includes a third through hole VH3. It is substantially the same as the previous embodiment. Accordingly, only portions different from those shown in FIGS. 3 and 4 will be described in order to avoid redundant description.

As shown in FIGS. 8 and 9, the second storage electrode ST2 of the first storage capacitor Cst is positioned at a position corresponding to the second contact hole CH2 exposing the driving gate electrode Gd. A third through hole TH3 from which a portion of the storage electrode ST1 has been removed is included. The second passivation layer PAS2 is exposed through the third through hole TH3. The third storage electrode ST3 of the second storage capacitor Cdt is, for example, at a position corresponding to the contact hole CH exposing a portion of the third drain electrode D3 of the third switching transistor ST3. And a fourth through hole TH4 from which a portion of the third storage electrode ST3 has been removed.

The third and fourth through-holes TH3 and TH4 are under the first and second storage electrodes ST1 and ST2 to prevent a short circuit between the third and fourth storage electrodes ST3 and ST4. It may be formed larger than the positioned contact holes CH2 and CH.

According to the organic light emitting display device according to the third embodiment of the present invention described above, the first storage electrode ST1 and the third storage electrode ST3 are disposed at a position overlapping the lower contact holes CH2 and CH. Since the through holes TH3 and TH4 are removed and formed, the first and second storage electrodes ST1 and ST2 and the third and fourth storage electrodes ST3 and ST4 are not short-circuited. Accordingly, it is possible to obtain an effect of preventing generation of bright spots in the display device.

In addition, unlike the second and third embodiments, the first to fourth storage electrodes are removed by removing all portions of the first to fourth storage electrodes at a position overlapping the lower contact holes CH2 and CH. A through hole may be formed in each of them, and even in this case, the first and second storage electrodes ST1 and ST2 and the third and fourth storage electrodes ST3 and ST4 may not be shorted. Therefore, when at least one of the portions of the first to fourth storage electrodes is removed at a position where the contact holes CH2 and CH are overlapped below, a through hole is formed in at least one of the first to fourth storage electrodes. It is possible to achieve the configuration of the object of the present invention.

It will be appreciated by those skilled in the art through the above description that various changes and modifications can be made without departing from the spirit of the present invention.

For example, in the embodiment of the present invention, it has been described as an example that the cell driver of the organic light emitting display device includes three switching thin film transistors, one driving thin film transistor, and two storage capacitors, but the present invention is limited thereto. no. For example, the cell driver of the organic light emitting display device of the present invention may be applied to a case including one driving thin film transistor, one switching thin film transistor, and one storage capacitor. In this case, the initialization line and the emission control line may be omitted. That is, the number of switching thin film transistors, driving thin film transistors, and storage capacitors constituting the cell driver is merely exemplary regardless of the essential features of the present invention, and thus should not be interpreted as limiting the present invention.

Accordingly, the present invention should not be limited to the content described in the detailed description, but should be defined by the claims.

T1, T2, T3: switching thin film transistor Td: driving thin film transistor
EM#n: Light emission control line Vini: Initialization line
VDD: power line GL#n, GL#: gate line
DL: data line GI: gate insulating film
ILD: interlayer insulating film PAS1, PAS2: passivation film
PLN: planarization film CP1, CP2: connection pattern
TH1, TH2, TH3, TH4: through hole

Claims (6)

At least two thin film transistors disposed on the substrate;
A first insulating layer having a plurality of holes exposing portions of each thin film transistor;
A first storage electrode disposed on the first insulating layer so as to overlap at least one of the at least two thin film transistors;
A second storage electrode disposed to overlap the first storage electrode with a second insulating layer disposed therebetween to cover the first storage electrode;
A first electrode disposed to overlap with the second storage electrode and a third insulating layer therebetween; And
And a second electrode disposed to overlap the first electrode with an organic emission layer therebetween,
Of the plurality of holes, at least one of the first and second storage electrodes disposed to overlap each other at a position of a hole overlapping with the first and second storage electrodes includes a through hole that is removed corresponding to the position of the overlapping hole. An organic light-emitting display device comprising: a.
The method of claim 1,
The first insulating layer includes a gate insulating layer covering the active layer of each thin film transistor, an interlayer insulating layer covering the gate electrode of each thin film transistor disposed on the gate insulating layer, and each of the thin film transistors disposed on the interlayer insulating layer An organic light-emitting display device comprising: a first passivation layer covering the source electrode and the drain electrode of.
The method of claim 1,
The at least two thin film transistors include one driving thin film transistor,
The gate electrode of the driving thin film transistor is connected to the second storage electrode of the first storage capacitor through a first connection pattern, and the driving drain electrode of the driving thin film transistor is connected to the first storage capacitor of the first storage capacitor through a second connection pattern. An organic light-emitting display device comprising: one storage electrode and connected to the first electrode.
The method of claim 3,
The first storage electrode is connected to the second connection pattern connected to the driving drain electrode exposed through a first contact hole penetrating the first and second insulating layers, and the second connection pattern includes a third insulating layer. An organic light-emitting display device comprising: connected to the first electrode through a contact hole penetrating therethrough.
The method of claim 4,
The second storage electrode is connected to the first connection pattern through a second contact hole penetrating the first and second insulating layers.
The method of claim 5,
The at least two thin film transistors further include one switching thin film transistor,
A switching drain electrode of the switching thin film transistor is connected to a driving drain electrode of the driving thin film transistor.

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