KR100774949B1 - Light Emitting Diode and Method for Manufacturing the same - Google Patents

Abstract

An electroluminescent device and a method of manufacturing the same.

In the electroluminescent device according to the present invention, a barrier rib is formed between an anode electrode and a cathode electrode electrically connected to a driving element formed on a substrate, and an emission region and an emission region in which upper and lower emission layers are formed on both sides of the barrier rib, respectively. And a plurality of contact holes for connecting the cathode electrodes of the light emitting region to the first and second electrodes and the first and second electrodes which are formed adjacent to the ground and grounded to the ground.

Electroluminescent element, double sided light emitting, contact hole

Description

Light Emitting Diode and Method for Manufacturing the Same

1 is a view showing the structure of a conventional double-sided light emitting organic electroluminescent device.

2 is a view showing the structure of another conventional double-sided light emitting organic electroluminescent device.

3A is a cross-sectional view of an electroluminescent device according to a first embodiment of the present invention, and FIG. 3B is a plan view showing the electroluminescent device of FIG. 3A on a plane.

4A to 4I are steps illustrating a step of manufacturing a double-sided light emitting device according to the manufacturing method of the present invention.

5 is a view showing an electroluminescent device formed by the manufacturing method of the present invention.

<Explanation of symbols on main parts of the drawings>

301: transparent substrate 304: gate electrode

307: passivation film or flat film 308: anode for bottom emission

309: anode for emitting light 311: partition wall

312a: upper emission layer 312b: lower emission layer

313 and 315 cathode electrode 322 contact hole

331: first electrode 332: second electrode

350: light emitting area

The present invention relates to an electroluminescent device and a method of manufacturing the same.

In the organic light emitting display device, electrons and holes are injected into the light emitting layer from an electron injection electrode and a hole injection electrode, respectively, and an exciton in which the injected electrons and holes combine is excited. The device emits light when it falls from the ground state to the ground state.

The organic light emitting diode is classified into a passive matrix organic light emitting diode (PMOLED) and an active matrix organic light emitting diode (AMOLED) according to a driving method.

In general, an active matrix type organic light emitting display device has an advantage of providing high luminous efficiency and high image quality, and uses a thin film transistor (TFT) as a switching device for driving pixels independently.

Such an organic light emitting display device has a top emission type, a bottom emission type, and a dual emission type according to a direction in which light is emitted.

Here, there are many problems to be studied in the double-sided organic light emitting diode capable of realizing images on both sides. Hereinafter, a problem with the related art of the double-sided organic light emitting diode will be described.

1 is a view showing the structure of a conventional double-sided light emitting organic electroluminescent device.

The polysilicon layer 102 is formed on the glass substrate 101, the gate electrode 104 is formed on the glass substrate 101, and the source / drain region 103 is formed by heat treatment using the gate electrode 104 as a mask. Let's do it. The gate electrode 104 is insulated by the gate insulating film 105. A source / drain electrode 106 is formed in the hole formed in the gate insulating film 105. A passivation film or a flat film 107 is formed thereon.

A hole is formed in the passivation film or the flat film 107, and the first electrode 108 is electrically connected to the source / drain electrode 106 through the hole. The insulating layer 109 is patterned on the upper portion of the thin film transistor, and the organic light emitting layer 110 and the second electrode 111 are sequentially formed thereon.

Here, the glass cap 113 is attached to the device using the sealant 115 to encapsulate it. At this time, the inside (gether) 114 may be attached.

Currently, the display adopted in the mobile phone is divided into a sub panel and a main panel, and after making two lower emitting organic electroluminescent devices as shown in FIG. ) Into the phone.

In such a case, the two devices are manufactured and attached to the mobile phone by attaching the light emitting surfaces to be opposite to each other, and the thickness of the module becomes thick.

2 is a view showing the structure of another conventional double-sided light emitting organic electroluminescent device.

That is, the polysilicon layer 202 is formed on the glass substrate 201, the gate electrode 204 is formed on the glass substrate 201, and then the heat treatment is performed by using the gate electrode 204 as a mask. To form. The gate electrode 204 is insulated by the gate insulating film 205. A source / drain electrode 206 is formed in the hole formed in the gate insulating film 205. The passivation film or the flat film 207 is formed in the upper part.

A hole is formed in the passivation film or the flat film 207, and the first electrode 208 is electrically connected to the source / drain electrode 206 through the hole. The insulating film 209 is patterned on the upper portion of the thin film transistor, and the organic light emitting layer 210 and the second electrode 211 are sequentially formed on the thin film transistor.

Two devices having such a structure are manufactured, respectively, and attached by using the sealant 215 so that the light emitting surfaces are opposite to each other, thereby completing a double-sided light emitting device.

However, the double-sided light emitting device shown in FIG. 2 also has the limitation of making two devices, as in the case of FIG. 1, except that the step of using encapsulation glass is omitted.

Therefore, a shorter process, a lower cost, and a thinner double-sided light emitting organic light emitting display device are in need of structural research and development.

SUMMARY OF THE INVENTION An object of the present invention for solving the above problems is to provide a double-emitting light emitting device capable of depositing an upper emitting layer and a lower emitting layer on one pixel, and selectively emitting the formed emitting layer on both sides or selectively by one side. will be.

In addition, by forming an upper emission layer and a lower emission layer on each pixel, a double-sided light emitting device can be implemented without any additional process, thereby dramatically reducing component cost and device thickness.

In the electroluminescent device according to the present invention for solving the above problems, a partition wall is formed between the anode electrode and the cathode electrode electrically connected to the drive element formed on the substrate, the upper light emitting layer and the lower light emitting layer on both sides around the partition wall Each formed light emitting region; First and second electrodes formed in parallel with the light emitting area and grounded to the ground; And a plurality of contact holes for connecting the cathode electrodes of the emission region to the first and second electrodes.

Here, the anode electrode is characterized in that connected to any one of the source / drain electrode of the driving element.

delete

The cathode electrode formed on the upper light emitting layer is a transparent metal, and the cathode electrode formed on the lower light emitting layer is opaque metal.

The organic light emitting layer is formed on the light emitting layer formed in the light emitting region.

The upper light emitting layer and the lower light emitting layer are selected by double-sided light emission or one surface by light emission by the cathode electrodes formed on the first and second electrodes.

On the other hand, the manufacturing method of the electroluminescent device according to the present invention comprises the steps of forming a drive element on the transparent substrate, the passivation film or a flat film on the drain electrode of the drive element; Forming a contact hole in a passivation film or a flat film to form a lower light emitting anode electrode in one of the regions other than the upper part of the driving device so as to be electrically connected to the drain electrode; Forming an upper light emitting anode electrode on the other side of the region other than the upper portion of the driving device to be electrically connected to the lower light emitting electrode; Forming an insulating film on the driving device, and forming a partition on the insulating film; Forming a light emitting layer such that an upper light emitting layer and a lower light emitting layer are separated using a partition wall; Insulating the first and second electrodes formed on the substrate with an insulating film and forming a contact hole to form a cathode on each light emitting layer; And forming a cathode electrode to be electrically connected to the first and second electrodes by using the partition wall.

Here, in order to implement the manufacturing method of the present invention, step (g) further comprises the step of forming a cathode electrode of the opaque metal using a shadow mask to function as a reflective film on the lower light emitting layer.

Here, in order to implement the manufacturing method of the present invention, the cathode electrode formed in the upper light emitting layer in step (e) may be a transparent metal, the cathode electrode formed in the lower light emitting layer may be an opaque metal.

Here, in order to implement the manufacturing method of the present invention, the first and second electrodes in step g) may be a ground electrode.

Here, in order to implement the manufacturing method of the present invention, the upper and lower light emitting layer may be formed with an organic light emitting layer.

Here, in order to implement the manufacturing method of the present invention, the upper emission layer and the lower emission layer by the cathode electrode formed on the first and second electrodes may be selected to emit light by double-sided emission or one surface.

Specific details of other embodiments are included in the detailed description and drawings.

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

First Embodiment

3A is a cross-sectional view of an electroluminescent device according to a first embodiment of the present invention, and FIG. 3B is a plan view showing the electroluminescent device of FIG. 3A on a plane.

Here, FIG. 3B is shown on a plane by removing the bonded transparent cover substrate for encapsulation for convenience of description.

As shown in FIG. 3A, a polysilicon layer 302 is formed on the transparent substrate 301, a gate electrode 304 is formed thereon, and the gate electrode 304 is a gate insulating film 305. It is insulated by. Meanwhile, active regions 303 are formed on both sides of the polysilicon layer 302. The source / drain electrodes 306a and 306b electrically connected to the active region 303 are formed through contact holes formed in the gate insulating layer 305. In addition, a passivation film or a flat film 307 is formed thereon.

The gate electrode 304 and the source / drain electrodes 306a and 306b constitute a switching element (not shown) or a driving element 320 of one driving unit, and the driving element 320 is shown here.

A lower light emitting anode electrode 308 is formed on the passivation film or the flat film 307 and is electrically connected to the drain electrode 306b in one direction, and the upper part is electrically connected to the drain electrode 306b in the other direction. A light emitting anode electrode 309 is formed.

Here, the lower light emitting anode electrode 308 and the upper light emitting anode electrode 309 are sequentially formed on the drain electrode 306b.

An insulating film 310 is formed above the region where the lower and upper light emitting anode electrodes 308 and 309 are formed, and a partition 311 is formed thereon.

On the other hand, the cathode 313 is formed on the upper emission layer 312a at the upper emission anode electrode 309, and the cathode 313 is formed on the lower emission layer 312b at the lower emission anode electrode 308. Separated by 311.

Here, as shown in FIG. 3B, the upper emission layer and the lower emission layer 312a and 312b have emission regions 350 formed in one pixel, respectively. In addition, an organic material layer is formed on the upper and lower light emitting layers 312a and 312b to form an organic light emitting device or an inorganic material layer to form an inorganic light emitting device.

On the other hand, the cathode electrode 315 is further formed on the lower emission layer 312b so as to function as a reflection film to prevent light from being reflected upward. That is, the cathode electrode 313 formed on the upper emission layer 312a and the lower emission layer 312b is separated by the partition 311, and the cathode electrode 315 which functions as a reflective film on the lower emission layer 312b is additionally formed. It is formed more.

Here, the cathode electrodes 313 formed on the upper and lower emission layers 312a and 312b are transparent metals, and the cathode electrode 315 formed on the lower emission layer 312b is an opaque metal.

When the cathode electrodes 313 and 315 are separated by the partition 311, the cathode electrodes 313 and 315 are formed to be adjacent to the emission region 350 and insulated from the insulating layer 325. The contact holes 322 formed in the 332 are electrically separated from each other.

That is, the cathode electrode 313 is electrically connected to each other through contact holes 322 formed on the first and second electrodes 331 and 332 to be separated from each other by the partition wall 311, and the cathode electrode 315 is In order to emit light, the first electrode 331 may be further formed on the first electrode 331 for the reflective film function.

However, when the cathode electrodes 313 and 315 are formed, an opaque metal component is formed on the first electrode 331 using a shadow mask and a transparent metal component is formed on the second electrode 332. You can also achieve your purpose.

Here, the first and second electrodes 331 and 332 are ground electrodes, and the electroluminescent elements 300a and 300b selectively emit light on both sides or one surface by selectively controlling the first and second electrodes 331 and 332. ) Is formed.

Meanwhile, the passivation layer 316 is formed on the electroluminescent devices 300a and 300b described above, and the passivation layer 316 is formed on the passivation layer 316 using the sealant 317 or the front adhesive. The transparent cover substrate 318 is bonded to encapsulate.

Here, the above-described upper light emitting anode electrode 309 and the lower light emitting anode electrode 308 may be formed in accordance with the purpose.

Accordingly, in the electroluminescent device described above, the cathode electrode for supplying electrons to the upper light emitting layer and the lower light emitting layer in one pixel is formed by a partition wall, and the cathode electrode is electrically connected to each other through a contact hole formed in the ground electrode insulated with the insulating film. Is connected to the electroluminescent device that selectively emits light on both sides or one surface by one driving unit.

<Production method>

4A to 4I are steps illustrating a step of manufacturing a double-sided light emitting device according to the manufacturing method of the present invention. Here, the part which cannot show a part of the manufacturing method on a plane is demonstrated with reference to sectional drawing, and the code | symbol of the same component is used for the understanding of description using the same code | symbol.

4A illustrates the steps of (a) forming a driving device 320 on the transparent substrate 301 and forming a passivation film or a flat film 307 on the drain electrode 206b of the driving device 320 and (b) ) Forming a contact hole in the passivation film or the flat film 307 to form the lower light emitting anode electrode 308 in any area other than the top of the driving device 320 so as to be electrically connected to the drain electrode 306b. .

A polysilicon (p-Si) layer 302 is formed on the transparent substrate 301, and then a gate electrode 304 is formed thereon. Thereafter, the active region 303 is defined by heat treatment using the gate electrode 304 as a mask. Thereafter, the gate insulating layer 305 is formed, and contact holes are formed to the active region 303, and then source / drain electrodes 306a and 306b are formed. Next, a passivation film or a flat film 307 is formed thereon to form the driving device 320.

The lower light emitting anode electrode 308 is electrically connected to the drain electrode 306b, and is formed in one of the regions other than the upper portion of the driving element 320 among the passivation film or the flat film 307.

Subsequently, FIG. 4B is a step of forming the upper emission anode electrode 309 on the other side of the region other than the upper portion of the driving device 320 to be electrically connected to the lower emission anode electrode 308.

The upper light emitting anode 309 is formed on the other side of the passivation film or the flat film 307 in an area other than the upper area of the driving element 320 so as to be electrically connected to the lower light emitting anode electrode 308. .

4C and 4D, the insulating film 310 is formed on the driving device 320 and the partition 311 is formed on the insulating film 310.

The insulating layer 310 is formed to separate and form the upper emission layer 312a and the lower emission layer 312b on a region where the upper and lower emission anode electrodes 309 and 308 overlap with each other, and a partition wall is formed on the insulating layer 310. 311).

Subsequently, FIG. 4E is a step of forming the light emitting layer such that (e) the upper light emitting layer 312a and the lower light emitting layer 312b are separated using the partition 311.

Each of the upper emission layer 312a and the lower emission layer 312b is formed on the front surface of the transparent substrate 310 by using the partition 311.

4F and 4G illustrate the first and second electrodes 331 and 332 formed on the transparent substrate 310 to form the cathode electrode 313 on each of the light emitting layers (f). Insulating and forming a contact hole 322.

The first and second electrodes 331 and 332 formed on the transparent substrate 310 are insulated from the insulating layer 325, and a contact hole 322 is formed. The first and second electrodes 331 and 332 may be formed on the left side and the right side of the light emitting region 350, respectively.

4H and 4I, the cathode electrode 313 is formed to be electrically connected to the first and second electrodes 331 and 332 by using the (g) barrier rib 311.

When the cathode electrode 313 is formed on the light emitting region 350, the upper light emitting layer 312a and the lower light emitting layer 312b are separately formed by the partition 311 on the light emitting region 350. In this case, the first and second electrodes 331 and 332 and the cathode electrode 313 are formed through the contact holes 322 formed in the first and second electrodes 331 and 332 formed at the left and right sides of the emission area 350. Each is electrically connected.

Here, in step (g), the method may further include forming the cathode electrode 315 of the opaque metal using the shadow mask 314 to function as a reflective film on the lower emission layer 312b.

Accordingly, the cathode electrode 315 is further formed on the cathode electrode 313 formed on the lower emission layer 312b, and the cathode 315 formed as a reflective film does not emit light toward the upper portion. Only the lower part will emit light. Here, the cathode electrode 315 is preferably made of a metal with high reflectance.

The electroluminescent device formed through the above-described process process may selectively emit both sides or selectively by one surface by the cathode electrodes 313 and 315.

Next, an electroluminescent device formed through the above-described process will be described with reference to FIG. 5.

5 is a view showing an electroluminescent device formed by the manufacturing method of the present invention.

As shown, encapsulation is performed in a vacuum atmosphere or an atmosphere in which moisture and oxygen levels can be controlled. In this case, a passivation layer 316 may be formed on the device before using the front adhesive or the front seal using the sealant 317.

Thereafter, when the encapsulation of the device is performed by adhering a glass cap or transparent cover substrate 318 onto the passivation layer 316 using a sealant 317 or a front adhesive. The electroluminescent device 500 according to the invention is formed.

According to the above-described process, by depositing the upper emission layer and the lower emission layer in one pixel, and providing a double-side light emitting electroluminescent device capable of selectively emitting the light emitting layer on both sides or selectively by one side, component cost and thickness of the device It is possible to reduce significantly.

Although the embodiments of the present invention have been described above with reference to the accompanying drawings, the above-described technical configuration of the present invention may be embodied in other specific forms by those skilled in the art to which the present invention pertains without changing its technical spirit or essential features. It will be appreciated that it may be practiced. Therefore, the embodiments described above are to be understood as illustrative and not restrictive in all aspects. In addition, the scope of the present invention is shown by the claims below, rather than the above detailed description. Also, it is to be construed that all changes or modifications derived from the meaning and scope of the claims and their equivalent concepts are included in the scope of the present invention.

According to the above-described configuration of the present invention, there is an effect of providing a double-emitting light emitting device capable of depositing an upper emitting layer and a lower emitting layer on one pixel, and selectively emitting the formed emitting layer on both sides or selectively by one side.

In addition, by forming an upper emission layer and a lower emission layer on each pixel, a double-sided electroluminescent device is implemented without any additional process, thereby significantly reducing component cost and thickness of the device.

Claims (12)

A light emitting region in which a partition is formed between an anode electrode and a cathode electrode electrically connected to a driving element formed on a substrate, and an upper emission layer and a lower emission layer are formed on both sides of the partition wall, respectively; First and second electrodes formed in parallel with the light emitting area and grounded to the ground; A plurality of contact holes for connecting the cathode electrodes of the emission region to the first and second electrodes Electroluminescent device comprising a. The method of claim 1, And the anode electrode is connected to any one of a source / drain electrode of the driving device. delete The method of claim 1, The cathode electrode formed on the upper light emitting layer is a transparent metal, the cathode electrode formed on the lower light emitting layer is an opaque metal. The method of claim 1, And an organic light emitting layer formed on the light emitting layer formed in the light emitting area. The method of claim 5, The upper light emitting layer and the lower light emitting layer by the cathode electrode formed on the first and second electrodes are characterized in that both sides of the light emission or selected by one surface to emit light. (a) forming a driving device on the transparent substrate and forming a passivation film or a flat film on the drain electrode of the driving device; (b) forming a contact hole in the passivation film or the planar film to form a lower light emitting anode electrode on one of the regions other than the upper portion of the driving device so as to be electrically connected to the drain electrode; (c) forming an upper light emitting anode electrode on the other side of the region other than the upper portion of the driving device to be electrically connected to the lower light emitting electrode; (d) forming an insulating film on the driving device, and forming a partition on the insulating film; (e) forming a light emitting layer such that an upper light emitting layer and a lower light emitting layer are separated using the partition wall; (f) insulating first and second electrodes formed on the substrate with an insulating film and forming contact holes to form cathodes on the respective light emitting layers; (g) forming the cathode electrode to be electrically connected to the first and second electrodes using the partition wall. The method of claim 7, wherein In the step (g), further comprising the step of forming a cathode electrode of the opaque metal using a shadow mask to function as a reflective film on the lower light emitting layer. The method of claim 7, wherein In the step (e), the cathode electrode formed on the upper light emitting layer is a transparent metal, the cathode electrode formed on the lower light emitting layer is a method of manufacturing an electroluminescent device, characterized in that the opaque metal. The method of claim 7, wherein In the step (g), the first and second electrodes are ground electrodes, characterized in that the manufacturing method of the electroluminescent device. The method according to any one of claims 7 to 10, The upper and lower light emitting layer is an organic light emitting layer is formed, characterized in that the manufacturing method of the electroluminescent device. The method of claim 11, The method of manufacturing an electroluminescent device according to claim 1, wherein the upper emission layer and the lower emission layer are selected to emit light on both sides or one surface by cathodes formed on the first and second electrodes.

Images