KR100685410B1 - OLED and fabricating method of the same - Google Patents

Abstract

An organic light emitting display device and a method of manufacturing the same. A substrate having a light emitting area and a non-light emitting area; A pixel electrode on the emission area of the substrate; A spacer on the non-emission area around the pixel electrode, the spacer having a predetermined distance from the emission area; And an organic layer including an emission layer on the pixel electrode, and a method of manufacturing the same.

Spacer, Laser Thermal Transfer, Organic Light Emitting Display

Description

Organic light emitting display device and manufacturing method thereof {OLED and fabricating method of the same}

1A to 1C are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a first embodiment of the present invention;

2A to 2C are plan views illustrating formation of spacers on a substrate;

3A to 3B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a second embodiment of the present invention;

4A and 4B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a third embodiment of the present invention.

Explanation of reference numerals for the main parts of the drawing

100, 200: substrate, 120, 220: thin film transistor,

140 and 240 pixel electrodes 160 and 260 spacers

150, 250: pixel defining layer, 170R, 170G, 170B: emitting layer,

L: light emitting region, A, B, C: unit pixel region,

30, 40: donor substrate, 35, 45: transfer layer,

5: laser beam

The present invention relates to an organic light emitting display device and a manufacturing method thereof, and more particularly, to a method of manufacturing an organic light emitting display device to improve the edge pattern characteristics of the patterned light emitting layer.

Among the flat panel display devices, the organic light emitting display device has a high response time with a response speed of 1 ms or less, low power consumption, and no self-emission, so there is no problem in viewing angle. . In addition, low-temperature manufacturing is possible, and the manufacturing process is simple based on the existing semiconductor process technology has attracted attention as a next-generation flat panel display device in the future.

In the inkjet printing method of the light emitting layer patterning method of the organic light emitting display device, the material of the organic layers other than the light emitting layer is limited, and it is troublesome to form a structure for inkjet printing on the substrate. In addition, when the light emitting layer is patterned by the deposition process, it is difficult to manufacture a large device due to the use of a metal mask.

Recently, the laser induced thermal imaging (LITI) has been developed as a technique to replace the above patterning method.

The laser thermal transfer method converts a laser beam from a light source into thermal energy, and transfers a pattern forming material to a target substrate using the thermal energy to form a pattern. For this method, a donor substrate, a light source, and a subject having a transfer layer are formed. Phosphorus substrate is required.

In the laser thermal transfer method, a donor substrate is positioned on the substrate, and a patterning is performed by irradiating a laser beam after performing a lamination process. If the donor substrate is not in close contact with the substrate, patterning is not performed, or the width of a pattern This smaller defect may occur. On the contrary, if the donor substrate is in close contact with the substrate, it may be difficult to partially transfer to a peripheral portion other than the area irradiated with the laser, thereby obtaining an accurate pattern. That is, it is difficult to determine the proper adhesion level between the donor substrate and the substrate by adjusting the pressure of lamination.

US Patent Publication No. 20030162108 discloses an array of organic light emitting display devices having a spacer by Mitchell S. Burberry et al. Entitled "Using spacer elements to make electroluminescent display devices." The above invention relates to improving laser thermal transfer characteristics by adjusting the height of the donor substrate and the substrate by forming a spacer on the substrate. However, since the exact position and spacing of the spacers on the substrate have not been taken into account, the edge region may not be accurate when patterning.

An object of the present invention is to provide a method of manufacturing an organic light emitting display device which improves patterning characteristics of a light emitting layer by forming spacers to have a predetermined distance from the light emitting regions of the unit pixel regions.

According to an aspect of the present invention, there is provided a substrate including a light emitting region and a non-light emitting region; A pixel electrode on the emission area of the substrate; A spacer on the non-emission area around the pixel electrode, the spacer having a predetermined distance from the emission area; And an organic layer including a light emitting layer on the pixel electrode.

In addition, to achieve the above technical problem, the present invention comprises the steps of forming a pixel electrode on the light emitting area of the substrate having a light emitting area and a non-light emitting area; Forming spacers on the non-emission area around the pixel electrode to have a predetermined distance from the emission area; And forming a light emitting layer on the pixel electrode.

The spacer may be formed to have a gap between the light emitting regions of the unit pixels and a size smaller than the substrate size by 2 μm or more.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. The following embodiments are provided as examples to sufficiently convey the spirit of the present invention to those skilled in the art. Accordingly, the invention is not limited to the embodiments described below and may be embodied in other forms. In the drawings, lengths, thicknesses, and the like of layers and regions may be exaggerated for convenience. Like numbers refer to like elements throughout.

1C is a cross-sectional view of an organic light emitting display device according to a first embodiment of the present invention.

Referring to the drawings, the pixel electrode 140 is positioned on the light emitting area of the substrate 100 having the light emitting area and the non-light emitting area. On the non-emission area around the pixel electrode 140, a spacer 160 having a predetermined distance from the emission area is positioned. In addition, an organic layer including emission layers 170R, 170G, and 170B is disposed on the pixel electrode 140. Located.

1A to 1C are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a first embodiment of the present invention.

Referring to the drawing, the thin film transistor 120 is formed on the substrate 100 having the unit pixel regions A, B, and C. Referring to FIG. The thin film transistor 120 is formed by forming a semiconductor layer, a gate electrode, and a source electrode and a drain electrode respectively connected to the semiconductor layer.

In order to prevent impurities from flowing into the semiconductor layer from the substrate 100, the buffer layer 110 may be formed on the substrate before the thin film transistor 120 is formed.

An insulating layer 130 is formed on the thin film transistor 120.

The insulating layer 130 may be formed of an inorganic layer, an organic layer, or a double layer thereof. For example, the planarization layer 135 is formed on the patterned electrodes and the interconnections. The planarization layer 135 may be an organic layer.

Before forming the planarization layer 135, it is preferable to form an inorganic protective layer 135, which is an insulating layer, for the protection of the lower layer and the passivation of the semiconductor layer of the thin film transistors.

A via hole exposing the drain electrode of the thin film transistor 120 is formed in the insulating layer 130. A conductive film is stacked and patterned on the insulating layer 130 to form a pixel electrode 140 contacting the drain electrode through the via hole.

An insulating layer is stacked and patterned on the pixel electrode 140 to form a pixel defining layer 150 that partially exposes the pixel electrode 140. This defines the light emitting area.

Spacers 160 are formed on the pixel defining layer 150 to have a predetermined distance l from the emission region L of the unit pixel regions A, B, and C.

The spacer 160 may be formed to have a predetermined distance from the light emitting region L at a distance of 2 μm or more in the light emitting region L of the unit pixels A, B, and C. FIG. Can be. When the interval is less than or equal to 2 μm, a region that is not patterned may penetrate into the light emitting region. Therefore, it is preferable that the spacer 160 has a spacing of 2 μm or more from the light emitting area. In addition, since at least two spacers must be present, the spacing must be smaller than the substrate size in order to form two or more spacers.

In addition, the spacer may be formed in one shape selected from the group consisting of a spherical shape, a rod shape, and a line shape.

2A to 2C are plan views illustrating the formation of spacers on a substrate, as seen from above.

Referring to the drawings, FIGS. 2A and 2B show the formation of a linear spacer, and FIG. 2C shows the formation of a spherical spacer. That is, the spacer 160 may be formed in a line shape so as to have a predetermined interval l parallel to the unit pixels A, B, and C (FIG. 2A), or the unit pixels A, B Can be formed in a line shape perpendicular to (C) (FIG. 2B). In addition, the unit pixels A, B, and C may be formed in a spherical shape or a bar shape so as to have a predetermined distance l from the light emitting area L of the unit pixels A, B, and C (FIG. 2C).

Referring back to FIG. 1A, the spacer 160 may be formed to have a height of 0.5 to 5 μm. If the spacer 160 is too low, the effect due to the spacer may not appear, and if the spacer 160 is too high, patterning may not be performed in the light emitting area. Therefore, the spacer 160 may have a height of 0.5 to 5 μm.

The spacers 160 may be formed using photoresist. That is, the spacers 160 are formed on the pixel defining layer 150 at a predetermined interval l by forming a photoresist film on the substrate and performing exposure and patterning.

In addition, the spacers 160 may be formed using inkjet printing. That is, the spacers 160 may be formed by printing the pixel defining layer 150 at a predetermined interval l.

An emission layer is formed on the exposed pixel electrode 140.

The light emitting layer may be formed by a laser thermal transfer method. That is, the donor substrate 30 on which the transfer layer 35 is formed is positioned on the substrate on which the spacer 160 is formed. The donor substrate 30 has a photothermal conversion layer 33 positioned between the transfer layer 35 and the base substrate.

The photothermal conversion layer 33 is formed of a light absorbing material having a property of absorbing light in the infrared-visible light region. One of an organic film, a metal, and a composite layer thereof containing a laser light absorbing material. The photothermal conversion layer 33 serves to convert the laser beam irradiated from the laser into thermal energy, and the thermal energy is changed by changing the adhesive force between the transfer layer 35 and the photothermal conversion layer 33. It serves to transfer 35 onto the substrate as a subject.

Referring to FIG. 1B, the donor substrate 30 is laminated to be in close contact with the substrate. The lamination is accomplished by pressurization using rollers, gas pressurization, or crown presses. The transfer layer 35 is patterned by irradiating a laser beam 5 on the donor substrate. The transfer layer 35 may be a light emitting layer.

The adhesion degree between the donor substrate and the substrate may be controlled by the spacer 160 formed on the pixel defining layer 150, thereby obtaining a clean pattern.

In addition, by forming the spacer 160 at a predetermined interval from the light emitting region, the spacer 160 may have a constant adhesive strength from the periphery of the light emitting region, thereby forming a light emitting layer 170R having a cleaner pattern.

Referring to FIG. 1C, each of the light emitting layers 170G and 170B is formed on each of the unit pixel areas A, B, and C, and on the patterned light emitting layers 170R, 170G, and 170B. The counter electrode is formed.

A charge injection layer or a charge transport layer may be formed on or below the light emitting layers 170R, 170G, and 170B.

3A and 3B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a second embodiment of the present invention. Unlike the first embodiment, the second embodiment of the present invention is to form the spacers using a donor substrate.

The donor substrate may be formed by depositing a spacer material on the non-transfer region of the donor substrate and simultaneously depositing the spacer material on the transfer layer patterning. Furthermore, a spacer and a transfer layer may be formed sequentially by forming a spacer using the said donor substrate for vapor deposition and forming a transfer layer using the donor substrate for transfer layer formation.

Referring to FIG. 3A, the pixel electrode 240 and the pixel defining layer 250 are formed on the substrate 200 as in the first embodiment. Then, the spacer 260 is formed on the donor substrate 40. The spacer 260 may be formed above or below the transfer layer 45 of the donor substrate, and may be formed in the non-transfer region of the donor substrate.

The spacer 260 is aligned with the substrate 200 such that the spacer 260 is positioned between the light emitting regions L of the substrate 200. That is, the donor substrate 40 is positioned on the substrate 20 such that the spacer 260 is positioned on the pixel defining layer 250 of the substrate 200. In addition, the spacer 260 is formed to have a predetermined distance (l) from the light emitting region (L). Like the first embodiment, the spacer 260 may be formed as shown in FIGS. 2A to 2C.

The spacer 160 may be formed to have a predetermined distance from the light emitting region L at a distance of 2 μm or more in the light emitting region L of the unit pixels A, B, and C. FIG. Can be. That is, as described in the first embodiment, when the interval is 2 μm or less, since the non-patterned region can penetrate into the interior of the emission area, it is preferable to have the interval between the emission area and 2 μm or more. .

In addition, if the spacer 260 is too low, the effect due to the spacer may not appear, and if the spacer 260 is too high, patterning may not be performed in the light emitting area. Therefore, the spacer 260 may have a height t of 0.5 to 5 μm. .

Referring to FIG. 3B, a donor substrate on which the spacer is formed is laminated with the substrate. The lamination is accomplished by pressurization using rollers, gas pressurization, or crown presses. The transfer layer 45 is patterned by irradiating a laser beam 5 on the donor substrate. The transfer layer 45 may be a light emitting layer.

Since the adhesion degree between the donor substrate and the substrate may be controlled by the spacers 260 formed at predetermined intervals on the pixel defining layer 250, a light emitting layer having a clean pattern may be obtained.

4A and 4B are cross-sectional views illustrating a method of manufacturing an organic light emitting display device according to a third embodiment of the present invention.

Referring to the drawings, the third embodiment of the present invention uses a donor substrate like the second embodiment, but unlike the second embodiment, a portion of the transfer layer is first detached from the donor substrate to serve as a spacer. .

In other words, forming a spacer using a donor substrate may be performed by closely contacting the transfer layer of the donor substrate to the pixel defining layer in advance so as to have a predetermined interval before forming the light emitting layer, and closely contacting the pixel defining layer. The transfer layer of the portion may be formed by detaching from the donor substrate.

Referring to FIG. 4A, the pixel electrode 240 and the pixel defining layer 250 are formed on the substrate 200. The donor substrate 40 on which the transfer layer 45 is formed is positioned on the substrate 200.

The substrate 200 and the donor substrate 40 are laminated, and the laser beam 5 is irradiated so that points or lines are orthogonal to the pattern at regular intervals between the unit pixels B and C. That is, the laser beam is irradiated onto the donor substrate 40 in the form as shown in FIGS. 2A to 2C. Therefore, as the transfer layer of the portion irradiated with the laser swells, the substrate 200 and the donor substrate 40 are lifted up to serve as spacers.

 In addition, the excited portion of the transfer layer is preferably formed to have a predetermined distance (l) and the light emitting region (L). Further, the light emitting region L may be formed to have a predetermined spacing ㅣ at intervals of 2 μm or more in the light emitting region L of the unit pixels A, B, and C. That is, as in the above examples, when the interval is less than or equal to 2 μm, the non-patterned area may penetrate into the interior of the emission area. Therefore, it is preferable to have an interval between the emission area and 2 μm or more. In addition, since at least two spacers must be present, the spacing must be smaller than the substrate size in order to form two or more spacers.

Referring to FIG. 4B, after forming the transfer layer serving as the spacer, the transfer layer 45 is patterned on the emission area by irradiating a laser beam 5 on the donor substrate. The transfer layer 45 may be a light emitting layer.

The excited portions of the transfer layer formed on the pixel defining layer 250 at regular intervals serve as spacers. Therefore, the degree of adhesion between the donor substrate and the substrate may be adjusted due to the excited portion of the transfer layer formed on the pixel defining layer 250, thereby obtaining a clean light emitting layer pattern.

As in FIG. 1C, the organic light emitting display device is completed by forming each light emitting layer on each unit pixel region A, B, and C in the same manner as described above, and forming an opposite electrode on the patterned light emitting layer. . A charge injection layer or a charge transport layer may be formed on or below the light emitting layer.

In the method of manufacturing an organic light emitting display device according to the present invention, by forming a structure serving as a spacer and a spacer around the light emitting region, the adhesion between the donor substrate and the substrate is controlled by the spacer to obtain a clean light emitting layer pattern. It has an effect.

 In addition, since the spacers are formed to have a predetermined distance from the light emitting regions of the unit pixel regions, the spacers may have a constant adhesive strength from the periphery of the light emitting region, thereby forming a light emitting layer having a cleaner pattern without biasing in either direction. Can be.

Although described above with reference to a preferred embodiment of the present invention, those skilled in the art will be variously modified and changed within the scope of the invention without departing from the spirit and scope of the invention described in the claims below I can understand that you can.

Claims (15)

A substrate having a light emitting area and a non-light emitting area; A pixel electrode on the emission area of the substrate; A spacer on the non-emission area around the pixel electrode, the spacer having a predetermined distance from the emission area; And An organic light emitting display device having an organic layer including a light emitting layer on the pixel electrode. The method of claim 1, The spacer has an organic light emitting display device having a gap between the light emitting regions of the unit pixels and a size smaller than the substrate size by 2 μm or more. The method of claim 1, The spacer is an organic light emitting display device having a shape selected from the group consisting of a sphere, a rod, and a line. The method of claim 1, The spacer is an organic light emitting display device having a height of 0.5 to 5㎛. Forming a pixel electrode on the light emitting area of the substrate having a light emitting area and a non-light emitting area; Forming spacers on the non-emission area around the pixel electrode to have a predetermined distance from the emission area; And A method of manufacturing an organic light emitting display device comprising forming a light emitting layer on the pixel electrode. The method of claim 5, And the spacers are formed to have a gap between the light emitting regions of the unit pixels and a size smaller than the substrate size by 2 μm or more. The method of claim 5, The method of manufacturing an organic light emitting display device is to form the spacer in one form selected from the group consisting of a spherical shape, a rod shape, and a line shape. The method of claim 5, Forming the spacer is a method of manufacturing an organic light emitting display device having a height of 0.5 to 5㎛. The method of claim 5, And forming the spacers using photoresist. The method of claim 5, And forming the spacers by using inkjet printing. The method of claim 5, Forming the spacers is a method of manufacturing an organic light emitting display device using a donor substrate. The method of claim 11, The forming of the spacer using the donor substrate may include depositing a spacer material on a non-transfer region of the donor substrate and simultaneously depositing a spacer material upon transfer layer patterning. The method of claim 11,  Forming a spacer using the donor substrate is to form a spacer using a donor substrate for spacer deposition and a transfer layer using a donor substrate for transfer layer formation, thereby sequentially forming a spacer and a transfer layer. A method of manufacturing an organic light emitting display device. The method of claim 11, Forming a spacer by using the donor substrate, before the light emitting layer is formed, the transfer layer of the donor substrate is partially adhered to the non-light emitting region at predetermined intervals, and the transfer layer of the adhered portion is The organic light emitting display device of claim 1, wherein the organic light emitting display device is formed by being detached from the donor substrate. The method of claim 5, The method of manufacturing an organic light emitting display device is such that the light emitting layer is formed by a laser thermal transfer method.

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