KR102609087B1 - Organic light emitting diode display device - Google Patents

Abstract

The present invention relates to an organic light emitting device, and particularly to an organic light emitting device including a top-gate type thin film transistor with a reduced mask process.
The present invention requires only four mask processes to form a top-gate type thin film transistor, so that an organic light emitting device can be formed with only a total of eight mask processes, including four mask processes for forming color filters and banks. there is.
Through this, compared to the existing organic light emitting device manufacturing process that required 12 mask processes, 4 mask processes can be eliminated, reducing process costs and shortening process time, improving productivity and productivity. The efficiency of the process can be improved.

Description

Organic light emitting diode display device}

The present invention relates to an organic light emitting device, and particularly to an organic light emitting device including a top-gate type thin film transistor with a reduced mask process.

In recent years, as society has entered a full-fledged information age, the display field, which processes and displays large amounts of information, has developed rapidly, and in response to this, various flat panel display devices have been developed and are in the spotlight.

Specific examples of such flat panel displays include Liquid Crystal Display device (LCD), Plasma Display Panel device (PDP), Field Emission Display device (FED), and electroluminescent display device. (Electroluminescence Display device: ELD), organic light emitting diodes (OLED), etc. These flat panel displays show excellent performance in terms of thinness, weight, and low power consumption, compared to the existing cathode ray tube (CRT). ) is rapidly replacing.

Among the above flat panel displays, organic light emitting devices are self-luminous devices and do not require backlights used in liquid crystal displays, which are non-light emitting devices, so they can be lightweight and thin.

In addition, it has an excellent viewing angle and contrast ratio compared to liquid crystal displays, is advantageous in terms of power consumption, can be driven at low direct current voltage, has a fast response speed, is strong against external shocks because the internal components are solid, and has a wide operating temperature range. It has advantages.

In particular, because the manufacturing process is simple, it has the advantage of significantly reducing production costs compared to existing liquid crystal displays.

1 is a circuit diagram of one pixel of a general organic light emitting device.

As shown, a gate wiring (GL) is formed in a first direction in one pixel area (P) of the organic light emitting device, and is disposed in a second direction crossing the first direction to define the pixel area (P). A data line (DL) is formed in each pixel area (P), and a switching thin film transistor (Tsw), a driving thin film transistor (Tdr), a storage capacitor (Cst), and a light emitting diode (E) are formed in each pixel area (P).

A switching thin film transistor (Tsw) is formed at the intersection of the data wire (DL) and the gate wire (GL), and inside each pixel area (P), a driving thin film transistor (Tdr) is electrically connected to the switching thin film transistor (Tsw). ) is formed.

At this time, the driving thin film transistor (Tdr) and the storage capacitor (Cst) are connected between the switching thin film transistor (Tsw) and the high potential voltage (VDD), and the light emitting diode (E) is connected between the driving thin film transistor (Tdr) and the low potential voltage (VDD). VSS).

Therefore, when a signal is applied through the gate wire (GL), the switching thin film transistor (STr) is turned on, and the signal of the data wire (DL) is transmitted to the gate electrode of the driving thin film transistor (DTr), and the driving thin film transistor ( Since DTr) is on, light is output through the organic light emitting diode (E).

At this time, when the driving thin film transistor (DTr) is in the on state, the level of the current flowing from the power wiring (PL) to the light emitting diode (E) is determined, and this causes the light emitting diode (E) to display in gray scale. can be implemented, and the storage capacitor (StgC) plays a role in maintaining the gate voltage of the driving thin film transistor (DTr) constant when the switching thin film transistor (STr) is turned off. Even if it is turned off, the level of current flowing through the light emitting diode (E) can be maintained constant until the next frame.

Figure 2 is a cross-sectional view schematically showing an organic light emitting device equipped with a general top-gate type thin film transistor.

As shown, a typical organic light emitting device 1 includes a light blocking pattern 13, a buffer layer 11, a semiconductor layer 14, an interlayer insulating film 16, a gate electrode 17, and a gate insulating film on a substrate 10. (15), source and drain electrodes (18a, 18b), protective layer (21), color filter layer (23), planarization film (25), first electrode (26), bank (29), organic light emitting layer (27), A second electrode 28 is provided.

First, a light-shielding pattern 13 is formed on the substrate 10 using a first mask, and a buffer layer 11 is formed on the entire surface above the light-shielding pattern 13.

An amorphous silicon layer is deposited on the buffer layer 11, the amorphous silicon layer is crystallized into polycrystalline silicon, and then the polycrystalline silicon layer is patterned into a predetermined pattern using a second mask.

Thereafter, the polycrystalline silicon layer patterned using the second mask is formed into a semiconductor layer ( 14) is formed.

Next, after depositing a conductive material to be used as the gate insulating film 15 and the gate electrode 17 on the buffer layer 11 and the semiconductor layer 14, the active area ( In response to 14a), the gate electrode 17 is patterned into a predetermined pattern.

At this time, although not shown in the drawing, a gate wiring (GL in FIG. 1) extending in one direction is formed.

After forming the gate electrode 17, an interlayer insulating film 16 is deposited on the gate electrode 17, and then the source and drain electrodes 18a and 18b and the semiconductor layer 14 are formed using a fourth mask. Source and drain contact holes 19 for electrical connection are patterned.

After forming the source and drain contact holes 19, source and drain electrode materials are deposited on the interlayer insulating film 16, and the source and drain electrodes 18a and 18b are patterned into a predetermined pattern using a fifth mask.

At this time, a semiconductor layer 14 including source and drain electrodes 18a and 18b and source and drain regions 14b and 14c in contact with these electrodes 18a and 18b, and a gate insulating film formed on the semiconductor layer 14. (15) and the gate electrode 17 form a driving thin film transistor (DTr).

After forming the source and drain electrodes 18a and 18b, a protective layer 21 is formed on the source and drain electrodes 18a and 18b and the interlayer insulating film 16, and a protective layer 21 is formed on the source and drain electrodes 18a and 18b. A first drain contact hole 22 for electrically connecting one electrode to the first electrode 26, which is the anode electrode of the light emitting diode, is patterned using a sixth mask.

After forming the first drain contact hole 22, red (R), green (G), and blue (B) colors are applied to the upper part of the protective layer 21 using the 7th to 9th masks for each pixel region (P). The color filter layer 23 is patterned.

After forming the planarization layer 25 on the red, green, and blue color filter layer 23, a second drain contact hole 24 is formed to expose the drain electrode 18b through the first drain contact hole 22. Patterning is performed using the 10th mask.

A conductive material is deposited on the planarization layer 25, and the conductive material is patterned using an 11th mask to form a first electrode 26 that forms an anode as a component of the light emitting diode (E). form

The first electrode 26 is electrically connected to the drain electrode 18b through the first and second drain contact holes 22 and 24.

After forming the first electrode 26, a bank 29 is formed on the planarization layer 25 and the first electrode 26 using a twelfth mask.

Afterwards, the organic light-emitting layer 27 is deposited on the first electrode 26 using a shadow mask, and then a second electrode forming the cathode of the light-emitting diode E is deposited on the organic light-emitting layer 27. 28) is deposited.

Thereafter, the organic light emitting device 1 is completed by encapsulating the upper part of the second electrode 28 through a protective film 30 in the form of a thin film.

Meanwhile, the organic light emitting device 1 including this top-gate type driving thin film transistor (DTr) requires at least 12 mask processes to form a predetermined pattern, and one mask process requires an exposure mask. Since exposure, development, and cleaning processes must be performed, as the number of mask processes increases, productivity decreases and process costs increase.

The present invention is intended to solve the above problems, and its first purpose is to simplify the manufacturing process of an organic light emitting device including a top-gate type thin film transistor.

Through this, the second purpose is to reduce process costs and improve process efficiency.

In order to achieve the object as described above, the present invention forms a light-shielding pattern as a color filter, the third region of the oxide semiconductor layer is formed to form the first electrode of the light emitting diode, and the driving region includes the first source electrode. And, the bank is located above the gate wiring and data wiring.

Through this, the present invention requires only four mask processes to form a top-gate type thin film transistor, making an organic light emitting device possible with a total of eight mask processes, including four mask processes for forming a color filter and a bank. Compared to the existing organic light emitting device manufacturing process that required 12 mask processes, 4 mask processes can be eliminated, reducing process costs and shortening process time, increasing productivity. Including, the efficiency of the process can be improved.

As described above, forming a top-gate type thin film transistor according to the present invention requires only four mask processes, and a total of eight mask processes, including four mask processes for forming the color filter and bank, are required. By forming an organic light emitting device, four mask processes can be eliminated compared to the existing organic light emitting device manufacturing process that required 12 mask processes, which has the effect of reducing process costs and shortening the process time. There is an effect that can improve the efficiency of the process, including productivity.

1 is a circuit diagram of one pixel of a general organic light emitting device.
Figure 2 is a cross-sectional view schematically showing an organic light emitting device equipped with a general top-gate type thin film transistor.
Figure 3 is a circuit diagram of one pixel area of an organic light emitting device according to an embodiment of the present invention.
Figure 4 is a plan view schematically showing a portion of the pixel area of an organic light emitting device according to an embodiment of the present invention.
Figure 5 is a cross-sectional view taken along line V-V of Figure 4.

The present invention includes a substrate in which red (R), green (G), and blue (B) pixel areas are defined by crossing gate wires and data wires, and a driving area and a light emitting area are defined for each pixel area; A first oxide semiconductor layer located corresponding to the driving region on the upper part of the substrate and including a first region in the center and second and third regions located on both sides of the first region, and the light emission from the third region a first electrode extending into the region, a gate insulating film positioned on the first and second regions of the first oxide semiconductor layer corresponding to the driving region, and a gate insulating film positioned corresponding to the first region on the gate insulating film. an interlayer insulating film having a first gate electrode, a first semiconductor contact hole located above the first gate electrode corresponding to the driving region and exposing the second region, and the first semiconductor contact hole through the first semiconductor contact hole. A first source electrode in contact with region 2, an organic light-emitting layer located above the first electrode corresponding to the light-emitting area, the driving area including the first source electrode, and upper portions of the gate wire and the data wire. An organic light emitting device is provided including a bank located at and a second electrode located above the bank and the organic light emitting layer.

At this time, a light-shielding pattern is located corresponding to the driving area on the substrate, and color filters of red (R), green (G), and blue (B) are located corresponding to the light-emitting area on the substrate, The light blocking pattern is formed by overlapping at least two of the red (R), green (G), and blue (B) color filters, and a planarization layer is located above the light blocking pattern and the red, green, and blue color filters, , the first oxide semiconductor layer is located above the planarization layer.

In addition, the third area is conductive, the light blocking pattern is located corresponding to a switching area located on one side of the driving area, and a second area is located below the gate insulating film above the light blocking pattern of the switching area. An oxide semiconductor layer, a second gate electrode located above the gate insulating layer and overlapping the second oxide semiconductor layer, and a second electrode located above the interlayer insulating layer and in contact with both sides of the second oxide semiconductor layer, respectively. It includes a source electrode, a first drain electrode, and an extension part extending from the first drain electrode and connected to the first gate electrode, wherein the extension part overlaps a second region of the first oxide semiconductor layer to form a storage capacitor. Compose.

At this time, it includes a power wire located parallel to the data wire, wherein the second gate electrode is connected to the gate wire, the second source electrode is connected to the data wire, and the first source electrode is connected to the power wire. It is connected to a wiring, and the first oxide semiconductor layer, the first gate electrode, and the first source electrode constitute a driving thin film transistor, and the second oxide semiconductor layer, the second gate electrode, and the second source electrode The first drain electrode constitutes a switching thin film transistor and is electrically connected to a reference wiring located parallel to the gate wiring, the gate wiring, the first oxide semiconductor layer, and the reference wiring to form a threshold of the driving thin film transistor. It further includes a reference thin film transistor that adjusts the voltage.

And, the bank is located above the switching area.

Hereinafter, embodiments according to the present invention will be described in detail with reference to the drawings.

Figure 3 is a circuit diagram of one pixel area of an organic light emitting device according to an embodiment of the present invention.

As shown, the organic light emitting device according to an embodiment of the present invention includes a switching thin film transistor (Tsw), a driving thin film transistor (Tdr), a reference thin film transistor (Tr), a storage capacitor (Cst), and a light emitting diode ( Includes E).

Looking at this in more detail, a gate line (GL) is formed in a first direction, and is arranged in a second direction crossing the first direction to define a pixel area (P) and a data line (DL) is formed.

In addition, it is separated from the data line (DL) and includes a power line (VDD) for applying a high potential voltage to the driving thin film transistor (Tdr) and a reference line (RL) for applying a reference voltage to the reference thin film transistor (Tr). is formed

A switching thin film transistor (Tsw), a driving thin film transistor (Tdr), a reference thin film transistor (Tr), a storage capacitor (Cst), and a light emitting diode (E) are formed in each pixel area (P).

The gate electrode and source electrode of the switching thin film transistor (Tsw) are respectively connected to the gate wire (GL) and the data wire (DL) to receive gate signals and data signals, respectively, and the gate electrode of the driving thin film transistor (Tdr) is connected to the switching thin film transistor (Tdr). It is connected to the drain electrode of the transistor (Tsw) and receives a data signal.

Here, the driving thin film transistor (Tdr) according to an embodiment of the present invention omits a separate drain electrode, and the oxide semiconductor layer becomes the first electrode forming the anode of the light emitting diode (E), and the driving thin film transistor (Tdr) The source electrode of is connected to the power wiring (VDD). The second electrode forming the cathode of the light emitting diode (E) is connected to the low potential voltage (VSS).

In addition, the reference thin film transistor (Tr) also omits a separate drain electrode, the oxide semiconductor layer of the reference thin film transistor (Tr) is connected to the oxide semiconductor layer of the driving thin film transistor (Tdr), and the gate of the reference thin film transistor (Tr) The electrode is connected to the gate wiring (GL), and the source electrode of the reference thin film transistor (Tr) is connected to the reference wiring (RL).

The first storage electrode of the storage capacitor (Cst) is electrically connected to the drain electrode of the switching thin film transistor (Tsw) and the gate electrode of the driving thin film transistor (Tdr), and the second storage electrode of the storage capacitor (Cst) is connected to the driving thin film transistor. It is electrically connected to the oxide semiconductor layer of (Tdr).

The switching thin film transistor (Tsw) switches according to the gate signal and supplies the data signal to the gate electrode of the driving thin film transistor (Tdr), and the driving thin film transistor (Tdr) switches according to the data signal to supply the current of the light emitting diode (E). Control.

At this time, the storage capacitor (Cst) maintains the charge corresponding to the data signal for one frame to keep the amount of current flowing through the light emitting diode (E) constant and the gray level displayed by the light emitting diode (E) constant. It plays a role.

Therefore, when the gate signal is applied through the gate wire (GL), the switching thin film transistor (Tsw) is turned on, and the signal of the data wire (DL) is transmitted to the gate electrode of the driving thin film transistor (Tdr). (Tdr) is switched, and light is output from the light emitting diode (E) connected to the driving thin film transistor (Tdr).

At this time, when the driving thin film transistor (Tdr) is in the on state, the level of the current flowing through the light emitting diode (E) is determined, and as a result, the light emitting diode (E) can implement gray scale. .

Additionally, the storage capacitor (Cst) serves to keep the gate voltage of the driving thin film transistor (Tdr) constant when the switching thin film transistor (Tsw) is turned off. Therefore, even if the switching thin film transistor (Tsw) is turned off, the level of current flowing through the light emitting diode (E) can be maintained constant until the next frame.

At this time, when the reference thin film transistor (Tr) is turned on, the oxide semiconductor layers of the reference thin film transistor (Tr) and the driving thin film transistor (Tdr) are connected to each other, thereby reducing the characteristic deviation of the driving thin film transistor (Tdr). can be reduced.

Here, the organic light emitting device according to an embodiment of the present invention requires only four mask processes to form a top-gate type thin film transistor, and a total of eight processes are required, including four mask processes to form a color filter and a bank. Organic light emitting devices can be formed using only a mask process.

Compared to the existing organic light emitting device manufacturing process that required 12 mask processes, this can eliminate 4 mask processes, thereby reducing process costs and shortening process time, improving process efficiency, including productivity. efficiency can be improved.

Let's look at this in more detail with reference to Figures 4 and 5.

Figure 4 is a plan view schematically showing a portion of the pixel area of an organic light emitting device according to an embodiment of the present invention.

At this time, for convenience of explanation, the area where the switching and driving thin film transistors (Tsw, Tdr) and the reference thin film transistor (Tr) are formed is called the non-emission area (DA), and the area where the light emitting diode (E in FIG. 3) is formed is called the light emitting area. It is defined as area (LA).

As shown, in the organic light emitting device 100 according to an embodiment of the present invention, a gate line (GL) and a data line (DL) intersect to define a pixel area (P). In addition, the power wire (VDD) is spaced in parallel with the data wire (DL) and intersects the gate wire (GL), and the reference wire (RL) is spaced parallel to the gate wire (GL) and intersects the data wire (DL) and the data wire (DL). It intersects with the power wiring (VDD).

The non-emission area (DA) of each pixel area (P) includes a switching thin film transistor (Tsw), a driving thin film transistor (Tdr), a reference thin film transistor (Tr), a storage capacitor (Cst), and a light emitting diode (Figure 3). E) is formed.

The driving thin film transistor (Tdr) includes a first oxide semiconductor layer 108, a first gate electrode 115, and a first source electrode 118, and the switching thin film transistor (Tsw) includes a second oxide semiconductor layer ( 109), a second gate electrode 117, a second source electrode 121, and a first drain electrode 123.

At this time, the first source electrode 118 of the driving thin film transistor (Tdr) is connected to the second region 108b (see FIG. 5) of the first oxide semiconductor layer 108 through the first semiconductor layer contact hole 119. , the second source electrode 121 and the first drain electrode 123 of the switching thin film transistor (Tsw) are connected to the second region of the second oxide semiconductor layer 109 through the second and third semiconductor layer contact holes 125. (109b, see FIG. 5) and the third area (109c, see FIG. 5), respectively.

The reference thin film transistor (Tr) includes a third oxide semiconductor layer 133, a third gate electrode 131, and a third source electrode 135.

The switching thin film transistor (Tsw) is electrically connected to the gate line (GL) and the data line (DL) and is located at their intersection point. That is, the second gate electrode 117 of the switching thin film transistor (Tsw) is connected to the gate wire (GL), and the second source electrode 121 of the switching thin film transistor (Tsw) is connected to the data wire (DL).

The first gate electrode 115 of the driving thin film transistor (Tdr) is electrically connected to the first drain electrode 123 of the switching thin film transistor (Tsw).

That is, the extension portion 123a extending from the first drain electrode 123 of the switching thin film transistor (Tsw) and the first gate electrode 115 of the driving thin film transistor (Tdr) contact through the gate contact hole 132. , the first gate electrode 115 of the driving thin film transistor (Tdr) is electrically connected to the first drain electrode 123 of the switching thin film transistor (Tsw).

In other words, the extension portion 123a of the first drain electrode 123 of the switching thin film transistor (Tsw) and the first gate electrode 115 of the driving thin film transistor (Tdr) come into contact with each other.

In addition, the first source electrode 118 of the driving thin film transistor (Tdr) is connected to the power wiring (VDD), and the first oxide semiconductor layer 108 of the driving thin film transistor (Tdr) is connected to the first source electrode 118 of the reference thin film transistor (Tr). 3 Connected to the oxide semiconductor layer 133.

Here, the driving thin film transistor (Tdr) and the reference thin film transistor (Tr) are seen to share the oxide semiconductor layers (108, 133), but unlike this, the first oxide semiconductor layer (108) of the driving thin film transistor (Tdr) The third oxide semiconductor layers 133 of the reference thin film transistor (Tr) may be formed to be spaced apart from each other and electrically connected to each other.

The third gate electrode 131 of the reference thin film transistor (Tr) is connected to the gate wire (GL), and the third source electrode 135 of the reference thin film transistor (Tr) is connected to the reference wire (RL).

Here, the reference thin film transistor (Tr) and the reference wiring (RL) can be omitted.

The storage capacitor (Cst) includes a first storage electrode made of a conductive region of the second region 108b of the first oxide semiconductor layer 108 and the third oxide semiconductor layer 133, and a switching thin film transistor (Tsw). It includes a second storage electrode consisting of an extension portion 123a extending from the first drain electrode 123, and an interlayer insulating film 113 (see FIG. 5) located between the first and second storage electrodes as a dielectric layer.

The organic light emitting device 100 according to an embodiment of the present invention includes a first electrode 128 (see FIG. 5) extending from the first oxide semiconductor layer 108 of the driving thin film transistor (Tdr), and a first electrode 128. , see FIG. 5), an organic light emitting layer (129, see FIG. 5) and a second electrode (130, see FIG. 5) are located at the top, forming an organic light emitting device 100 including a light emitting diode (E in FIG. 3). do.

Here, the first electrode 128 (see FIG. 5) extending from the first oxide semiconductor layer 108 is a component of the light emitting diode (E in FIG. 3) and forms an anode, and the second electrode (130, see FIG. 5) forms a cathode.

Meanwhile, the organic light emitting device 100 according to an embodiment of the present invention uses a bottom emission method in which light emitted from the organic light emitting layer 129 (see FIG. 5) is emitted toward the first electrode 128 (see FIG. 5). type).

At this time, red (R), green (G), and blue (B) color filters 105 are placed on the upper part of the substrate 110 (see FIG. 5) corresponding to the light emitting area (LA) of each pixel area (P). When positioned respectively, the organic light emitting devices 100 of the present invention emit R, G, and B colors for each pixel area (P), thereby realizing full color.

In addition, a light blocking pattern 103 is located on the top of the substrate 110 (see FIG. 5) corresponding to the non-emission area (DA) of the pixel area (P), and a driving thin film transistor (Tdf) is placed on top of the light blocking pattern 103. , a switching thin film transistor (Tsw), a reference thin film transistor (Tr), and a storage capacitor (Cst) are located.

The light blocking pattern 103 according to an embodiment of the present invention is formed by overlapping color filters of at least two colors among red (R), green (G), and blue (B) color filters 105.

The organic light-emitting device 100 according to an embodiment of the present invention can be formed through an 8-mask process. First, the light-shielding pattern 103 is formed using red (R), green (G), and blue (B) color filters ( In the process of forming 105), at least two of the red (R), green (G), and blue (B) color filters 105 are overlapped to form a separate light blocking pattern 103. One mask process can be omitted.

In addition, a red (R), green (G), and blue (B) color filter 105 and a light blocking pattern 103 are formed on the substrate 110 (see FIG. 5), and a planarization layer 107, By forming (see FIG. 5), there is no need to form a second drain contact hole (24 in FIG. 2) like the existing planarization layer (25 in FIG. 2), and thus one mask process can be omitted.

In addition, the first electrode 128 (see FIG. 5) of the light emitting diode (E in FIG. 3) is made of an extension extending from the first oxide semiconductor layer 108, so that the first electrode 128 (see FIG. 5) is One mask process for forming can be omitted.

In addition, a bank 127 (FIG. 5) is formed at the boundary of each pixel area (P) above the switching thin film transistor (Tsw), driving thin film transistor (Tdr), reference thin film transistor (Tr), and each gate and data wire (GL, DL). By forming the protective layer (21 in FIG. 2) with a separate first drain contact hole (22 in FIG. 2), it is possible to omit one mask process.

Let's take a closer look at this with reference to the cross-sectional view of FIG. 5.

Figure 5 is a cross-sectional view taken along line V-V of Figure 4.

At this time, for convenience of explanation, the area where the switching and driving thin film transistor is formed is defined as the non-emission area (DA), and the area where the light emitting diode (E in FIG. 3) is formed is defined as the light emitting area (LA).

Additionally, the area where the switching thin film transistor (Tsw) is formed will be defined as the switching area (SWA), and the area where the driving thin film transistor (Tdr) will be formed will be defined as the driving area (DRA).

As shown, the organic light emitting device 100 is formed by encapsulating a substrate 110 on which a driving thin film transistor (DTr), a switching thin film transistor (Tsw), and a light emitting diode (E) are formed by a protective film 140. )do.

That is, a light-shielding pattern 103 is formed on the transparent substrate 110 to block the transmission of light corresponding to the non-emission area (DA) in each pixel area (P).

The light blocking pattern 103 is formed by overlapping at least two color filters 105 of red (R), green (G), and blue (B).

At this time, in response to the light emitting area (LA) within each pixel area (P), the red (R), green (G), and blue (B) color filters 105 are sequentially repeated for each pixel area (P). A color filter layer is formed.

A planarization layer 107 is formed on the light blocking pattern 103 and the color filter 105.

The planarization layer 107 is to compensate for the level difference caused by the formation of the color filter 105 and is formed using a transparent resin such as acrylic epoxy with insulating properties.

In addition, a first oxide semiconductor layer 108 is formed on the planarization layer 107 corresponding to the driving area (DRA) of the non-emission area (DA), and the first oxide semiconductor layer 108 is It is defined by being divided into area 1 (108a) and second and third areas (108b, 108c) on both sides of the first area (108a). The first area (108a) overlaps the first gate electrode (115) and is driven. It forms the channel of the thin film transistor (Tdr).

Additionally, the second and third regions 108b and 108c have conductor properties due to reduced oxide semiconductor material.

In addition, a second oxide semiconductor layer 109 is formed corresponding to the switching area (SWA) of the non-emission area (DA), and the second oxide semiconductor layer 109 also includes a first area 109a in the center, and a first area 109a in the center thereof. Area 1 (109a) is divided into second and third areas (109b, 109c) on both sides.

At this time, the oxide semiconductor material in the second and third regions 109b and 109c of the second oxide semiconductor layer 109 is also reduced and has conductive properties.

In particular, the organic light emitting device 100 according to an embodiment of the present invention is formed so that the third region 108c of the first oxide semiconductor layer 108 extends to the light emitting area LA where the light emitting diode E is formed. It is characterized by

The third region 108c of the first oxide semiconductor layer 108 extending to the light emitting area LA serves as the first electrode 128 forming the anode of the light emitting diode E.

In addition, a gate insulating film 111 is formed on the first and second oxide semiconductor layers 108 and 109 of the switching area (SWA) and driving area (DRA), and the first and second oxide semiconductor layers 111 are formed on the gate insulating film 111. First and second gate electrodes 115 and 117 are formed respectively corresponding to the first regions 108a and 109a of the second oxide semiconductor layers 108 and 109, and although not shown in the drawing, a gate wiring extending in one direction. (GL in Figure 4) is formed.

At this time, the gate insulating film 111 is formed to cover only the upper portions of the first and second regions 108a and 108b of the second oxide semiconductor layer 109 and the first oxide semiconductor layer 108, and is formed as the light emitting area LA. The upper portion of the third region 108c of the extended first oxide semiconductor layer 108 is exposed.

And an interlayer insulating film 113 is formed on the first and second gate electrodes 115 and 117 and the gate wiring (GL in FIG. 4), and the interlayer insulating film 113 and the gate insulating film 111 below it are the first and second gate electrodes 115 and 117, respectively. A first semiconductor layer contact hole 119 exposing the second region 108b of the oxide semiconductor layer 108, and exposing the second and third regions 109b and 109c of the second oxide semiconductor layer 109. It includes second and third semiconductor layer contact holes 125.

At this time, the interlayer insulating film 113 is also formed to cover only the upper portions of the first and second regions 108a and 108b of the second oxide semiconductor layer 109 and the first oxide semiconductor layer 108, so as to cover the light emitting area LA. The third region 108c of the first oxide semiconductor layer 108 is exposed.

Next, the first layer exposed through the first semiconductor layer contact hole 119 corresponding to the driving area DRA on the upper part of the interlayer insulating film 113 including the first to third semiconductor layer contact holes 119 and 125. A first source electrode 118 is formed in contact with the second region 108b of the oxide semiconductor layer 108.

At this time, the first oxide semiconductor layer 108 including the first source electrode 118 and the second region 108b in contact with the first source electrode 118, and the upper portion of the first oxide semiconductor layer 108. The gate insulating film 111 and the first gate electrode 115 formed form a driving thin film transistor (Tdr).

In addition, the second and third regions 109b of the second oxide semiconductor layer 109 are exposed through the second and third semiconductor layer contact holes 125 on the interlayer insulating film 113 corresponding to the switching area SWA. , 109c), and a second source electrode 121 and a first drain electrode 123 are formed, respectively.

At this time, the second source electrode 121 and the first drain electrode 123, the second oxide semiconductor layer 109, the gate insulating film 111 formed on the second oxide semiconductor layer 109, and the second gate The electrode 117 forms a switching thin film transistor (Tsw).

Here, although not shown in the drawing, the first gate electrode 115 of the driving thin film transistor (Tdr) is connected to the first drain electrode 123 of the switching thin film transistor (Tsw), and the first gate electrode 115 of the driving thin film transistor (Tdr) is connected to the first drain electrode 123 of the switching thin film transistor (Tsw). 1 The source electrode 118 is connected to the power wiring (VDD in FIG. 4).

In addition, a data line (DL in FIG. 4) that intersects the gate line (GL in FIG. 4) and defines the pixel area (P) is formed on the interlayer insulating film 113.

And, an organic layer is formed on the first source electrode 118 of the driving area (DRA) and the second source electrode 121 and the first drain electrode 123 of the switching area (SWA) as a boundary for each pixel area (P). A bank 127 made of material is located. As shown in FIG. 5, the drain electrode connected to the third region 108c of the first oxide semiconductor layer 108 is not formed in the driving area DRA, and the bank 127 is connected to the first gate electrode 115. It is in direct contact with the interlayer insulating film 113 located on the side.

The bank 127 is located on an area where a switching thin film transistor (Tsw), a driving thin film transistor (Tdr), and gate wires (GL in FIG. 4) and data wires (DL in FIG. 4) are formed to define the pixel area (P). is formed, and the area exposed by the bank 127 becomes a light emitting area LA that substantially emits light.

Then, the organic light emitting layer 129 of the light emitting diode (E) is formed on the entire surface of the substrate 101 including the third region 108c of the first oxide semiconductor layer 108 in the light emitting area LA.

Here, the organic light-emitting layer 129 may be composed of a single layer made of a light-emitting material, and may include a hole injection layer, a hole transport layer, an emitting material layer, and an electron layer to increase light-emitting efficiency. It may be composed of multiple layers of an electron transport layer and an electron injection layer.

And, on the front surface of the substrate 110 above the bank 127 formed on the driving area (DRA) and the switching area (SWA) and the organic light emitting layer 129 formed on the light emitting area (LA), a cathode forming Two electrodes 130 are formed.

Here, the first electrode 128, the organic light emitting layer 129, and the second electrode 130 consisting of the third region 108c of the first oxide semiconductor layer 108 extending to the light emitting area LA are light emitting diodes ( E) is achieved. As shown in FIGS. 4 and 5, one edge of the first electrode 128 overlaps the power line VDD.

Therefore, when a predetermined voltage is applied to the first electrode 128 and the second electrode 130, holes injected from the first electrode 128 and electrons provided from the second electrode 130 are transferred to the organic light emitting layer 129. It is transported to form excitons, and when these excitons transition from the excited state to the ground state, light is generated and emitted in the form of visible light.

At this time, since the emitted light passes through the transparent first electrode 128 and goes out, the organic light emitting device 100 implements an arbitrary image.

A protective film 140 in the form of a thin film is formed on the switching and driving thin film transistors (Tsw, Tdr) and the light emitting diode (E), and the organic light emitting device 100 is encapsulated through the protective film 140. (encapsulation), the protective film 140 is used by stacking at least two inorganic protective films to prevent external oxygen and moisture from penetrating into the organic light emitting device 100. At this time, there is a gap between the two inorganic protective films. It is desirable to include an organic protective film to supplement the impact resistance of the inorganic protective film.

The organic light-emitting device 100 according to an embodiment of the present invention uses the light-shielding pattern 103 to form a red (R), green (G), and blue (B) color filter 105. By overlapping and forming at least two of the color filters 105 of R), green (G), and blue (B), a separate mask process for forming the light blocking pattern 103 can be omitted. there is.

In addition, by forming a red (R), green (G), and blue (B) color filter 105 and a light blocking pattern 103 on the upper part of the substrate 110, and forming a planarization layer 107 on the upper part, Since there is no need to form a second drain contact hole (24 in FIG. 2) like the existing planarization layer (25 in FIG. 2), one mask process can be omitted.

In addition, the first electrode 128 of the light emitting diode (E) is made of an extension extending from the first oxide semiconductor layer 108, thereby forming a single electrode 128 of the light emitting diode (E). The mask process can be omitted.

In addition, a bank 127 is formed at the boundary of each pixel area (P) above the switching thin film transistor (Tsw), driving thin film transistor (Tdr), reference thin film transistor (Tr), and each gate and data wire (GL, DL). By doing so, the protective layer (21 in FIG. 2) having a separate first drain contact hole (22 in FIG. 2) can be omitted, and thus one mask process can be omitted.

Through this, process costs can be reduced, process time can be shortened, and process efficiency, including productivity, can be improved.

The present invention is not limited to the above embodiments, and can be implemented with various changes without departing from the spirit of the present invention.

100: Organic light emitting device
103: light blocking pattern, 105: color filter, 107: flattening layer
108: first oxide semiconductor layer (108a, 108b, 108c: first to third regions)
109: second oxide semiconductor layer (109a, 109b, 109c: first to third regions)
110: substrate
111: gate insulating film, 113: interlayer insulating film, 115: first gate electrode
117: second gate electrode, 118: first source electrode
119: first semiconductor layer contact hole
121: second source electrode, 123: first drain electrode, 125: second and third semiconductor layer contact holes
127: bank
128: first electrode, 129: organic light emitting layer, 130: second electrode (E: light emitting diode)
140: protective film
P: Pixel area, DA: Non-emissive area, LA: Emitting area
DRA: driving area, SWA: switching area

Claims (10)

A substrate where gate wires and data wires intersect to define red (R), green (G), and blue (B) pixel areas, and a driving area and a light emitting area are defined for each pixel area;
a first oxide semiconductor layer located corresponding to the driving region on the upper part of the substrate and including a first region in the center and second and third regions located on both sides of the first region;
a first electrode extending from the third area to the light emitting area;
a light-shielding pattern located between the substrate and the first oxide semiconductor layer in the driving area;
In the light emitting area, red (R), green (G), and blue pixel areas correspond to each of the red (R), green (G), and blue (B) color pixel areas and are located between the substrate and the first electrode. (B) a color filter;
a gate insulating film positioned on the first and second regions of the first oxide semiconductor layer corresponding to the driving region;
a first gate electrode positioned corresponding to the first region on the gate insulating film;
an interlayer insulating film located above the first gate electrode corresponding to the driving area and having a first semiconductor contact hole exposing the second area;
a power wire located on the interlayer insulating film and parallel to the data wire;
a first source electrode located on the interlayer insulating film, extending from the power wiring, and contacting the second region through the first semiconductor contact hole;
an organic light-emitting layer located above the first electrode corresponding to the light-emitting area;
the driving area including the first source electrode, and a bank located above the gate wire and the data wire;
It includes a second electrode located above the bank and the organic light-emitting layer,
The light blocking pattern is formed by overlapping at least two of the red (R), green (G), and blue (B) color filters,
A planarization layer covering the light-shielding pattern and the color filter is formed on the upper part of the substrate, and the first oxide semiconductor layer and the first electrode are located on the planarization layer,
One edge of the first electrode overlaps the power wiring,
An organic light emitting device in which light from the organic light emitting layer passes through the red (R), green (G), and blue (B) color filters and displays red, blue, and blue colors.

delete delete delete According to claim 1,
The third region is a conductive organic light emitting device.
According to claim 1,
The light blocking pattern is located corresponding to a switching area located on one side of the driving area, and a second oxide semiconductor layer located below the gate insulating film on top of the light blocking pattern in the switching area;
a second gate electrode located above the gate insulating film and overlapping the second oxide semiconductor layer;
a second source electrode and a first drain electrode located above the interlayer insulating film and in contact with both sides of the second oxide semiconductor layer, respectively;
It includes an extension portion extending from the first drain electrode and connected to the first gate electrode,
The extended portion overlaps the second region of the first oxide semiconductor layer to form a storage capacitor.
According to claim 6,
An organic light emitting device wherein the second gate electrode is connected to the gate wire, and the second source electrode is connected to the data wire.
According to claim 6,
The first oxide semiconductor layer, the first gate electrode, and the first source electrode constitute a driving thin film transistor,
The second oxide semiconductor layer, the second gate electrode, the second source electrode, and the first drain electrode constitute a switching thin film transistor,
The organic light emitting device further includes a reference line positioned parallel to the gate line, and a reference thin film transistor electrically connected to the gate line, the first oxide semiconductor layer, and the reference line to adjust the threshold voltage of the driving thin film transistor. device.
According to claim 6,
The bank is an organic light emitting device located above the switching area.
According to claim 1,
The bank is an organic light emitting device in direct contact with the interlayer insulating film located on a side of the first gate electrode.

Images