A control method for magnetron sputtering coating equipment

Abstract

The present invention relates to the field of coating equipment control technology, and specifically to a control method for magnetron sputtering coating equipment, including real-time detection of whether a carrier enters a chamber through a chamber entry sensor; when a carrier enters the chamber, recording the rotation position of the motor shaft that drives the carrier to move, and the number of rotations of the rotation position is recorded as 0; when it is detected that the number of rotations of the motor continues to work reaches a predetermined number of rotations, controlling the speed of the motor to decrease, so that the carrier performs deceleration movement, and reducing the movement speed of the carrier; detecting the carrier with reduced movement speed through a stop sensor, when the carrier with reduced movement speed is detected, controlling the carrier to stop movement. The present invention can decelerate the movement of the carrier in advance by setting reasonable parameter values, so as to ensure that the carrier stops stably and accurately at the required position, and avoid the offset of the silicon wafer and the overshoot of the carrier.

Description

Technical Field

[0001] The present invention relates to the technical field of coating equipment control, and in particular to a control method of magnetron sputtering coating equipment. Background Art

[0002] In the prior art, the PLC program of the magnetron sputtering coating equipment has the following problems: the carrier in the chamber relies on the stop sensor to change from a high-speed moving state to a stopped state. When the carrier senses the stop sensor, it starts to decelerate. If the deceleration is too large at this time, the battery silicon wafer will shift on the carrier due to inertia, resulting in coating shift during subsequent coating, which affects the coating process effect and produces defective products. If the deceleration is reduced to avoid the inertial offset problem of the silicon wafer, the carrier will decelerate too far and overshoot will occur. In short, it is difficult to accurately control the position of the carrier in the chamber, especially if the length of the carrier changes, it will be even more difficult to control. The prior art has insufficient control capabilities and lacks flexibility, and cannot respond to flexible changes in the length of the carrier. Summary of the invention

[0003] In view of this, the purpose of the present invention is to propose a control method for magnetron sputtering coating equipment to solve the problem that it is difficult to accurately control the stop position of the carrier in the chamber in the prior art, and it is even more difficult to control if the length of the carrier changes.

[0004] Based on the above purpose, the present invention provides a control method for magnetron sputtering coating equipment, comprising the following steps:

[0005] The cavity entry sensor is used to detect in real time whether a carrier board has entered the cavity;

[0006] When it is detected that a carrier plate enters the chamber, the rotation position of the motor shaft driving the carrier plate is recorded, and the number of revolutions of the rotation position is recorded as 0;

[0007] When it is detected that the number of revolutions of the motor continues to work reaches a predetermined number, the speed of the motor is controlled to decrease, so that the carrier plate performs a deceleration movement, thereby reducing the movement speed of the carrier plate;

[0008] The carrier plate whose moving speed is reduced is detected by a stop sensor, and when the carrier plate whose moving speed is reduced is detected, the carrier plate is controlled to stop moving.

[0009] Optionally, the predetermined number of laps is obtained by the following steps:

[0010] Obtain the maximum deceleration a to ensure that the silicon wafer in the carrier does not deviate;

[0011] The deceleration stop time t is calculated by formula 1 1

[0012] S = -0.5at 1 2 (I)

[0013] Where S is the deceleration stop distance, representing the distance between the stop sensor and the next chamber valve; the magnitude of the moving speed v after the moving speed of the carrier board is reduced is obtained by calculating with Equation 2

[0014] v = at 1 (II)

[0015] Obtain the speed V of the carrier board moving at a constant speed, and obtain the deceleration time t by calculating with Equation 3 2

[0016] V - v = at 2 (III)

[0017] Obtain the distance L1 that the carrier board moves from speed V to speed v by calculating with Equation 4

[0018] L1 = Vt 2 +(at 2 2 ) / 2 (IV)

[0019] Subtract the distance L1 from the distance between the in - chamber sensor and the stop sensor to obtain the distance L2 between when the carrier board is detected by the in - chamber sensor and when it starts to decelerate.

[0020] Based on the distance L2, convert to obtain the predetermined number of turns of the motor operation.

[0021] Optionally, the method further includes:

[0022] Set the left margin of the carrier board animation at the upper computer display bar, and use this left margin as the starting position of the carrier board animation;

[0023] Real - time detect whether there is a carrier board entering the chamber through the in - chamber sensor. When it is detected that there is a carrier board entering the chamber, start to display the carrier board animation at the starting position on the upper computer display bar;

[0024] Obtain the real - time position of the motor by using the encoder. When the in - chamber sensor senses the carrier board, record the position of the motor as the in - chamber starting position. When the carrier board continues to move, subtract the in - chamber starting position from the real - time position, and then convert it into the moving distance of the animation according to a predetermined ratio, so as to realize the animation following function, which can make the carrier board animation reflect the actual position state of the carrier board in the chamber. At the same time, receive the carrier board information transmitted from an external device and display it on the carrier board animation;

[0025] When the cavity entry sensor detects that the carrier moves into the next cavity, the carrier animation in the previous cavity is set to invisible, the carrier animation in the next cavity is set to visible, and the carrier information is transmitted to the carrier animation in the next cavity for display.

[0026] Optionally, the receiving of the carrier board information transmitted by the external device and displaying it on the carrier board animation includes:

[0027] The external device is an automatic loading device, which is connected to the magnetron sputtering coating device through EIP communication, and is used to automatically complete the carrier loading process and generate carrier information in real time;

[0028] Receive the carrier information transmitted by the automatic loading equipment and display it on the carrier animation.

[0029] Optionally, the carrier information includes a carrier ID and whether the carrier has a silicon wafer.

[0030] Optionally, the method further includes:

[0031] Check the carrier information of all carriers in the magnetron sputtering coating equipment in real time. If the animation of a carrier is in the display state, and the carrier information shows that there is no silicon wafer on the carrier, the carrier is determined to be an empty carrier. If all carriers are empty, the equipment is in a no-material state, and the no-material state time is accumulated;

[0032] When the time of the material-free state reaches the set value, the DC power output is reduced and the use and emission of process gases are reduced. When the carrier information is detected to show that there are silicon wafers on the carrier and they enter the chamber, the DC power output and the use and emission of process gases are restored to the initial values.

[0033] When the method is used for coating, the cavity entry sensor is used to detect in real time whether a carrier plate enters the chamber. When it is detected that a carrier plate enters the chamber, the rotation position of the motor that drives the carrier plate to move is recorded, and the number of rotations of the rotation position is recorded as 0. At the same time, the motor continues to work to drive the carrier plate to move. When it is detected that the number of rotations of the motor continues to work reaches a predetermined number of rotations, it means that the carrier plate has moved a predetermined distance. At this time, the rotation speed of the motor is controlled to be reduced, so that the carrier plate performs a deceleration movement, and the movement speed of the carrier plate is reduced. The carrier plate with reduced movement speed is detected by the stop sensor. When the carrier plate with reduced movement speed is detected, the carrier plate is controlled to stop moving.

[0034] From the above, it can be seen that the method decelerates the carrier in advance by recording the movement distance of the carrier. This method does not rely on external sensors. By setting reasonable parameter values, the movement of the carrier can be decelerated in advance, which can ensure that the carrier stops stably and accurately at the required position, and avoids the offset of the silicon wafer and the overshoot of the carrier, and will not be affected by the change of the length of the carrier. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only for the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0036] Figure 1 The figure is a flow chart of a control method according to an embodiment of the present invention. DETAILED DESCRIPTION

[0037] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below in conjunction with specific embodiments.

[0038] It should be noted that, unless otherwise defined, the technical terms or scientific terms used in the present invention should be understood by people with ordinary skills in the field to which the present invention belongs. The "first", "second" and similar words used in the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. "Include" or "comprise" and similar words mean that the elements or objects appearing before the word include the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connect" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0039] like Figure 1 As shown, a control method for magnetron sputtering coating equipment comprises the following steps:

[0040] S1: Use the cavity entry sensor to detect in real time whether there is a carrier entering the cavity;

[0041] S2: When it is detected that a carrier plate enters the chamber, the rotation position of the motor shaft driving the carrier plate is recorded, and the number of rotations of the rotation position is recorded as 0;

[0042] S3: When it is detected that the number of revolutions of the motor continues to work reaches a predetermined number, the speed of the motor is controlled to decrease, so that the carrier plate performs a deceleration movement, thereby reducing the movement speed of the carrier plate;

[0043] S4: detecting the carrier whose moving speed is reduced by a stop sensor, and when the carrier whose moving speed is reduced is detected, controlling the carrier to stop moving.

[0044] When coating is carried out by using this method, it is detected in real time by a chamber entry sensor whether a carrier plate enters the chamber. When it is detected that a carrier plate enters the chamber, the rotation position of the motor driving the movement of the carrier plate is recorded. The number of rotation cycles of this rotation position is recorded as 0. At the same time, the motor continues to work to drive the movement of the carrier plate. When it is detected that the number of rotation cycles of the continuous rotation of the motor reaches a predetermined number of cycles, it indicates that the carrier plate has moved a predetermined distance at this time. At this time, the rotation speed of the motor is controlled to decrease, so that the carrier plate makes a decelerating movement, reducing the movement speed of the carrier plate. The carrier plate with the reduced movement speed is detected by a stop sensor. When the carrier plate with the reduced movement speed is detected, the carrier plate is controlled to make a stop movement.

[0045] As can be seen from the above, by recording the movement distance of the carrier plate, the carrier plate is decelerated in advance. This method does not rely on external sensors. By setting reasonable parameter values, the carrier plate can be decelerated in advance in its movement, which can ensure that the carrier plate stops stably and accurately at the required position and avoid the deviation of the silicon wafer and the overshoot of the carrier plate.

[0046] In some embodiments, the predetermined number of cycles is obtained through the following steps:

[0047] Obtain the maximum deceleration a that ensures that the silicon wafer in the carrier plate does not deviate. The maximum deceleration a can be obtained through testing. For example, first set a relatively small deceleration to ensure that when the carrier plate decelerates and stops, the silicon wafer in the carrier plate does not deviate. Then gradually increase the deceleration and test the movement state of the carrier plate again until a maximum deceleration a that ensures that the silicon wafer in the carrier plate does not deviate is obtained.

[0048] The deceleration stop time t is obtained by calculating through formula (1) 1

[0049] S = -0.5at² (1) 1 2(1)

[0050] where S is the deceleration stop distance, representing the distance between the stop sensor and the next-stage chamber valve; the magnitude v of the movement speed after the movement speed of the carrier plate is reduced is obtained by calculating through formula (2)

[0051] v = at (2) 1 (2)

[0052] Obtain the speed V of the uniform movement of the carrier plate. This value of the speed V is set by the host computer. The deceleration time t is obtained by calculating through formula (3) 2

[0053] V - v = at (3) 2 (3)

[0054] The distance L1 that the carrier plate moves from the speed V to the speed v during deceleration is obtained by calculating through formula (4)

[0055] L1=Vt 2 +(at 2 2 ) / 2(Thursday)

[0056] Subtract the distance L1 from the distance between the cavity entry sensor and the stop sensor to obtain the distance L2 from when the carrier is detected by the cavity entry sensor to when it starts to decelerate.

[0057] Based on the distance L2, the predetermined number of revolutions of the motor is obtained by conversion. Specifically, the distance L3 that the carrier moves when the motor rotates one revolution can be tested in advance, and the predetermined number of revolutions of the motor is obtained by calculation through L2 / L3.

[0058] In the existing algorithm, the carrier animation logic is written in a stack manner. There are at most several carriers in the chamber, and several carrier object variables are placed in the queue. This method is extremely unstable, especially when the device switches from automatic state to manual state, and the carrier enters and exits the chamber manually, the information in the queue will change, thereby causing BUGs. In long-term operation, the stable operation of the carrier animation cannot be guaranteed, and the carrier animation will be lost or disordered. The disordered information will directly affect the staff's monitoring of the carrier status in the chamber and affect the statistical recording of data. In order to solve this problem, in some embodiments, the method further includes:

[0059] Set the left margin of the carrier animation in the upper computer display bar, and use the left margin as the starting position of the carrier animation;

[0060] The cavity entry sensor is used to detect in real time whether a carrier board has entered the cavity. When it is detected that a carrier board has entered the cavity, the carrier board animation of the carrier board is displayed at the starting position of the display bar of the host computer;

[0061] The encoder is used to obtain the real-time position of the motor. The Trigger function is used to record the position of the motor when the cavity sensor senses the carrier. This position is called the cavity start position. When the carrier continues to move, the real-time position is subtracted from the cavity start position, and then converted into the moving distance of the animation according to a predetermined ratio. This can realize the animation following function, which allows the carrier animation to reflect the actual position of the carrier in the chamber. At the same time, the carrier information received from the external device is displayed on the carrier animation.

[0062] When the cavity entry sensor detects that the carrier moves into the next cavity, the carrier animation in the previous cavity is set to invisible, the carrier animation in the next cavity is set to visible, and the carrier information is transmitted to the carrier animation in the next cavity for display.

[0063] In order to achieve the reliability and stability of the animation, this method adopts the object-oriented idea and no longer uses the queue algorithm. Instead, a carrier animation is made for each chamber. The movement of the carrier is determined by the sensors and whether the motors of the front and rear chambers are in motion. Regardless of the manual or automatic mode, the normal use of the carrier animation can be guaranteed. Each chamber has several sensors, which are arranged on both sides of the chamber. A carrier animation is drawn in each chamber by the host computer. The carrier information can be displayed on these carrier animations. This method avoids the errors caused by the long-term operation of the algorithm and allows the animation to respond to the status of the sensor in real time, which is stable and reliable.

[0064] In some embodiments, receiving the carrier board information transmitted by the external device and displaying it on the carrier board animation includes:

[0065] The external device is an automatic loading device, which is connected to the magnetron sputtering coating device through EIP communication, and is used to automatically complete the carrier loading process and generate carrier information in real time;

[0066] The carrier information transmitted by the automatic loading device is received and displayed on the carrier animation. Optionally, the carrier information includes the carrier ID and whether there is a silicon wafer on the carrier.

[0067] The process principle of magnetron sputtering coating equipment is to rely on a DC power supply to ionize argon atoms in argon gas into argon ions under vacuum conditions. The argon ions bombard the cathode target made of indium tin oxide, and the target is sputtered and deposited on the surface of the silicon wafer to form a thin film. During the continuous operation of the power supply, the argon gas and the cathode target are also continuously consumed. However, in the actual production environment, it cannot be guaranteed that there will always be incoming materials and battery silicon wafers for production. In many cases, if there is no incoming material and the staff fails to turn off the power supply in time, a large amount of electricity and cathode target waste will be generated. This phenomenon is common in the industry. In order to solve this problem, in some embodiments, the method also includes:

[0068] Check the carrier information of all carriers in the magnetron sputtering coating equipment in real time. If the animation of a carrier is in the display state, and the carrier information shows that there is no silicon wafer on the carrier, the carrier is determined to be an empty carrier. If all carriers are empty, the equipment is in a no-material state, and the no-material state time is accumulated;

[0069] When the time of the material-free state reaches the set value, the DC power output is reduced and the use and emission of process gases are reduced. When the carrier information is detected to show that there are silicon wafers on the carrier and they enter the chamber, the DC power output and the use and emission of process gases are restored to the initial values.

[0070] By using the above method, when the time of the material-free state reaches the set value, the power output of the DC power supply is reduced, and the use and emission of process gas are reduced, the energy-saving function of waiting for material is realized, and the use cost and energy loss of the equipment are greatly reduced.

[0071] It should be understood by those skilled in the art that the discussion of any of the above embodiments is merely illustrative and is not intended to imply that the scope of the present invention (including the claims) is limited to these examples. Within the scope of the present invention, the technical features in the above embodiments or in different embodiments may be combined, the steps may be implemented in any order, and there are many other variations of the above aspects of the present invention, which are not provided in detail for the sake of simplicity.

[0072] The present invention is intended to cover all such substitutions, modifications and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A control method for magnetron sputtering coating equipment, characterized in that: The following steps are involved: The cavity entry sensor is used to detect in real time whether a carrier board has entered the cavity; When it is detected that a carrier plate enters the chamber, the rotation position of the motor shaft driving the carrier plate is recorded, and the number of revolutions of the rotation position is recorded as 0; When it is detected that the number of revolutions of the motor continues to work reaches a predetermined number, the speed of the motor is controlled to decrease, so that the carrier plate performs a deceleration movement, thereby reducing the movement speed of the carrier plate; Detecting the carrier whose moving speed is reduced by a stop sensor, and when the carrier whose moving speed is reduced is detected, controlling the carrier to stop moving; The predetermined number of turns is obtained by the following steps: Obtain the maximum deceleration a to ensure that the silicon wafer in the carrier does not deviate; The deceleration stop time t1 is obtained by calculating the formula 1 S=-0.5at1 2 (one) Where S is the deceleration stop distance, which represents the distance between the stop sensor and the next-stage chamber gate valve; The speed v of the carrier after the speed is reduced is calculated by formula 2 v=at1 (2) Get the uniform speed V of the carrier and calculate the deceleration time t2 using formula 3 V - v = at2 (three) The distance L1 that the carrier moves when the speed decelerates from V to v is calculated by formula 4. L1=Vt2+(at2 2 ) / 2 (Four) Subtract the distance L1 from the distance between the cavity entry sensor and the stop sensor to obtain the distance L2 from when the carrier is detected by the cavity entry sensor to when it starts to decelerate. Based on the distance L2, the predetermined number of revolutions of the motor is calculated.

2. The control method of a magnetron sputtering coating device according to claim 1, characterized in that: The method further comprises: Set the left margin of the carrier animation in the upper computer display bar, and use the left margin as the starting position of the carrier animation; The cavity entry sensor is used to detect in real time whether a carrier board has entered the cavity. When it is detected that a carrier board has entered the cavity, the carrier board animation of the carrier board is displayed at the starting position of the display bar of the host computer; The encoder is used to obtain the real-time position of the motor. The Trigger function is used to record the position of the motor when the cavity sensor senses the carrier. This position is called the cavity start position. When the carrier continues to move, the real-time position is subtracted from the cavity start position, and then converted into the moving distance of the animation according to a predetermined ratio. This can realize the animation following function, which allows the carrier animation to reflect the actual position of the carrier in the chamber. At the same time, the carrier information received from the external device is displayed on the carrier animation. When the cavity entry sensor detects that the carrier moves into the next cavity, the carrier animation in the previous cavity is set to invisible, the carrier animation in the next cavity is set to visible, and the carrier information is transmitted to the carrier animation in the next cavity for display.

3. The control method of a magnetron sputtering coating device according to claim 2, characterized in that: The receiving of the carrier board information transmitted by the external device and displaying it on the carrier board animation comprises: The external device is an automatic loading device, which is connected to the magnetron sputtering coating device through EIP communication, and is used to automatically complete the carrier loading process and generate carrier information in real time; Receive the carrier information transmitted by the automatic loading equipment and display it on the carrier animation.

4. The control method of a magnetron sputtering coating device according to claim 2, characterized in that: The carrier information includes the carrier ID and whether the carrier has a silicon wafer.

5. The control method of a magnetron sputtering coating device according to claim 1, characterized in that: The method further comprises: Check the carrier information of all carriers in the magnetron sputtering coating equipment in real time. If the animation of a carrier is in the display state, and the carrier information shows that there is no silicon wafer on the carrier, the carrier is determined to be an empty carrier. If all carriers are empty, the equipment is in a no-material state, and the no-material state time is accumulated; When the time of the material-free state reaches the set value, the DC power output is reduced and the use and emission of process gases are reduced. When the carrier information is detected to show that there are silicon wafers on the carrier and they enter the chamber, the DC power output and the use and emission of process gases are restored to the initial values.

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