KR20100011034A - Method of fabricating organic electroluminescent device - Google Patents

Abstract

PURPOSE: A method for manufacturing an organic electroluminescent device is provided to prevent the lowering of display quality by preventing the damage to the organic light emitting layer due to a plasma atmosphere. CONSTITUTION: A switching thin film transistor and a driving thin-film transistor are formed on a substrate(101). A first electrode(140) is formed on each pixel region. The first electrode is contacted with one electrode of the driving thin film transistor. A partition(145) is formed on the boundary of the pixel region. The partition is overlapped with the girth of the first electrode. An organic light emitting layer(150) is formed on the fist electrode. A second electrode is formed by transferring the transfer layer of the transfer substrate(170) to the substrate. The second electrode is contacted with the partition and the organic light emitting layer.

Description

Manufacturing method of organic electroluminescent device {Method of fabricating organic electroluminescent device}

The present invention relates to an organic electroluminescent device, and more particularly to a method for manufacturing an organic electroluminescent device which can improve display quality by preventing dark spots caused by damage to the organic light emitting layer. It is about.

The organic light emitting diode, which is one of the flat panel displays (FPDs), has high luminance and low operating voltage characteristics. In addition, the self-luminous self-illuminating type provides high contrast ratio, enables ultra-thin display, easy response time with several microsecond response time, no restriction on viewing angle, and stable at low temperatures. Since it is driven at a low voltage of 5 to 15V DC, it is easy to manufacture and design a driving circuit.

The organic light emitting diode having such characteristics is largely divided into a passive matrix type and an active matrix type. In the passive matrix method, a scan line and a signal line cross each other to form a device in a matrix form, and each pixel Since the scan lines are sequentially driven over time in order to drive, the instantaneous luminance must be equal to the average luminance multiplied by the number of lines in order to represent the required average luminance.

However, in the active matrix method, a thin film transistor, which is a switching element for turning on / off a pixel region, is positioned for each pixel region, and one electrode of the switching thin film transistor is provided. And a driving thin film transistor formed thereon, and an anode electrode connected to one electrode of the driving thin film transistor is turned on / off in each pixel region, and the cathode electrode is opposed to the anode electrode. It is formed on the whole substrate.

In the active matrix method, a voltage applied to each pixel region is charged in a storage capacitor, and power is applied until the next frame signal is applied, thereby irrespective of the number of scan lines. Run one screen continuously. Accordingly, since low luminance, high definition, and large size can be obtained even when low current is applied, an active matrix type organic light emitting diode has been mainly used in recent years.

Hereinafter, the basic structure and operation characteristics of the active matrix organic light emitting diode will be described with reference to the drawings.

1 is a schematic circuit diagram of one pixel area of a general active matrix organic light emitting diode.

As illustrated, one pixel area of the active matrix organic light emitting display device is a switching thin film transistor STr, a driving thin film transistor DTr, a storage capacitor StgC, and an organic light emitting diode E )

That is, the gate line GL is formed in the first direction, is formed in the second direction crossing the first direction to define the pixel region P, and the data line DL is formed. A power supply wiring PL is spaced apart from the DL) to apply a power supply voltage.

In addition, a switching thin film transistor STr is formed at a portion where the data line DL intersects the gate line GL, and is electrically connected to one electrode of the switching thin film transistor STr and is a driving thin film transistor DTr. ) Is formed.

In this case, the driving thin film transistor DTr is electrically connected to the organic light emitting diode E. That is, the first electrode, which is one terminal of the organic light emitting diode E, is connected to the drain electrode of the driving thin film transistor DTr, and the second electrode, which is the other terminal, is connected to the power supply line PL. In this case, the power line PL transfers a power supply voltage to the organic light emitting diode E.

In addition, a storage capacitor StgC is formed between the gate electrode and the drain electrode of the driving thin film transistor DTr.

Therefore, when a signal is applied through the gate line GL, the switching thin film transistor STr is turned on, and the signal of the data line DL is turned on through the switching thin film transistor STr through the driving thin film transistor DTr. Since the driving thin film transistor DTr is turned on, the light is output through the organic light emitting diode E. At this time, when the driving thin film transistor DTr is in an on state, the level of the current flowing from the power supply line PL to the organic light emitting diode E is determined, and thus the organic light emitting diode E is The gray scale may be implemented, and the storage capacitor StgC maintains the gate voltage of the driving thin film transistor DTr constant when the switching thin film transistor STr is turned off. As a result, even when the switching thin film transistor STr is turned off, the level of the current flowing through the organic light emitting diode E may be maintained until the next frame.

The organic light emitting device for driving such a current is classified into a top emission type and a bottom emission type according to a transmission direction of light emitted through the organic light emitting diode.

2 is a schematic cross-sectional view of a conventional organic light emitting device.

As shown in the drawing, the first and second substrates 10 and 30 are disposed to face each other, and the edges of the first and second substrates 10 and 30 are sealed by a seal pattern 40. Each pixel region driving thin film transistor DTr is formed on the first substrate 10. In addition, a first electrode 12 is formed to be connected to each of the driving thin film transistors DTr, and an upper portion of the first electrode 12 is connected to the driving thin film transistor DTr and is formed of red (14a) and green. The organic light emitting layer 14 emitting blue 14c and blue 14c colors is separated and separated by the partition wall 15, and the second electrode 16 is formed on the entire surface of the organic light emitting layer 14. In this case, the first and second electrodes 12 and 16 serve to apply an electric field to the organic light emitting layer 14, and the first and second electrodes 12 and 16 respectively use an anode electrode and a cathode electrode. It may be achieved, or vice versa.

Meanwhile, the second electrode 16 and the second substrate 30 formed on the entire surface of the first substrate 10 by the seal pattern 40 described above are spaced apart from each other by a predetermined interval. At this time, the space between the first substrate 10 and the second substrate 30 is characterized by forming an atmosphere of inert gas or vacuum. In addition, a moisture absorbent (not shown) is further provided to block moisture to the inside of the seal pattern 40 to prevent deterioration of the organic light emitting layer 14 which is very vulnerable to oxygen or moisture.

In the organic light emitting diode having the above structure, when the first electrode 12 is formed of a cathode and the second electrode 16 is formed of an anode, the first electrode 12 is formed of one. A low-function metal material is selected from aluminum or an aluminum alloy, for example, and the second electrode 16 is made of indium tin oxide (ITO) or indium zinc oxide (IZO), a material having a high work function. The organic light emitting layer may be formed in multiple layers to maximize luminous efficiency.

Meanwhile, in manufacturing the organic light emitting diode having the above-described structure, both the first electrode and the second electrode are formed by vacuum deposition using a shadow mask or sputtering through a sputtering device in a vacuum atmosphere.

However, in recent years, the display area has become large in size, and in order to manufacture a display device having such a large area, an enlargement of equipment becomes essential. In this case, the shadow mask, which is used to form the first electrode and the second electrode and has an area larger than that of the substrate in proportion to the area of the substrate, has a weight of 400 kg or more, so when it is mounted or replaced with another shadow mask, It takes a lot of time, and even in the progress of the vacuum deposition process using the same occurs, the error is severely generated.

In addition, sputtering is not a problem for the formation of the first electrode, but when forming the second electrode formed on the organic light emitting layer, a plasma must be formed inside the vacuum chamber due to the sputtering property, and in this process, the plasma is exposed. In the organic light emitting layer, internal damage occurs, and the damaged portion becomes a dark spot, which causes a problem of lowering display quality.

The present invention has been made to solve the above problems, an object of the present invention is to provide a method of manufacturing an organic light emitting device that can prevent the occurrence of dark spots of the organic light emitting layer by not damaging the organic light emitting layer.

According to an aspect of the present invention, there is provided a method of manufacturing an organic light emitting device, including: preparing a transfer substrate having a sequentially stacked absorbing layer, a sacrificial layer, and a transfer layer; Forming a gate wiring and a data wiring crossing the substrate to define a pixel region, a switching thin film transistor connected to the gate and the data wiring in each pixel region, and a driving thin film transistor connected to one electrode of the switching thin film transistor. Steps; Forming a first electrode in each pixel region in contact with one electrode of the driving thin film transistor; Forming barrier ribs overlapping edges of the first electrode on the boundary of each pixel region; Forming an organic emission layer over each of the first electrodes in each pixel region; Positioning the substrate and the transfer substrate such that the organic light emitting layer and the transfer layer are spaced apart and face each other; Irradiating a laser beam from one side to the other side in a vacuum atmosphere to transfer the transfer layer to a substrate on which the organic light emitting layer is formed, thereby forming a second electrode contacting the barrier rib and the organic light emitting layer. The absorption layer serves to convert light energy into thermal energy, and the sacrificial layer has a property of weakening adhesion to the transfer layer when heated.

The height difference between the surface of the organic light emitting layer and the top end of the partition wall is several hundreds of micrometers to 1 μm.

The preparing of the transfer substrate may include forming the absorbing layer by depositing a metal material selected from molybdenum (Mo), silver (Ag), and aluminum (Al) on the transparent substrate; Forming the sacrificial layer by applying an organic material on the absorber layer; Forming the transfer layer by depositing indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) over the sacrificial layer.

Forming a protective layer on a front surface of the driving thin film transistor having a contact hole exposing one electrode of the driving thin film transistor before forming the first electrode.

According to still another aspect of the present invention, there is provided a method of manufacturing an organic light emitting display device, including: preparing a transfer substrate having a sequentially stacked absorbing layer, a sacrificial layer, and a patterned transfer layer; A gate line and a data line intersecting each other on the first substrate to define a pixel area, a switching thin film transistor connected to the gate and data line in each pixel area, and a driving thin film transistor connected to one electrode of the switching thin film transistor. Forming; Forming a first electrode on an entire surface of an inner surface of a second substrate corresponding to the first substrate; Forming barrier ribs on the boundary of each pixel area over the first electrode; Forming an organic light emitting layer on the first electrode in each pixel region surrounded by the partition wall; Positioning the second substrate and the transfer substrate such that the organic light emitting layer and the patterned transfer layer are spaced apart and face each other; Irradiating a laser beam from one side to the other side in a vacuum atmosphere to transfer the patterned transfer layer to a substrate on which the organic light emitting layer is formed to form a second electrode contacting the organic light emitting layer for each pixel region. Steps; Bonding the first substrate and the second substrate to electrically connect one electrode of the driving thin film transistor to the second electrode, wherein the absorption layer serves to convert light energy into thermal energy, and the sacrificial layer When the heat is applied, the adhesive force with the patterned transfer layer is weakened.

The preparing of the transfer substrate may include forming the absorbing layer by depositing a metal material selected from molybdenum (Mo), silver (Ag), and aluminum (Al) on the transparent substrate; Forming the sacrificial layer by applying an organic material on the absorber layer; Depositing and patterning indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) over the sacrificial layer to form the patterned transfer layer.

The method may further include forming a protective layer having a contact hole exposing one electrode of the driving thin film transistor on a front surface of the driving thin film transistor; Forming a columnar spacer in each pixel area over the passivation layer; Forming a connection electrode in each pixel region by completely covering the spacer and contacting one electrode of the driving thin film transistor through the contact hole, and electrically connecting the first electrode and the second electrode of the driving thin film transistor. The connection is characterized in that the connecting electrode and the second electrode formed to cover the spacer is in contact.

In an embodiment, the forming of the organic light emitting layer may include an electron injection layer, an electron transporting layer, an organic light emitting material layer, and a hole transporting layer. sequentially depositing a transporting layer) and a hole injection layer.

In the method of manufacturing the organic light emitting device according to the present invention, since the second electrode in contact with the organic light emitting layer is not formed by sputtering, it is possible to prevent damage to the inside of the organic light emitting layer due to exposure to plasma, thereby generating a dark spot phenomenon. It is effective in preventing quality deterioration. Furthermore, there is an effect of reducing the shortening of the life due to damage of the organic light emitting layer.

In addition, it is possible to apply to a large-area substrate without a shadow mask having a weight of 400Kg or more due to the large-area has an advantage of facilitating the manufacture of an organic light emitting device having a large area.

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

3A to 3G are cross-sectional views illustrating manufacturing steps of one pixel area including a driving thin film transistor and an organic light emitting diode of an organic light emitting diode according to a first embodiment of the present invention. In this case, for convenience of description, a region in which the driving thin film transistor is formed is defined as a driving region and a region in which a light emitting diode is formed as a light emitting region.

First, as shown in FIG. 3A, a gate wiring (not shown) and a data wiring 120 defining a pixel region P are formed on the substrate 101 to cross each other, and the gate and data wiring (not shown) are formed. Switching thin film transistors (not shown) connected to these two wires (not shown) and driving thin film transistors DTr connected to one electrode of the switching thin film transistors (not shown). To form. Since the gate and data lines (not shown) 120 and the switching and driving thin film transistors (not shown, DTr) are formed according to a general method, a detailed description thereof will be omitted. In the figure, a semiconductor layer 105 including an active region 105a and an impurity doped region 105b using polysilicon is formed thereon, and a gate insulating film 108, a gate electrode 113, and an interlayer insulating film 117 are disposed thereon. And a top gate structure thin film transistor DTr including source and drain electrodes 125 and 128 in contact with and spaced apart from the impurity doped region 105b of the semiconductor layer 105, respectively. It is obvious that the structure of the thin film transistor can be variously changed and changed. For example, a thin film transistor having a bottom gate structure having a stacked structure of a source electrode and a drain electrode spaced apart from each other and a semiconductor layer including a gate electrode, a gate insulating layer, an active layer of pure amorphous silicon, and an ohmic contact layer of impurity amorphous silicon may be formed. .

Next, an inorganic insulating material such as silicon oxide (SiO ₂ ) or silicon nitride (SiNx) is deposited on the driving and switching thin film transistor (DTr), or an organic insulating material such as benzocyclobutene (BCB) or The protective layer 133 is formed by applying photo acryl, and the mask process is performed to thereby drain electrode 128 of the driving thin film transistor DTr (drain electrode in the drawing, but this is a thin film transistor). The contact hole 135 exposing the source electrode may be formed.

Next, as shown in FIG. 3B, a metal material having a low work function value, for example, aluminum (Al) or aluminum alloy (AlNd), is sputtered on the protective layer 133 on which the contact hole 135 is formed. A metal layer (not shown) is deposited to form a metal layer, and patterning is performed by performing a mask process including a series of unit processes such as application of photoresist, exposure using an exposure mask, development of exposed photoresist, etching and stripping, and the like. As a result, the first electrode 140 may be formed in contact with the drain electrode 128 of the driving thin film transistor DTr through the contact hole 135 and separated by each pixel region P. Referring to FIG. In this case, since the organic light emitting layer is not formed yet, the first electrode 140 separated for each pixel region P is not a problem even if it is formed by sputtering. In this case, the first electrode 140 serves as a cathode.

Next, as illustrated in FIG. 3C, the gate line (not shown) and the data line are disposed on an edge of the protective layer 133 and the first electrode 140 exposed to the outside of the first electrode 140. Corresponding to the 120 to form the partition wall 145. In this case, the partition wall 145 captures each pixel area P, and the first electrode 140 is exposed in the pixel area P surrounded by the partition wall 145.

Next, as shown in FIG. 3D, the organic light emitting material emits red, green, and blue light to each pixel region P through the nozzle coating or the inkjet coating on the substrate 101 on which the barrier rib 145 is formed. The organic emission layer 150 is formed. In this case, the height of the organic light emitting layer 150 may be equal to or smaller than the height of the barrier rib 145. At this time, the height of the organic light emitting layer 150 is about 90% to 98% of the height of the partition 145, more precisely the height difference between the top end of the partition 145 and the surface of the organic light emitting layer 150 hundreds It is preferable to form so that it may become about 1 micrometer-1 micrometer. The reason for forming the height of the organic light emitting layer 150 to be similar to the height of the partition wall 145 is to form the second electrode to be formed later and the surface of the organic light emitting layer 150 is in close contact.

In this case, although the organic light emitting layer 150 is illustrated as having a single layer structure, the organic light emitting layer 150 may be formed to have a multilayer structure in order to increase light emission efficiency. That is, an electron injection layer (not shown), an electron transporting layer (not shown), a light emitting layer (not shown), a hole transporting layer (not shown), and a hole injection layer (hole) It may be formed to have a five-layer structure of an injection layer (not shown). In this case, these five-layer material layers are collectively referred to as an organic light emitting layer 150, and the height of the organic light emitting layer 150 having a multilayer structure in the same manner as forming a single layer structure is also 90% of the height of the barrier rib 145. It is preferable to make it into about% to 98%.

Next, as shown in FIG. 3E, the laser beam is irradiated onto the transparent glass substrate 170 corresponding to the substrate 101 on which the organic light emitting layer 150 is formed in the vacuum chamber 190 having a vacuum atmosphere. Absorption layer 173 capable of converting light energy into thermal energy and sacrificial layer 176 made of organic materials and transparent conductive materials having high work function values, such as indium tin oxide (ITO) or indium zinc oxide (IZO) The transfer substrate 170, which is formed of a transfer layer 179 is formed so that the transfer layer 179 and the organic light emitting layer 150 face each other.

Next, as shown in FIG. 3F, the organic light emitting layer 150 facing each other and the substrate 101 on which the transfer substrate 170 and the organic light emitting layer 150 that face each other in the vacuum chamber 190 are formed. The transfer layer 179 is approached to be spaced apart by a few hundred ㎛ to several mm. Thereafter, the transfer substrate 170 is irradiated as if the laser beam LB having a specific wavelength band and energy density is scanned from one end to the other through the laser irradiation device 193. In this case, the wavelength band and the energy density of the laser beam may vary depending on the material of the absorption layer 173 of the transfer substrate 170. The absorbing layer 173 mainly prevents the transmission of light and has excellent ability to absorb the irradiated laser beam LB and convert it into thermal energy such as molybdenum (Mo), silver (Ag), and aluminum (Al). It is preferably made of one.

The absorption layer 173 corresponding to the portion irradiated with the laser beam LB by the irradiation of the laser beam LB emits heat by converting light energy of the irradiated laser beam LB into thermal energy. In this case, heat emitted from the absorbing layer 173 is transferred to the sacrificial layer 176 made of the organic material, and the sacrificial layer 176 has a weakened adhesive force on the surface thereof, so that the transfer layer 179 It is gradually separated from the sacrificial layer 176. In this case, the transfer layer 179 separated from the sacrificial layer 176 contacts the organic light emitting layer 150 and the partition wall 145 and is transferred to the substrate 101 on which the organic light emitting layer 150 is formed.

At this time, since all of these processes proceed in a vacuum atmosphere inside the chamber 190, there is no room for an air layer to be interposed between the transferred transfer layer 179 and the organic light emitting layer 150. In addition, since the transfer layer 179 is made of a conductive material itself, the transfer layer 179 has a ductile property, and has a temperature higher than room temperature by heat transferred through the sacrificial layer 176, so that the organic light emitting layer 150 and the partition wall ( 145) comes in close contact with each other. In this case, the partition wall 145 is formed a predetermined interval higher than the height of the organic light emitting layer 150, but the height difference between the partition wall 145 and the organic light emitting layer 150 is a few hundred Å to about 1㎛ and the thickness of this The difference is overcome by the ductile property of the transfer layer 179 without difficulty, it is possible to be in full contact. In addition, after the transfer layer 179 of the transparent conductive material is transferred to the substrate 101 on which the organic light emitting layer 150 is formed, the transfer layer 179 moves from the vacuum atmosphere of the vacuum chamber 190 to the outside of the chamber having an atmospheric pressure atmosphere. In this case, even if a region in which the transfer layer 179 and the organic insulating layer 150 are not completely contacted is generated, the interior of the two components is in a vacuum state, so that the pressure difference is exposed to atmospheric pressure. As a result, the organic light emitting layer 150 and the transfer layer 179 are in complete contact with each other.

Next, as shown in FIG. 3G, the transfer layer (179 of FIG. 3F) of the transparent conductive material transferred to the substrate 101 on which the organic light emitting layer 150 is formed forms the second electrode 155. In this case, the second electrode 155 serves as an anode electrode.

Since the second electrode 155 of the transparent conductive material formed on the organic light emitting layer 150 is not formed by deposition through sputtering using plasma, internal damage of the organic light emitting layer 150 due to the plasma atmosphere does not occur at all. It is characterized by not. Therefore, since there is no damage inside the organic light emitting layer, dark spots are not generated, thereby improving display quality.

On the other hand, the substrate 101 on which the second electrode 155 formed by the above-described transfer method is formed is not shown in the figure, but a seal pattern (not shown) is formed along the edge thereof, and inside the seal pattern (not shown). After patterning the moisture absorbent (not shown), the organic light emitting device 100 according to the first embodiment of the present invention can be completed by bonding the transparent substrate (not shown) in a vacuum atmosphere or an inert gas atmosphere.

In this case, the transfer substrate used for manufacturing the organic light emitting device according to the first embodiment of the present invention described above may be manufactured by a simple method. That is, as an example of the transparent substrate, an absorption layer is formed by depositing one metal material selected from molybdenum (Mo), silver (Ag), and aluminum (Al) through sputtering. Thereafter, a sacrificial layer is formed by applying an organic material having a property of reducing adhesion when heat is applied to the absorber layer, and a transparent conductive material such as indium-tin-oxide (ITO) or indium- is sputtered onto the sacrificial layer. It can be completed by depositing zinc oxide (IZO) to form a transfer layer. In this case, the sacrificial layer is characterized in that the adhesive force at the interface with the other layer is weakened when the heat is applied, wherein the adhesive force with the transfer layer is weakened at a faster rate than the adhesive force with the absorbing layer. Therefore, only the transfer layer is transferred to another substrate by the characteristics of the sacrificial layer.

4 is a schematic cross-sectional view of an organic light emitting diode according to a second exemplary embodiment of the present invention with respect to one pixel area. In the case of the second embodiment, the driving and switching thin film transistor has an example bottom gate structure having a semiconductor layer 212 including an active layer 212a and an ohmic contact layer 212b.

 As illustrated, the organic light emitting diode 200 according to the second exemplary embodiment of the present invention crosses each other and includes a gate line (not shown), a data line 220, and a driving and switching thin film that defines the pixel area P. Interposed between the first substrate 201 having a transistor DTr (not shown), the first and second electrodes 253 and 260 corresponding to the first substrate 201, and the two electrodes 253 and 260. A second substrate 250 including an organic light emitting diode E formed of the organic light emitting layer 258, and more precisely, each pixel region of the first and second substrates 201 and 250. A connection electrode electrically connecting the drain electrode 227 of the driving thin film transistor DTr provided for each (P) and the second electrode 260 provided for each pixel region P under the second substrate 250. 245 and seal patterns (not shown) formed at the edge portions of the first and second substrates 201 and 250. At this time, a moisture absorption pattern (not shown) made of a moisture absorption material is further configured inside the seal pattern.

In the organic light emitting device 200 according to the second embodiment of the present invention having the above-described structure, the array element of the switching and driving thin film transistor (DTr) and the organic light emitting diode E are different from each other. Since it is formed on the substrates 201 and 250 and bonded to each other, it can be seen that an array structure manufacturing yield and an organic light emitting diode manufacturing yield are separately managed, which is advantageous in terms of product yield.

Meanwhile, in the first embodiment of the present invention, a second electrode formed in contact with the organic light emitting layer and formed later than the organic light emitting layer is formed on the entire surface of the substrate, and a first electrode formed before the organic light emitting layer is patterned for each pixel region. In the second exemplary embodiment of the present invention, the second electrode 260, which is in contact with the organic light emitting layer 258 and formed later than the organic light emitting layer 258, is formed for each pixel region P. FIG. The first electrode 253 having a separated shape and formed before the organic light emitting layer 258 is formed on the front surface.

Meanwhile, a method of manufacturing the organic light emitting diode according to the second embodiment of the present invention having the above-described structure will be described. At this time, the characteristic manufacturing method of the present invention is mainly focused on the method of manufacturing the second substrate having the organic light emitting diode because the formation of the second electrode formed in contact with the organic light emitting layer.

 In the case of the first substrate 201 including the driving and switching thin film transistors DTr (not shown), the gate and data lines (not shown) 220 and the driving and switching thin film transistors DTr (not shown) are manufactured by a general manufacturing method. The protection layer 230 including the contact hole 235 is formed on the driving and switching thin film transistor DTr (not shown), and each pixel area P is formed on the protection layer 230. After forming the column-shaped spacer 240 for each column, the connection electrode 245 covering the spacer 240 and contacting the drain electrode 227 of the driving thin film transistor DTr through the contact hole 235. Can be completed.

5A through 5F are cross-sectional views illustrating manufacturing processes of one pixel area of an organic light emitting diode substrate for an organic light emitting diode according to a second exemplary embodiment of the present invention.

First, as illustrated in FIG. 5A, a first material (eg, aluminum (Al) or aluminum alloy (AlNd)) having a relatively low work function value is deposited on the front surface of the second substrate 250 by sputtering. 253).

Next, as illustrated in FIG. 5B, an organic insulating material is coated on the first electrode 253, and then patterned by patterning the organic insulating material to correspond to the gate and data wirings of the first substrate. The partition 256 is formed to trap the shape. In this case, a buffer pattern (not shown) has a width wider than that of the barrier rib 256 in the portion where the barrier rib 256 is to be formed before the barrier rib 256 is formed and captures each pixel region P using an inorganic insulating material. May be further formed.

  Next, as shown in FIG. 5C, the organic light emitting material is applied to the second substrate 250 on which the partition wall 256 is formed by red, green, and blue for each pixel region P through nozzle coating or inkjet coating. An organic emission layer 258 that emits light is formed. In this case, the height of the organic light emitting layer 258 is equal to or smaller than the height of the partition wall 256. In the case of the second embodiment of the present invention, unlike the first embodiment, there is no restriction on the height difference between the organic light emitting layer 258 and the partition 256.

Meanwhile, although the organic light emitting layer 258 is illustrated as having a single layer structure in the drawing, the organic light emitting layer 258 may be formed to have a multilayer structure in order to increase the light emitting efficiency. Since this is the same as in the first embodiment described above, description thereof will be omitted.

Next, as illustrated in FIG. 5D, a second substrate 250 having the organic light emitting layer 258 formed inside the vacuum chamber 290 capable of forming a vacuum atmosphere, and a transparent substrate 270 corresponding thereto. Absorbing layer 273 capable of converting light energy into thermal energy by laser beam irradiation on a glass substrate and a sacrificial layer 276 made of an organic material and a transparent conductive material having a high work function value, for example, indium-tin-oxide (ITO) Or a transfer layer 279 formed of indium-zinc-oxide (IZO) and patterned to correspond to each of the plurality of pixel regions P. ) And the organic light emitting layer 258 face each other.

Next, as illustrated in FIG. 5E, the organic light emitting layer 258 and the organic light emitting layer 258 facing each other and the transfer substrate 270 facing each other in a vacuum atmosphere in the vacuum chamber 290 may be formed. The laser beam LB having a specific wavelength band and energy density is transferred to the transfer substrate 270 using the laser irradiation apparatus 293 in a state in which the transfer layer 279 is spaced apart from each other by several hundred μm to several mm. Investigate as if scanning from one end to the other.

The absorption layer 273 corresponding to the portion irradiated with the laser beam LM having the specific wavelength band and energy density by the laser beam LB irradiation converts the energy of the irradiated laser beam LM into thermal energy. It will dissipate heat. In this case, heat emitted from the absorbing layer 273 is transferred to the sacrificial layer 276 made of the organic material, and the sacrificial layer 276 has weakened adhesive force on the surface thereof, and thus each of the plurality of patterned transfer layers is patterned. 279 is gradually separated from the sacrificial layer 276. In this case, the transfer layer 279 separated from the sacrificial layer 276 is in contact with the organic light emitting layer 258 formed for each pixel region P and transferred to the organic light emitting diode substrate 250, thereby to FIG. 5F. As illustrated, the second electrode 260 separated for each pixel region P is formed. In this case, all of these processes are performed in a vacuum atmosphere inside the vacuum chamber 290 of FIG. 5E, and there is no room for an air layer to be interposed between the second electrode 260 and the organic light emitting layer 258 that are transferred and formed. In this case, the first electrode 253 formed on the entire surface of the substrate 250, the organic emission layer 258, and the second electrode 260 formed for each pixel region P form an organic electroluminescent diode (E).

Also in the fabrication of the organic light emitting diode substrate according to the manufacturing method of the second embodiment of the present invention, the transfer by laser irradiation without forming the second electrode 260 formed in contact with the organic light emitting layer 258 by sputtering By forming by the method, dark spots due to damage to the organic light emitting layer 258 can be prevented.

Next, referring to FIG. 4, the edge of the second substrate 250 having the organic light emitting diode manufactured as described above, the first substrate 201 having the thin film transistor DTr and the connecting electrode 245 formed thereon The organic electroluminescent device 200 according to the second embodiment of the present invention may be completed by forming a seal pattern (not shown) and bonding them in a vacuum atmosphere or an inert gas atmosphere.

On the other hand, the transfer substrate used for manufacturing the organic light emitting device according to the second embodiment of the present invention is connected to the front surface as a transparent conductive material on the front surface of the sacrificial layer by the method of manufacturing the transfer substrate shown in the first embodiment. After forming the transfer layer in a state, it can be manufactured by forming a plurality of transfer layers separated by the size of each pixel area by performing a mask process and patterning it.

1 is a schematic circuit diagram of one pixel area of a general active matrix organic light emitting diode.

2 is a schematic cross-sectional view of a conventional organic light emitting device.

3A to 3G are cross-sectional views illustrating manufacturing steps of one pixel area including a driving thin film transistor and an organic light emitting diode of an organic light emitting diode according to a first embodiment of the present invention.

4 is a cross-sectional view schematically showing an organic light emitting display device according to a second exemplary embodiment of the present invention with respect to one pixel area.

5A through 5F are cross-sectional views illustrating manufacturing steps of one pixel area of an organic light emitting diode substrate for an organic light emitting diode according to a second exemplary embodiment of the present invention.

<Explanation of symbols for main parts of the drawings>

101 substrate 105 semiconductor layer

105a: active layer 105b: impurity doped region

108: gate insulating film 113: gate electrode

117: interlayer insulating film 120: data wiring

125 source electrode 128 drain electrode

133: protective layer 135: contact hole

140: first electrode 145: partition wall

150: organic light emitting layer 170: transfer substrate (glass substrate)

173: absorber layer 176: sacrificial layer

179: transfer layer 190: vacuum chamber

193: laser irradiation device LB: laser beam

P: pixel area

Claims (8)

 Preparing a transfer substrate having a sequentially stacked absorber layer, a sacrificial layer, and a transfer layer; Forming a gate wiring and a data wiring crossing the substrate to define a pixel region, a switching thin film transistor connected to the gate and the data wiring in each pixel region, and a driving thin film transistor connected to one electrode of the switching thin film transistor. Steps; Forming a first electrode in each pixel region in contact with one electrode of the driving thin film transistor; Forming barrier ribs overlapping edges of the first electrode on the boundary of each pixel region; Forming an organic emission layer over each of the first electrodes in each pixel region; Positioning the substrate and the transfer substrate such that the organic light emitting layer and the transfer layer are spaced apart and face each other; Irradiating a laser beam from one side to the other side in a vacuum atmosphere to transfer the transfer layer to a substrate on which the organic light emitting layer is formed, thereby forming a second electrode contacting the barrier rib and the organic light emitting layer. The method of claim 1, wherein the absorbing layer serves to convert light energy into thermal energy, and the sacrificial layer has a property of weakening adhesion to the transfer layer when heated. The method of claim 1, The height difference between the surface of the organic light emitting layer and the top end of the partition wall is a few hundred Å to 1㎛ characterized in that the organic light emitting device manufacturing method. The method of claim 1, Preparing the transfer substrate, Forming the absorbing layer by depositing a metal material selected from molybdenum (Mo), silver (Ag), and aluminum (Al) on the transparent substrate; Forming the sacrificial layer by applying an organic material on the absorber layer; Forming the transfer layer by depositing indium-tin-oxide (ITO) or indium-zinc-oxide (IZO) over the sacrificial layer Method for manufacturing an organic light emitting device comprising a. The method of claim 1, And forming a protective layer having a contact hole exposing one electrode of the driving thin film transistor on the entire surface of the driving thin film transistor before forming the first electrode. Preparing a transfer substrate having a sequentially stacked absorbing layer, a sacrificial layer, and a patterned transfer layer; A gate line and a data line intersecting each other on the first substrate to define a pixel area, a switching thin film transistor connected to the gate and data line in each pixel area, and a driving thin film transistor connected to one electrode of the switching thin film transistor. Forming; Forming a first electrode on an entire surface of an inner surface of a second substrate corresponding to the first substrate; Forming barrier ribs on the boundary of each pixel area over the first electrode; Forming an organic light emitting layer on the first electrode in each pixel region surrounded by the partition wall; Positioning the second substrate and the transfer substrate such that the organic light emitting layer and the patterned transfer layer are spaced apart and face each other; Irradiating a laser beam from one side to the other side in a vacuum atmosphere to transfer the patterned transfer layer to a substrate on which the organic light emitting layer is formed to form a second electrode contacting the organic light emitting layer for each pixel region. Steps; Bonding the first substrate to the second substrate such that one electrode and the second electrode of the driving thin film transistor are electrically connected to each other; The method of claim 1, wherein the absorbing layer serves to convert light energy into thermal energy, and the sacrificial layer has a property of weakening adhesion to the patterned transfer layer when subjected to heat. The method of claim 5, wherein Preparing the transfer substrate, Forming the absorbing layer by depositing a metal material selected from molybdenum (Mo), silver (Ag), and aluminum (Al) on the transparent substrate; Forming the sacrificial layer by applying an organic material on the absorber layer; Depositing and patterning indium tin oxide (ITO) or indium zinc oxide (IZO) over the sacrificial layer to form the patterned transfer layer Method for manufacturing an organic light emitting device comprising a. The method of claim 5, wherein Forming a protective layer on the front surface of the driving thin film transistor, the protective layer having a contact hole exposing one electrode of the driving thin film transistor; Forming a columnar spacer in each pixel area over the passivation layer; Forming a connection electrode in each pixel region while completely covering the spacer and contacting one electrode of the driving thin film transistor through the contact hole. And an electrical connection between one electrode of the driving thin film transistor and the second electrode is made by contacting the connection electrode and the second electrode formed covering the spacer. The method according to claim 1 or 5, Forming the organic light emitting layer, Organic electroluminescence comprising sequentially laminating an electron injection layer, an electron transporting layer, an organic light emitting material layer, a hole transporting layer and a hole injection layer Method of manufacturing the device.

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