JP2024054824A - Deposition apparatus, detection apparatus, and control method for deposition apparatus - Google Patents

Abstract

To provide a technique for detecting the state of the surface of an electrostatic chuck that attracts and holds a substrate in a deposition apparatus.SOLUTION: A deposition apparatus is used to deposit a film on a substrate, and has an electrostatic chuck having a suction surface to attract a substrate and a detection means to detect the state of the suction surface to which the substrate is not attracted.SELECTED DRAWING: Figure 4

Description

The present invention relates to a film forming apparatus, a detection device, and a method for controlling the film forming apparatus.

In recent years, flat panel display devices such as organic electroluminescence (EL) display devices have been used as display screens for monitors, televisions, smartphones, and the like. The panel of an organic EL display device has a structure in which an organic layer that emits light is formed between two opposing electrodes (a cathode electrode and an anode electrode). When forming an organic EL display panel using a film-forming device, the peripheral edge of the substrate is held by a substrate holder disposed in the chamber of the film-forming device, and an evaporation source disposed at the bottom of the chamber is heated to release a metal or organic evaporation material, which is then evaporated onto the underside of the substrate through a mask. However, as the substrate size increases, the central portion of the substrate is more likely to bend due to its own weight, which may affect the evaporation accuracy.

In order to reduce the bending of the substrate, a technique has been proposed for holding the substrate using an electrostatic chuck (ESC). In Patent Document 1 (JP 2019-117926 A), an electrostatic chuck is provided facing the upper surface of the substrate, and the substrate is attracted and held by applying an attraction voltage to the electrostatic chuck while the electrostatic chuck is in contact with or close to the substrate. This reduces the bending of the substrate when it is held. Patent Document 1 also discloses that a sensor is used to detect the state of attraction of the substrate to the electrostatic chuck to measure the degree of adhesion between the electrostatic chuck and the substrate, and film formation is performed with the electrostatic chuck and the substrate in close contact with each other.

JP 2019-117926 A

However, if foreign matter adheres to the surface of the electrostatic chuck, the electrostatic chuck may not be able to properly attract the substrate. For example, if an electrostatic chuck is used with a conductive material such as a deposition material attached to it, the desired attracting force may not be obtained even when an attracting voltage is applied, and the degree of adhesion between the electrostatic chuck and the substrate may decrease. Furthermore, if the substrate is attracted while particles generated in the chamber are still attached to the electrostatic chuck surface, the substrate may be damaged. Therefore, there is a need to inspect the condition of the surface of the electrostatic chuck and detect whether or not foreign matter is attached.

The present invention was made in consideration of the above problems, and its purpose is to provide a technology for detecting the surface condition of an electrostatic chuck that attracts and holds a substrate in a film formation device.

The present invention employs the following configuration.
A film forming apparatus for forming a film on a substrate,
an electrostatic chuck having an adsorption surface for adsorbing the substrate;
a detection means for detecting a state of the chucking surface when the substrate is not being chucked;
The film forming apparatus is characterized by comprising:
The present invention also employs the following configuration.
A detection device to be disposed in a film formation apparatus that forms a film on a substrate attracted by an attraction surface of an electrostatic chuck,
The detection device is characterized by comprising a detection means for detecting a state of the attraction surface when the substrate is not being attracted to the attraction surface.
The present invention also employs the following configuration.
A method for controlling a film forming apparatus that forms a film on a substrate attracted to an attracting surface of an electrostatic chuck, comprising:
The method for controlling a film forming apparatus includes a step of detecting a state of the attraction surface when the substrate is not being attracted to the attraction surface.

The present invention provides a technology for detecting the surface condition of an electrostatic chuck that attracts and holds a substrate in a film formation device.

FIG. 1 is a schematic plan view showing a configuration of a film forming apparatus; Cross-sectional view showing the internal configuration of the film forming chamber Cross-sectional view showing the relationship between adhesion of foreign matter to an electrostatic chuck and the chucking force FIG. 1 is a block diagram illustrating capacitance detection according to a first embodiment. FIG. 11 is a block diagram illustrating capacitance detection in a second embodiment. FIG. 13 is a diagram for explaining the configuration of an electrostatic chuck in the third embodiment. FIG. 13 is a diagram illustrating a configuration of an electrostatic chuck according to a modified example of the third embodiment. FIG. 13 is a diagram for explaining detection of adhesion of foreign matter in the fourth embodiment. FIG. 13 is a diagram for explaining a moving mechanism in the fourth embodiment. FIG. 13 is a diagram for explaining detection of adhesion of foreign matter in the fifth embodiment. FIG. 23 is a diagram for explaining detection of adhesion of foreign matter in the sixth embodiment. 1A to 1C are diagrams illustrating a method for manufacturing an electronic device.

The following describes in detail the embodiments of the present invention. However, the following embodiments merely exemplify preferred configurations of the present invention, and the scope of the present invention is not limited to these configurations. Furthermore, unless otherwise specified, the hardware and software configurations, processing flow, manufacturing conditions, dimensions, materials, shapes, etc. of the device in the following description are not intended to limit the scope of the present invention to only those.

The present invention is suitable for a film formation apparatus that forms a thin film of a film formation material on the surface of a film formation target such as a substrate by deposition or sputtering. The present invention can be understood as an electrostatic chuck, a detection apparatus, a substrate holding apparatus, and a film formation apparatus, as well as a detection method or a control method using these apparatus. The present invention can also be understood as an electronic device manufacturing apparatus and a control method thereof, and an electronic device manufacturing method. The present invention can also be understood as a program that causes a computer to execute the detection method or control method, or a storage medium that stores the program. The storage medium may be a non-transitory storage medium that is readable by a computer.

The substrate material in the present invention can be any material, such as glass, resin, metal, or silicon. The film-forming material can be any material, such as organic materials or inorganic materials (metals, metal oxides). In the following description, "substrate" includes substrate materials on whose surfaces one or more films have already been formed. The technology of the present invention is typically applied to manufacturing equipment for electronic devices and optical components. It is particularly suitable for organic electronic devices, such as organic EL displays equipped with organic EL elements and organic EL display devices using such displays. The present invention can also be used in thin-film solar cells and organic CMOS image sensors.

Example 1
(Device configuration)
1 is a plan view showing a schematic configuration of a film forming apparatus 1. Here, a manufacturing line for an organic EL display will be described. When manufacturing an organic EL display, a substrate of a predetermined size is carried into the manufacturing line, and after the organic EL and metal layers are formed, post-processing steps such as cutting the substrate are performed.

The film forming apparatus 1 includes a transfer chamber 130 located in the center, and multiple film forming chambers 110 (110a-110d) and mask stock chambers 120 (120a, 120b) located around the transfer chamber 130. The film forming chamber 110 includes a chamber in which film forming processing is performed on a substrate 10. The mask stock chamber 120 stores masks before and after use. A transfer robot 140 installed in the transfer chamber 130 transfers substrates S and masks M into and out of the transfer chamber 130. The transfer robot 140 is, for example, a robot having a robot hand attached to an articulated arm that holds the substrate S and mask M.

The pass chamber 150 transports the substrate S flowing from the upstream side in the substrate transport direction to the transport chamber 130. The buffer chamber 160 transports the substrate S, for which the film formation process in the transport chamber 130 has been completed, to another film formation cluster downstream. When the transport robot 140 receives the substrate S from the pass chamber 150, it transports it to one of the multiple film formation chambers 110. The transport robot 140 also receives the substrate S, for which the film formation process has been completed, from the film formation chamber 110 and transports it to the buffer chamber 160.

The film formation apparatus 1 shown in FIG. 1 constitutes one film formation cluster, and another film formation cluster can be connected to the upstream or downstream side. A swirl chamber 170 that changes the direction of the substrate 10 is provided further upstream of the pass chamber 150 and further downstream of the buffer chamber 160. Each chamber, such as the film formation chamber 110, mask stock chamber 120, transfer chamber 130, buffer chamber 160, and swirl chamber 170, is maintained in a high vacuum state during the manufacturing process.

The film forming materials in the multiple film forming chambers 110a to 110d of the film forming apparatus 1 may be the same or different. For example, a film forming source of a different film forming material may be arranged in each of the film forming chambers 110a to 110d, and a laminated structure may be formed as the substrate S moves sequentially through the film forming chambers 110a to 110d. Also, by arranging a film forming source of the same film forming material in the film forming chambers 110a to 110d, film formation may be performed on multiple substrates S in parallel. Also, a first film forming material may be arranged in the film forming chambers 110a and 110c, and a second film forming material may be arranged in the film forming chambers 110b and 110d, and the first layer may be formed in the film forming chamber 110a or 110c, and then the second layer may be formed in the film forming chamber 110b or 110.

Depending on the type of electrostatic chuck, the force of adhesion of the substrate can be increased when a conductive material is attached to the substrate. In such a case, electrostatic chucks can be effectively attached when a thin film of a metal material that will become an electrode layer has already been formed in the region of the substrate where the organic EL element is to be formed (typically the center of the substrate). For example, when organic layers are sequentially formed in deposition chambers 110b to 110d on a substrate on which an electrode layer has been formed in deposition chamber 110a, it is effective to place electrostatic chucks in deposition chambers 110b to 110d.

(Film formation chamber)
2 is a cross-sectional view showing the internal configuration of the film formation chamber 110. In the film formation chamber 110, a series of film formation processes are performed, such as receiving the substrate S and mask M from the transfer robot 140, transferring the substrate S and mask M to the transfer robot 140, aligning the substrate S and mask M relative to each other, fixing the substrate S to the mask M, and forming a film. In the following description, an XYZ orthogonal coordinate system is used in which the vertical direction is the Z direction, and rotation around the Z axis is represented by θ.

The film formation chamber 110 includes a chamber 200. The interior of the chamber 200 is maintained in a vacuum atmosphere or an inert gas atmosphere such as nitrogen gas during film formation. An electrostatic chuck C, a substrate support 210, a mask table 221, and an evaporation source 240 (film formation source) are provided inside the chamber 200.

The mask M has an opening pattern that corresponds to the thin film pattern to be formed on the substrate. For example, a metal mask in which a metal foil on which a pattern is formed is supported by a frame around the periphery can be used as the mask M. The mask M is placed on the mask table 221. In the configuration of this embodiment, the substrate S is positioned and placed on the mask, and then film formation is performed.

The substrate support 210 has multiple claw-shaped supports 210a for receiving the substrate S transported into the film formation chamber. The electrostatic chuck C is a substrate holding means in the film formation chamber, and attracts and holds the substrate S supported by the substrate support 210 by electrostatic force. The electrostatic chuck C abuts against the surface of the substrate S opposite the surface that contacts the mask M (the surface on which the film is to be formed).

A cooling member may be provided inside or on top of the electrostatic chuck C to suppress temperature rise of the substrate S during film formation and prevent alteration or deterioration of the organic material. The substrate support part 210 may also have a pressing tool corresponding to the support tool 210a. By clamping the end of the substrate S between the support tool 210a and the pressing tool, the substrate S can be held by the substrate support part 210 in addition to the electrostatic chuck C, making the substrate S more stable. A magnet may also be placed on top of the electrostatic chuck C to attract the mask M.

The evaporation source 240 is a film forming means including a container such as a crucible for containing the evaporation material, a heater, a shutter, a driving mechanism, an evaporation rate monitor, etc. Note that the film forming source is not limited to an evaporation source, and a sputtering device may also be used.

An electrostatic chuck actuator 252 and an alignment stage 280 are provided on the upper outer side of the chamber 200. The electrostatic chuck actuator 252 drives the electrostatic chuck C in the Z-axis direction via a shaft or the like to raise and lower it. This changes the relative distance between the substrate S and the mask M in a direction intersecting a plane along the deposition surface of the substrate S. The electrostatic chuck actuator 252 is composed of a motor and a ball screw, a motor and a linear guide, or the like. The electrostatic chuck C may be considered to be the substrate holding device, or the electrostatic chuck C and the power supply 290 may be considered to be the substrate holding device together. The control unit 270 may also be considered to be included in the substrate holding device. The electrostatic chuck actuator 252 may also be considered to be included in the substrate holding device.

When the electrostatic chuck C holds the substrate S supported by the substrate support part 210, the electrostatic chuck actuator 252 first lowers the electrostatic chuck C so that the electrostatic chuck C abuts or approaches the substrate S sufficiently. Then, the control part 270 controls the power supply 290 to apply a predetermined adsorption voltage to the electrode embedded in the electrostatic chuck C. This causes the substrate S to be held by the electrostatic chuck C.

Next, during alignment, the electrostatic chuck actuator 252 further lowers the electrostatic chuck C to bring the substrate S closer to the mask M. Then, the alignment stage 280 performs alignment. Next, during film formation, the evaporation source 240 releases the film formation material. When film formation is complete, the electrostatic chuck actuator 252 raises the electrostatic chuck C to transfer the substrate S with the film formed thereon to the transfer robot. Then, the voltage applied to the electrostatic chuck C is set to a predetermined peeling voltage (e.g., 0 V) to release the substrate from its hold.

The alignment stage 280 is an alignment means for moving the substrate S in the XY directions and rotating it in the θ direction. The alignment stage 280 adjusts the relative position of the substrate S and the mask M in a plane along the film formation surface of the substrate S. The alignment stage 280 includes a chamber fixing part 281 connected and fixed to the chamber 200, an actuator part 282 for performing XYθ movement, and a connection part 283 connected to the electrostatic chuck C.

Actuator unit 282 moves substrate S in the X and Y directions and rotates it in the θ direction according to control signals sent from control unit 270. The actuator unit 282 may be an actuator in which an X actuator, a Y actuator, and a θ actuator are stacked. Alternatively, a UVW type actuator in which multiple actuators work together may be used. Note that while this embodiment is configured to adjust the position of substrate S, it may also be configured to adjust the position of mask M or to adjust both substrate S and mask M, as long as substrate S and mask M can be aligned relative to each other.

A camera 261 is provided at the upper outside of the chamber 200 to perform optical imaging and generate image data. The camera 261 captures images through a vacuum sealing window provided in the chamber 200. In this embodiment, multiple cameras 261 are provided corresponding to the four corners of the substrate S. Each camera 261 is positioned so that its imaging range includes a substrate alignment mark provided at a corner of the substrate S and a mask alignment mark provided at a corner of the mask M.

During alignment, the camera 261 captures images of the substrate S and mask M and outputs image data to the control unit 270. The control unit 270 analyzes the captured image data and acquires position information of the substrate alignment mark and mask alignment mark using a method such as pattern matching processing. Then, based on the positional deviation amount between the substrate alignment mark and the mask alignment mark, it calculates the XY directions, movement distance, and rotation angle θ for moving the substrate S. Then, the calculated movement amount is converted into the drive amount of the stepping motor or servo motor equipped in each actuator of the alignment stage 280, and a control signal is generated. Note that two-stage alignment may be performed using a low-resolution but wide-field-of-view camera for rough alignment and a narrow-field-of-view but high-resolution camera for fine alignment.

The control unit 270 is an information processing device that communicates with each component of the film forming apparatus 1 via a control line or wireless communication (not shown), receives data from each component, and sends signals to each component to control the operation. The control unit 270 can be configured, for example, by a computer having a processor, memory, storage, I/O, etc. In this case, the function of the control unit 270 is realized by the processor executing a program stored in the memory or storage. As the computer, a general-purpose personal computer may be used, or an embedded computer or a PLC (programmable logic controller) may be used. Alternatively, some or all of the functions of the control unit 270 may be configured by a circuit such as an ASIC or FPGA. Note that a control unit 270 may be provided for each film forming chamber, or one control unit 270 may control multiple film forming chambers.

The power supply 290 is a high-voltage power supply device capable of supplying voltage to each component of the film forming apparatus 1 via conductive wires (not shown). The power supply 290 controls the polarity and magnitude of the applied voltage according to instructions from the control unit 270. The power supply 290 can be considered a voltage supplying means. By controlling the polarity and magnitude of the voltage (adsorption voltage) applied to the electrode of the electrostatic chuck C, the adsorption force on the substrate S can be controlled. The power supply 290 and the control unit 270 may be considered to collectively constitute the power supply of the film forming apparatus.

The application of the present invention is not limited to the cluster-type deposition apparatus described above. The present invention can also be applied to an in-line deposition apparatus in which multiple chambers are connected through a vacuum and a substrate held by a substrate carrier is moved between the chambers while a film is deposited.

(Electrostatic chuck)
The electrostatic chuck C has a structure in which an electric circuit, such as a metal electrode, is embedded in a plate-shaped base material made of ceramic or the like. Generally, there are various types of electrostatic chucks, such as a gradient force type, a Coulomb force type, and a Johnsen-Rahbek force type, depending on the principle by which the substrate is attracted to the electrostatic chuck. In any case, the attracting force can be increased by increasing the attracting voltage applied.

Gradient force type electrostatic chucks attract objects by utilizing the attraction force that occurs toward an area with a potential gradient (gradient) generated by the potential difference between the electrodes. The gradient force is generated even if the object to be attracted is an insulator, so it can hold even plain glass or a glass substrate with no conductor formed thereon. When generating the gradient force, an attraction voltage is applied so that the potential of the first electrode is higher than the reference potential of the object to be attracted and the potential of the second electrode is lower than the reference potential, based on the potential of the object to be attracted. In order to increase this gradient force, it is necessary to reduce the space between the electrodes and to arrange the electrodes closely together in order to make the potential gradient as steep as possible. Therefore, two comb-tooth electrodes with a structure in which the protruding comb teeth interdigitate with each other are suitable as electrodes to be used in gradient force type electrostatic chucks.

The Coulomb force type electrostatic chuck attracts an object to be attracted by electrostatic attraction generated by applying a positive potential voltage and a negative potential voltage to two electrodes, respectively, and is effective when the object to be attracted is a conductor. Therefore, it can be effectively attracted to a substrate on which an electrode layer of a metal material has already been formed. When the object to be attracted is in a floating state not connected to ground, it is possible to attract the object by generating polarization in the object to be attracted by facing both the positive and negative electrodes. When the object to be attracted is grounded, it can be attracted by at least one of the positive and negative electrodes. Coulomb force is generally stronger than gradient force. Also, the larger the area of the electrode facing the object to be attracted, the stronger the attraction force. Therefore, in order to increase the attraction force, it is necessary to increase the ratio of the electrode area to the area of the electrostatic chuck as much as possible.

Johnson-Rahbek force type electrostatic chucks attract conductive objects by passing a leakage current through the positive electrode, the object to be attracted, and the negative electrode in that order, and require a dielectric with a volume resistance value within a specified range to be placed between the electrode and the object to be attracted. The Johnson-Rahbek force is generally stronger than the Coulomb force. Also, with the Johnson-Rahbek force type electrostatic chuck, the greater the contact area with the object to be attracted, the stronger the chucking force can be.

(Detection of adhesion to electrostatic chuck)
With reference to Fig. 3, a change in the adsorptive force when foreign matter is attached to the surface of the electrostatic chuck C will be described. Fig. 3(a) to Fig. 3(d) are schematic cross-sectional views of the electrostatic chuck C, showing a positive electrode 250 and a negative electrode 260 embedded in a base material. The positive electrode 250 and the negative electrode 260 are connected to a power source 290, and a voltage of a desired magnitude is applied to them under the control of a control unit 270, generating an adsorptive force corresponding to the magnitude of the voltage, thereby adsorptively adsorbing the substrate S. In Fig. 3, the magnitude of the adsorptive force is represented by the number of arrows pointing from the substrate S to the electrostatic chuck C.

3A shows a state where there is no adhesion to the electrostatic chuck C, and when a voltage is applied to the electrodes in this state, an adhesion force of a designed magnitude is generated over the entire surface of the electrostatic chuck C. FIG 3B shows a state where a small amount of conductive adhesion 220 is attached to the surface of the electrostatic chuck C as a result of film formation material flying inside the chamber 200 during the film formation process. In this case, even if a voltage is applied to the electrodes, an adhesion force cannot be generated in the area where the adhesion 220 is attached, so
The suction force for the substrate S decreases.

Figure 3(c) shows a state where even more deposits 220 have adhered to the surface of the electrostatic chuck C. In this case, the adhesion force to the substrate S is further reduced. In the state of Figure 3(b) or Figure 3(c), it is possible that the adhesion force sufficient to support the weight of the substrate S is not obtained and the substrate S cannot be held. Even if the substrate S can be held, bending may occur in areas where adhesion force cannot be exerted, resulting in a decrease in the accuracy of film formation. Figure 3(d) shows a state where the deposition of the conductor has progressed further and a conductive film has been formed over the entire surface of the electrostatic chuck C. In this state, adhesion force cannot be exerted over the entire surface and the substrate S cannot be held.

Therefore, in a film formation process using the film formation apparatus 1, it is necessary to inspect the adhesion of foreign matter on the surface of the electrostatic chuck C periodically or at a desired timing, and if adhesion is detected, it is necessary to remove the foreign matter or replace the electrostatic chuck C.

Figure 4 shows a configuration for detecting conductive deposits on the surface of the electrostatic chuck C in this embodiment. A first switch 320 capable of switching between a connected state and a disconnected state is provided on the conductor that supplies power from the power source 290 to the electrodes of the electrostatic chuck C. The film forming apparatus 1 also has a capacitance detector 310 connected to both electrodes of the electrostatic chuck C. The capacitance detector 310 can be a capacitance sensor that measures the capacitance value between the two electrodes and outputs the capacitance value to the control unit 270 as an analog signal. In such a capacitance sensor, the higher the amount of conductor that is attached between the electrodes, the higher the capacitance value that is detected. A second switch 325 capable of switching between a connected state and a disconnected state is also provided on the conductor that connects the capacitance detector 310 and the electrostatic chuck C. Each switch can be considered as a switching means.

The control unit 270 converts the detection signal from the capacitance sensor into a digital signal and compares it with a capacitance value previously measured and stored in memory to determine the presence and extent of foreign matter adhesion. In this embodiment, the capacitance detection unit 310 corresponds to a detection means for detecting the state of the attraction surface when the electrostatic chuck C is not adsorbing a substrate. The capacitance detection unit 310 and the control unit 270 may be considered together as the detection means. The detection means is typically connected to an electrical path between a power source and an electrode.

The film forming apparatus 1 may also be provided with a notification unit 275 that receives instructions from the control unit 270 and notifies the user of the adhesion state of the foreign matter on the electrostatic chuck C. The notification unit 275 may have any configuration as long as it can notify the user of information. For example, if the control unit 270 is a computer, the computer's monitor and speaker may be used, or a dedicated lamp and speaker for notifying the user of the adhesion of foreign matter may be provided. When the control unit 270 detects an abnormal state regarding the electrostatic chuck C that should be notified, it notifies the user of the information via the notification unit 275.

In addition, when an abnormal state is detected, the control unit 270 may increase the set value of the adsorption voltage applied during the next film formation in place of or in addition to notification by the notification unit 275, so that the substrate S is reliably adsorbed. Specifically, when the capacitance detection value is higher than a predetermined value, or when the amount of adhesion determined from the detection value is greater than a predetermined amount, the set value of the adsorption voltage is increased.

The capacitance detection unit 310 of this embodiment detects the capacitance when no voltage is applied from the power source 290 and therefore no substrate S is attracted. Furthermore, by providing the first switch 320 and the second switch 325 as shown in the figure, it is possible to reliably switch the path when a voltage is applied and when a capacitance is detected. That is, when a capacitance is detected, the first switch 320 is in a disconnected state and the second switch 325 is in a connected state (first state), and when a voltage is applied, the first switch 320 is in a connected state and the second switch 325 is in a disconnected state (second state). Therefore, it is not necessary to use a device that can handle high voltage as the capacitance detection unit 310, and the configuration can be simplified. In this embodiment, the state detection of the electrostatic chuck C is performed at a timing when the substrate S is not attracted, for example, when the film forming apparatus is installed, after a predetermined number of substrates are formed, after the apparatus has been operated for a predetermined time, during regular or special maintenance, etc.

Table 1 shows an example of the relationship between the state of the electrostatic chuck C and the detection value in this embodiment. As described above, the greater the amount of adhesion, the greater the detection value. Note that the numerical values and adhesion amounts shown in Table 1 are merely examples, and are set appropriately depending on the configuration of the electrostatic chuck C, the type of film-forming material, the required suction force, and the like. The control unit 270 may notify the user of the detection value itself, or may notify the user of the adhesion state determined from the detection value. Moreover, the stage at which the notification is made may be set arbitrarily.

As described above, according to this embodiment, the state of the adsorption surface of the electrostatic chuck C can be detected based on the detected capacitance value, so that if there is an abnormality in the electrostatic chuck C, appropriate measures such as replacement or removal of adhering matter can be taken. This prevents film formation from being performed when the adsorption force of the electrostatic chuck C is reduced, making it possible to form a film with high accuracy.

Example 2
Next, a second embodiment of the present invention will be described. The same components as those in the first embodiment are given the same reference numerals, and the description thereof will be omitted.

Figure 5 shows the configuration for detecting conductive deposits on the surface of the electrostatic chuck C in this embodiment. The electrostatic capacitance detection unit 310 in this embodiment is provided between the power source 290 and the electrostatic chuck C. The electrostatic capacitance detection unit 310 in this embodiment has the same function as in embodiment 1 of measuring the electrostatic capacitance value between both electrodes and outputting it to the control unit 270, but also performs capacitance measurement while the chucking voltage from the power source 290 is being applied. Therefore, the electrostatic capacitance detection unit 310 in this embodiment is required to have the performance to handle the passage of high voltages.

In this embodiment, as in the first embodiment, the greater the amount of conductor adhering between the two electrodes, the higher the capacitance value detected, making it possible to notify the user of the state of the material adhering to the electrostatic chuck C.

Furthermore, in the configuration of this embodiment, the electrostatic capacitance can be continuously detected even during application of a high voltage for adsorbing the substrate S. Here, the electrostatic chuck C can effectively adsorb the substrate S on which a conductive film (e.g., an electrode layer made of a metal material) has already been formed. However, it is known that even when the electrostatic chuck C adsorbs the substrate S with such a conductive film, the detected value of the electrostatic capacitance becomes high, as in the case where a conductor is attached to the electrostatic chuck C. Therefore, the control unit 270 can also determine whether the substrate S is adsorbed to the electrostatic chuck C or whether the substrate S is peeled off from the electrostatic chuck C by comparing the detected value of the electrostatic capacitance with a preset threshold value. Furthermore, when the control unit 270 detects a sudden change in the detected value, it can determine that a change has occurred in the adsorption state or peeled state of the substrate S.

Moreover, the higher the detected value of the capacitance, the lower the attracting force, and therefore the degree of contact between the substrate S and the electrostatic chuck C decreases. Therefore, the control unit 270 of this embodiment can detect the degree of contact based on the detected value of the capacitance. Moreover, when the control unit 270 determines that the degree of contact is lower than a predetermined value, the control unit 270 may increase the attracting voltage to increase the degree of contact.

Example 3
Next, a third embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted.

Fig. 6(a) is a schematic plan view showing the configuration of the electrostatic chuck C in this embodiment. Fig. 6(b) is a schematic cross-sectional view taken along line A-A' in Fig. 6(a). The electrostatic chuck C in this embodiment is divided into a total of 12 regions ( _C11 to _C43 ) of 3 vertical and 4 horizontal. The control unit 270 and the power source 290 can individually control the application of the clamping voltage to each region.

The capacitance detection unit 310 of this embodiment is equipped with multiple capacitance detection sensors corresponding to each region. This enables parallel measurement of capacitance, shortening the measurement time. Note that a single capacitance detection unit 310 may be configured to be connected or disconnected individually from each region using a switch. Then, the capacitance is measured sequentially while switching between the regions to be connected. In this case, the measurement time will be longer, but the device configuration can be simplified.

With this configuration, it is possible to determine in which area of the electrostatic chuck C the capacitance value exceeds the threshold value. Therefore, when using a large electrostatic chuck C that is suitable for large substrates, it is easy to identify the location where foreign matter is attached. Furthermore, if foreign matter is concentrated in a specific area rather than on the entire chucking surface of the electrostatic chuck C, the chucking force can be increased by increasing the voltage applied to the electrode in that adhesion area, thereby compensating for the decrease in chucking force in the adhesion area.

When a detection means capable of detecting electrostatic capacitance even while an adsorption voltage is being applied is connected to each divided area of the electrostatic chuck C as in Example 2, it is possible to detect the adsorption state of the substrate S for each divided area of the electrostatic chuck C. In this case, the degree of adhesion between the electrostatic chuck C and the substrate S can be measured for each position.

(Modification)
FIG. 7A is a schematic plan view showing the configuration of an electrostatic chuck C in a modified example of this embodiment. FIG. 7B is a schematic cross-sectional view taken along the line B-B' in FIG. 7A. The electrostatic chuck C in this modified example is divided into a total of four areas, from an area _C1 in the center to areas _C2 , _C3 , and _C4 , in order from the area C1 toward the outside. The control unit 270 and the power source 290 can individually control the applied voltage for each area. In this modified example, instead of disposing a capacitance detection unit for each area, a configuration in which a single capacitance detection unit is connected to a different area by a switch may also be used.

In this modified example, it is also possible to identify which area of the electrostatic chuck C the foreign matter has adhered to. The configuration of this modified example is effective, for example, when the adhesion of the foreign matter progresses from the outer periphery to the inner periphery of the electrostatic chuck C, or conversely, when the adhesion progresses from the inner periphery to the outer periphery.

The method of dividing the electrostatic chuck C is not limited to the rectangular division as shown in Fig. 6 or the concentric division as shown in Fig. 7. The number of divisions is also not limited to the examples shown in the drawings. The division method and the number of divisions may be appropriately determined depending on the size of the electrostatic chuck C, the configuration of the entire device, the manufacturing cost, the required detection accuracy, and the like.

Example 4
Next, a fourth embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted.

Figure 8 shows a detection means for detecting the state of foreign matter adhering to the surface of the electrostatic chuck C in this embodiment. The detection means in this figure is a camera 370 as an imaging means capable of imaging the adsorption surface of the electrostatic chuck C. The camera 370 and the control unit 270 may be considered as a combination of the detection means. The camera 370 transmits the image acquired by imaging to the control unit 270. The control unit 270 analyzes the captured image to identify the presence or absence of adhesions on the electrostatic chuck C, the amount of adhesion, and the position of adhesion. Existing image processing technology can be used to detect adhesions based on images. For example, the captured image may be compared with an image of a state without adhesions that was captured in advance and stored in memory, and analysis may be performed based on the difference. In addition, foreign matter detection processing using edge detection processing of the captured image and foreign matter detection using machine learning can be used. The control unit 270 notifies the user of information regarding the position and amount of adhesions detected by image analysis via the notification unit 275.

In the illustrated example, the camera 370 is mounted on a moving mechanism 375. The moving mechanism 375 is a means for moving the camera 370 in a plane parallel to the adsorption surface of the electrostatic chuck C. The moving mechanism 375 moves the camera 370 on the guide rail at a predetermined scanning speed under the control of the control unit 270, thereby capturing an image of the entire electrostatic chuck C. In addition, in a configuration in which film formation is performed while scanning the evaporation source 240, the moving mechanism 375 may move both the evaporation source 240 and the camera 370.

Next, an example of the moving mechanism 375 is shown. FIG. 9(a) shows an example using a one-axis moving mechanism, and the moving mechanism 375 includes a guide rail 377 and a driving means such as a motor. In this example, multiple cameras 370 are arranged in a direction perpendicular to the scanning direction, and the width of the electrostatic chuck C in the perpendicular direction can be imaged at once. FIG. 9(b) shows an example using a two-axis moving mechanism, and includes a first guide rail 377 and a second guide rail 379. In this example, one camera 370 images the entire electrostatic chuck C while moving in the scanning direction and the perpendicular direction.

Figure 9 (c) shows another example of the moving mechanism 375. The moving mechanism 375 is a robot arm equipped with links 385a to 385c and joints 387a to 387c, and is disposed at the bottom of the chamber 200. The camera 370 is attached to the link 385c, and captures images while moving in a plane parallel to the adsorption surface of the electrostatic chuck C in accordance with the movement of the robot arm. With this configuration, images can be captured quickly at the desired position according to the user's instructions and the control of the control unit 270. Note that even in the case of Figure 9 (c), the moving mechanism 375 may function as both the moving mechanism for the evaporation source 240 and the moving mechanism for the camera 370.

Note that the movement mechanism 375 is not limited to the illustrated example as long as the camera 370 can capture an image of the entire attraction surface of the electrostatic chuck. Also, instead of moving the camera 370, a wide-angle camera capable of capturing an image of the entire electrostatic chuck C at the same time may be used as the camera 370.

Example 5
Next, a fifth embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted.

Figure 10 shows a detection means for detecting the state of adhesion of foreign matter on the surface of the electrostatic chuck C in this embodiment. The detection means in this figure is a laser distance meter 390 as a distance measurement means for measuring the distance to the adsorption surface of the electrostatic chuck C. The laser distance meter 390 irradiates a laser beam in the direction of the electrostatic chuck C and receives the reflected light from the electrostatic chuck C. The control unit 270 calculates the distance to the electrostatic chuck C based on the time from irradiation to reception. The control unit 270 also stores information in memory regarding the distance to the electrostatic chuck C at each position that the laser distance meter 390 can take, based on information at the time of designing the film formation apparatus. The control unit 270 then compares the actually measured distance with the distance stored in the memory to determine whether foreign matter is attached.

The distance measuring means is not limited to the type that uses laser light, so long as it can measure the distance to the electrostatic chuck C. A distance measuring device that uses light or radio waves other than laser light, such as a radar that uses millimeter waves or microwaves, or a distance sensor that uses ultrasonic waves, may also be used. Also, FIG. 10 shows an example in which the laser distance measuring device 390 is moved using a two-axis moving mechanism 375. However, as long as the laser distance measuring device 390 can be moved in a plane parallel to the electrostatic chuck C, a one-axis moving mechanism, a robot arm, or other moving mechanisms may also be used.

Example 6
Next, a sixth embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted.

Figure 11 shows a detection means for detecting the state of adhesion of foreign matter on the surface of the electrostatic chuck C in this embodiment. The detection means in this figure is a current measuring device 395 that measures the current by bringing a detection probe 397 close to the electrostatic chuck C. Here, the current strength of the leakage current in the electrostatic chuck C changes depending on the amount of conductor attached to the electrostatic chuck C. Therefore, the control unit 270 can determine the amount of conductor attached by measuring the leakage current using the current measuring device 395.

In FIG. 11, an example is shown in which a robot arm type moving mechanism 375 is used to move the detection probe 397. However, a one-axis or two-axis moving mechanism or other moving mechanisms may also be used.

Example 7
Next, a seventh embodiment of the present invention will be described. The same components as those in the above-described embodiments are denoted by the same reference numerals, and the description thereof will be omitted. This embodiment can be implemented by a configuration including a capacitance sensor, for example, as shown in Figs. 4 to 7. In the configuration of Fig. 4, as exemplified in Table 1, the adhesion state and amount of foreign matter, such as a film-forming material, attached to the electrostatic chuck C is detected by referring to the detected capacitance value.

As described above, when the electrostatic chuck C adsorbs a substrate S with a conductive film, the detected capacitance value becomes high, just as when foreign matter adheres to the electrostatic chuck C. It is known that the more foreign matter adheres, the smaller the amount of change in capacitance when the substrate is adsorbed.

The control unit 270 of this embodiment therefore detects the presence or absence of foreign matter and the state of adhesion (amount of adhesion) based on the amount of change in capacitance when the substrate S is attracted. That is, the control unit 270 detects the state of adhesion of foreign matter based on a table or formula that is stored in advance in memory and that represents the relationship between the state of adhesion of foreign matter and the amount of change in capacitance value when the substrate is attracted, and notifies the user.

According to the configuration of this embodiment, in addition to or separately from the methods of embodiments 1 to 3, it is possible to detect the presence or absence and state of adhesion of foreign matter based on the change in capacitance when the substrate is attracted, thereby further improving the detection accuracy.

Example 8
Next, an eighth embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted. This embodiment can also be implemented by a configuration including a capacitance sensor as shown in FIG. 4 to FIG. 7.

Here, we consider the wear of the electrostatic chuck C. The electrostatic chuck C has a structure in which an electric circuit is embedded in a base material such as ceramic, and the base material gradually wears away with the passage of time of use. According to the inventor's knowledge, if there is no foreign matter adhering to the electrostatic chuck C, there is almost no change in the capacitance value between before and after wear. However, the amount of change (increase) in the capacitance value when the electrostatic chuck C adsorbs the substrate S is greater after wear than before wear.

The control unit 270 of this embodiment therefore detects the presence or absence of wear in the electrostatic chuck C and the degree of wear based on the amount of change in capacitance when the substrate S is attracted. That is, the control unit 270 detects the wear status of the electrostatic chuck based on a table or formula that is stored in advance in memory and that represents the relationship between the presence or absence and the degree of wear in the electrostatic chuck C and the amount of change in the capacitance value when the substrate is attracted, and notifies the user.

According to the configuration of this embodiment, the wear status of the electrostatic chuck C can be detected based on the change in electrostatic capacitance when the substrate is attracted. Therefore, for example, it becomes possible to calculate the lifespan and replacement time of the electrostatic chuck C and notify the user.

<Example 9>
Next, a ninth embodiment of the present invention will be described. The same components as those in the above-mentioned embodiments are given the same reference numerals, and the description thereof will be omitted. This embodiment can be implemented by a configuration including a means for measuring distance, as shown in FIG.

In the example of FIG. 10, the control unit 270 detects the adhesion state of foreign matter to the electrostatic chuck C by comparing the distance to the electrostatic chuck C measured using a distance meter or the like with the distance stored in memory. In this embodiment, the control unit 270 detects the wear state of the electrostatic chuck C in addition to or together with the adhesion state of foreign matter. That is, if the distance to the electrostatic chuck C is shorter than the value stored in memory, the control unit 270 determines that foreign matter is attached to the electrostatic chuck C. On the other hand, if the distance to the electrostatic chuck C is longer than the value stored in memory, the control unit 270 determines that the electrostatic chuck C is worn.

As described above, the condition of foreign matter adhesion may differ for each region of the electrostatic chuck C. According to this embodiment, it is possible to detect the condition of foreign matter adhesion for each region by measuring the distance to the electrostatic chuck C for each part by scanning a distance meter or the like. For example, when measuring the distance while scanning the electrostatic chuck C, there are "(a) a position where the distance is longer than when it was new" and "(b) a position where the distance is the same (or shorter) than when it was new." In this case, since the electrostatic chuck C wears out overall, it is considered that the amount of adhesion is large at position (a), and therefore the decrease in distance due to foreign matter adhesion is greater than the increase in distance due to wear. On the other hand, it is considered that at position (b), the increase in distance due to wear and the decrease in distance due to foreign matter adhesion are balanced (or the latter is greater).

According to the configuration of this embodiment, it is possible to detect the wear state of the electrostatic chuck C in addition to or separately from the adhesion state of foreign matter to the electrostatic chuck C. Therefore, for example, it is possible to calculate the life or replacement time of the electrostatic chuck C and notify the user of the results.

<Method of Manufacturing Electronic Device>
Next, an example of a method for manufacturing an electronic device using the film forming apparatus according to this embodiment will be described below. The configuration of an organic EL display device will be shown as an example of an electronic device, and a method for manufacturing the organic EL display device will be illustrated.

First, the organic EL display device to be manufactured will be described. Figure 12(a) shows an overall view of the organic EL display device 700, and Figure 12(b) shows the cross-sectional structure of one pixel.

As shown in FIG. 12(a), a display area 701 of an organic EL display device 700 has a plurality of pixels 702 each having a plurality of light-emitting elements arranged in a matrix. As will be described in detail later, each light-emitting element has a structure including an organic layer sandwiched between a pair of electrodes. Note that the pixel here refers to the smallest unit that allows a desired color to be displayed in the display area 701. In the case of the organic EL display device according to this embodiment, the pixel 702 is configured by a combination of a first light-emitting element 702R, a second light-emitting element 702G, and a third light-emitting element 702B that emit light different from each other. The pixel 702 is often configured by a combination of a red light-emitting element, a green light-emitting element, and a blue light-emitting element, but may also be a combination of a yellow light-emitting element, a cyan light-emitting element, and a white light-emitting element, and is not particularly limited as long as it is at least one color.

Figure 12 (b) is a schematic partial cross-sectional view taken along line B-B in Figure 12 (a). The pixel 702 is made up of a plurality of light-emitting elements, and each light-emitting element has a first electrode (anode) 704, a hole transport layer 705, one of the light-emitting layers 706R, 706G, and 706B, an electron transport layer 707, and a second electrode (cathode) 708 on a substrate 703. Of these, the hole transport layer 705, the light-emitting layers 706R, 706G, and 706B, and the electron transport layer 707 are organic layers. In this embodiment, the light-emitting layer 706R is an organic EL layer that emits red light, the light-emitting layer 706G is an organic EL layer that emits green light, and the light-emitting layer 706B is an organic EL layer that emits blue light. The light-emitting layers 706R, 706G, and 706B are formed in patterns corresponding to the light-emitting elements (sometimes referred to as organic EL elements) that emit red, green, and blue light, respectively.

The first electrode 704 is formed separately for each light-emitting element. The hole transport layer 705, the electron transport layer 707, and the second electrode 708 may be formed in common for the multiple light-emitting elements 702R, 702G, and 702B, or may be formed for each light-emitting element. In order to prevent the first electrode 704 and the second electrode 708 from shorting due to foreign matter, an insulating layer 709 is provided between the first electrodes 704. Furthermore, since the organic EL layer deteriorates due to moisture and oxygen, a protective layer 710 is provided to protect the organic EL element from moisture and oxygen.

In FIG. 12(b), the hole transport layer 705 and the electron transport layer 707 are shown as a single layer, but depending on the structure of the organic EL display element, they may be formed of multiple layers including a hole blocking layer and an electron blocking layer. In addition, a hole injection layer having an energy band structure that can smoothly inject holes from the first electrode 704 to the hole transport layer 705 can be formed between the first electrode 704 and the hole transport layer 705. Similarly, an electron injection layer can be formed between the second electrode 708 and the electron transport layer 707.

Next, we will explain in detail an example of a manufacturing method for an organic EL display device.

First, a circuit (not shown) for driving the organic EL display device and a substrate (mother glass) 703 on which a first electrode 704 is formed are prepared.

An acrylic resin is formed by spin coating on the substrate 703 on which the first electrode 704 is formed.
The acrylic resin is patterned by lithography so as to form an opening in the portion where the first electrode 704 is formed, thereby forming an insulating layer 709. This opening corresponds to a light-emitting region where the light-emitting element actually emits light.

The substrate 703 with the patterned insulating layer 709 is placed on a substrate carrier on which an adhesive member is arranged. The substrate 703 is held by the adhesive member. It is then carried into a first organic material deposition apparatus and, after inversion, a hole transport layer 705 is deposited as a common layer on the first electrode 704 in the display area. The hole transport layer 705 is deposited by vacuum deposition. In practice, the hole transport layer 705 is formed to be larger than the display area 701, so no high-resolution mask is required.

Next, the substrate 703 on which the hole transport layer 705 has been formed is carried into a second organic material deposition apparatus. The substrate and the mask are aligned, the substrate is placed on the mask, and a red-emitting light-emitting layer 706R is deposited on the portion of the substrate 703 where the red-emitting element is to be located.

Similar to the deposition of the light-emitting layer 706R, the third organic material deposition apparatus deposits the light-emitting layer 706G that emits green light, and the fourth organic material deposition apparatus deposits the light-emitting layer 706B that emits blue light. After the deposition of the light-emitting layers 706R, 706G, and 706B is completed, the fifth deposition apparatus deposits the electron transport layer 707 over the entire display area 701. The electron transport layer 707 is formed as a layer common to the three light-emitting layers 706R, 706G, and 706B.

The substrate on which the electron transport layer 707 has been formed is moved using a metallic deposition material deposition device to deposit the second electrode 708.

Then, the substrate is transferred to a plasma CVD device, where a protective layer 710 is deposited, completing the deposition process on the substrate 703. After inversion, the adhesive member is peeled off from the substrate 703, thereby separating the substrate 703 from the substrate carrier. The organic EL display device 700 is then completed after cutting.

If the substrate 703 on which the insulating layer 709 is patterned is exposed to an atmosphere containing moisture or oxygen from the time it is carried into the deposition apparatus until the deposition of the protective layer 710 is completed, the light-emitting layer made of the organic EL material may be deteriorated by moisture or oxygen. Therefore, in this embodiment, the substrate is carried in and out of the deposition apparatus in a vacuum atmosphere or an inert gas atmosphere.

1: Film forming device, 310: Capacitance detection unit, C: Electrostatic chuck, S: Substrate

Claims (22)

A film forming apparatus for forming a film on a substrate,
an electrostatic chuck having an adsorption surface for adsorbing the substrate;
a detection means for detecting a state of the chucking surface when the substrate is not being chucked;
A film forming apparatus comprising: the electrostatic chuck has an electrode to which a voltage for attracting the substrate is applied,
2. The film forming apparatus according to claim 1, wherein the detection means detects the electrostatic capacitance of the electrode. 3. The film forming apparatus according to claim 2, wherein the detection means detects the state or presence of an object attached to the attraction surface based on a detected value of the capacitance. The film forming apparatus according to claim 3, characterized in that the detection means determines that the amount of the adhesion is greater as the detected capacitance value is higher. 2. The film forming apparatus according to claim 1, wherein the detection means detects the state or presence of an object adhering to the attraction surface. the electrostatic chuck has an electrode to which a voltage for attracting the substrate is applied,
2. The film forming apparatus according to claim 1, further comprising a voltage supplying means for controlling a voltage applied to the electrode based on a detection result of the detecting means. The detection means detects the state or presence of an object attached to the adsorption surface,
7. The film forming apparatus according to claim 6, wherein said voltage supplying means increases said voltage when the amount of said deposit is greater than a predetermined amount. 7. The film forming apparatus according to claim 6, further comprising a switching means for switching between a first state in which the electrode is connected to the detection means and not connected to the voltage supply means, and a second state in which the connection between the detection means and the electrode is cut off. 7. The film forming apparatus according to claim 6, wherein the detection means is connected to an electric path between the electrode and the voltage supply means. 2. The film forming apparatus according to claim 1, wherein the detection means further detects the degree of contact between the substrate and the electrostatic chuck. a voltage supplying means for controlling a voltage supplied to the electrostatic chuck based on a detection result of the detecting means;
11. The film forming apparatus according to claim 10, wherein the voltage supply means increases the voltage when the degree of adhesion between the substrate and the electrostatic chuck is lower than a predetermined value. the electrostatic chuck is divided into a plurality of regions each having an electrode to which a voltage for attracting the substrate is applied,
2. The film forming apparatus according to claim 1, wherein the detection means detects the capacitance of the electrode for each of the plurality of regions. 13. The film forming apparatus according to claim 12, wherein a set value of an attraction voltage applied to said electrode in a region determined by said detection means to have an abnormality among said plurality of regions is increased. 2. The film forming apparatus according to claim 1, wherein the detection means is an image capturing means for capturing an image of the electrostatic chuck, and detects the state of the attracting surface based on the captured image. 2. The film forming apparatus according to claim 1, wherein the detection means is a distance measurement means for measuring a distance to the electrostatic chuck, and detects a state of the attraction surface based on the distance from the detection means to the electrostatic chuck. 2. The film forming apparatus according to claim 1, wherein the detection means is a current measurement means for measuring a leakage current of the electrostatic chuck, and detects the state of the attracting surface based on a measured current intensity. 17. The film deposition apparatus according to claim 14, further comprising a moving mechanism that moves the detection means in a plane parallel to the attraction surface of the electrostatic chuck. 2. The film forming apparatus according to claim 1, further comprising a notification unit that notifies a user when the detection unit detects an abnormality in the state of the attraction surface. 3. The film forming apparatus according to claim 2, wherein the detection means detects a change in electrostatic capacitance when the electrostatic chuck attracts the substrate. 2. The film forming apparatus according to claim 1, wherein the detection means further detects a wear state of the electrostatic chuck. A detection device to be disposed in a film formation apparatus that forms a film on a substrate attracted by an attraction surface of an electrostatic chuck,
A detection device comprising: a detection means for detecting a state of the attraction surface when the substrate is not being attracted to the attraction surface. A method for controlling a film forming apparatus that forms a film on a substrate attracted to an attracting surface of an electrostatic chuck, comprising:
11. A method for controlling a film forming apparatus, comprising the step of: detecting a state of the attraction surface when the substrate is not being attracted to the attraction surface.

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