KR20030095580A - Apparatus and method for aligning a substrate - Google Patents

Abstract

PURPOSE: An apparatus and a method for aligning a substrate are provided to prevent a drooping phenomenon of the substrate by using a projection portion. CONSTITUTION: An apparatus for aligning a substrate includes one or more support tables(110), a support member(120), and a substrate pressing member(140). The support table(110) includes a substrate support portion(111) and a projection portion. The substrate support portion(111) supports edges of a substrate(11). The projection portion is projected from a part of end portions of the substrate support portion(111). The support member(120) is located on the support table(110) in order to be moved to the vertical direction or the horizontal direction. The substrate pressing member(140) is supported by the support member(120). The substrate pressing member(140) is used for pressing the edges of the substrate(11) and fixing the substrate(11).

Description

Substrate Alignment Device and Substrate Alignment Method {Apparatus and method for aligning a substrate}

The present invention relates to a substrate alignment apparatus and a substrate alignment method, and more particularly, to a substrate alignment apparatus and a substrate alignment method for reducing the deflection of the substrate.

EL devices are attracting attention as next-generation display devices because they have the advantages of wide viewing angle, excellent contrast and fast response speed as spontaneous light emitting display devices. EL devices are classified into inorganic EL devices and organic EL devices according to materials for forming an emitter layer, and organic EL devices have advantages of excellent luminance, driving voltage, and response speed, and multi-coloration, compared to inorganic EL devices. Have.

1 is a cross-sectional view showing the structure of a general organic EL device. Referring to this, the positive electrode layer 12 having a predetermined pattern is formed on the substrate 11. The hole transport layer 13, the light emitting layer 14, and the electron transport layer 15 are sequentially formed on the positive electrode layer 12, and the negative electrode layer 16 is formed on the upper surface of the electron transport layer 15. Here, the hole transport layer 13, the light emitting layer 14, and the electron transport layer 15 are organic thin films made of an organic compound.

The organic EL element having the structure as described above is driven as follows. When a voltage is applied between the selected positive electrode layer 12 and the negative electrode layer 16, holes injected from the selected positive electrode layer 12 are moved to the light emitting layer 14 via the hole transport layer 13. On the other hand, electrons are injected from the negative electrode layer 16 via the electron transport layer 15 to the light emitting layer 14, and carriers are recombined in the light emitting layer 14 region to generate excitons. This exciton is changed from an excited state to a ground state, whereby an image is formed by the fluorescent molecules of the light emitting layer emitting light.

The organic EL device constructed and operated as described above deposits the above-described electrode layer and the organic thin film layer for each pixel on the upper surface of the substrate by using a metal deposition mask in order to realize three colors of red, blue, and green colors during fabrication. Doing.

As described above, in depositing each organic thin film layer on a substrate, it is important to deposit the organic thin film layer at an accurate position by aligning the substrate and the mask accurately. 2 and 3 illustrate an upper housing 30, a mask 20, a substrate support assembly 40, a camera 50, and a conventional substrate aligning device 60. Same as

The upper housing 30 is connected to an upper wall 31 formed of a transparent flat plate, a side wall 32 connected to an end of the upper wall and having a side wall opening 33, and an end wall of the side wall. And a lower wall 34 supporting the support part 35. Under the upper housing 30, there is provided a lower housing (not shown) provided with a crucible capable of heating and subliming organic matter.

The mask 20 is fixed to the mask supporter 35 by the fixing member 21, and the sublimed organic material is deposited on the substrate 11 through a hole formed in the mask 20.

The substrate support assembly 40 includes a magnetic member 42 for applying a magnetic force to the mask 20 during deposition to prevent or mitigate sagging of the mask 20, and the magnetic member 42 directly with the substrate. A scratch preventing member 43 for preventing the substrate from being scratched by contact, a fastening member 44 for fixing the scratch preventing member 43 to the magnetic member 42, and a support rod for supporting the magnetic member in a liftable manner. (41).

The conventional substrate aligning device 60 includes a support table 61 having a substrate support 62 that can support the edge of the substrate, and a support table 61 that can be moved in the vertical and horizontal directions, and a support provided on the support table. And a support member 64 that can be elevated by the member lift actuator 63, and a substrate fixing pin 65 supported by the support member to fix the substrate by pressing an edge of the substrate.

The camera 50 is for checking the alignment between the alignment mark of the substrate displayed on the substrate and the alignment mark of the mask displayed on the mask 20. The marks can be aligned by moving the substrate aligning device horizontally after confirming the alignment state captured by the substrate. Since the substrate is for making an image display device, the marks are generally located at the edge of the substrate, and typically one of the two marks has a solid cross shape and the other mark has a hollow cross shape.

However, in the substrate aligning device 60, the substrate 11 is fixed only by the substrate fixing pin 65 and the flat substrate support 62, so that in the case of the substrate 11 having a predetermined size or more, The deflection distance h (e.g. 1 mm) becomes quite large. This deflection may distort the image of the marks captured by the camera, making it difficult to align the marks, or the deflection distance of which the depth of focus of the camera (eg 300 μm; focuses on the camera's focus). It is a distance having a predetermined width up and down, which is a distance that can be clearly recognized visually, the depth distance may be greater than the vapor deposition apparatus, the apparatus accompanying it, or other circumstances. In order to align the marks while the substrate is not scratched by the mask 20 when the deflection distance is greater than the depth of field of the camera as described above, the substrate 11 and the substrate support assembly 40 are lowered as shown in FIG. 3. After confirming the alignment of the marks with the camera 50 in the state, the substrate and the substrate support assembly 40 are raised as shown in FIG. 2 (in the case of the substrate, the deflection distance is increased, for example, about 2 mm). After moving the substrate horizontally by a predetermined direction and distance in the state, the alignment state of the marks is confirmed by the camera 50 while the substrate 11 and the substrate support assembly 40 are lowered as shown in FIG. 3 again. You must repeat the process. The repetition of this process not only incurs an additional cost and unnecessary time, but also has a problem that the mask 20, the substrate, or the organic thin film layer formed on the substrate may be damaged in the process, which should be overcome in the art. It has been recognized as a task to do.

In addition, the substrate fixing pin 65 is not provided with any shock absorber and has a sharp end portion. Thus, when the substrate is fixed, the substrate fixing pin 65 is damaged by pressing the substrate beyond an appropriate strength, or the strength of the substrate fixing pin is weak. There was a problem that failed to fix.

The present invention for solving the above problem is to prevent or mitigate the deflection of the substrate, while the substrate and the substrate support assembly in the lowered state while the camera visually recognizes the alignment state of the substrate alignment mark and the mask alignment mark to the substrate An object of the present invention is to provide a substrate aligning apparatus and a substrate aligning method which can be moved horizontally so as not to be scratched by the mask 20.

Moreover, an object of this invention is to provide the board | substrate sorting apparatus which can reliably fix a board | substrate, without damaging a board | substrate.

1 is a cross-sectional view showing one cross section of an organic EL element,

2 is a cross-sectional view showing one operation state of a conventional substrate alignment apparatus;

3 is a cross-sectional view showing another operating state of a conventional substrate alignment apparatus;

4 is a cross-sectional view showing an operating state of a substrate alignment apparatus according to the present invention;

FIG. 5 is a partially enlarged perspective view of a portion indicated as V of FIG. 4,

6 is a cross-sectional view taken along the line VI-VI of FIG. 4,

7 is a cross-sectional view showing a substrate supporting portion and a substrate pressing member not having protrusions;

Fig. 8 is a sectional view showing a substrate supporting portion having a protrusion and a substrate pressing member.

Explanation of symbols on the main parts of the drawings

11: substrate 20: mask

30: upper housing 31: upper wall

33: side wall opening 40: substrate support assembly

50: camera 100: substrate alignment device

110: support table 111: substrate support

112: protrusion 120: support member

130: support member actuator 140: substrate pressure member

144: spring 145: substrate contact

The present invention to achieve the above object is:

At least one support table having a substrate support portion capable of supporting an edge of the substrate and a protrusion formed upwardly at at least part of an end portion of the substrate support portion, and movable in vertical and horizontal directions;

A support member positioned on the support table and movable in vertical and horizontal directions; And

A substrate pressing member which is supported by the supporting member and which presses an edge of the substrate adjacent to the rear of the protrusion to fix the substrate and apply a moment to the edge of the substrate in a reverse direction of the substrate deflection. Provide an alignment device.

Preferably, the protrusion is formed at a position on a support table corresponding to four corners of the rectangular substrate. The substrate pressing member preferably includes a pressure rod, a pressure rod casing, and a spring provided between the pressure rod and the pressure rod casing.

In addition, the present invention to achieve the above object is:

A substrate lowering step of lowering the substrate alignment device on which the substrate is fixed so that the distance between the substrate on which the substrate alignment mark is displayed and the mask on which the mask alignment mark is displayed is within the depth of field of the camera; And

And a substrate alignment step of horizontally moving the substrate alignment apparatus so that the image of the substrate alignment mark and the image of the mask alignment mark simultaneously captured by the camera are aligned while the substrate is lowered as described above. to provide. Before the substrate lowering step, it is preferable to further include a substrate fixing step of fixing the substrate between the substrate support and the substrate pressing member by lowering the support member.

The present invention is designed around the substrate aligning apparatus and substrate aligning method that can be used in the organic EL deposition process or its preparation step, but is not limited thereto.

Next, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same reference numerals are used for components having a configuration similar to the conventional components.

4 illustrates a substrate alignment apparatus 100, an upper housing 30, a mask 20, a substrate support assembly 40, a camera 50, and the like, which will be described in detail as follows. .

The upper housing 30 includes an upper wall 31 formed of a transparent flat plate, a side wall 32 connected to an end of the upper wall and having a side wall opening 33, and an end portion of the side wall and connected to a mask support 35. And supporting bottom wall 34. The upper wall is formed of a transparent flat plate to visually recognize the alignment marks of the substrate 11 and the mask 20 as the camera 50. In addition, the side wall opening 33 is formed in the side wall 32 because an actuator for moving the substrate alignment apparatus 100 supporting the substrate in the housing vertically or horizontally is located outside the housing, and the actuator is If installed in the housing, the sidewall opening may not be formed. Below the upper housing 30, a lower housing 160 having a crucible 170 capable of heating and subliming the organic material 180 is provided therein. The interior of the upper housing 30 and the lower housing 160 is maintained in a vacuum by the need of the deposition process.

The mask 20 has holes formed in a predetermined pattern, and the organic material 180 passes through these holes and is deposited on the substrate 11. The mask 20 is fixed to the mask support 35, and in FIG. 4, the mask 20 is fixed to the mask support 35 using a screw.

The substrate support assembly 40 includes a magnetic member 42, a scratch preventing member 43, a fastening member 44, and a support rod 41. The magnetic member 42 prevents or mitigates the deflection of the mask by applying a magnetic force to the mask 20 during deposition, and the scratch preventing member 43 indicates that the magnetic member 42 is in direct contact with the substrate to scratch the substrate. The fastening member 44 fixes the scratch preventing member 43 to the magnetic member 42, and the support rod 41 supports the magnetic member in a liftable manner.

The camera 50 is for confirming the alignment state between the substrate alignment mark displayed on the substrate and the mask alignment mark displayed on the mask, and the user checks the alignment state captured by the camera. The marks can be aligned by moving the horizontally. The user may manually move the substrate alignment apparatus 100 while looking at the alignment marks captured by the camera, and reduce or eliminate the deviation between the recognized marks by using a computer program that can recognize the marks. It is also possible to automatically move the substrate alignment apparatus 100 so as to.

The substrate aligning apparatus 100 includes a support table 110, a support member 120, and a substrate pressurizing member 140. FIG. 5 is an enlarged perspective view of the portion indicated as V in FIG. 4, and shows the support table 110, the support member 120, and the substrate pressing member 140, respectively. 6 is a cross-sectional view taken along the line VI-VI of FIG. 4, and shows the support table 110, the substrate contact portion 145, the substrate 11, and the like, which are part of the substrate pressing member 140.

The support table 110 includes a substrate support 111 capable of supporting an edge of the substrate 11 and a protrusion 112 formed upwardly on at least a portion of an end portion of the substrate support, and an actuator (not shown). It can be moved in the vertical and horizontal directions. If necessary, the protrusion 112 may be formed only at a position on the support table 110 corresponding to four corners of the quadrangular substrate, as shown in FIG. 6, or at both ends of the support table 110. It may be. In addition, although FIG. 6 illustrates that the substrate support part 111 is formed on one support table 110, the substrate support part 111 is not limited thereto, and supports one side of the substrate and the other side of the substrate including a substrate support part supporting one side of the substrate. The support table may be divided into other support tables including a substrate support, or four support tables supporting four vertex portions of the rectangular substrate may be separately configured. When there are two or more support tables 110 as described above, the substrate may be stretched by moving the support tables 110 little by little to reduce the deflection distance of the substrate. However, this is limited according to the tensile strength of the substrate. .

The support member 120 may be positioned above the support table 110 and moved in the vertical and horizontal directions. 4 shows that the support member 120 is lifted by the support member actuator 130 installed on the support table 110. In this case, an actuator for enabling movement in the horizontal direction is not necessarily required. On the other hand, unlike shown in Figure 4, the support member actuator may not be installed in the support table (110). The substrate pressing member 140 presses or releases the pressure of the substrate 11 together with the lifting and lowering of the supporting member 120 by the supporting member actuator 130.

The substrate pressing member 140 is supported by the supporting member 120 and presses the edge of the substrate adjacent to the rear of the protrusion 112 to fix the substrate and prevent the substrate from sagging at the edge of the substrate. The moment can be applied in the reverse direction. As shown in FIGS. 7 and 8, the substrate pressing member 140 is provided between a pressing rod 142, a pressing rod casing 141, and a washer 143 supported by the pressing rod and the pressing rod casing. It is preferable to include a spring 144, a flat substrate contact portion 145. The substrate pressing member 140 is useful not only in the substrate support 111 in which the protrusion 112 is formed, but also in pressing the substrate in the substrate support 111 in which the protrusion 112 is not formed. The spring 144 is compressed when the substrate is fixed by the substrate pressing member 140, and the substrate 144 is adjusted by adjusting a gap between the supporting member 120 and the supporting table 110 for supporting the substrate pressing member 140. You can set the strength to fix the.

Hereinafter, a substrate alignment method according to the present invention will be described.

The substrate alignment method includes a substrate lowering step and a substrate alignment step. The substrate lowering step is a step of lowering the substrate alignment apparatus 100 to which the substrate is fixed so that the distance between the substrate on which the substrate alignment mark is displayed and the mask on which the mask alignment mark is displayed is within the depth of field of the camera. The depth of distance is mainly affected by the distance between the camera and the substrate, for example, about 300 μm. The substrate aligning step includes moving the substrate aligning device 100 horizontally such that the image of the substrate alignment mark and the image of the mask alignment mark are simultaneously captured by the camera while the substrate is lowered as described above. The substrate aligning apparatus 100 may be moved by actuators (not shown) that are commonly used. There may be a substrate fixing step of fixing the substrate before the substrate lowering step. In the substrate fixing step, the supporting member 120 is lowered to press the substrate supported by the substrate supporting member 111. Thus, the substrate is fixed between the substrate support 111 and the substrate pressing member 140. The strength of the pressing is determined according to the degree to which the spring 144 of the substrate pressing member 140 is compressed.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary, and those skilled in the art will understand that various modifications and equivalent other embodiments are possible therefrom. Therefore, the true technical protection scope of the present invention will be defined by the technical spirit of the appended claims.

The protrusion 112 provided in the support table 110 of the present invention can apply a moment in the reverse direction of the deflection direction of the substrate, thereby preventing or mitigating the substrate, and thus lowering the substrate and the substrate support assembly. Provided is a substrate alignment apparatus 100 and a substrate alignment method capable of horizontally moving the substrate so as not to be scratched by the mask while visually recognizing the alignment of the substrate alignment mark and the mask alignment mark with a camera.

In addition, the substrate pressurizing member 140 of the present invention includes a substrate contacting portion having a flat surface and a spring capable of buffering up and down, so that the substrate can be reliably fixed at an appropriate strength without damaging the substrate. A substrate aligning device 100 is provided.

Claims (5)

At least one support table having a substrate support portion capable of supporting an edge of the substrate and a protrusion formed upwardly at at least part of an end portion of the substrate support portion, and movable in vertical and horizontal directions; A support member positioned on the support table and movable in vertical and horizontal directions; And A substrate pressing member which is supported by the supporting member and which presses an edge of the substrate adjacent to the rear of the protrusion to fix the substrate and apply a moment to the edge of the substrate in a reverse direction of the substrate deflection. Alignment device. The method of claim 1, And the protrusion is formed at a position on a support table corresponding to four corners of a rectangular substrate. The method according to claim 1 or 2, And the substrate pressing member includes a pressing rod, a pressing rod casing, and a spring provided between the pressing rod and the pressing rod casing. A substrate lowering step of lowering the substrate alignment device on which the substrate is fixed so that the distance between the substrate on which the substrate alignment mark is displayed and the mask on which the mask alignment mark is displayed is within the depth of field of the camera; And And a substrate alignment step of horizontally moving the substrate alignment apparatus so that the image of the substrate alignment mark and the image of the mask alignment mark simultaneously captured by the camera are aligned while the substrate is lowered. The method of claim 4, wherein And a substrate fixing step of fixing the substrate between the substrate support and the substrate pressing member by lowering the support member before the substrate lowering step.