KR20130141016A - Thermal and non-thermal repair system for amoled - Google Patents

Abstract

The present invention relates to a thermal and non-thermal repair device for an AMOLED. The purpose of the present invention is to provide the thermal and non-thermal repair device for the AMOLED, capable of economically and efficiently being commercialized by efficiently performing a process according to various conditions by performing a complex repair for a thermal process and a non-thermal process by selectively using pulse lasers with various pulse widths at need.

Description

Thermal and Non-thermal Repair System for Active Organic Self-Emitting Device {Thermal and non-thermal repair system for AMOLED}

The present invention relates to a thermal and non-thermal complex repair device of an active organic self-luminous device.

Recently, a display using an active organic light emitting diode (AMOLED) has advantages such as self-luminescence compared to a liquid crystal display (LCD), power consumption is much more efficient than other conventional devices , It is receiving the spotlight as a next generation display. As a result, the use thereof from display of small portable devices to display of a large area gradually increases.

An active organic light-emitting device typically comprises two electrodes and organic light-emitting layers therebetween. Electrons and holes are injected into the organic light emitting layer through the electrode, and the light is emitted while changing the current into visible light. 1 illustrates a configuration of an active organic self-light emitting device. In more detail, FIG. 1 (A) shows a schematic configuration of an active organic self-light emitting device, and FIG. 1 (B) shows an implementation configuration and a conceptually simplified configuration of an active organic self-light emitting device formed of a top emission type, respectively. Doing.

On the other hand, such an active organic light emitting device may have a potential problem expressed as a defective pixel due to an error during the production process of the product, an unintended shape of the electrode due to heat, instability between the organic light emitting layers, and the like. Such defective pixels deteriorate the value of the product and become a fatal weak point of the display device manufactured using the active organic light emitting device.

In the conventional display such as LCD, defective pixels are often generated due to the above reasons. In this case, a process of repairing the laser by irradiating the laser using the laser equipment is generally used. However, current active organic light-emitting devices are subject to alteration or alteration of the materials constituting the active organic light-emitting device when heat of 100 ° C or more is applied thereto. Therefore, when a laser device used for repairing a display such as a conventional LCD is used for repairing an organic self-luminous device, there is a problem that a peripheral portion of the target is inevitably damaged by laser beam irradiation.

The laser equipment used in the past mostly uses a nanosecond laser, the nanosecond laser is subjected to such thermal deformation, so there is a problem that unnecessary damage occurs, while also having the advantage of high output and stable output. On the other hand, femtosecond lasers, which are mainly used at the laboratory level rather than being widely commercialized, are excellent in that they can be processed with high precision due to their non-thermal and material-independent characteristics, but on the other hand, the output is low and the process speed is high. Is relatively slow, and it is not suitable to apply it in actual field when considering production efficiency.

Due to the lack of such a suitable laser repair technology, all active organic self-light emitting devices in which a defective circuit pixel is generated in a mass production process are currently discarded. In the case of active organic self-light emitting device products applied to small products, if a malfunction occurs in the finished product, even if it is disposed of as it is, the size of the product itself is small (that is, it is not a large area). It is considered to be. However, the active organic self-light emitting device technology has recently been applied to not only small displays but also products such as large-area TVs. Therefore, in case of producing an active organic self-light emitting device TV product, if a defect or error occurs in the product, a fatal loss in terms of production yield occurs if the entire quantity is discarded without repairing. Considering these points, it is necessary to develop a process technology and an apparatus capable of efficiently producing and repairing an active organic self-light emitting device.

Various techniques for repairing a display device including such an active organic light emitting device have been disclosed.

Korean Patent Laid-Open Publication No. 2011-0137460 (Dec. 23, 2011, "Laser Repairing and Repairing Method", hereinafter referred to as Prior Art 1) discloses a laser device for irradiating a defective pixel- do. The apparatus of the prior art 1 particularly uses a beam expander capable of enlarging the size of the laser beam and a slit capable of reducing the size by passing only a part of the laser beam so that the size of the laser beam To be changed. However, as described above, the apparatus of the prior art 1 still has a problem of causing thermal deformation of the material as in the general laser processing equipment currently used, and thus can not be used for repairing the active organic light emitting device.

Japanese Patent Laid-Open Publication No. 2011-071032 (Apr. 04, 2011, "Organic EL device and its repair method and manufacturing method", hereinafter referred to as Prior Art 2) discloses a method in which foreign matters are stuck between stacked layers in the course of manufacturing an organic light- A microlens is formed on one side of the organic light emitting device so as to repair the organic light emitting device, and a repair technique using the organic light emitting device. In the prior art 2, the focal point position of the microlenses is formed so as to be the same as the position where the foreign object exists, and the laser is irradiated through the microlenses, thereby accurately irradiating the laser through the microlenses to foreign matter, So that the foreign object can be removed. However, in the prior art 2, since the process of placing the microlenses accurately focused on the corresponding portions when the defects occur is substantially difficult, there is a problem that it takes much time to perform such a placement process. In addition, the defects generated in the display manufacturing process exist in various forms as well as foreign matter contamination. According to Prior Art 2, it is difficult to use defects other than foreign matter contamination to repair.

1. Korean Patent Laid-Open Publication No. 2011-0137460 (December 23, 2011, "Laser Repair Device and Repair Method") 2. Japanese Patent Laid-Open Publication No. 2011-071032 (April 04, 2011, "Organic EL device and its repair method and manufacturing method")

Accordingly, the present invention has been made to solve the problems of the prior art as described above, and an object of the present invention is to selectively use pulse lasers having various pulse widths in parallel, as necessary, that is, thermal processing and non-thermal. The thermal and non-thermal complex repair device of an active organic self-emitting device, which is intended to enable a complex repair that can be processed in all, and to enable the most efficient process progress according to various conditions, thereby enabling economical and efficient commercialization. In providing.

The thermal and non-thermal complex repair device of the active organic self-light emitting device of the present invention for achieving the above object, the failure of the active matrix organic light emitting diode (AMOLED) that is the object 500. A device 100 for repairing a pixel, the unit laser light sources 111a, 111b, 111c and at least two different pulse widths, and the unit laser light sources 111a, 111b, 111c. A laser light source 110 comprising a selector 112 for selecting one of the laser lights generated in the laser beam; A lens unit 120 for irradiating the laser generated by the laser light source 110 to a part to be processed of the object to be processed 500; A stage 130 on which the processing object 500 is placed, the stage 130 being movable in three X, Y, and Z axis directions relative to the lens unit 120; A photographing unit 140 photographing a part to be processed of the object 500 to obtain image information; A controller 150 for controlling three-axis movement of the lens unit 120 or the stage 130 using the image information acquired by the photographing unit 140; And a control unit.

In this case, the selector 112 may include at least two mirrors 112a for adjusting and integrating the optical paths of the laser light generated by the unit laser light sources 111a, 111b, and 111c, and the optical paths And a shutter 112b disposed on the optical path of the integrated laser light.

In addition, the repair apparatus 100 may include a slit part 160 disposed on an optical path of a laser generated by the laser light source 110 to adjust a laser beam size so that a slit for passing only a part of the laser is formed; And further comprising: At this time, the slit portion 160 is preferably formed in a form in which at least one or more slits formed different in size or shape are spaced apart from each other. In addition, the slit 160 is preferably formed to be movable by the controller 150.

In addition, the repair apparatus 100 includes the laser light source 110, the lens unit 120, and the photographing unit 150 modularized and provided in one gantry, and together with the control unit 150. The laser light source 110, the lens unit 120, the photographing unit 150, and the slit unit 160 may be modularized and provided in one gantry, and may be formed to be movable. It characterized in that it is formed to be movable together by 150).

According to the present invention, by using a combination of pulse lasers having various pulse widths from nanoseconds to femtoseconds, it is possible to select the pulse laser of the pulse width most advantageous to the conditions according to various conditions to improve the process speed, process stability and ultra precision There is a big effect to satisfy all the processing. More specifically, a nanosecond laser is a thermal process, which causes damage to materials, making it difficult to perform ultra-precision processing, but enables a high-powered, fast and stable process, while a femtosecond laser has a low output and a slow process speed. And material-independent processing enables ultra-precision processing. In the case of picosecond laser, it has the intermediate characteristics of nanosecond laser and femtosecond laser, and nanosecond laser is used for repair process or cutting process of materials that do not cause significant thermal deformation. And femtosecond laser can be used for the processing of materials where thermal deformation can be a problem, or for the repair process of very small areas. Therefore, the process efficiency is maximized The.

1 is a configuration of an active organic self-light emitting device.
2 is a comparison of the processing characteristics of nanosecond and femtosecond lasers.
3 is a corresponding example of lasers of various pulse widths suitable for the various components of the active organic self-luminous device panel and their respective processing.
4 is a schematic diagram of one embodiment of a repair apparatus configuration of the present invention.
5 is an embodiment of a selector;
6 is an example processed by irradiation with a nanosecond laser.
7 is an example processed by irradiating picosecond laser.
8 is an embodiment of a slit portion.
9 is an example of processing by irradiating a laser beam adjusted to a square shape and various sizes using different slits in the femtosecond laser processing by varying the irradiation time.
10 is a graph of femtosecond laser repair thresholds (expressed in peak intensity) for a single layer.
11A to 11I are graphs showing the ablation rate in the depth direction according to the change in intensity and the number of pulses based on a femtosecond laser threshold for each single layer.

Hereinafter, a thermal and non-thermal complex repair apparatus of an active organic self-light emitting device according to the present invention having the above configuration will be described in detail with reference to the accompanying drawings.

In a product made of a highly integrated circuit such as a display, defects generated in a manufacturing process include defects generated by incorporation of a foreign substance in a manufacturing process, defects generated due to a failure in performing a process completely, There are various types such as a short defect connected between the conductors to be connected and an open defect where the wiring is interrupted. The method of repairing various defects will vary depending on the type and nature of defects, but in general, laser correction techniques are widely used. For example, in the case of adhesion of foreign matter or shot defect, defects are repaired by irradiating laser light to a position of a foreign substance such as particles or resist adhered to the surface of the FPD substrate or a part of an improperly formed metal wiring .

Pulsed laser is a pulse width (pulse width) as to the nanosecond laser (the number to several hundred ns (laser for outputting a laser beam having a pulse width of 10 ^-9 seconds)), picosecond lasers (number to several hundred ps (10 standard ^- Laser beams having a pulse width of ¹² seconds), femtosecond lasers (lasers outputting laser light having a pulse width of several to several hundreds fs (10 ^-15 seconds)), and the like. The pulse width is one of several performance indicators of the pulse laser that determine the state of the object after processing. The longer the pulse width, the more clearly the effect of thermal processing by the laser on the object becomes apparent.

Nanosecond lasers have advantages such as high laser power and stability of power that can be processed on large area objects, while the effect of heat processing on objects becomes more pronounced than picosecond or femtosecond lasers. In the current laser processing technology, nanosecond lasers are widely used due to advantages such as large area processing capability and output stability. However, as described above, in the case of the nanosecond laser, as shown in FIG. 2 (A), the shock wave is generated at the laser irradiation site, the surface is distorted, the microcracks propagate into the part, and the laser irradiation site is also very hot. This causes a problem that the surrounding material is deteriorated by heat as a molten layer in which a portion of the substrate material is melted is generated, and thus, there is a limit in that it is difficult to use in the case of precise processing or a material sensitive to thermal deformation.

Picosecond lasers are pulse lasers with shorter pulse widths and longer pulse widths than femtosecond lasers (to be described later), which have less thermal processing effects than nanosecond lasers, but are higher than femtosecond lasers. That is, it has an intermediate characteristic. However, picosecond lasers can produce higher power than conventional femtosecond lasers, and thus have relatively high speeds.

The femtosecond laser is a laser having a shorter pulse width than the nanosecond laser and the picosecond laser, and as shown in FIG. 2 (B), plasma is generated and processed instead of generating heat at the laser light irradiation site. Therefore, unlike when using a nanosecond laser, heat and shock waves are not generated at all, so the problem of the formation of molten layer and the surrounding material deterioration, or the surface damage and microcracks propagation problems caused by the shock waves are fundamental. Will be solved. In other words, the femtosecond laser can realize a high non-thermal processing result, and the laser processing can be performed regardless of the material, which is very suitable for ultra-precision processing. However, it has a lower power and process speed than nanosecond lasers and picosecond lasers, so it is difficult to apply them directly to industrial sites.

As described above, since the active organic light-emitting device is particularly more sensitive to heat than conventional LCDs, it is almost impossible to repair defects by using a conventional nanosecond laser or the like. However, as can be seen from the comparison of FIG. 2, it is possible to apply a non-thermal process to a repair technique of an active organic light emitting device when using an ultra-short pulse laser such as a femtosecond laser. On the other hand, in the case of processing a PCB substrate for driving the active organic self-light emitting device panel, processing using a femtosecond laser may result in a very low process efficiency due to low power and low speed characteristics. Therefore, nano-second lasers are much more economical and efficient when processing objects that do not have high thermal sensitivity and do not require high precision processing.

At this point, in the present invention, as a method of repairing an active matrix organic light emitting diode (AMOLED), a laser having a variety of pulse widths is provided in parallel and selectively used. We present a device that maximizes process efficiency by using the optimal laser for the conditions.

As described above, in the case of an active organic self-light emitting device panel, the active organic self-light emitting device itself is highly thermally sensitive and requires ultra-precision processing, whereas a module part such as a PCB substrate on which the devices are disposed is low in heat sensitivity and relatively Machining precision does not have to be high. 3 shows a corresponding example of various components of the active organic self-light emitting device panel and lasers of various pulse widths suitable for their respective processing in view of this point. In the case of OLED element part, Low Temperature Poly Silicon (LTPS) part, and Thin Film Transistor (TFT) part (for driving active organic self-light emitting device), it is desirable to use a femtosecond laser that has high thermal sensitivity and requires ultra-precision processing. In addition, it is preferable to use a picosecond laser, a nanosecond laser, etc. as a board | substrate part.

Hereinafter, the configuration of the thermal and non-thermal complex repair apparatus of the present invention which actually implements this concept will be described. 4 shows a schematic diagram of one embodiment of a repair apparatus configuration of the present invention. As shown, the non-thermal repair apparatus 100 of the active organic self-light emitting device of the present invention is a device capable of repairing defective pixels of the active organic self-light emitting device of the object 500, and includes a laser light source 110 and a lens. The unit 120, the stage 130, the photographing unit 140, the controller 150, and the like are formed.

The laser light source 110 is formed to generate pulsed laser light. In this case, in the present invention, the unit laser light sources 111a, 111b, 111c and the unit laser light sources 111a, 111b, 111c have at least two different pulse widths. It includes a selector 112 for selecting one of the laser light generated by the. As described above, the unit laser light sources 111a, 111b, and 111c may be at least two or more selected from among nanosecond lasers, picosecond lasers, and femtosecond lasers. For example, the laser light source 110 is made of [nanosecond laser / picosecond laser], [picosecond laser / femtosecond laser], [nanosecond laser / femtosecond laser], or [nanosecond laser] / Picosecond laser / femtosecond laser] (the embodiment of Figure 4) can be made in various combinations. Of course, the present invention is not limited thereto. For example, when the Atosecond laser having a shorter pulse width than the femtosecond laser can be realized and stable operation is possible, the laser light source 110 may be [nanosecond laser]. Laser beam forming the laser light source 110 may be determined in various ways without departing from the spirit of the present invention.

The selection unit 112 may be in any form as long as it is formed to select any one of the laser lights generated by the unit laser light sources 111a, 111b, and 111c. FIG. 5 illustrates one embodiment of the selector 112. The embodiment of FIG. 5 illustrates an efficient and simple configuration in which the selection unit 112 can be implemented. The selection unit 112 may include at least two mirrors 112a for adjusting and integrating optical paths of laser light generated by the unit laser light sources 111a, 111b, and 111c, and the optical paths may be integrated. And a shutter 112b disposed on the optical path of the laser light. In such a configuration, laser light having a desired pulse width can be easily selected by adjusting the opening and closing speed of the shutter 112b. As a case where the laser light source 110 is composed of [nanosecond laser / femtosecond laser] as follows. When the shutter 112b is opened and closed according to the pulse width of the nanosecond laser, the laser light in which the nanosecond laser and the femtosecond laser are combined is output through the shutter 112b. The effect of the weak femtosecond laser does not appear much. Therefore, the nanosecond laser may be used alone or similarly, and processing such as substrate cutting may be performed. Alternatively, when the shutter 112b is opened and closed according to the pulse width of the femtosecond laser, only the femtosecond laser is passed through the shutter 112b and the nanosecond laser is not passed, so that only the femtosecond laser can be used for processing. By changing the opening / closing speed of the shutter 112b appropriately, laser light having a desired pulse width can be easily output selectively.

The lens unit 120 irradiates the laser beam generated by the laser beam source 110 onto the object to be processed of the object to be processed 500, that is, it functions to align the laser focus to the object to be processed. The stage 130 has the processing object 500 placed thereon, and the lens unit 120 and the stage 130 are formed to be movable in the X, Y, and Z axis directions relative to each other. The stage 130 may be generally made of a vacuum chuck device. In this manner, a repair or the like may be performed while stably fixing the workpiece 500 therebetween. The photographing unit 140 photographs a part to be processed of the object 500 to acquire image information. The control unit 150 acquires information on the machining state such as how much machining has been performed using the image information acquired by the photographing unit 140 and performs three-axis movement of the stage 130 Respectively.

FIG. 6 shows an example in which aluminum nanosecond lasers are irradiated and processed using aluminum under conditions of a pulse width of 20 ns, a wavelength of 532 nm, a repetition rate of 40 kHz, and a processing speed of 10 mm / s. Fig. 7 shows an example in which aluminum is processed under conditions of a pulse width of 40 ps, a wavelength of 532 nm, a repetition rate of 40 kHz, and a processing speed of 10 mm / s. In addition, the repair apparatus 100 is a slit disposed on the optical path of the laser generated by the laser light source 110 to adjust the size of the laser beam irradiated to the processing target portion, the slit is formed to pass only a portion of the laser Unit 160; And the like. The use of such slits is suitably used in ultra precision processing, that is, when the laser output from the laser light source 110 is a femtosecond laser. By passing through the slit, the laser beam can be reduced in size or limited in shape, thereby enabling very precise microfabrication, and considering the size level of defects generated in the active organic self-emitting device, the slit is used for such a repair process. It is preferable that the silver size is in the range of 1 μm × 1 μm to 10 ² μm × 10 ² μm. FIG. 8 illustrates an embodiment of a slit part. As such, the slit part 160 may be formed such that at least one or more slits formed of different sizes or shapes are spaced apart from each other. In this case, the slit part 160 is also formed to be movable by the controller 150, so that the slit of a desired size or shape can be easily changed and disposed. 9 is an example of processing by irradiating a femtosecond laser, in particular, a laser beam adjusted to a rectangular shape and various sizes using a slit to irradiate different processing time, pulse width 90fs, wavelength 795nm, repetition rate 10kHz, Aluminum was made into the object on condition of 1 second of irradiation time.

In addition, as shown in FIG. 4, the repair apparatus 100 includes the laser light source 110, the lens unit 120, and the photographing unit 150 modularized in one gantry. Is provided, it is preferable to be formed to be movable together by the control unit 150. In this way, the repair can be easily performed while moving the gantry with respect to a large-area product such as an AMOLED TV panel. Of course, when the repair apparatus 100 includes the slit portion 160, the slit portion 160 is modularized together in the gantry. As described above, the repair apparatus 100 of the present invention, in particular, in the production of large-area active organic self-light emitting device products such as AMOLED TV panels, can be used by repairing them without discarding them even if defects occur. It can be maximized.

The repair apparatus of the present invention as described above preferably comprises all of a nanosecond laser, a picosecond laser, and a femtosecond laser. The following table summarizes the classification and characteristics of the laser in these cases and the preferred processing conditions (pulse width, wavelength, repetition rate).

In the case of nanosecond laser processing, there are many products that are commercially available as laser processing apparatuses, and thus they are widely used, and thus, no special preparation for processing is required. In addition, as described above, in the present invention, nanosecond laser processing is used for cutting substrates or repairing panel parts (relatively less thermally sensitive than active organic self-emitting devices), that is, not for ultra-precision processing. It is not much different from the laser processing conventionally used in processing conditions.

On the other hand, in the case of femtosecond laser processing, simply using a femtosecond ultra-short pulse laser for non-thermal and material-independent high precision processing cannot be easily repaired. As shown in FIG. 1 and the like, the active organic light emitting device is formed by stacking layers of various materials such as an electrode layer and an organic layer. In this case, as described above, there are various types of defects such as a foreign matter defect, a shot defect, an open defect and the like. For example, in the case of a foreign material defect, a short defect, etc., the defect may be repaired by removing only a part of the stacked layers . Therefore, in such a case, it is necessary to control not only the entire composite layer but also the outermost portion of the composite layer so as to be able to selectively repair the desired layer without damaging it. For this purpose, active absorptivity It is necessary to grasp characteristic information for each layer constituting the self light emitting element.

Therefore, femtosecond laser processing is first performed by including a preparatory step of grasping such characteristic information and determining the processing conditions, and a machining step of performing the actual processing using the processing conditions determined in the preparation step. Of course, in the case of processing with a picosecond laser having an intermediate characteristic of nanosecond laser and femtosecond laser, the steps described below may be partially applied.

First, the preparation step will be described. In the preparation step, the processing conditions including the threshold value of the laser are determined according to the physical properties or morphological characteristics of the respective layers constituting the active organic light emitting device.

In this case, the physical property of the layer refers to the absorption rate with respect to the wavelength, and the morphological characteristic of the layer refers to the layer thickness and the like. The threshold value of the laser refers to the minimum energy for changing the target portion of the target layer to be repaired. That is, unless the irradiated laser exceeds this threshold value, the target portion is changed. The threshold is naturally determined by the physical properties and morphological characteristics of the layer to be repaired. As a result of various experiments performed by the present applicant on each layer constituting actual active organic light emitting device (which will be described in more detail in the following embodiments), the threshold value is 10 ⁹ W / cm ² to 10 ¹² W / cm < ^{2 &} gt ;.

In addition, the processing conditions may include not only threshold values but also various elements. More specifically, the processing conditions may include the pulse width, wavelength, pulse energy, repetition rate, irradiation time, etc. of the laser.

The pulse width will be described as follows. The pulse width is one of the factors that represent the performance of the pulse laser. As described above, when the pulse width is in the range of 10 < ^-9 > s, thermal deformation of the material can not be prevented, and micro cracks are generated and propagated. Therefore, it is very important to limit the pulse width, and the shorter the pulse width, the higher the non-thermal processing can be achieved. In the present invention, the ultrashort pulse laser is a laser having a shorter level than a nanosecond, that is, a 10 ^-12 s laser, a 10 ^-15 s laser, a 10 ^-18 s laser, or the like. In particular, in the case of picosecond laser, the adverse effects of the nanosecond laser may not be completely removed according to the conditions. In the case of the Atosochi laser, the femtosecond laser is not widely used so as to be commercially available as a current technology. It would be most desirable to use. According to the results of the inventors performing various experiments on each layer of the active active organic self-light emitting device (as will be described in more detail below), the ultra-short pulse laser has a pulse width in the range of 1 fs to 1 ps. Most preferred.

A description of the wavelength is as follows. In order to selectively process a layer, it is necessary to grasp a wavelength region having a high absorption rate for each layer. For example, in the middle of a multiple layer, an A-layer repair consisting of a material with a high absorption rate at a wavelength of 800 nm is required. The other B layer located on the path of the laser beam irradiation has a low absorption rate at 800 nm. In this case, it is possible to repair the A layer, which is the target layer, without causing unnecessary damage to the B layer by allowing the ultra-short pulse laser to irradiate a laser having a wavelength of 800 nm. As described above, it is possible to grasp the absorption rate depending on the wavelength for each layer and to determine which wavelength to choose for repairing in advance, thereby performing more precise repair processing. According to the results of the inventors performing various experiments on each layer constituting the actual active organic self-emitting device (as will be described in more detail in the following embodiments), the ultra-short pulse laser has a wavelength of 10 ² nm to 10 ⁴ nm. It is preferable to exist in the range.

The pulse energy is described as follows. In order to understand femtosecond laser processing according to the present invention, it is important to identify a threshold as described above. This threshold value is directly related to the pulse energy of the laser, i.e., in the preparation step, an experiment to identify the minimum pulse energy to change the material of the target point substantially is performed first. According to the results of the inventors performing various experiments on each layer constituting the actual active organic self-emitting device (as will be described in more detail in the following examples), the ultra-short pulse laser has a pulse energy of ¹ μJ to 10 ² μJ. It is preferable to be inside.

The repetition rate is as follows. Pulsed laser means that the laser beam oscillates in a pulse shape, and the repetition rate means the oscillation repetition degree of the laser beam. It is well known that the shape and quality of the object to be processed after processing vary depending on the repetition rate. As a result of various experiments performed by each applicant on each layer constituting the actual active organic light emitting device (which will be described in more detail in the following embodiments), it is preferable that the repetition rate of the ultra-short pulse laser is in the range of 1 Hz to 1 MHz Do.

I will explain the investigation time as follows. The irradiation time means a time when the oscillated laser beam is irradiated to the target point, that is, the time when the laser beam is actually processed with respect to the object to be processed. As a result of various experiments on each layer constituting the actual active organic light emitting device of the present applicant (which will be described in more detail in the following embodiments), the ultrasmall pulse laser has an irradiation time ranging from 1 ns to 10 ² s It is preferable that it is mine.

Next, the processing step will be described. In the processing step, the ultra short pulse laser having the determined processing conditions is irradiated to the processing target portion of the defective pixel of the active organic self-light emitting device, and the actual processing is performed.

At this time, as described above, there are various kinds of defects such as foreign material mixing defects, short defects, and open defects, and conditions such as where defects occur in a composite layer in which several layers are stacked are varied. Accordingly, the processing step may be performed by removing some of the layers forming the active organic self-light emitting device with respect to the processing target site, and repairing the active organic light emitting device with respect to the processing target site. The hole may be formed by removing all of the layers forming the self-light emitting device.

The femtosecond laser processing made in this manner can realize non-thermal processing in which problems such as thermal damage or microcracks due to shock waves are fundamentally eliminated. In addition, unnecessary damage to a part which is basically a non-contact type process and which does not require machining can be minimized in using a laser.

In addition, as described above, the physical and morphological characteristics of each layer forming the active organic self-light emitting device are first identified, and processing is performed by appropriately setting processing conditions such as laser characteristics. Since the processing is performed by a laser, it is possible to process the inside of a transparent or opaque material, that is, selective processing is possible. In other words, it is possible to process only a specific position not only in two dimensions but also in three dimensions. This selective processing is possible because the processing is performed after preparing the characteristic of each layer in advance, as described above, and therefore the processing is not limited depending on what the layer material is. In other words, this method results in material-independent processing.

Hereinafter, an embodiment of a preparation step for determining processing conditions in femtosecond laser processing will be described. The basic ranges of processing conditions and target performance used in this embodiment are as follows.

Femtosecond Laser Processing Condition Range

Pulse width: 90 fs to 800 fs

Wavelength: 265nm to 1552nm (265, 310, 343, 388, 515, 517, 776, 795, 1027, 1035, 1552nm)

Pulse energy: 10 uJ to 80 uJ

Repetition rate: 1 kHz to 400 kHz (optional variable)

Investigation time: 1 ns to 90000 ms

Z axis position: 0.5 mm to 200 mm

Lens: × 5 ~ × 100 (DUV, UV, NUV, NIR lens)

Slit size: 1 m x 1 m to 50 m x 50 m

Femtosecond Laser Target Performance

Processing resolution: 10nm ~ 3μm (non-thermal, optional)

Line width: 500nm ~ 50μm

The active organic light emitting device is composed of layers made of various materials as shown in FIG. These layers include a metal layer forming an electrode such as a glass, a cathode or an anode forming a substrate, an organic layer for each color R, G and B, A planarization layer, a protection layer, and the like.

As described above, the thresholds were determined for each layer through various experiments as follows. As a result of experiments, the threshold value of the laser beam for each layer is as follows: Glass> Protection layer> Planarization layer> Metal (Cathode [Li / Al] = Anode [ITO]) Metal (Source [Cr] > Plastic> Organic (R)> Organic (B)> Organic (G). 10 is a graph of femtosecond laser repair thresholds (expressed in peak intensity) for a single layer, and FIGS. 11A to 11i are ablations in a depth direction according to a change in intensity and the number of pulses based on a femtosecond laser threshold for a single layer. It is a graph showing the ablation rate.

Single layer femtosecond laser repair threshold (expressed as peak intensity)

Glass> 1 × 10 ¹² W / cm ²

Metal (Cathode [Li / Al] = Anode [ITO])> 5 x 10 ¹⁰ W / cm ²

Metal (Source [Cr]) > 4 x 10 ¹⁰ W / cm ²

Metal (Drain [Cr]) > 3.5 x 10 ¹⁰ W / cm ²

Organic (R) > 9 x 10 ⁹ W / cm ²

Organic (G) > 7 x 10 ⁹ W / cm ²

Organic (B) > 6 x 10 ⁹ W / cm ²

Planarization layer> 6 × 10 ¹⁰ W / cm ²

Protection layer  > 7 × 10 ¹¹ W / cm ²

The processing conditions are determined according to the layer characteristics thus identified as follows.

Single Layer Femtosecond Laser Repair Processing Conditions (Laser Wavelength, Pulse Width Only)

Glass: laser wavelength (388 nm), pulse width (100 fs)

Metal: laser wavelength (776 nm), pulse width (800 fs)

Organic (R): laser wavelength (795 nm), pulse width (400 fs)

Organic (G): Laser wavelength (513 nm), pulse width (400 fs)

Organic (B): laser wavelength (395 nm), pulse width (400 fs)

Planarization layer: laser wavelength (1025 nm), pulse width (400 fs)

Protection layer: Laser wavelength (395nm), pulse width (400fs)

Based on the processing conditions determined as above, a condition for repair of a defective part is found and an appropriate repair is performed. For example, the repair establishes and proceeds with a process starting with finding a condition such as selecting a wavelength having an absorbance that does not affect the surrounding layer of a specific layer. As another example, in the case of hole processing, several layers must be processed, so the femtosecond laser beam is actually irradiated while considering conditions such as a high absorption band of each layer, a minimum laser irradiation time, and a minimum pulse width. Considering the conditions in the process, such as irradiation time to select the conditions that can minimize damage to the periphery of the object to be processed.

In this way, ultra-precision, specific heat, and material-independent processing using a femtosecond laser can be realized, and therefore, a repair of an active organic self-light emitting device having high thermal sensitivity and requiring ultra-fine processing can be performed well.

It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims. It goes without saying that various modifications can be made.

100: repair device 110: laser light source
111a to c: unit laser light source 112: selection unit
112a: mirror 112b: shutter
120: lens unit 130: stage
140: photographing unit 150: control unit
160:
500: object to be processed

Claims (7)

An apparatus 100 for repairing defective pixels of an active matrix organic light emitting diode (AMOLED) that is an object to be processed (500),
A selection unit for selecting one of unit laser light sources 111a, 111b, 111c having at least two different pulse widths, and laser light generated by the unit laser light sources 111a, 111b, 111c; A laser light source 110 comprising 112;
A lens unit 120 for irradiating the laser generated by the laser light source 110 to a part to be processed of the object to be processed 500;
A stage 130 on which the processing object 500 is placed, the stage 130 being movable in three X, Y, and Z axis directions relative to the lens unit 120;
A photographing unit 140 photographing a part to be processed of the object 500 to obtain image information;
A controller 150 for controlling three-axis movement of the lens unit 120 or the stage 130 using the image information acquired by the photographing unit 140;
Thermal and non-thermal complex repair device of an active organic self-light emitting device comprising a.
The method of claim 1, wherein the selector 112
At least two mirrors 112a for adjusting and integrating the optical paths of the laser light generated by the unit laser light sources 111a, 111b, and 111c, and the shutters disposed on the optical paths of the integrated laser light. A thermal and non-thermal complex repair device for an active organic self-light emitting device, comprising (112b).
The method of claim 1, wherein the repair apparatus 100
A slit part 160 disposed on the optical path of the laser generated by the laser light source 110 so as to adjust the laser beam size to form a slit for passing only a part of the laser;
Thermal and non-thermal complex repair device of an active organic self-light emitting device, characterized in that further comprises.
The method of claim 3, wherein the slit 160
At least one slit having a different size or shape is formed in a form spaced apart from each other thermal and non-thermal composite repair device of an active organic self-light emitting device.
The method of claim 3, wherein the slit 160
Thermal and non-thermal complex repair device of an active organic self-light emitting device, characterized in that the movement is formed by the control unit (150).
The method of claim 1, wherein the repair apparatus 100
The laser light source 110, the lens unit 120 and the photographing unit 150 is modularized and provided in one gantry (gantry), characterized in that formed by the control unit 150 to be moved together Thermal and non-thermal complex repair device of an active organic self-light emitting device.
The method of claim 3, wherein the repair apparatus 100
The laser light source 110, the lens unit 120, the photographing unit 150, and the slit unit 160 are modularized and provided in one gantry, and are movable together by the control unit 150. Thermal and non-thermal composite repair device of an active organic self-light emitting device, characterized in that formed.

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