KR20150005022A - Apparatus for inspecting thickness of material layer formed on substrate - Google Patents

Abstract

An apparatus for inspecting the thickness of a layer of material formed on a substrate, the apparatus comprising: an inspection chamber for performing a thickness inspection on a layer of material formed on the substrate; A substrate stage for supporting the substrate so as to face downward, and an elliptic system disposed below the substrate stage for measuring the thickness of the material layer. At this time, the substrate is transferred into the inspection chamber by a substrate transfer robot disposed outside the inspection chamber, and a substrate transfer unit for transferring the substrate between the substrate stage and the substrate transfer robot is provided in the inspection chamber Respectively.

Description

[0001] Apparatus for inspecting thickness of a material layer formed on a substrate [0002]

Embodiments of the present invention are directed to an apparatus for testing the thickness of a layer of material formed on a substrate. To an apparatus for inspecting thicknesses of material layers formed on a mother substrate (hereinafter referred to as a substrate) to manufacture display cells such as OLED (Organic Light Emitting Device) cells .

The OLED device used as a flat panel display device is widely used in portable display devices, smart phones, tablet PCs, and the like, as well as being widely used as a next-generation display device due to its large size, having a wide viewing angle, excellent contrast and high response speed . In particular, the OLED device has advantages such as brightness, driving voltage, response speed, etc., and is capable of multi-coloring as compared with an inorganic light emitting display device.

In the manufacturing process of the OLED device, a TFT (Thin Film Transistor) layer is formed on the substrate through various film forming processes and etching processes, and an organic light emitting layer including a lower electrode layer, an organic material layer and an upper electrode layer is formed on the TFT layer . Then, the OLED device can be completed by sealing the TFT layer and the substrate on which the organic light emitting layer is formed using an encapsulating substrate. At this time, the organic layer may include an electron transport layer, a light emitting layer, and a hole transport layer.

In addition, a plurality of OLED cells may be formed on the substrate. After the sealing process is completed, the OLED device may be completed by individualizing each OLED cell through a cutting process.

Meanwhile, after the sealing process is completed, an inspection process for OLED cells formed on the substrate may be performed. In the inspection process, a function test of the TFT layer, a correction circuit inspection, an image quality inspection, a spectral inspection, an image inspection, and the like may be performed by applying an inspection signal to the OLED cells. However, since the inspecting process is performed after the sealing process is completed as described above, the loss due to the defective OLED devices in the inspecting process may be increased.

In order to solve the above problems, Japanese Unexamined Patent Application Publication No. 10-2006-0017586 discloses a method of performing the TFT array function test before performing the cell process after the TFT array forming process, -0046645 and 10-2011-0096382 disclose a method for measuring the thickness of the thin film layers during or after forming each thin film layer of OLED cells.

Meanwhile, when the substrate is transferred from the deposition equipment for forming the material layers such as the lower electrode layer, the organic film layer and the upper electrode layer on the substrate to the inspection chamber for inspecting the thickness of the material layers, It can be transported with the front face down. When the front surface of the substrate faces downward as described above, substrate handling may be required such as reversing the substrate to check the thickness of the material layers.

Inversion of the substrate may require a separate inversion device, thereby increasing the manufacturing cost and size, etc., of the device for performing the thickness inspection of the material layers on the substrate. In addition, the time required for inspecting the material layer thickness of the substrate may be increased, and the substrate may be damaged in the reversal operation of the substrate.

Embodiments of the present invention provide an apparatus capable of performing a thickness inspection of material layers on a substrate without reversing the substrate when the front surface of the substrate on which the material layers for manufacturing display cells are formed faces downward have.

According to an aspect of the present invention, there is provided an apparatus for inspecting a thickness of a material layer on a substrate. The apparatus includes a test chamber for inspecting a thickness of a material layer formed on a substrate, A substrate stage for supporting the substrate such that the front surface of the material layer is facing downward and an elliptic system disposed below the substrate stage for measuring the thickness of the material layer. At this time, the substrate may be transferred into the inspection chamber by a substrate transfer robot disposed outside the inspection chamber, and a substrate transfer path for transferring the substrate between the substrate stage and the substrate transfer robot may be provided in the inspection chamber. Unit may be provided.

According to embodiments of the present invention, the substrate transfer unit may include a plurality of support members for supporting the substrate and a vertical driver for moving the support members in the vertical direction.

According to embodiments of the present invention, the substrate transfer unit may further include a buffer cassette for temporary storage of the substrate, the support members may be disposed on the buffer cassette, And the buffer cassette and the support members can be moved in the vertical direction.

According to embodiments of the present invention, a sheet resistance measuring unit for measuring a sheet resistance of the material layer may be disposed on one side of the elliptic system.

According to embodiments of the present invention, the substrate stage may be provided with a plurality of vacuum holes for sucking the substrate and a plurality of clamps for gripping edge portions of the substrate.

According to embodiments of the present invention, the substrate stage may include a vacuum plate formed with the vacuum holes, and the clamps may be disposed at the edge portions of the vacuum plate.

According to embodiments of the present invention, a stage driving unit for moving and rotating the vacuum plate in the vertical and horizontal directions may further be provided.

According to embodiments of the present invention, it is possible to further include clamp actuators for actuating the clamps, wherein the clamp actuators are arranged to grip the edge portions of the substrate when the internal pressure of the vacuum holes becomes higher than a predetermined pressure, Clamps can be operated.

According to embodiments of the present invention, the vacuum holes may be connected to a vacuum system including a vacuum pump. When the internal pressure of the vacuum holes becomes higher than a predetermined pressure due to an operation error of the vacuum system or a vacuum leak, An auxiliary vacuum system may be further provided to provide vacuum pressure for adsorbing the substrate.

According to the embodiments of the present invention, it is possible to further include a gas supplier for supplying an inert gas to the inspection chamber, and a pressure control valve for discharging the inert gas supplied to the inspection chamber.

According to the embodiments of the present invention, a safety valve may be further provided for discharging the inert gas from the inspection chamber when the internal pressure of the inspection chamber becomes abnormally high.

According to embodiments of the present invention, a circulation pipe and a fan filter unit for circulating the inert gas supplied to the inspection chamber may be further provided.

According to embodiments of the present invention as described above, when a substrate is provided such that the front surface of the material layer is facing downward, the thickness inspection process for the material layer can be performed without inverting the substrate. Particularly, the substrate can be vacuum-adsorbed to the lower surface of the substrate stage, and thickness inspection of the material layer can be performed by an elliptic system disposed under the substrate stage.

Therefore, since the substrate is not required to be inverted for inspecting the thickness of the material layer, a separate inversion device or the like is unnecessary, so that the manufacturing cost of the thickness inspection apparatus and the time required for the thickness inspection can be greatly reduced.

In addition, even when the internal pressure of the vacuum holes provided on the lower surface of the substrate stage for adsorbing the substrate is changed due to an operational error of the vacuum system, vacuum leakage or the like, a plurality of clamps are arranged on the substrate stage, By gripping the portions, it is possible to prevent the substrate from dropping and to stably maintain the substrate. In particular, when an operation error occurs in the vacuum system, the vacuum adsorption state of the substrate can be maintained more stably by operating the auxiliary vacuum system connected to the vacuum holes.

1 is a schematic diagram for explaining OLED cells formed on a substrate.
2 is a schematic block diagram illustrating an inline process facility to which an apparatus for testing a material layer thickness on a substrate is connected, in accordance with an embodiment of the present invention.
3 is a schematic diagram illustrating an apparatus for testing the thickness of a material layer formed on a substrate according to an embodiment of the present invention.
Fig. 4 is a schematic plan view for explaining the substrate transfer unit shown in Fig. 3. Fig.
Fig. 5 is a schematic side view for explaining the substrate transfer unit shown in Fig. 3. Fig.
Fig. 6 is a schematic plan view for explaining the substrate stage shown in Fig. 3. Fig.
FIG. 7 is a schematic side view for explaining the substrate stage and the ellipsometer shown in FIG. 3. FIG.
Fig. 8 is a schematic view for explaining the operation of the substrate stage shown in Fig. 3; Fig.

BRIEF DESCRIPTION OF THE DRAWINGS The invention will be described in more detail below with reference to the accompanying drawings showing embodiments of the invention. However, the present invention should not be construed as limited to the embodiments described below, but may be embodied in various other forms. The following examples are provided so that those skilled in the art can fully understand the scope of the present invention, rather than being provided so as to enable the present invention to be fully completed.

When an element is described as being placed on or connected to another element or layer, the element may be directly disposed or connected to the other element, and other elements or layers may be placed therebetween It is possible. Alternatively, if one element is described as being placed directly on or connected to another element, there can be no other element between them. The terms first, second, third, etc. may be used to describe various items such as various elements, compositions, regions, layers and / or portions, but the items are not limited by these terms .

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. Furthermore, all terms including technical and scientific terms have the same meaning as will be understood by those skilled in the art having ordinary skill in the art, unless otherwise specified. These terms, such as those defined in conventional dictionaries, shall be construed to have meanings consistent with their meanings in the context of the related art and the description of the present invention, and are to be interpreted as being ideally or externally grossly intuitive It will not be interpreted.

Embodiments of the present invention are described with reference to schematic illustrations of ideal embodiments of the present invention. Thus, changes from the shapes of the illustrations, e.g., changes in manufacturing methods and / or tolerances, are those that can be reasonably expected. Accordingly, the embodiments of the present invention should not be construed as being limited to the specific shapes of the areas illustrated in the drawings, but include deviations in the shapes, the areas described in the drawings being entirely schematic and their shapes Is not intended to illustrate the exact shape of the area and is not intended to limit the scope of the invention.

FIG. 1 is a schematic structural view for explaining OLED cells formed on a substrate, and FIG. 2 is a schematic view for explaining an inline processing equipment to which an apparatus for checking a material layer thickness on a substrate is connected according to an embodiment of the present invention FIG. 3 is a schematic diagram for explaining an apparatus for checking the thickness of a material layer formed on the substrate shown in FIG. 2. FIG.

1 to 3, an apparatus 100 for testing the thickness of a layer of material formed on a substrate 10 according to an embodiment of the present invention includes a substrate 100 for fabricating display cells, such as OLED cells 20, May be used to check the thickness of the material layers that make up the display cells in the process.

Specifically, the thickness inspection apparatus 100 may include a cell process for forming a plurality of OLED cells 20 on the substrate 10 in the manufacturing process of the OLED cells 20 and a cell process for forming the OLED cells 20 using the encapsulation substrate (not shown) May be used to inspect the thickness of the material layers that make up the OLED cells 20 between the sealing process for sealing the OLED cells 20. Also, the thickness of the material layers may be inspected after forming each of the material layers during the cell process, and repeatedly performed for each of the material layers.

In particular, as shown in FIG. 2, the thickness inspection apparatus 100 according to an embodiment of the present invention may be connected to an in-line process facility for manufacturing the display cells 20. FIG. For example, the thickness inspection apparatus 100 may be connected between the cell processing facility 30 for the cell process and the sealing process facility 40 for the sealing process. For example, the cell processing facility 30 and the sealing process facility 40 may have a cluster shape, and the substrate 10 may be transferred between the cell processing facility 30 and the sealing process facility 40 An in-line substrate transfer device 50 may be disposed.

According to an embodiment of the present invention, the thickness inspection apparatus 100 may be connected to the in-line substrate transfer apparatus 50 between the cell process facility 30 and the sealing process facility 40, Can be used to check the thickness of the material layers formed on the substrate 10 at the substrate 30.

The cell process includes forming a plurality of OLED cells 20 on a substrate 10, forming a TFT array layer on the substrate 10 and forming an organic emission layer on the TFT array layer Lt; / RTI > For example, the organic light emitting layer may include a lower electrode layer, an organic material layer, an upper electrode layer, and the like. In particular, the organic material layer may include an electron transport layer, a light emitting layer, and a hole transport layer. 1, the OLED cells 20 formed on the substrate 10 in the cell process each have a plurality of test pads 22 electrically connected to the TFT array layer .

The sealing process may be performed after the cell process by sealing the OLED cells 20 by bonding the substrate 10 on which the OLED cells 20 are formed and the sealing substrate.

The thickness inspection apparatus 100 according to an embodiment of the present invention can be used to check the thickness of material layers such as a lower electrode layer, an organic material layer, an upper electrode layer, and the like formed on the substrate 10 as described above.

According to an embodiment of the present invention, the thickness inspection apparatus 10 and the inline process facility may be connected by a separate substrate transfer module 300, and the substrate transfer module 300 may be connected to the thickness inspection apparatus 100 ) And the in-line substrate transfer device 50 of the inline process facility.

2, an electrical and optical inspection apparatus 200 may be connected to the substrate transport module 300 to perform an electrical and optical inspection process on the OLED cells 20. The substrate 10 are transferred from the cell processing facility 30 to the electrical and optical inspection apparatus 200 and / or the thickness inspection apparatus 100, and an electrical and optical inspection process and / or a material layer thickness inspection process are performed And then transferred to the sealing process facility 40.

The substrate transfer module 300 includes a substrate transfer chamber connected to the in-line substrate transfer device 50 and the substrate transfer chamber disposed within the substrate transfer chamber, and electrically and optically inspecting the device 200, the thickness inspection device 100, And a substrate transfer robot 310 for transferring the substrate 10 between process equipments.

As an example, a substrate aligning unit for holding and aligning the substrate 10 transferred to the substrate transfer chamber by the inline substrate transfer robot 52 may be disposed in the substrate transfer chamber, The unit can transfer the substrate 10 to the substrate transfer robot 310 after aligning the substrate 10. The substrate transfer robot 310 may transfer the substrate 10 to the electrical and optical inspection apparatus 200 or the deposition apparatus 100. The substrate transfer module 300 is disclosed in detail in Korean Patent Application No. 10-2013-0045802 filed by the present applicant and will not be described further.

However, according to another embodiment of the present invention, the thickness measurement apparatus 100 may be directly connected to the in-line substrate transfer apparatus 50, and the substrate 10 may be connected to the in- Or may be transferred to the thickness measuring apparatus 100 by a substrate transfer robot 52 provided in the apparatus 50.

According to an embodiment of the present invention, the thickness measuring apparatus 100 may include an inspection chamber 102 for performing a thickness inspection process on the material layers, The substrate 10 may be loaded onto a substrate stage 106 disposed within the inspection chamber 102. At this time, the substrate 10 can be transferred to the inspection chamber 102 with the OLED cells 20, that is, the material layers facing downward, and the substrate transfer robot 310 or 52 can transfer the substrate 10 The substrate 10 can be transported while supporting the edge portions of the substrate 10.

A substrate transfer unit 140 for transferring the substrate 10 between the substrate stage 106 and the substrate transfer robot 310 or 52 and a substrate transfer unit 140 for transferring the substrate 10 between the substrate stage 106 and the substrate transfer robot 310 or 52 are provided in the inspection chamber 102, An ellipsometer 130 may be provided to inspect the thickness of the material layers formed on the substrate 10 supported by the substrate 10.

Fig. 4 is a schematic plan view for explaining the substrate transfer unit shown in Fig. 3, and Fig. 5 is a schematic side view for explaining the substrate transfer unit shown in Fig.

4 and 5, the substrate transfer unit 140 includes a plurality of first support members 142 for supporting the substrate 10 and a plurality of second support members 142 for supporting the first support members 142 in a vertical direction And a vertical driving unit 144 for moving the vertical driving unit 144.

According to an embodiment of the present invention, the substrate transfer unit 140 may include a buffer cassette 146 for temporary storage of the substrate 10. At this time, the first support members 142 may be disposed on the buffer cassette 146 as shown, and the vertical drive 144 may be disposed on the lower portion of the buffer cassette 146 . That is, the vertical driving unit 144 can simultaneously move the buffer cassette 146 and the first support members 142 in the vertical direction.

For example, after the substrate 10 is transferred into the inspection chamber 102 by the robot arm of the substrate transfer robot 310, the vertical driving unit 144 drives the first support members 142 So that the substrate 10 can be loaded on the first support members 142. Subsequently, after the robot arm of the substrate transfer robot 310 retracts from the inspection chamber 102, the substrate 10 is lifted up by the first support members 142 or downward of the substrate stage 106 To the lower surface of the substrate stage 106. At this time, the substrate stage 106 can vacuum-adsorb the substrate 10 using a vacuum pressure. The substrate stage 106 will be described later.

The buffer cassette 146 may be used to temporarily store the substrate 10 or other substrates 10 and the buffer cassettes 146 may be used to temporarily store the substrates 10 A plurality of second support members 148 may be disposed. As shown in the figure, the buffer cassette 146 may be provided with three stages of second support members 148, and the substrates 10 may be mounted on the second support members 148 And can be supported in a multi-layered form.

The vertical driving unit 144 may be constructed using a pneumatic cylinder or a motor, a ball screw, a ball nut, and the like, and a linear motion guide for guiding vertical movement of the buffer cassette 146.

FIG. 6 is a schematic plan view for explaining the substrate stage shown in FIG. 3, FIG. 7 is a schematic side view for explaining the substrate stage and the ellipsometer shown in FIG. 3, and FIG. 8 is a cross- Fig. 3 is a schematic view for explaining the operation of the stage. Fig.

6 to 8, the substrate stage 106 includes a vacuum plate 108 having a plurality of vacuum holes 109 for sucking the backside of the substrate 10, And a stage driving unit 110 for moving and rotating the wafer W.

The substrate 10 may be vacuum adsorbed on the lower surface of the vacuum plate 108 by vacuum pressure provided through the vacuum holes 109. The vacuum holes 109 may be formed in the vacuum system 120, Lt; / RTI > Although not shown in detail, the vacuum system 120 may include a vacuum pump, a pressure control valve, etc., as shown in FIG. 8, and its operation may be controlled by the controller 104 (see FIG. 3) have.

The stage driving unit 110 may have a substantially rectangular coordinate robot shape. The stage driving unit 110 includes horizontal driving units 112 and 114 for moving the vacuum plate 108 in the horizontal direction, a vertical driving unit 116 for moving the vacuum plate 108 in the vertical direction, And a rotation drive unit 118 for rotating the vacuum plate 108.

The horizontal driving units 112 and 114 are disposed between the load and unload areas of the substrate 10 and the upper area of the inspection area, i.e., the substrate transfer unit 140, and the upper area of the ellipsometer 130, The vacuum plate 108 can be moved in the horizontal direction and the vacuum plate 108 can be horizontally moved for inspection of the thickness of the material layers in the inspection area. The horizontal driving units 112 and 114 may include an X axis driving unit 112 and a Y axis driving unit 114. The X axis driving unit 112 and the Y axis driving unit 114 may be a linear motor, A motion guide, or the like.

The vertical driving unit 116 may vertically move the vacuum plate 108 to load and unload the substrate 10 and to inspect the thickness of the material layers. For example, the vertical driving unit 116 may be configured using a servo motor, a speed reducer, and a linear motion guide. However, the configurations of the X-axis driving unit 112, the Y-axis driving unit 114, and the vertical driving unit 116 may be variously modified, so that the scope of the present invention is not limited thereto.

The rotation driving unit 118 may rotate the vacuum plate 108 to check the thickness of the material layers. For example, the rotation drive unit 118 may be constructed using a direct drive motor and a cross roller bearing, and a vacuum pipe or the like connected to the vacuum plate 108 through a central through hole of the direct drive motor Can be deployed.

In particular, the X-axis driving part 112, the Y-axis driving part 114, and the rotation driving part 118 are arranged such that a plurality of inspection areas set on the substrate 10 sequentially correspond to the ellipsometer 130, The user can horizontally move and rotate the display unit 108.

The vertical driving unit 116 may be mounted on the X-axis driving unit 112 and the rotary driving unit 118 may be mounted on the lower portion of the vertical driving unit 116. For example, That is, the vertical driving part 116 can be moved in the horizontal direction by the horizontal driving parts 112 and 114, the rotation driving part 118 can be moved in the vertical direction by the vertical driving part 116, The plate 108 may be mounted on the lower portion of the rotation driving portion 118.

According to an embodiment of the present invention, the inspection apparatus 100 includes an auxiliary vacuum system 122 connected to vacuum holes 109 formed in the vacuum plate 108 as shown in FIG. 8 . Although not shown in detail, the auxiliary vacuum system 122 may include an auxiliary vacuum pump, a pressure control valve, and the like. The vacuum system 120 may include a plurality of vacuum holes (not shown) And can provide vacuum pressure through the vacuum holes 108 to stably adsorb the substrate 10 when the pressure is higher than a predetermined pressure.

Although not shown, a pressure sensor (not shown) for measuring the pressure inside the vacuum holes 109 may be mounted on the substrate stage 106, and the controller 104 controls the vacuum holes The operation of the auxiliary vacuum system 122 may be controlled based on the internal pressure of the auxiliary vacuum system 109.

Also, according to an embodiment of the present invention, a plurality of clamps 124 for holding edge portions of the substrate 10 may be disposed at edge portions of the vacuum plate 108. The clamps 124 may be formed to prevent the substrate 10 from falling when the pressure inside the vacuum holes 109 becomes higher than a preset pressure due to an operation error of the vacuum system 120, The edge portions of the substrate 10 can be gripped.

Clamp actuators 126 for actuating the clamps 124 may be disposed on the vacuum plate 108 and the clamps 124 may be rotatably mounted on the vacuum plate 108 It can be mounted on the edge portion. Pneumatic cylinders may be used as the clamp driving parts 126 and the clamp driving parts 126 may rotate the clamps 124 so that the substrate 10 is held by the clamps 124 have.

Alternatively, however, the clamps 124 may be coupled to the clamp drivers 126 to move horizontally, i.e., away from or proximate to the substrate 10, thereby moving the clamps 124 The holding of the substrate 10 may be performed.

The ellipsometer 130 may be disposed below the substrate stage 106 and may be used to measure the thickness of material layers on the substrate 10. The ellipsometer 130 may include a light source 132 that emits light toward the material layer and a photodetector 134 that detects light reflected from the material layer. However, since the type of the ellipsometer 130 can be variously changed, the scope of the present invention is not limited by the configuration of the ellipsometer 130 itself.

According to an embodiment of the present invention, the thickness measuring apparatus 100 may further include a sheet resistance measuring unit 136 for measuring a sheet resistance of the material layers. The sheet resistance measurement unit 136 may be disposed adjacent to the elliptic system 130 and may have probes for measuring the sheet resistance of the material layers though not shown in detail.

On the other hand, the thickness inspection and the sheet resistance measurement of the material layers may be repeatedly performed after forming the respective material layers. Alternatively, the material layer may be selectively performed on the specific material layer, and the scope of the present invention is not limited by the thickness of the material layers and the number or order of sheet resistance measurement.

According to an embodiment of the present invention, the inside of the inspection chamber 102 may be formed of an inert gas, for example, a nitrogen gas atmosphere to prevent the substrate 10 from coming into contact with outside air. The thickness inspection apparatus 100 may include a gas supplier 150 for providing an inert gas into the inspection chamber 102. The operation of the gas supplier 150 may be controlled by the controller 104 Lt; / RTI > Although not shown in detail, the inert gas may be supplied through the upper portion of the inspection chamber 102, and the inert gas supplied to the inspection chamber 102 may be discharged through the lower portion of the inspection chamber 102 have.

The gas supplier 150 may be connected to a gas source 160 for supplying the inert gas and may supply the inert gas to the test chamber 102 according to a control signal from the controller 104 . For example, the gas supplier 150 may be constructed using a valve, a mass flow controller (MFC), or the like.

On the other hand, the oxygen concentration and moisture concentration in the inspection chamber 102 can be controlled very strictly. For example, the oxygen concentration and the moisture concentration in the inspection chamber 102 can be controlled to be about 0.05 ppm to 0.5 ppm, respectively. In particular, as an example, the oxygen concentration and the moisture concentration in the inspection chamber 102 can be managed to be about 0.1 ppm, respectively.

According to an embodiment of the present invention, a nitrogen purge step may be performed to form the inside of the inspection chamber 102 in a nitrogen atmosphere. Nitrogen gas may be supplied from the gas source 160 into the inspection chamber 102 through the gas supplier 150 in the nitrogen purge step for the inspection chamber 102, The nitrogen gas can be exhausted through the pressure control valve 154 connected to the nitrogen gas. The pressure control valve 154 may be opened or closed according to the pressure inside the inspection chamber 102. The nitrogen purge step may be performed when the oxygen concentration and the moisture concentration in the inspection chamber 102 reach a predetermined range Lt; / RTI >

Although not shown in detail, the inspection chamber 102 may include an oxygen sensor and a moisture sensor for measuring the oxygen concentration and the moisture concentration, and the controller 104 controls the oxygen concentration in the inspection chamber 102 And the operation of the gas supplier (150) and the pressure control valve (154) according to the water concentration.

The pressure control valve 154 may be closed by the control unit 104 after the oxygen concentration and the nitrogen concentration in the inspection chamber 102 reach a predetermined range. 3, the thickness inspection apparatus 100 includes a circulation pipe 170 for circulating nitrogen gas supplied to the inspection chamber 102 and an atmosphere control unit (not shown) for circulating the nitrogen gas supplied to the inspection chamber 102. [ 172 and a fan filter unit 174.

The nitrogen gas supplied into the test chamber 102 can be circulated by the fan filter unit 174 and the atmosphere control unit 172 controls the flow rate of the circulated nitrogen gas and includes the nitrogen gas It is possible to remove foreign substances. The atmosphere regulator 172 may be connected to the gas source 160 and may supply the nitrogen gas to the inspection chamber 102 through the fan filter unit 174. [ The atmosphere control unit 172 may discharge a part of the circulated nitrogen gas through the discharge pipe 176 and adjust the supply and discharge flow rate of the nitrogen gas to control the pressure inside the inspection chamber 102 It can be kept constant.

Although not shown, the thickness inspection apparatus 100 may include a pressure sensor (not shown) for measuring the internal pressure of the inspection chamber 102, and the control unit 104 may measure The pressure control valve 154 and the atmospheric control unit 172 according to the detected pressure value.

According to an embodiment of the present invention, the gas supplier 150 may supply the inert gas to the test chamber 102 via the ionizer 152. The ionizer 152 may be used to prevent the substrate 10 from being charged by the supply of the inert gas.

Also, according to an embodiment of the present invention, a safety valve 156 may be connected to the inspection chamber 102. The safety valve 156 may be used to maintain the internal pressure of the inspection chamber 102 constant when the pressure control valve 154 and / or the atmosphere control unit 172 are not operating normally. In particular, the safety valve 156 may be opened when the internal pressure of the inspection chamber 102 rises abnormally, so that the internal pressure of the inspection chamber 102 is stably maintained within a predetermined range .

According to another embodiment of the present invention, the pressure control valve 154 may be connected to a vacuum system (not shown) including a vacuum pump or the like, and the nitrogen gas supplied to the inspection chamber 102 is supplied to the vacuum system It may be forcibly evacuated.

According to the embodiments of the present invention as described above, when the substrate 10 is provided such that the front surface on which the plurality of material layers for manufacturing the OLED cells 20 are formed faces downward, A thickness inspection process for the material layers can be performed. Particularly, the substrate 10 can be vacuum-adsorbed on the lower surface of the substrate stage 106 and the thickness of the material layers can be inspected by the ellipsometer 130 disposed below the substrate stage 106 have.

Therefore, since the substrate 10 is not required to be inverted for inspecting the thickness of the material layers, a separate inverting device or the like is unnecessary, so that the manufacturing cost of the thickness inspection apparatus 100 and the time required for the thickness inspection are large Can be reduced.

Even when the internal pressure of the vacuum holes 109 provided on the lower surface of the substrate stage 106 for absorbing the substrate 10 is changed due to an operation error of the vacuum system 120 or a vacuum leak or the like A plurality of clamps 124 are disposed on the substrate stage 106 to hold the edge portions of the substrate 10 to prevent the substrate 10 from dropping and stably maintain the substrate 10 . In particular, when the operation error of the vacuum system 120 occurs, the vacuum adsorption state of the substrate 10 can be more stably maintained by operating the auxiliary vacuum system 122 connected to the vacuum holes 109.

It will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the spirit or scope of the present invention as defined by the following claims It can be understood that

10: substrate 20: OLED cell
30: Cell process facility 40: Sealing process facility
50: substrate transfer device for in-line 100: thickness inspection device
102: Inspection chamber 104:
106: substrate stage 108: vacuum plate
110: stage driving part 120: vacuum system
122: auxiliary vacuum system 124: clamp
126: Clamp driving part 130:
136: sheet resistance measurement unit 140: substrate transfer unit
142: first support member 144: vertical drive part
146: buffer cassette 148: second support member
150: gas supplier 154: pressure control valve
156: Safety valve 160: Gas source
170: circulation piping 172: atmosphere control unit
174: Fan filter unit

Claims (12)

An inspection chamber for performing a thickness inspection on a layer of material formed on the substrate;
A substrate stage disposed inside the inspection chamber and supporting the substrate such that a front surface of the material layer is downward; And
And an elliptic system disposed below the substrate stage for measuring a thickness of the material layer,
The substrate is transferred into the inspection chamber by a substrate transfer robot disposed outside the inspection chamber and a substrate transfer unit for transferring the substrate between the substrate stage and the substrate transfer robot is provided in the inspection chamber The thickness of the layer of material formed on the substrate. 2. The method of claim 1, wherein the substrate transfer unit comprises a plurality of support members for supporting the substrate and a vertical drive for moving the support members in a vertical direction, . 3. The apparatus of claim 2, wherein the substrate transfer unit further comprises a buffer cassette for temporary storage of the substrate,
Wherein the support members are disposed on the buffer cassette,
Wherein the vertical driver is disposed below the buffer cassette to move the buffer cassette and the support members in a vertical direction. The apparatus of claim 1, further comprising a sheet resistance measurement unit disposed on one side of the elliptic system for measuring a sheet resistance of the material layer. 2. The method according to claim 1, wherein the substrate stage is provided with a plurality of vacuum holes for attracting the substrate and a plurality of clamps for holding edge portions of the substrate, Apparatus for inspection. 6. The apparatus of claim 5, wherein the substrate stage includes a vacuum plate having the vacuum holes formed therein,
Wherein the clamps are disposed at edge portions of the vacuum plate. ≪ RTI ID = 0.0 > 8. ≪ / RTI > 7. The apparatus of claim 6, further comprising a stage driver for moving and rotating the vacuum plate in vertical and horizontal directions. 6. The apparatus of claim 5, further comprising clamp actuators for actuating the clamps,
Wherein the clamp actuators operate the clamps to grasp the edge portions of the substrate when the internal pressure of the vacuum holes becomes higher than a preset pressure. 6. The apparatus of claim 5, wherein the vacuum holes are connected to a vacuum system including a vacuum pump,
Further comprising an auxiliary vacuum system for providing vacuum pressure for adsorbing the substrate when the internal pressure of the vacuum holes becomes higher than a predetermined pressure due to operation error of the vacuum system or vacuum leakage. Apparatus for inspecting the thickness of a material layer. 2. The apparatus of claim 1, further comprising: a gas supplier for supplying an inert gas into the inspection chamber; And
Further comprising a pressure control valve for discharging the inert gas supplied to the inspection chamber. ≪ Desc / Clms Page number 15 > 11. The apparatus of claim 10, further comprising a safety valve for discharging the inert gas from the inspection chamber when the internal pressure of the inspection chamber becomes abnormally high. Device. 11. The apparatus of claim 10, further comprising a circulation line and a fan filter unit for circulating the inert gas supplied to the inspection chamber.

Images