Control apparatus, control method, and storage medium

Abstract

To effectively suppress the adhesion of splashes to a material to be vapor-deposited in a vacuum vapor deposition system without additional equipment.SOLUTION: A control device for controlling a voltage source connected to a vapor deposition boat in a vapor deposition system and controlling a current flowing through a vapor deposition material contained in the vapor deposition boat, the control device comprising: a supplied vapor deposition material accumulated amount calculation unit configured to calculate an accumulated amount of a vapor deposition material supplied to the vapor deposition boat; A control device comprising: an appropriate current value specifying unit configured to specify an appropriate current value based on a correspondence relationship between a current value measured by an ammeter and an integrated amount of a supply amount of an evaporation material E m when a supply amount of the evaporation material per unit time is equal to an evaporation amount thereof, and the calculated integrated amount; a current value acquiring unit configured to acquire a current value flowing through the evaporation material accommodated in the evaporation boat; and a voltage source control unit configured to control the voltage source based on the current value specified by the appropriate current value specifying unit and the current value acquired by the current value acquiring unit.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a control device, a control method, and a program. [Background technology]

[0002] Patent Document 1 discloses a vacuum deposition system using an evaporation boat. The evaporation boat includes a boat body having a storage area for the evaporation material and electrode mounting plate portions that protrude outward from the upper end of the boat body. The two electrode mounting plate portions are held (sandwiched) by a pair of upper and lower electrode plates, respectively, and is installed in a vacuum chamber. When evaporating onto an object to be evaporated in a vacuum chamber under a vacuum atmosphere, the boat body is heated by Joule heat by passing electricity between the two electrode mounting plate portions via the electrode plates from a power source. Then, a wire-shaped evaporation material made of a metal, such as copper or aluminum, is supplied from above the bottom plate of the boat body that defines the storage area so that it abuts against the bottom plate. The evaporation material then melts and spreads within the storage area, evaporating from the surface of the molten metal. The evaporated evaporation material adheres to the object to be evaporated, resulting in the evaporation of the evaporation material onto the object.

[0003] It is known that the amount of molten metal fluctuates during evaporation of the deposition material. Such fluctuations in the amount of molten metal increase the amount of splash adhering to the deposition target, potentially reducing product yield. "Splash" refers to, for example, the material that remains liquid and splashes from the surface of the molten metal and adheres to the deposition target without evaporating due to bumping. Typically, users of vacuum deposition equipment periodically visually check the amount of molten metal and, based on their own experience, adjust the electrical characteristics (power, voltage, current, resistance, etc.) or the supply rate of the wire-shaped deposition material to the storage unit to prevent splash. For example, it has been proposed to install an imaging device, such as a camera, to capture images of the deposition boat during deposition and analyze the captured images to control the electrical characteristics and supply rate (see Patent Document 2). However, this approach increases the number of parts, resulting in higher costs. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-046106 [Patent Document 2] Special Publication No. 2022-507610 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide a control device, a control method, and a program that effectively suppress the adhesion of splashes to a deposition target in a vacuum deposition system without using any additional equipment. [Means for solving the problem]

[0006] One aspect of the present invention is a control device that controls a voltage source connected to a vapor deposition boat in a vacuum vapor deposition system and controls a current flowing through a vapor deposition material contained in the vapor deposition boat. The control device includes: a supplied vapor deposition material integrated amount calculation unit that calculates an integrated amount of the vapor deposition material supplied to the vapor deposition boat; an appropriate current value identification unit that determines a correspondence relationship between a current value measured by an ammeter and an integrated amount of the supplied amount of the vapor deposition material Em when the amount of the vapor deposition material is appropriate and the supplied amount and evaporation rate per hour are equal; and that identifies an appropriate current value based on the calculated integrated amount; a current value acquisition unit that acquires a current value flowing through the vapor deposition material contained in the vapor deposition boat; and a voltage source control unit that controls the voltage source based on the current value identified by the appropriate current value identification unit and the current value acquired by the current value acquisition unit. [Effects of the Invention]

[0007] According to the present invention, splash adhesion to a deposition target in a vacuum deposition system can be effectively suppressed without the need for additional equipment. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram showing the configuration of a vacuum deposition system ES according to the present embodiment. [Figure 2] 1 is a diagram illustrating an example of the configuration of a control device 10 according to the present embodiment. [Figure 3] 4 is a flowchart showing the operation of the control device 10 according to the present embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing the configuration of a vacuum deposition system ES according to this embodiment. The vacuum deposition system ES is a system that deposits an evaporated deposition material Em on one side of a deposition target Sw. The deposition target Sw is, for example, a sheet-shaped substrate. The deposition material Em is, for example, aluminum formed into a wire shape. The deposition material Em is supplied into a vacuum chamber in a vacuum atmosphere and evaporated, thereby depositing the evaporated deposition material Em on one side of the deposition target Sw. Hereinafter, terms indicating directions such as up and down are based on FIG. 1, which shows the installation position of the apparatus.

[0010] The vacuum deposition system ES is a type called a winding type, and includes a vacuum chamber 1. A vacuum pump unit Pu, which is composed of a turbo molecular pump, a rotary pump, or the like, is connected to the vacuum chamber 1 via an exhaust pipe Ep, and a vacuum atmosphere (for example, 10 -5 Pa) is formed.

[0011] The vacuum chamber 1 is divided into two compartments, an upper compartment and an lower compartment, by a partition plate 11. A transport unit 2 that transports the sheet-like substrate Sw at a constant speed is disposed in the upper transport chamber Ts. The transport unit 2 includes a payout roller 21, around which the sheet-like substrate Sw is wound in advance, and which is driven to rotate by a motor 21a to pay out the sheet-like substrate Sw at a constant traveling speed, and a take-up roller 22 that is driven to rotate by a motor 22a to take up the sheet-like substrate Sw after the film formation. A can roller Cr is disposed inside an opening 12 formed in the partition plate 11, facing a deposition boat 3 (described later), around which a portion of the sheet-like substrate Sw is wound. The transport chamber Ts is also appropriately provided with a plurality of guide rollers Gr. The guide roller Gr guides the sheet-like substrate Sw fed from the payout roller 21 to the can roller Cr, or guides the film-formed sheet-like substrate Sw from the can roller Cr to the take-up roller 22.

[0012] In the deposition chamber Vs located on the lower side, a deposition boat 3 is placed as a deposition source to deposit a deposition material Em onto one surface of the substrate Sw wound around the can roller Cr.

[0013] The evaporation boat 3 includes a boat body 31 and an electrode mounting plate 32. The boat body 31 has a recess 31a with a flat bottom that serves as a storage section for the evaporation material Em. The electrode mounting plate 32 extends horizontally outward from both longitudinal ends (left-right direction in FIG. 1 ) of the boat body 31. The evaporation boat 3 is integrally formed by pressing a metal plate having a higher melting point than the evaporation material Em. Examples of high-melting-point metals include boron nitride, molybdenum, tungsten, and tantalum. Two support bases 4, 4 made of an insulating material and spaced apart in the longitudinal direction are installed on the inner surface 1a of the lower wall of the vacuum chamber 1. A pair of upper and lower electrode plates 5a, 5b made of a highly conductive metal such as copper are attached to the upper surfaces of the support bases 4, 4, respectively. The electrode plates 5a, 5b are detachably attached to the evaporation boat 3 by fastening means 41 such as bolts while sandwiching the electrode mounting plate portions 32, 32 from above and below.

[0014] When the electrode plates 5a, 5b holding the electrode mounting plates 32, 32 are attached, the evaporation boat 3 is installed at a predetermined height from the inner surface 1a of the lower wall of the vacuum chamber, with the bottom plate of the boat body 31, which defines the recess 31a, horizontal. A voltage source Ps is connected to each of the electrode plates 5a, 5b. The boat body 31 can be heated by Joule heat by applying a voltage between the electrode mounting plates 32, 32 via the electrode plates 5a, 5b. An ammeter Am is provided in the electrical circuit between the voltage source Ps and the electrode mounting plates 32, 32, so that the current value when the voltage is applied can be measured. The evaporation chamber Vs is equipped with a material supply unit 6 for continuously or intermittently supplying wire-shaped evaporation material Em to the recess 31a of the boat body 31.

[0015] The material supply unit 6 includes a feed roller 61 installed on the side of the deposition prevention plate 13 arranged in the deposition chamber Vs facing away from the deposition boat 3, a motor 62 that rotates and drives the feed roller 61, and a pair of upper and lower guide rollers 63, 63. A through hole 13a is provided at a predetermined position in the deposition prevention plate 13, through which a wire-shaped deposition material Em is inserted. A guide tube 64 of a predetermined length with its tip bent downward is attached to the surface of the deposition prevention plate 13 facing the deposition boat 3 so as to surround the through hole 13a, and guides the deposition material Em toward the recess 31a of the boat body 31. The deposition material Em is formed to an outer diameter of 1 mm to 5 mm and is wound around the feed roller 61 in advance.

[0016] The vacuum deposition system ES includes a control device 10. The control device 10 controls the overall operation of moving parts such as the vacuum pump Pu, motors 21a and 21b, motor 62 of the material supply unit 6, and voltage source Ps. A current value measured by an ammeter Am is input to the control device 10, and the voltage source Ps is controlled based on this. A vacuum deposition method using the vacuum deposition system ES is described below.

[0017] When an aluminum film is deposited on a sheet-like substrate Sw in a vacuum chamber 1 under a vacuum atmosphere using the vacuum deposition system ES (i.e., the vacuum deposition method of this embodiment), the boat body 31 is heated by Joule heat by applying current between the electrode mounting plates 32, 32 via the electrode plates 5a, 5b using a voltage source Ps. After a predetermined time has elapsed, the motor 62 rotates the feed roller 61 to feed out the wire-like deposition material Em at a predetermined speed. As a result, the tip Em1 of the deposition material Em abutting the bottom plate of the boat body 31 that defines the storage section 31a gradually melts and spreads, and the deposition material Em on the wetted and spread surface evaporates. Simultaneously, the motors 21a, 22a of the transport unit 2 are rotated to feed out the sheet-like substrate Sw at a constant traveling speed. As a result, the evaporated deposition material Em adheres to the portion of the sheet-like substrate Sw wrapped around the can roller Cr, thereby depositing an aluminum film. The deposition rate at this time is set in the range of, for example, 200 mm / min to 2000 mm / min.

[0018] When depositing the deposition material Em on the sheet-like substrate Sw as described above, the amount of deposition material Em supplied per hour and the voltage of the voltage source Ps are initially set so that the amount of deposition material Em supplied per hour equals the amount of evaporation. However, when the amount of deposition material Em supplied per hour and the voltage of the voltage source Ps are set so that the amount of material supplied equals the amount of evaporation while maintaining an appropriate amount of molten metal, a phenomenon has been observed in which the current measured by the ammeter Am increases over time. In other words, if the amount of molten metal is excessive relative to the appropriate amount, the electrical resistance value drops below a predetermined value, and conversely, if it is insufficient, the electrical resistance value increases. However, a phenomenon has been observed in which this appropriate electrical resistance value varies depending on the cumulative amount of material supplied. According to the inventors' extensive research, the increase in the current measured by the ammeter Am over time is believed to be due to electrical changes occurring, for example, at the interface between the boat body 31 and the molten deposition material Em, depending on the heating history, as the deposition material Em is continuously supplied.

[0019] The evaporation of the evaporation material Em causes an electrical change at the interface between the boat body 31 and the molten evaporation material Em. Therefore, in order to maintain a state in which the supply amount and evaporation amount of the evaporation material Em per unit time are equal, it has been discovered that it is necessary to consider not only the supply amount of the evaporation material Em per unit time and the voltage of the voltage source Ps but also the cumulative amount of evaporation of the evaporation material Em.

[0020] Furthermore, assuming that the amount of molten vapor deposition material Em is maintained at a substantially constant level, the cumulative amount of evaporation of vapor deposition material Em and the cumulative amount of supply of vapor deposition material Em are substantially equal, and the cumulative amount of evaporation of vapor deposition material Em can be replaced by the cumulative amount of supply of vapor deposition material Em.

[0021] FIG. 2 is a diagram illustrating an example of the configuration of the control device 10 according to the present embodiment. The control device 10 includes a supplied vapor deposition material integrated amount calculation unit 110, an appropriate current value identification unit 120, a current value acquisition unit 130, a voltage source control unit 140, and a storage unit 190. The storage unit 190 stores an integrated current amount correspondence relationship 191. The integrated current amount correspondence relationship 191 is a correspondence relationship between a current value measured by an ammeter Am and an integrated amount of the supplied amount of the vapor deposition material Em when the amount of the vapor deposition material Em is appropriate and the supply amount and evaporation amount per hour of the vapor deposition material Em are equal. The integrated current amount correspondence relationship 191 is calculated in advance and stored in the storage unit 190. The integrated current amount correspondence relationship 191 is a function that outputs a current value measured by the ammeter Am using, for example, the integrated amount of the supplied amount of the vapor deposition material Em as a variable. The current accumulated amount correspondence relationship 191 is a table in which, for example, a current value measured by an ammeter Am corresponds to an accumulated amount of the supply amount of the vapor deposition material Em. That is, the current accumulated amount correspondence relationship 191 may be a continuous correspondence relationship or a discrete correspondence relationship.

[0022] The supply evaporation material integrated amount calculation unit 110 calculates the integrated amount of the evaporation material Em supplied to the evaporation boat 3. The supply evaporation material integrated amount calculation unit 110 calculates the integrated amount of the evaporation material Em, for example, based on the rotation speed of the delivery roller 61 or the motor 62. When the amount of the evaporation material Em supplied per hour to the evaporation boat 3 is constant, the supply evaporation material integrated amount calculation unit 110 may calculate the integrated amount of the evaporation material Em supplied to the evaporation boat 3 based on the elapsed time from the time when the supply of the evaporation material Em to the evaporation boat 3 started and the amount of the evaporation material Em supplied per hour.

[0023] The supplied evaporation material integrated amount calculation unit 110 records the calculated integrated amount of the evaporation material Em in the storage unit 190 as the supplied evaporation material integrated amount 192. The supplied evaporation material integrated amount calculation unit 110 may calculate the amount of the evaporation material Em supplied to the evaporation boat 3 in a certain time period, and add the calculated amount to the supplied evaporation material integrated amount 192 to update the amount, thereby calculating the integrated amount of the evaporation material Em supplied to the evaporation boat 3.

[0024] The appropriate current value specifying unit 120 specifies a current value corresponding to the calculated integrated amount of the vapor deposition material Em from the current integrated amount correspondence relationship 191.

[0025] The current value acquisition unit 130 acquires the current value measured by the ammeter Am.

[0026] The voltage source control unit 140 controls the voltage of the voltage source Ps based on the current value identified by the appropriate current value identifying unit 120 and the current value acquired by the current value acquiring unit 130. When the current value identified by the appropriate current value identifying unit 120 is greater than the current value acquired by the current value acquiring unit 130, the voltage source control unit 140 increases the voltage of the voltage source Ps to increase the current value flowing through the molten metal of the deposition material Em. When the current value identified by the appropriate current value identifying unit 120 is smaller than the current value acquired by the current value acquiring unit 130, the voltage source control unit 140 decreases the voltage of the voltage source Ps to decrease the current value flowing through the molten metal of the deposition material Em.

[0027] 3 is a flowchart showing the operation of the control device 10 according to this embodiment. The supplied vapor deposition material integrated amount calculation unit 110 calculates the integrated amount of the vapor deposition material Em supplied to the vapor deposition boat 3 (step S11). The appropriate current value identification unit 120 identifies a current value corresponding to the calculated integrated amount of the vapor deposition material Em from the current integrated amount correspondence relationship 191 (step S12). The current value acquisition unit 130 acquires a current value measured by the ammeter Am (step S13). The voltage source control unit 140 controls the voltage of the voltage source Ps based on the current value identified by the appropriate current value identification unit 120 and the current value acquired by the current value acquisition unit 130 (step S14).

[0028] The control device 10 adjusts the voltage of the voltage source Ps by repeating the operations from step S11 to step S14.

[0029] Even in a conventional vacuum deposition system ES, it is possible to control the voltage source and calculate the amount of deposition material Em supplied from the material supply unit 6. Therefore, the control device 10 according to this embodiment can be realized in the control device of a conventional vacuum deposition system ES, and no additional equipment is required.

[0030] In addition, in this embodiment, the control device 10 controls the voltage source Ps taking into account the cumulative amount of evaporation of the evaporation material Em, thereby being able to deal with the phenomenon in which the current measured by the ammeter Am increases over time, thereby enabling more appropriate control.

[0031] In the present embodiment, the control device 10 may include a material supply unit control unit 150. The material supply unit control unit 150 controls the material supply unit 6 based on the current value identified by the appropriate current value identifying unit 120 and the current value acquired by the current value acquiring unit 130, thereby controlling the amount of vapor deposition material Em to be supplied. For example, if the current value identified by the appropriate current value identifying unit 120 is greater than the current value acquired by the current value acquiring unit 130, the amount of molten metal is determined to be insufficient (the amount of evaporation is excessive), and the material supply unit control unit 150 controls the material supply unit 6 to increase the supply of material. Furthermore, the voltage source control unit 140 and the material supply unit control unit 150 may simultaneously control the voltage source Ps and the material supply unit 6.

[0032] Other Embodiments One embodiment of the present invention has been described in detail above with reference to the drawings, but the specific configuration is not limited to that described above, and various design changes and the like are possible within the scope that does not deviate from the gist of the present invention.

[0033] The processing of the control device 10 in the above-described embodiment may be implemented by a computer using software. In this case, a program for implementing the functions may be recorded on a computer-readable recording medium, and the program may be loaded into a computer system and executed. The term "computer system" as used herein includes hardware such as an operating system (OS) and peripheral devices. The term "computer-readable recording medium" refers to portable media such as flexible disks, optical magnetic disks, ROMs, and CD-ROMs, as well as storage devices such as hard disks built into a computer system. The term "computer-readable recording medium" may also include media that dynamically store programs for a short period of time, such as communication lines used when transmitting programs over a network such as the Internet or a telephone line, or media that store programs for a fixed period of time, such as volatile memory within a computer system serving as a server or client. The program may be a program that implements only a portion of the functions described above, or may be a program that can implement the functions in combination with a program already stored in the computer system, or may be implemented using a programmable logic device such as an FPGA (Field Programmable Gate Array). [Explanation of symbols]

[0034] ES vacuum deposition system, Em wire-shaped deposition material, Em1 tip of deposition material, Ps voltage source, Sw sheet-shaped substrate (subject to deposition), 1 vacuum chamber, 3 deposition boat, 31 boat body, 31a recess (deposition material storage section), 6 material supply unit, Am ammeter (detection means), 10 control device, 110 supply deposition material integrated amount calculation section, 120 appropriate current value identification section, 130 current value acquisition section, 140 voltage source control section, 190 memory section, 191 current integrated amount correspondence relationship, 192 supply deposition material integrated amount

Claims

1. A control device for controlling a voltage source connected to a deposition boat in a vacuum deposition system and controlling a current flowing through a deposition material contained in the deposition boat, the control device comprising: a supply evaporation material integrated amount calculation unit that calculates an integrated amount of the evaporation material to be supplied to the evaporation boat; an appropriate current value specifying unit that specifies an appropriate current value based on a correspondence relationship between a current value measured by an ammeter and an integrated amount of the supply amount of the deposition material when the amount of the deposition material is appropriate and the supply amount and evaporation amount per hour of the deposition material are equal, and the calculated integrated amount; a current value acquiring unit that acquires a value of a current flowing through the evaporation material contained in the evaporation boat; a voltage source control unit that controls the voltage source based on the current value identified by the appropriate current value identifying unit and the current value acquired by the current value acquiring unit; A control device comprising:

2. a material supply unit control unit that controls an amount of the evaporation material supplied to the evaporation boat, based on the current value specified by the appropriate current value specifying unit and the current value acquired by the current value acquiring unit; The control device of claim 1 further comprising:

3. 1. A control method for controlling a voltage source connected to a deposition boat in a vacuum deposition system, and controlling a current flowing through a deposition material contained in the deposition boat, the method comprising: a supply evaporation material integrated amount calculation step of calculating an integrated amount of the evaporation material supplied to the evaporation boat; an appropriate current value specifying step of specifying an appropriate current value based on a correspondence relationship between a current value measured by an ammeter and an integrated amount of the supply amount of the deposition material when the amount of the deposition material is appropriate and the supply amount and evaporation amount per hour of the deposition material are equal, and the calculated integrated amount; a current value acquiring step of acquiring a current value flowing through the evaporation material contained in the evaporation boat; a voltage source control step of controlling the voltage source based on the current value identified in the appropriate current value identifying step and the current value acquired in the current value acquiring step; A control method comprising:

4. A program for causing a computer to execute the control method according to claim 3.

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