Film forming apparatus and control method for film forming apparatus

Abstract

The present application provides a technology capable of more accurately and simply grasping the state of a device to perform film formation control. The present application relates to a film formation device and a control method of a film formation device, characterized in that film formation is performed by rate control, the rate control is control in which a heating control section controls the amount of power supplied to a heating source in such a manner that a film formation rate acquired by an acquisition section is maintained at a prescribed value, when the film formation rate acquired by the acquisition section exceeds a prescribed threshold value, film formation is switched from the rate control to power control, the power control is control in which the heating control section performs power supply to the heating source at an amount of power set independently of the film formation rate acquired by the acquisition section, and when the power control is being performed, the state of the film formation device is determined based on a variation in the amount of variation in the resonance frequency of a crystal oscillator in a prescribed period when the rotational speed of a rotating body is varied in such a manner that the length of the period in which the rotating body is in a prescribed non-shielding state varies in the prescribed period.

Description

[0001] This application is a divisional application of a patent application with the application date of August 30, 2019, the application number of 201910811028.6, and the invention title of "Film formation device and control method of film formation device". TECHNICAL FIELD

[0002] The present application relates to a film formation device that forms a thin film on a film formation target by a vacuum evaporation method, and a control method of the film formation device. BACKGROUND

[0003] As a film formation device that forms a thin film on a substrate as a film formation target, a film formation device of a vacuum evaporation method is known, which is configured to heat a container (crucible) in which a film formation material is stored in a vacuum chamber, and to cause the film formation material to evaporate (sublimate or gasify) to be ejected outside the container, thereby to be attached and accumulated on the surface of the substrate. In the above film formation device, a device structure is known in which a monitoring unit provided in the vacuum chamber is used to acquire a film formation rate and feedback to the heating control of the container in order to obtain a desired film thickness. The monitoring unit is provided with a crystal oscillator, and the film formation rate is acquired based on the change in the natural frequency of the crystal oscillator due to the attachment of the film formation material. If the amount of attachment of the film formation material to the crystal oscillator excessively increases, the change in the amount of attachment cannot be accurately represented as a change in the natural frequency, and thus a new crystal oscillator needs to be replaced.

[0004] Here, the amount of attachment of the film formation material to the crystal oscillator is not an amount that will always be stable if the heating control is constant, and for example, there are cases where the amount of attachment suddenly changes due to a sudden boiling of the film formation material. Such sudden changes in the amount of attachment of the film formation material can cause the film formation amount on the actual substrate to deviate from the monitoring value or miss the appropriate replacement timing of the crystal oscillator, and thus can cause a decrease in the monitoring accuracy of the film formation rate. In Patent Literature 1, a structure is disclosed in which it is detected whether or not an undesirable spatter due to a sudden boiling of an evaporation raw material in the crucible is generated by comparing the monitoring value with a reference value set in advance.

[0005] However, the variation in the monitoring value is sometimes generated due to a poor or failure state of the monitoring unit, and thus there are cases where it is difficult to directly determine the cause of the variation in the monitoring value from the monitoring value. In addition, in the case of the monitoring unit provided in the vacuum chamber, it is difficult to directly confirm the operation state thereof, and the existence of such a confirmation operation can greatly affect the production rhythm.

[0006] PRIOR ART DOCUMENTS

[0007] PATENT LITERATURE

[0008] Patent Literature 1: Japanese Patent Application Laid-Open No. 2006-45581 SUMMARY

[0009] Problem to be solved by the Invention

[0010] An object of the present application is to provide a technology capable of more accurately and simply grasping a state of an apparatus to perform film formation control.

[0011] Means for solving the problem

[0012] To achieve the above object, a film formation apparatus of the present application includes:

[0013] a chamber that houses a film formation target;

[0014] a heating control section that controls electric power supplied to a heating source for heating a film formation material housed in a container disposed inside the chamber;

[0015] a monitoring unit disposed inside the chamber for detecting a film formation rate of the film formation material with respect to the film formation target, the monitoring unit including a crystal oscillator and a rotating body having a shielding portion and an opening portion and disposed between the crystal oscillator and the container;

[0016] a rotation control section that controls rotation of the rotating body to obtain either a shielding state in which the shielding portion is positioned between the container and the crystal oscillator or a non-shielding state in which the opening portion is positioned between the container and the crystal oscillator; and

[0017] an acquisition section that acquires the film formation rate based on a change in a resonance frequency of the crystal oscillator,

[0018] the film formation apparatus for forming a film composed of the film formation material on the film formation target, characterized in that

[0019] a state determination section determines that the monitoring unit is in a failure state when a change amount of the resonance frequency in a prescribed period when the rotation control section varies a rotation speed of the rotating body in a manner that a length of a period in the prescribed period in which the non-shielding state is assumed changes is not a change amount corresponding to a change in the length of the period in the prescribed period in which the non-shielding state is assumed or does not fall within a prescribed range in a state in which the heating control section maintains the electric power supplied to the heating source constant.

[0020] To achieve the above object, a control method of a film formation apparatus of the present application is designed such that the film formation apparatus includes:

[0021] a chamber that houses a film formation target;

[0022] a heating control section that controls electric power supplied to a heating source for heating a film formation material housed in a container arranged in the chamber;

[0023] a monitoring section arranged in the chamber for detecting a film formation rate of the film formation material with respect to a film formation object, the monitoring section including a crystal oscillator and a rotating body having a shielding section and an opening section and arranged between the crystal oscillator and the container;

[0024] a rotation control section that controls rotation of the rotating body to obtain either a shielding state in which the shielding section is positioned between the container and the crystal oscillator or a non-shielding state in which the opening section is positioned between the container and the crystal oscillator; and

[0025] an acquisition section that acquires the film formation rate based on a change in a resonance frequency of the crystal oscillator,

[0026] the film formation apparatus is used to form a film composed of the film formation material on the film formation object,

[0027] the control method of the film formation apparatus is characterized by including:

[0028] a first process in which the film formation is performed by rate control that is control by the heating control section to control an amount of electric power supplied to the heating source in such a manner that the film formation rate acquired by the acquisition section is maintained at a prescribed value;

[0029] a second process in which, when the film formation rate acquired by the acquisition section exceeds a prescribed threshold value, the film formation is performed by switching from the rate control to power control that is control by the heating control section to supply electric power to the heating source in an amount set independently of the film formation rate acquired by the acquisition section;

[0030] a third process in which the rotation control section varies a rotation speed of the rotating body in such a manner that a length of a period in which the non-shielding state is assumed during a prescribed period during the second process is changed; and

[0031] a fourth process in which, when the resonance frequency during the prescribed period in which the rotation speed is varied in the third process is not varied in an amount corresponding to a change in the length of the period in which the non-shielding state is assumed during the prescribed period or does not fall within a prescribed range, it is determined that the monitoring section is in a state in which a failure has occurred.

[0032] Effects of the Invention

[0033] According to the present invention, the condition of the device can be more accurately and easily controlled for film formation. Attached Figure Description

[0034] Figure 1 This is a schematic cross-sectional view of a film-forming apparatus according to an embodiment of the present invention.

[0035] Figure 2 This is a schematic diagram illustrating the structure of a film formation rate monitoring device according to an embodiment of the present invention.

[0036] Figure 3 This is a schematic diagram illustrating the structure of the crystal monitoring head and shielding component according to an embodiment of the present invention.

[0037] Figure 4 This is a flowchart illustrating the power supply control of the heater in an embodiment of the present invention.

[0038] Figure 5 This is an explanatory diagram of the rotation control of the shielding member according to an embodiment of the present invention. Detailed Implementation

[0039] Hereinafter, preferred embodiments and examples of the present invention will be described with reference to the accompanying drawings. However, the following embodiments and examples are merely examples illustrating preferred structures of the present invention, and the scope of the present invention is not limited to these structures. Furthermore, regarding the hardware and software structures, processing flows, manufacturing conditions, dimensions, materials, shapes, etc., of the device described below, unless specifically stated otherwise, it is understood that the scope of the present invention is not limited thereto.

[0040] [Example 1]

[0041] Reference Figures 1-5A film formation rate monitoring device and a film formation device according to an embodiment of the present application will be described. The film formation device according to the present embodiment is a film formation device that forms a thin film on a substrate by vacuum deposition. The film formation device according to the present embodiment is used to deposit and form a thin film on a substrate (including a member on which a laminate is formed) in the production of various electronic devices, optical members, and the like. More specifically, the film formation device according to the present embodiment is preferably used in the production of electronic devices such as light emitting elements, photoelectric conversion elements, and touch panels. Among them, the film formation device according to the present embodiment can be particularly preferably used in the production of organic light emitting elements such as organic EL (Erectro Luminescence) elements, and organic photoelectric conversion elements such as organic thin film solar cells. Note that the electronic device in the present application also includes a display device (for example, an organic EL display device) having a light emitting element, an illumination device (for example, an organic EL illumination device), and a sensor (for example, an organic CMOS image sensor) having a photoelectric conversion element. The film formation device according to the present embodiment can be used as a part of a film formation system including a sputtering device and the like.

[0042] Brief structure of film formation device

[0043] Figure 1 is a schematic view showing the structure of a film formation device 2 according to an embodiment of the present application. The film formation device 2 has a vacuum chamber (film formation chamber, deposition chamber) 200 in which the inside is maintained in a vacuum atmosphere or a non-active gas atmosphere such as nitrogen by an exhaust device 24 and a gas supply device 25. Note that, in the present specification, "vacuum" refers to a state in a space filled with a gas having a lower pressure than atmospheric pressure.

[0044] A substrate 100 that is a film formation target is carried into the inside of the vacuum chamber 200 by a carrying robot (not shown) and is placed on the upper surface of a mask 220 by a substrate holding unit (not shown) provided in the inside of the vacuum chamber 200. The mask 220 is a metal mask having an opening pattern 221 corresponding to a pattern of a thin film to be formed on the substrate 100 and is provided in the inside of the vacuum chamber 200 in parallel with the horizontal plane. The substrate 100 is placed on the upper surface of the mask 220 by the substrate holding unit, and thus the substrate 100 is disposed in the inside of the vacuum chamber 200 in a state in which the lower surface as a processed surface is covered with the mask 220 in parallel with the horizontal plane.

[0045] An evaporation source device 300 is provided inside the vacuum chamber 200 at a position below the mask 220. The evaporation source device 300 generally includes a container (crucible) 301 (hereinafter referred to as the container 301) that houses a film formation material (evaporation material) 400, and a heater 302 as a heating mechanism (heating source) that heats the film formation material 400 housed in the container 301. The film formation material 400 in the container 301 is evaporated in the container 301 due to heating by the heater 302, and is ejected outside the container 301 via a nozzle 303 provided at an upper portion of the container 301. The film formation material 400 ejected outside the container 301 is vapor-deposited on a surface of the substrate 100 provided above the device 300 in correspondence with the opening pattern 221 provided on the mask 220.

[0046] The heater 302 is formed by winding a wire-shaped heating element that generates heat by electric conduction around the outer periphery of the cylindrical portion of the container 301 multiple times. Note that the heater 302 can also be formed by winding multiple heating elements. As the heater 302, a heater using a metal heating resistor such as stainless steel can also be used as the heating element, and a carbon heater or the like can also be used.

[0047] The evaporation source device 300 can further include a reflection member or a heat transfer member for improving the heating efficiency of the heater 302, a frame that houses the entire structure of the evaporation source device 300 including the above-described members, a baffle, or the like (not shown) in addition to the above-described structure. In addition, the evaporation source device 300 can be configured to be relatively movable with respect to the substrate 100 that is fixedly placed in order to uniformly form a film on the entire substrate 100.

[0048] The film formation device 2 of the present embodiment is provided with the film formation rate monitoring device 1 as a mechanism for detecting the amount of vapor of the film formation material 400 ejected from the container 301 or the film thickness of the thin film formed on the substrate 100. The film formation rate monitoring device 1 is configured such that a portion of the film formation material 400 ejected from the container 301 adheres to the crystal oscillator provided on the crystal monitoring head 11 under the operation of intermittently switching the shielding state and the non-shielding state of the shielding member 12 as a rotating body. By detecting the amount of change (decrease) in the resonance frequency (natural frequency) of the crystal oscillator due to the accumulation of the film formation material 400, the amount of adhesion (accumulation) of the film formation material 400 per unit time can be obtained as the film formation rate (vapor deposition rate) corresponding to the prescribed control target temperature. By feeding back the film formation rate to the setting of the control target temperature in the heating control of the heater 302, the film formation rate can be arbitrarily controlled. Thus, the film formation rate monitoring device 1 can be used to detect the amount of ejection of the film formation material 400 or the film thickness on the substrate 100 at all times during the film formation process, and thus a film formation with high precision can be performed. The control section (arithmetic processing device) 20 of the film formation device 2 of the present embodiment has a monitoring control section 21 that controls the operation of the monitoring unit 10, measures, and obtains the film formation rate, and a heating control section 22 that performs the heating control of the evaporation source device 300.

[0049] Film formation rate monitoring device

[0050] Figure 2 is a schematic view showing the outline structure of the film formation rate monitoring device 1 of the present embodiment. As shown in Figure 2 the film formation rate monitoring device 1 of the present embodiment is provided with a monitoring unit 10 having the monitoring head 11, the shielding member 12, and the like, and a monitoring control section 21. The monitoring unit 10 is provided with the monitoring head 11, the shielding member 12, a servo motor 16 as a rotation drive source of a crystal holder (rotating support body) 14 incorporated in the crystal monitoring head 11, and a servo motor 15 as a rotation drive source of the shielding member 12. The monitoring control section 21 has a shielding member control section (rotation control section) 212 that controls the rotation drive of the shielding member 12, a film formation rate acquisition section 213 that acquires the resonance frequency (amount of change) of the crystal oscillator 13, and a holder control section 214 that controls the rotation drive of the crystal holder 14.

[0051] Figure 3 is a schematic view showing the arrangement relationship of the monitoring head 11 (crystal holder 14) and the shielding member 12 when each is observed in the direction of the respective rotation axis. As shown in Figure 3As shown, a crystal holder 14 that supports a plurality of crystal oscillators 13 (13a, 13b) at equal intervals in the circumferential direction is incorporated inside the monitoring head 11. A monitoring opening 11a, which is slightly larger than the crystal oscillators 13, is provided in the monitoring head 11, and the crystal holder 14 supports one of the crystal oscillators 13 at a position (rotational phase) that is exposed to the outside (vapor deposition source device 300) via the monitoring opening 11a.

[0052] As shown in FIG. 2, the crystal holder 14 is connected at the center to the motor shaft 16a of the servo motor 16, and is rotated by the servo motor 16. Thus, the crystal oscillator 13 exposed to the outside via the monitoring opening 11a can be switched sequentially. That is, of the plurality of crystal oscillators 13 supported by the crystal holder 14, one crystal oscillator 13a is at a position where the phase overlaps the monitoring opening 11a, and the other crystal oscillators 13b are at positions hidden inside the monitoring head 11 as crystal oscillators that have been used or replaced. When the crystal oscillator 13 exposed to the outside via the monitoring opening 11a reaches the end of life because the amount of the deposited film material 400 exceeds the prescribed amount, the crystal holder 14 is rotated to move a new crystal oscillator 13 to the exposed position overlapping the monitoring opening 11a. Figure 2 Figure 3 The rotation control of the servo motor 16 by the holder control section 214 is performed based on the rotational position (rotational phase) of the crystal holder 14 detected by the phase position detection mechanism 18 composed of the detection section 18a and the detected section 18b. Note that as the position (phase) detection mechanism, a known position sensor such as a rotary encoder can be used.

[0053] As shown in FIG. 2, the crystal holder 14 is connected at the center to the motor shaft 16a of the servo motor 16, and is rotated by the servo motor 16. Thus, the crystal oscillator 13 exposed to the outside via the monitoring opening 11a can be switched sequentially. That is, of the plurality of crystal oscillators 13 supported by the crystal holder 14, one crystal oscillator 13a is at a position where the phase overlaps the monitoring opening 11a, and the other crystal oscillators 13b are at positions hidden inside the monitoring head 11 as crystal oscillators that have been used or replaced. When the crystal oscillator 13 exposed to the outside via the monitoring opening 11a reaches the end of life because the amount of the deposited film material 400 exceeds the prescribed amount, the crystal holder 14 is rotated to move a new crystal oscillator 13 to the exposed position overlapping the monitoring opening 11a.

[0054] As shown in FIG. 2, the crystal holder 14 is connected at the center to the motor shaft 16a of the servo motor 16, and is rotated by the servo motor 16. Thus, the crystal oscillator 13 exposed to the outside via the monitoring opening 11a can be switched sequentially. That is, of the plurality of crystal oscillators 13 supported by the crystal holder 14, one crystal oscillator 13a is at a position where the phase overlaps the monitoring opening 11a, and the other crystal oscillators 13b are at positions hidden inside the monitoring head 11 as crystal oscillators that have been used or replaced. When the crystal oscillator 13 exposed to the outside via the monitoring opening 11a reaches the end of life because the amount of the deposited film material 400 exceeds the prescribed amount, the crystal holder 14 is rotated to move a new crystal oscillator 13 to the exposed position overlapping the monitoring opening 11a. Figure 3 As shown in FIG. 2, the crystal holder 14 is connected at the center to the motor shaft 16a of the servo motor 16, and is rotated by the servo motor 16. Thus, the crystal oscillator 13 exposed to the outside via the monitoring opening 11a can be switched sequentially. That is, of the plurality of crystal oscillators 13 supported by the crystal holder 14, one crystal oscillator 13a is at a position where the phase overlaps the monitoring opening 11a, and the other crystal oscillators 13b are at positions hidden inside the monitoring head 11 as crystal oscillators that have been used or replaced. When the crystal oscillator 13 exposed to the outside via the monitoring opening 11a reaches the end of life because the amount of the deposited film material 400 exceeds the prescribed amount, the crystal holder 14 is rotated to move a new crystal oscillator 13 to the exposed position overlapping the monitoring opening 11a.

[0055] Figure 2 As shown in FIG. 2, the crystal holder 14 is connected at the center to the motor shaft 16a of the servo motor 16, and is rotated by the servo motor 16. Thus, the crystal oscillator 13 exposed to the outside via the monitoring opening 11a can be switched sequentially. That is, of the plurality of crystal oscillators 13 supported by the crystal holder 14, one crystal oscillator 13a is at a position where the phase overlaps the monitoring opening 11a, and the other crystal oscillators 13b are at positions hidden inside the monitoring head 11 as crystal oscillators that have been used or replaced. When the crystal oscillator 13 exposed to the outside via the monitoring opening 11a reaches the end of life because the amount of the deposited film material 400 exceeds the prescribed amount, the crystal holder 14 is rotated to move a new crystal oscillator 13 to the exposed position overlapping the monitoring opening 11a. Figure 3 ​​As shown, the relative position (relative phase) of the opening slit 12a with respect to the monitoring opening 11a is changed between a position (opening position, non-shielding position) overlapping the monitoring opening 11a and a position (non-opening position, shielding position) not overlapping the monitoring opening 11a by rotating the shielding member 12. Thereby, the region of the shielding member 12 other than the opening slit 12a becomes the shielding portion 12b, and when the shielding portion 12b overlaps (covers) the monitoring opening 11a, it becomes a shielding state (non-opening state) that prevents the deposition material 400 from adhering to the crystal oscillator 13a. On the other hand, when the opening slit 12a overlaps the monitoring opening 11a, it becomes a non-shielding state (opening state) that allows the deposition material 400 to adhere to the crystal oscillator 13a.

[0056] The shielding member control portion 212 controls the rotation of the servo motor 15 based on the rotational position (rotational phase) of the shielding member 12 detected by the phase position detection mechanism 17 composed of the detection portion 17a and the detected portion 17b. Note that, as the position (phase) detection mechanism, a known position sensor such as a rotary encoder can be used.

[0057] The opening slit 12a is formed as a closed hole in this embodiment, but can be formed as a slit shape open at the peripheral end of the shielding member 12. Also, the number of opening slits provided can be two or more, and the slit shape is not limited to the fan shape shown in this embodiment, and various shapes can be used. In the case where a plurality of opening slits 12a are provided, they can be provided in different shapes from each other.

[0058] The crystal oscillator 13a is connected to the external resonator 19 via an electrode, a coaxial cable, or the like. A transmission signal generated by applying a voltage between the thin film of the deposition material 400 deposited on the surface of the crystal oscillator 13a and the electrode on the back surface is transmitted from the resonator 19 to the deposition rate acquisition portion 213 as a change in the resonance frequency of the crystal oscillator 13, and is acquired.

[0059] Although not shown, a flow path in which cooling water for cooling the heat generated by the motors 15, 16 that become heat sources is caused to flow is provided in the monitoring unit 10.

[0060] Note that the structure of the deposition rate monitoring apparatus shown here is only an example, and the deposition rate monitoring apparatus is not limited thereto, and various known structures can be used.

[0061] <Features of this embodiment>

[0062] Figure 4Fig. 6 is a flowchart of power supply control to the heater 302 in the film formation apparatus 2 of the present embodiment. The control subject of the flow to be described below is the control section 20 described above, which also functions as the state determination section of the present application.

[0063] The amount of heat generated by the heater 302 is controlled by controlling the amount of electric power (current value) supplied to the heater 302 using the heating control section 22 including a power supply circuit. The amount of electric power supplied is adjusted, for example, using PID control in such a manner that the temperature detected by a temperature detection mechanism not shown is maintained at a prescribed control target temperature appropriate for obtaining a desired film formation rate. By maintaining the amount of heat generated by the heater 302 (electric power supplied to the heater 302) that enables a prescribed film formation rate for a prescribed time, a thin film of a desired film thickness can be formed on the film formation surface of the substrate 100

[0064] In the film formation apparatus 2 of the present embodiment, as the control method of the supplied electric power in the heating control of the heater 302, a method is set in which rate control and average power control can be switched and performed. Note that the electric power control method is not limited to this.

[0065] In the rate control, the control target temperature is changed in time in such a manner that the monitored value (measured value) of the film formation rate acquired by the film formation rate monitoring apparatus 1 coincides with the desired target rate (theoretical value), and the amount of supplied electric power to the heater 302 is controlled in accordance with the set control target temperature.

[0066] In the present embodiment, as the electric power control of the amount of supplied electric power to the heater 302 that is decided independently of the monitored value (measured value) of the film formation rate acquired by the film formation rate monitoring apparatus 1, average power control is used. In the average power control, a moving average value of past several samples of the supplied electric power is used as the target amount of electric power, and the electric power supply to the heater 302 is controlled in such a manner that this target amount of electric power is maintained. Note that power control in which electric power is supplied to the heater 302 in such a manner that a previously set amount of electric power (target amount of electric power) is maintained can also be used. In the above-described electric power control, a theoretical value set for the film formation rate based on the kind of film formation material, the relative speed of the substrate and the evaporation source, and the like is used to control the film thickness.

[0067] In the present embodiment, as the basic electric power control method, the above-described rate control (first process) is adopted, and electric power is started to be supplied to the heater 302 (S101). That is, the amount of supplied electric power to the heater 302 (control target temperature) is adjusted in time in such a manner that the monitored value of the film formation rate acquired by the film formation rate monitoring apparatus 1 is maintained at the desired rate.

[0068] At this time, the monitoring value of the film formation rate acquired by the film formation rate monitoring device 1 sometimes becomes an abnormal value deviating from the target rate for some reason. As the reason for the monitoring value taking an abnormal value, in the present embodiment, two reasons are assumed, (1) the film formation material 400 undergoes a sudden boil and (2) the monitoring unit 10 develops a failure, and the present embodiment is characterized by performing control for discriminating the abnormal state of the film formation device 2 described above. When the film formation material 400 in the container 301 undergoes a sudden boil, the attached amount of the film formation material 400 with respect to the crystal oscillator 13a instantaneously / suddenly increases. In addition, as the failure of the monitoring unit 10, there is a case where the attached amount of the film formation material 400 with respect to the crystal oscillator 13 excessively increases, resulting in the monitoring value becoming an abnormal value. Therefore, in the rate control, a threshold value for judging whether the acquired monitoring value represents a value in the abnormal state described above is set, and in the rate control, whether the above judgment is satisfied is confirmed every time the film formation rate is acquired (S102).

[0069] In a case where the acquired film formation rate does not exceed the threshold value (Yes in S102), the rate control is continued (S101), and as long as no abnormal film formation rate is acquired, the rate control is continued until the film formation sequence ends (S103).

[0070] In a case where the acquired film formation rate reaches the threshold value (No in S102), the determination sequence for judging the state of the film formation device 2 is shifted to, and the power control is switched from the rate control to the average power control (second process) (S104). That is, the power is supplied to the heater 302 at a constant power amount. Also, in this state, the rotation control mode of the chopper 12 is changed to a rotation control mode (second chopper mode) different from the rotation control mode (first chopper mode) executed at the time of the rate control (third process) (S105). Specifically, the rotation control of the chopper 12 is changed in such a manner that the length of the period in which the non-chopped state is continued within a prescribed period (a prescribed unit period) is changed, that is, in such a manner that the exposure time of the crystal oscillator 13a within the prescribed period is changed. Also, it is confirmed whether the amount of change (variation) in the resonance frequency of the crystal oscillator 13a within the prescribed period due to the variation in the exposure time within the prescribed period caused by the change in the rotation control of the chopper 12 is an amount of change corresponding to the variation in the exposure time within the prescribed period, that is, whether the amount of variation in the attached amount of the film formation material 400 with respect to the crystal oscillator 13a within the prescribed period represents a value corresponding to the amount of variation in the exposure time within the prescribed period (fourth process) (S106). The state of the film formation device 2 is judged from the amount of variation in the resonance frequency.

[0071] Here, with reference to Figure 5 , the rotation control mode of the chopper 12 of the present embodiment will be described. Figure 5is a graph illustrating the rotation control of the shielding member 12 of the present embodiment, (a) is a graph illustrating the rotation control of the shielding member 12 in the first mode, and (b) is a graph illustrating the rotation control of the shielding member 12 in the second mode. In Figure 5 In the present embodiment, 0 is assigned to a state in which the shielding member 12 shields the crystal oscillator 13, and 1 is assigned to a state in which the shielding member 12 does not shield the crystal oscillator 13.

[0072] The present embodiment is characterized in that the control of the rotation operation of the shielding member 12 is changed in order to determine the state of the film forming apparatus 2. Specifically, the second shielding mode (hereinafter referred to as the second mode) is executed, in which the rotation speed of the shielding member 12 is controlled in such a manner that the exposure time of the crystal oscillator 13a in a prescribed period is longer than the exposure time in the first shielding mode (hereinafter referred to as the first mode) which is the rotation control in the normal rate control.

[0073] In the second mode, the rated rotation speed of the shielding member 12 in the non-shielding state in which the opening slit 12a overlaps with the monitoring opening 11a is controlled to be 1 / 10 of the rated rotation speed in the shielding state in which the opening slit 12a does not overlap with the monitoring opening 11a. In the first mode, the rotation of the shielding member 13 is controlled at a constant rated rotation speed regardless of whether the opening slit 12a is in the shielding state or the non-shielding state with respect to the monitoring opening 11a. The rated rotation speed in the shielding state of the second mode is the same speed as the rated rotation speed in the first mode, and thus the rated rotation speed in the non-shielding state of the second mode is 1 / 10 of the rated rotation speed in the non-shielding state of the first mode. Thus, when compared in the same prescribed period (unit period), the time length (second length) of the period in which the non-shielding state is assumed in the second mode is longer than the time length (first length) of the period in which the non-shielding state is assumed in the first mode.

[0074] Figure 5 In the present embodiment, (a) shows the time length TOl of the period in which the non-shielding state (film-attached state) is assumed in the first mode, and (b) shows the time length TO2 of the period in which the non-shielding state is assumed in the second mode. As shown in Figure 5 by making the rated rotation speed in the non-shielding state of the second mode 1 / 10 of the rated rotation speed in the non-shielding state of the first mode, TO2 becomes 10 times the time of TOl. In Figure 5The number of times that the first mode becomes the non-shading state is three, and the number of times that the second mode becomes the non-shading state is two, so the number of times is greater in the first mode. However, the duration of one non-shading state is longer in the second mode than in the first mode, and the total duration of the non-shading state in the prescribed period is also longer in the second mode than in the first mode.

[0075] In Figure 5 In the example shown, the proportion of the time in the non-shading state per unit time is about 3.3% in the first mode, and about 25% in the second mode.

[0076] The above proportion of about 3.3% in the first mode is a value under constant-speed rotation control, and is therefore a value that coincides with the opening rate of the shading member 12 (the area ratio of the opening portion 12a with respect to the shading portion 12b). That is, in the shading member 12 of the present embodiment, the area ratio of the shading portion 12b to the opening portion 12a is that the opening portion 12a occupies 1 / 30 and the shading portion 12b occupies 29 / 30, and the opening rate of the shading member 12 is 1 / 30 = 3.3%.

[0077] On the other hand, the above proportion of about 25% in the second mode is solved in the following manner. That is, by making the rated rotation speed in the non-shading state 1 / 10 of the rated rotation speed in the shading state, the time in the open state (non-shading state) becomes 1 / 30 ÷ 1 / 10 = 10 / 30 compared to the first mode. On the other hand, the time in the closed state (shading state) is 29 / 30 as in the first mode. Thus, the opening rate = time in the open state ÷ time for one rotation = 10 / 30 ÷ (10 / 30 + 29 / 30) = 10 / 39 = 0.25.

[0078] That is, by the speed control of the shading member 12 (control that makes the rated rotation speed in the non-shading state slower than the rated rotation speed in the shading state) performed by the present embodiment, it is possible to substantially increase the opening rate of the shading member 12. Thus, without taking a method such as physically changing the shape of the shading member 12 (without complicating the structure of the device), it is possible to control the opening rate of the shading member 12 to be variable, and thereby arbitrarily control the film formation amount with respect to the crystal oscillator 13.

[0079] When the rotation control mode of the shielding member 12 is changed, the proportion of the time in the non-shielding state per unit time changes, and the actual opening rate of the shielding member 12 changes. As a result, the amount of deposition of the film formation material 400 with respect to the crystal oscillator 13 in the prescribed period changes, and thus the amount of change in the resonance frequency of the crystal oscillator 13 in the prescribed period also changes. That is, as long as the monitoring unit 10 is normally operating, the change in the length of the period of the non-shielding state of the shielding member 12 in the prescribed period should be reflected as a change in the amount of change in the resonance frequency of the crystal oscillator 13 in the prescribed period. However, in the case where the above-described failure occurs and the monitoring unit 10 does not operate normally, it can become a state where the amount of change in the resonance frequency of the crystal oscillator 13 in the prescribed period does not sufficiently change even if the rotation control of the shielding member 12 is changed, or the amount of change is zero.

[0080] Therefore, in the case where the amount of change in the resonance frequency of the crystal oscillator 13 acquired before and after the change in the rotation control of the shielding member 12 is reflected as a change corresponding to the change in the rotation control of the shielding member 12, it is determined that the cause of the abnormal value of the film formation rate in S102 is the boil-off (YES in S106). For example, the determination is made based on whether or not the acquired amount of change in the resonance frequency falls within a value or a numerical range that is set in advance by experiment or the like as a change in the amount of change in the resonance frequency expected when the monitoring unit 10 is normally operating. In the case where the acquired amount of change in the resonance frequency falls within the prescribed value or the prescribed numerical range, it is determined that the cause of the abnormal value of the film formation rate is the boil-off.

[0081] In this case, boil-off countermeasure control (fifth step) is implemented (S107). In the present embodiment, as the boil-off countermeasure control, control to return to the rate control is performed. Note that the boil-off countermeasure control is not limited to this, and control to interrupt the film formation sequence can be performed depending on the degree or frequency of the boil-off, for example.

[0082] On the other hand, in the case where the amount of change in the resonance frequency of the crystal oscillator 13 acquired before and after the change in the rotation control of the shielding member 12 is not reflected as a change corresponding to the change in the rotation control of the shielding member 12 (NO in S106), it is determined that the monitoring unit 10 has developed some of the above-described failures. For example, in the case where the acquired amount of change in the resonance frequency is not the above-described prescribed value or does not fall within the prescribed numerical range, it is determined that the cause of the abnormal value of the film formation rate is a failure of the monitoring unit 10. Specifically, a case where the amount of change in the resonance frequency of the crystal oscillator 13 after the change in the rotation control of the shielding member 12 (first mode → second mode) is zero or the amount of change is significantly reduced is considered, but the present embodiment is not limited to this.

[0083] In this case, monitoring response control (sixth step) (S108) is implemented. In the present embodiment, as the monitoring response control, control is performed in which the average power control switched in S104 is continued until the end of the film formation sequence (S109). Note that the monitoring response control is not limited to this, and, for example, control can be performed in which the failure of the monitoring unit 10 is reported to the user by interrupting the film formation sequence.

[0084] By the above control, it is appropriately determined whether the abnormal value of the film formation rate is due to the bumping of the film formation material 400 in the evaporation source container 301 or due to the failure of the monitoring unit 10, and thus film formation control can be performed. In addition, the determination of the cause can be performed by simple control achieved by switching based on the power control and the change in the rotation control of the shielding member. In particular, in the case of the failure of the monitoring unit 10, it is difficult to directly confirm the monitoring unit disposed in the vacuum chamber, and confirmation can be performed using the above control, and thus this is very advantageous for shortening the production cycle. That is, according to the present embodiment, film formation control can be performed more accurately and simply by grasping the state of the apparatus.

[0085] The method of the rotation control of the shielding member 12 for confirming the change in the amount of variation in the resonance frequency of the crystal oscillator in a prescribed period is not limited to the above-described control method. For example, it can be a control method in which, in the rotation control of the shielding member 12 in the second mode, the shielding member 12 is reciprocated in such a manner that the rotation direction is temporarily reversed, and thus the number of times (the frequency is increased) of becoming the non-shielding state in the prescribed period is increased. By causing the shielding member 12 to perform reciprocating rotation, the opening slit 12a appears and disappears in the vicinity of the monitoring opening 11a, and thus the number of times of generation of the non-shielding state in the prescribed period can be increased compared to the case in which the non-shielding state is periodically formed by rotating in a single direction. Thus, the total duration of the non-shielding state in the prescribed period can be increased. Note that, from the viewpoint of avoiding film formation unevenness, the reversal of the rotation direction in the reciprocating rotation is preferably performed after the opening slit 12a completely passes through the monitoring opening 11a (that is, after the crystal oscillator 13a becomes a sufficiently shielded state).

[0086] Alternatively, in the second mode, the number of times of the non-shielding state in the prescribed period can be increased by control in which the rated rotation speed in the shielding state is changed to a speed faster than the rated rotation speed in the non-shielding state (the rated rotation speed in the first mode).

[0087] Alternatively, in the second mode, the duration of the non-shielding state in the prescribed period can be increased by temporarily stopping the rotation of the shielding member 12 in the non-shielding state.

[0088] Further, it can be control that combines the above-described controls. For example, it can be control that reduces the rated rotation speed in the non-shielding state and reciprocatingly rotates in a manner that repeats the shielding state and the non-shielding state in a short time.

[0089] In addition, in the present embodiment, the rated rotation speed in the shielding state of the second mode is set to the same speed as the rated rotation speed in the first mode, but can be appropriately set to different speeds within a range in which an effect of substantially increasing the opening ratio of the shielding member 12 can be obtained.

[0090] Symbol explanation:

[0091] 1…film formation rate monitoring device, 10…monitoring unit, 11…crystal monitoring head, 11a…monitoring opening, 12…chopper, 12a…opening slit (opening portion, non-shielding portion), 12b…shielding portion, 13 (13a, 13b)…crystal oscillator, 14…crystal holder (rotary support), 15…servo motor (drive source), 15a…motor shaft, 16…servo motor (drive source), 16a…motor shaft 16a, 17 (17a, 17b)…position (rotation phase) detection mechanism, 18 (18a, 18b)…position (rotation phase) detection mechanism, 19…resonator, 2…film formation device, 100…substrate, 20…control section (acquisition section, heating control section), 200…vacuum chamber (film formation chamber), 300…evaporation source device, 301…evaporation source container (crucible), 302…heater (heating source), 303…nozzle.

Claims

1. A film-forming apparatus, comprising: A chamber that contains the object to be film-formed; A heating control unit controls the power supplied to a heating source for heating a film-forming material contained in a container disposed within the chamber. A monitoring unit, disposed within the chamber, is used to detect the film-forming rate of the film-forming material relative to the film-forming object. The monitoring unit includes a crystal oscillator and a rotating body having a shielding portion and an opening portion and disposed between the crystal oscillator and the container. A rotation control unit controls the rotation of the rotating body to obtain either a shielded state where the shielding part is located between the container and the crystal oscillator, or an unshielded state where the opening part is located between the container and the crystal oscillator; as well as The acquisition unit acquires the film formation rate based on the change in the resonant frequency of the crystal oscillator. The film-forming apparatus is used to form a film made of the film-forming material on the film-forming object, characterized in that, The system includes a state determination unit. If, when the heating control unit maintains a constant power supply to the heating source, the change in the resonant frequency during the specified period (when the rotation control unit changes the rotation speed of the rotating body in a manner that varies the length of the period during which the unshielded state occurs within a specified period) does not fall within a specified range, the state determination unit determines that the monitoring unit has malfunctioned. Conversely, if the change in the resonant frequency during the specified period (when the rotation control unit changes the rotation speed of the rotating body in a manner that varies the length of the period during which the unshielded state occurs within a specified period) falls within a specified range, the state determination unit determines that the film-forming material contained in the container has experienced sudden boiling.

2. The film-forming apparatus according to claim 1, characterized in that, The film formation is performed by rate control, wherein the rate control is the control of the electrical force supplied to the heating source by the heating control unit in a manner that maintains the film formation rate acquired by the acquisition unit at a predetermined value. When the film-forming rate acquired by the acquisition unit exceeds a predetermined threshold, a determination sequence for determining the state of the film-forming apparatus by the state determination unit is executed.

3. The film-forming apparatus according to claim 2, characterized in that, When the film-forming rate acquired by the acquisition unit exceeds a predetermined threshold, the control switches from rate control to power control. The power control is the control by which the heating control unit supplies power to the heating source with an electrical force set independently of the film-forming rate acquired by the acquisition unit.

4. The film-forming apparatus according to claim 1, characterized in that, When the state determination unit determines that the film-forming device is in a state of sudden boiling of the film-forming material contained in the container, the subsequent film formation is performed by rate control. The rate control is the control of the power supplied to the heating source by the heating control unit in a way that maintains the film formation rate acquired by the acquisition unit at a predetermined value.

5. The film-forming apparatus according to claim 1, characterized in that, If the state determination unit determines that the state of the film-forming apparatus is that the monitoring unit has malfunctioned, the subsequent film formation is performed by power control. The power control is the control by which the heating control unit supplies power to the heating source with an electrical force set independently of the film formation rate obtained by the acquisition unit.

6. The film-forming apparatus according to claim 1, characterized in that, have: In the first occlusion mode, the rotation control unit rotates the occlusion unit in such a way that the period during which the unit is in the non-occlusion state within a specified period becomes a first length. as well as In the second occlusion mode, the rotation control unit rotates the occlusion unit such that the period during which the unit is in the non-occlusion state within the predetermined period is a second length longer than the first length. When the heating control unit keeps the power supplied to the heating source constant, the state determination unit determines the state of the film forming apparatus based on the change in the amount of resonant frequency during the specified period when switching from the first shielding mode to the second shielding mode.

7. The film-forming apparatus according to claim 6, characterized in that, In the second occlusion mode, the rotation control unit rotates the occlusion unit in such a way that the rotation speed in the unocclusion state is slower than the rotation speed in the occlusion state.

8. The film-forming apparatus according to claim 6, characterized in that, The rotation control unit rotates the occlusion unit in such a way that the rotation speed in the unocclusion state of the second occlusion mode is slower than the rotation speed in the unocclusion state of the first occlusion mode.

9. The film-forming apparatus according to claim 6, characterized in that, The rotation control unit rotates the occlusion unit back and forth in the second occlusion mode in such a way that the frequency of being in the unoccluded state during the predetermined period in the second occlusion mode is higher than the frequency of being in the unoccluded state during the predetermined period in the first occlusion mode.

10. A method for controlling a film-forming apparatus, wherein, The film-forming apparatus includes: A chamber that contains the object to be film-formed; A heating control unit controls the power supplied to a heating source for heating a film-forming material contained in a container disposed within the chamber. A monitoring unit, disposed within the chamber, is used to detect the film-forming rate of the film-forming material relative to the film-forming object. The monitoring unit includes a crystal oscillator and a rotating body having a shielding portion and an opening portion and disposed between the crystal oscillator and the container. A rotation control unit controls the rotation of the rotating body to obtain either a shielded state where the shielding part is located between the container and the crystal oscillator, or an unshielded state where the opening part is located between the container and the crystal oscillator; as well as The acquisition unit acquires the film formation rate based on the change in the resonant frequency of the crystal oscillator. The film-forming apparatus is used to form a film made of the film-forming material on the film-forming object. The control method for the film-forming apparatus is characterized by comprising: In the first step, the film formation is performed by rate control, wherein the rate control is the control of the electrical force supplied to the heating source by the heating control unit in such a way as to maintain the film formation rate acquired by the acquisition unit at a predetermined value; In the second step, when the film-forming rate acquired by the acquisition unit exceeds a predetermined threshold, the film-forming process is switched from rate control to power control. The power control is the control by which the heating control unit supplies power to the heating source with an electrical force set independently of the film-forming rate acquired by the acquisition unit. The third step is a step in which the rotation control unit varies the rotational speed of the rotating body by changing the length of the period during which the unshielded state is within a predetermined period during the second step; and In the fourth step, if the amount of change in the resonant frequency during the specified period when the rotation speed is changed in the third step is not the amount of change corresponding to the length change of the period during which the unshielded state is in the specified period, or if it does not fall within the specified range, it is determined that the monitoring unit has malfunctioned.

11. The control method for the film-forming apparatus according to claim 10, characterized in that, It also includes continuing the sixth step of film formation via the power control when the status of the film-forming device is determined to be a fault in the monitoring unit during the fourth step.

12. The control method for the film-forming apparatus according to claim 10, characterized in that, The film-forming device has: In the first occlusion mode, the rotation control unit rotates the occlusion unit in such a way that the period during which the unit is in the non-occlusion state within a specified period becomes a first length. as well as In the second occlusion mode, the rotation control unit rotates the occlusion unit such that the period during which the unit is in the non-occlusion state within the predetermined period is a second length longer than the first length. In the first process, the first occlusion mode is executed. In the third step, the process switches from the first masking mode to the second masking mode.

13. The control method for the film-forming apparatus according to claim 12, characterized in that, In the second occlusion mode, the rotation control unit rotates the occlusion unit in such a way that the rotation speed in the unocclusion state is slower than the rotation speed in the occlusion state.

14. The control method for the film-forming apparatus according to claim 12, characterized in that, The rotation control unit rotates the occlusion unit in such a way that the rotation speed in the unocclusion state of the second occlusion mode is slower than the rotation speed in the unocclusion state of the first occlusion mode.

15. The control method for the film-forming apparatus according to claim 12, characterized in that, The rotation control unit rotates the occlusion unit back and forth in the second occlusion mode in such a way that the frequency of being in the unoccluded state during the predetermined period in the second occlusion mode is higher than the frequency of being in the unoccluded state during the predetermined period in the first occlusion mode.

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