KR101798234B1 - Organic Light Emitting Display Device - Google Patents

Abstract

An embodiment of the present invention is a substrate processing apparatus comprising: a substrate; A transmissive electrode and a reflective electrode formed on a substrate; And an organic light emitting layer formed between the light transmitting electrode and the reflective electrode, wherein the light transmitting electrode has a thickness of the first region and a thickness of the second region different from each other.

Description

[0001] The present invention relates to an organic light emitting display device,

The present invention relates to an organic light emitting display.

An organic electroluminescent device used in an organic electroluminescent display device is a self-luminous device in which a light emitting layer is formed between two electrodes. The organic electroluminescent device injects electrons and holes from the electron injecting electrode and the hole injecting electrode into the light emitting layer, and excites the excited electrons and holes, And emits light when it is dropped to the ground state.

The organic light emitting display device using the organic electroluminescent device has a top emission mode, a bottom emission mode and a dual emission mode depending on a direction in which light is emitted, Passive matrix type and active matrix type according to the following.

In the organic light emitting display, when a scan signal, a data signal, a power supply, and the like are supplied to a plurality of subpixels arranged in a matrix form, the selected subpixel emits light, thereby displaying an image.

Conventional organic light emitting display devices use a micro cavity technology to achieve high color purity and high efficiency. The micro cavity technique is an optical technique that uses light emitted from the light emitting layer to interfere with light generated between translucent reflective layers of the anode electrode of the reflective layer of the cathode. A method of increasing color purity and efficiency by a micro cavity technique that causes a reinforcement effect by light interference in an organic light emitting display is achieved by a method such as adjusting the optical distance between two electrodes. However, the organic light emitting display device using the conventional micro cavity technology has the effect of improving the color purity throughout the panel. However, the improvement of the simple characteristics using the micro cavity can not be optimized for the R, G and B subpixels.

An embodiment of the present invention for solving the problems of the background art described above is an organic light emitting display device capable of improving the lifetime as well as increasing the efficiency by optimizing an element to which the micro cavity technology is applied for each R, . Further, the present invention provides an organic light emitting display device of high image quality and high efficiency based on optimization of devices.

According to an embodiment of the present invention, there is provided a semiconductor device comprising: a substrate; A transmissive electrode and a reflective electrode formed on a substrate; And an organic light emitting layer formed between the light transmitting electrode and the reflective electrode, wherein the light transmitting electrode has a thickness of the first region and a thickness of the second region different from each other.

The translucent electrode may occupy 5 to 95% of the area of the second region with respect to the area of the first region.

The translucent electrode may occupy 5 to 50% of the area of the second area with respect to the area of the first area.

The area ratio of the second area may be different for each R, G, and B sub-pixels.

The translucent electrode may include a first transparent metal, a second transparent metal, and a transparent metal formed between the first transparent metal and the second transparent metal.

The light-transmitting electrode may be divided into a first region and a second region by a thickness difference of at least one of the first transparent metal, the second transparent metal, and the transparent metal.

The translucent electrode may have a translucent property depending on the material of the translucent metal.

In the organic luminescent layer, the thickness of the first organic luminescent layer formed in the first region and the thickness of the second organic luminescent layer formed in the second region may be different.

In the organic luminescent layer, the positions of the first organic luminescent layer and the second organic luminescent layer may be different for each subpixel.

The reflective electrode may have a different thickness depending on the region.

The embodiment of the present invention is characterized in that at least one electrode portion of two electrodes in one subpixel is formed to include a first deposition region and a second deposition region which are different from each other, The organic electroluminescent display device according to the present invention can provide an organic electroluminescent display device capable of emitting light. In addition, the present invention can adjust the color, efficiency and lifetime according to the characteristics of the material by changing the material according to the separated regions as described above, and by combining them, The characteristics of the device can be improved, and an organic light emitting display device of high image quality and high efficiency can be manufactured.

1 is a structural view of a subpixel of an organic light emitting display according to an embodiment of the present invention;
2 is an example of a bottom film.
FIG. 3 is a simulation graph showing the relationship between the current and brightness of the device tested in Table 1. FIG.
FIG. 4 is a simulation graph showing the relationship between brightness and efficiency of the device tested in Table 1. FIG.
FIGS. 5 and 6 are simulation graphs showing the relationship between brightness and wavelength of the device tested in Table 5. FIG.
FIGS. 7 and 8 are simulation graphs showing the relationship between brightness and wavelength of the device tested in Table 9. FIG.
9 is a view showing the thickness and the arrangement of the light-transmitting electrodes for each light emission type.
10 is a view showing the arrangement of two organic light-emitting layers.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings.

1, a subpixel according to an embodiment of the present invention includes a substrate SUB, a lower film (TFT) formed on the substrate SUB, and a top film OLED formed on the lower film (TFT) .

The lower film (TFT) is a film in which a power wiring, a data wiring, a scanning wiring, a driving transistor, a switching transistor, a capacitor, and the like are formed. A buffer layer BUF, a gate insulating film GI, an interlayer insulating film ILD, a protective film PAS and a transparent electrode E1 are formed in the lower film (TFT). The buffer film BUF may be formed on the substrate SUB to protect the lower film (TFT) formed in the subsequent process from impurities such as alkali ions or the like that flow out from the substrate SUB. The buffer film (BUF) may be silicon oxide (SiOx). The gate insulating film GI may be formed on the buffer film BUF and a silicon oxide (SiOx) such as a buffer film BUF may be selected as a film insulating the gate electrode of the transistor. The interlayer film ILD is formed on the gate insulating film GI and is a film for separating the layers included in the lower film TFT. The interlayer film ILD is formed of the first interlayer film ILD1 and the second interlayer film ILD2, And is formed of the second interlayer film ILD2. Thus, when the interlayer film ILD is composed of two films, the first interlayer film ILD1 and the second interlayer film ILD2 may be selected from silicon oxide (SiOx) and silicon nitride (SiNx), respectively. The passivation layer PAS may be formed of silicon nitride (SiNx) as a film for protecting the transistors and the like included in the lower film (TFT), but is not limited thereto and may be formed as a multiple layer instead of a single layer as shown in the figure. The transparent electrode E1 is an electrode connected to the source or drain electrode of the driving transistor. The transparent electrode ITO1, the second transparent metal ITO1, the first transparent metal ITO1 and the second transparent metal ITO1, And a light transmitting metal (APC) formed therebetween. The first transparent metal (ITO1) and the second transparent metal (ITO2) may be selected from a transparent oxide metal such as indium tin oxide (ITO) and a transparent metal (APC) such as silver But is not limited thereto. The translucent electrode E1 may have translucency or translucency depending on the material of the translucent metal (APC).

The upper film OLED is a film which forms an organic light emitting diode together with a first electrode E1 formed on a lower film (TFT). An organic light emitting diode including an organic light emitting layer (EL) and a reflective electrode (E2) is formed in the upper film (OLED). The organic light emitting layer EL includes a hole injection layer (HIL), a hole transport layer (HTL), a light emitting layer (EML), an electron transport layer (ETL), and an electron injection layer (EIL). The reflective electrode E2 is selected as an opaque metal having a high reflectivity such as aluminum (Al).

An organic electroluminescent display device exhibiting a microcavity effect using a lower film (TFT) having the above-described structure is manufactured.

In the subpixel having the above structure, the color and the efficiency change depending on the thickness of the light transmitting metal (APC). For example, when the lower film (TFT) is formed in the structure shown in FIG. 2, the increase in the thickness of the translucent metal (APC) in green and red is caused by the increase in the micro- The color and efficiency are improved. On the other hand, in the case of blue, the color tone is improved but the efficiency is rapidly deteriorated.

In the following Tables 1 to 3, Lum denotes brightness, CIEx and CIEy denote x and y in CIE color coordinates. Table 1 below shows the characteristics of the blue subpixels, Table 2 shows the characteristics of the green subpixels, and Table 3 shows the characteristics of the red subpixels.

In Table 1 to Table 3, the thickness of the hole transport layer (HTL) differs for each RGB subpixel in order to investigate a characteristic change depending on the thickness of the light transmitting metal (APC) in an optimal environment shown by each device.

As shown in the previous experiment, the micro cavity structure exhibits the above-described characteristic difference for each RGB subpixel depending on the thickness of the light transmitting metal (APC). Accordingly, in the present invention, one of the problems to recognize and solve the above-mentioned characteristic difference is to divide the region of the light transmitting metal (APC) into the first region and the second region, The following experiment was conducted to investigate the relationship between

In the devices shown in Table 4, an insulating layer of a lower film (TFT) was formed on glass in the order of SiO 2 (3900 Å), SiN x (3150 Å) and SiN x (3600 Å) , 100 Å), a light transmitting metal (APC, 100 Å or 200 Å) and a second transparent metal (ITO, 100 Å). Thereafter, a reflective electrode (Al, 1500 Å) was formed by depositing HIL (50 Å), HTL (800 Å, 850 Å or 900 Å), EML (300 Å 4%), ETL (200 Å) and EIL (LiF, 10 Å)

In Table 4, V denotes the voltage, cd / A denotes the brightness, Im / W denotes the current, CIE_x and CIE_y denote the quantum efficiencies of x and y in the CIE color coordinates, and EQE (%). Table 4 below shows the characteristics of a blue subpixel, and NPD is an HTL material.

As can be seen from Table 4 and the graph of FIG. 3 and the graph of FIG. 4, even if the materials used for the device are the same, a change in characteristics occurs when the thickness of the light transmitting metal (APC) is changed.

The devices used in the experiment of Table 5 were formed by forming an insulating layer of a lower film (TFT) in the order of SiO 2 (3900 Å), SiN x (3150 Å) and SiN x (3600 Å) , 100 Å), a light transmitting metal (APC, 100 Å or 200 Å) and a second transparent metal (ITO, 100 Å). Thereafter, a reflective electrode (Al, 1500 Å) was formed by depositing HIL (50 Å), HTL (1000 Å or 1400 Å), EML (300 Å 4%), ETL (200 Å) and EIL (LiF, 10 Å)

In the following Table 5, V denotes the voltage, cd / A denotes the brightness, Im / W denotes the current, CIE_x and CIE_y denote the quantum efficiencies of x and y in the CIE color coordinates, and EQE (%). Table 5 below shows the characteristics of the blue subpixels, and NPD is the HTL material.

As can be seen from the graph of Table 5 and the graph of FIG. 5 and the graph of FIG. 6, when the thickness of the light transmitting metal (APC) decreases (transmittance increases, reflectance decreases) even though the materials used for the devices are the same, a shoulder peak . Here, the graph of FIG. 5 shows a case where the thickness of the HTL is 1000 ANGSTROM, the graph of FIG. 6 shows the HTL thickness of 1400 ANGSTROM, and the shoulder peak refers to the circle portion of the dotted line shown in FIGS. 5 and 6.

According to the above experiment, when the light-transmitting metal (APC) is divided into the first region (main region) and the second region (auxiliary region) and the element of Table 5 is used as the electrode of the auxiliary region, The effect of the shoulder peaks of the regions can be exerted together to improve color and efficiency.

In addition, the following experiment was carried out in order to examine the change of the thickness of one of the first transparent metal (ITO1) and the second transparent metal (ITO1) and the change of the characteristics of the device due to the change of the thickness of the translucent metal (APC) .

The devices used in the experiment of Table 6 are formed by sequentially forming SiO 2 (3900 Å), SiN x (3150 Å) and SiN x (3600 Å) on glass and then forming a first transparent metal (ITO , 100 Å), a light transmitting metal (APC, 150 Å or 200 Å) and a second transparent metal (ITO, 100 Å or 200 Å). Thereafter, a reflective electrode (Al, 1500 Å) was formed by depositing HIL (50 Å), HTL (1000 Å), EML (300 Å 4%), ETL (200 Å) and EIL (LiF, 10 Å)

In the following Tables 6 to 8, V denotes the voltage, cd / A denotes the brightness, Im / W denotes the current, CIE_x and CIE_y denote quantum efficiencies of x and y in the CIE chromaticity coordinates and EQE (%). Table 6 below shows the characteristics of the red subpixels, Table 7 shows the characteristics of the green subpixels, and Table 8 shows the characteristics of the blue subpixels.

As shown in Table 6, when the thickness of the transparent metal (APC) and the second transparent metal (ITO1) is large in the case of a red subpixel, the color and efficiency are improved.

As shown in Table 7, in the case of the green subpixel, the thickness of the translucent metal (APC) is thick and the thickness of the second transparent metal (ITO1) is thin, the color and efficiency are improved.

As shown in Table 8, once the thickness of the translucent metal (APC) is increased in the case of a blue sub-pixel, the micro-cavity effect is increased but the color and efficiency are degraded.

According to the above experiment, the color and efficiency of the blue subpixel are sensitively changed by the thickness variation of the light transmitting metal (APC) with respect to the subpixel of the other color. Therefore, the light transmitting metal (APC) included in the blue subpixel is divided into the first area (main area) and the second area (auxiliary area). Based on the above experiment, the following results are obtained.

In Table 9, cd / A is the brightness, CIE_x and CIE_y are x and y in the CIE color coordinates, and Remark means whether the efficiency is increased. Table 9 below shows the characteristics of a blue subpixel.

As can be seen from the graphs of Table 9, FIG. 7 and the graph of FIG. 8, when the blue subpixel is divided into the first region (main region) and the second region (auxiliary region) The main peak of the main region and the shoulder peaks of the auxiliary region coexist together to improve color and efficiency.

Referring to FIG. 7, when the thickness of the transmissive metal (APC) decreases, the shoulder peaks are improved when the thickness is reduced (the transmittance is improved and the reflectance is lowered). Therefore, the main peak of the main region and the shoulder peak of the auxiliary region Color and efficiency can be improved. Referring to FIG. 8, the translucent metal (APC) can change the color and efficiency according to the ratio of the main region and the auxiliary region, and also can select a ratio suited to the target color.

Therefore, in the case of a device using a micro-cavity structure, the light-transmitting electrode APC included in the transparent electrode E1 is divided into a first region (main region) and a second region (auxiliary region) If the thickness of the two regions is different, the characteristics of the device can be changed. Therefore, in the embodiment, the light-transmitting electrode E1 is divided into the first region A1 and the second region A2 regardless of the bottom emission type of FIG. 9 (a) or the top emission type of FIG. 9 (b) The characteristics of the device can be changed by varying the thickness. Here, EML means all layers included in the organic light emitting layer.

As can be seen from the above experiment, the light transmitting electrode (APC) can be formed so that the area of the second region occupies 5 to 95% of the area of the first region. More preferably, the translucent electrode APC is formed so that the area of the second region occupies 5 to 50% of the area of the first region. In addition, as shown in the above experiment, the area ratio of the second region divided into the light-transmitting electrode (APC) can be different for each R, G, and B subpixel.

In the above experiments, only the transmissive electrode E1 including the transmissive electrode APC has been described, but the characteristic of the micro-cavity structure is also changed by the reflective electrode E2. Therefore, the reflective electrode E2 may be divided into the first region and the second region based on the above experiment, and the thickness may be different according to the region.

In the embodiment, only the characteristic test of the device according to the change of the thickness of the light transmitting metal (APC) and the second transparent metal (ITO2) has been started. However, those skilled in the art will understand that the first transparent metal (ITO1) By dividing the thickness of at least one of the second transparent metal (ITO2) and the light transmitting metal (APC) into the first region and the second region, similar or similar effects as those of the present invention can be obtained.

10, the first organic emission layer EML1 and the second organic emission layer EML2 are divided into a first region and a second region, and the thickness of the first organic emission layer EML1 formed in the first region And the thickness of the second organic emission layer EML2 formed in the second region may be different. In addition, the positions of the first organic emission layer (EML1) and the second organic emission layer (EML2) may be formed to be different for each subpixel. 10 (a) shows that the first organic emission layer EML1 and the second organic emission layer EML2 are disposed only in one direction, FIG. 10 (b) 2 organic light emitting layer (EML2) are arranged alternately.

As described above, the organic light emitting layer is divided into the first organic light emitting layer (EML1) and the second organic light emitting layer (EML2) in correspondence to the first region and the second region, and the thickness, material, 10-2009-0098658.

As described above, according to the present invention, at least one electrode portion of two electrodes in one subpixel is formed to include a first deposition region and a second deposition region which are different from each other, There is an effect of providing an organic electroluminescent display device. In addition, the present invention can adjust the color, efficiency and lifetime according to the characteristics of the material by changing the material according to the separated regions as described above, and by combining them, The characteristics of the device can be improved, and an organic light emitting display device of high image quality and high efficiency can be manufactured.

While the present invention has been described in connection with what is presently considered to be practical exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, It will be understood that the invention may be practiced. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. In addition, the scope of the present invention is indicated by the following claims rather than the detailed description. Also, all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included within the scope of the present invention.

SUB: Substrate TFT: Lower film
OLED: Upper film PAS: Shield film
E1: Transparent electrode E2: Reflective electrode
EML1: First organic luminescent layer EML2: Second organic luminescent layer

Claims (11)

Board;
A light-transmitting electrode and a reflective electrode formed on the substrate; And
And an organic light emitting layer formed between the transmissive electrode and the reflective electrode,
The light-
Wherein a thickness of the first region and a thickness of the second region are different from each other, and an area ratio of the second region is R, G, B Different for each subpixel,
The organic light-
A first organic light emitting layer formed in the first region and a second organic light emitting layer formed in the second region, wherein the position of the first organic light emitting layer and the position of the second organic light emitting layer are alternately Emitting display device. The method according to claim 1,
The light-
Wherein an area of the second region is 5 to 95% of an area of the first region. The method according to claim 1,
The light-
Wherein an area of the second region is 5 to 50% of an area of the first region. delete The method according to claim 1,
The light-
A first transparent metal, a second transparent metal, and a light-transmitting metal formed between the first transparent metal and the second transparent metal. 6. The method of claim 5,
The light-
Wherein the first region and the second region are divided by a thickness difference of at least one of the first transparent metal, the second transparent metal, and the transparent metal. delete The method according to claim 1,
The organic light-
Wherein a thickness of the first organic light emitting layer formed in the first region is different from a thickness of the second organic light emitting layer formed in the second region. delete The method according to claim 1,
The reflective electrode
Wherein the thickness of the region corresponding to the first region is different from the thickness of the region corresponding to the second region. The method according to claim 1,
The thickness of the first region and the thickness of the second region are set so that,
R, G, and B subpixels.

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