High-precision reciprocating rotation semiconductor device

Abstract

The utility model provides high-precision reciprocating rotation semiconductor equipment. The high-precision reciprocating rotation semiconductor equipment comprises a carrying platform for carrying a wafer and a driving module, the driving module comprises an upper computer, a single chip microcomputer, a stepping motor, a driver for driving the stepping motor to rotate, an encoder for detecting the position of a rotor of the stepping motor in real time, and a detection device for detecting whether the rotor of the stepping motor is reset or not after the equipment is powered off; the encoder is arranged on a rotor of the stepping motor, and the driver is electrically connected with the stepping motor; the single-chip microcomputer is connected with the upper computer, the encoder and the driver, and the detection device is installed on a stator of the stepping motor. By adopting the semiconductor equipment provided by the invention, the process uniformity can be remarkably improved, the working efficiency of operators can be greatly improved, the labor intensity of the operators can be reduced, the use cost of the equipment can be reduced, and the output rate of the equipment can be improved.

Description

Technical Field

[0001] This utility model relates to the field of integrated circuit manufacturing equipment, and in particular to a high-precision reciprocating rotating semiconductor device. Background Technology

[0002] In semiconductor chip manufacturing, wafers are typically rotated to improve process uniformity. For example, in chemical vapor deposition and physical vapor deposition equipment, during the wafer coating deposition process, radio frequency (RF) is activated while the rotating component (Rotor) rotates repeatedly from 0 degrees to 360 degrees to improve the uniformity of wafer coating.

[0003] The rotation of the rotor in existing reciprocating rotary CVD equipment is controlled by a host computer program, which drives a servo motor to perform reciprocating rotation. Due to the limitations of existing equipment, its operation still heavily relies on manual labor. Specifically, the general operating procedure of existing reciprocating rotary equipment includes: (1) The operator calculates the required rotation speed V based on the RF start time T, the number of rotations X, and the previously accumulated process data; (2) The operator sets the number of rotations X, the rotation speed V, and the rotation angle θ on the host computer program interface; (3) The rotary driver controls the servo motor to perform periodic reciprocating rotation. This process is not only time-consuming, resulting in low work efficiency and equipment output, but also prone to process defects due to calculation errors.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this utility model and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this utility model. Utility Model Content

[0005] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a high-precision reciprocating rotary semiconductor device to solve the problems of existing reciprocating rotary CVD equipment and other semiconductor equipment requiring operators to manually calculate and set parameters such as the number of rotations and rotation speed of the rotating parts, resulting in low work efficiency and equipment output, and easy to cause process defects due to calculation errors.

[0006] To achieve the above and other related objectives, this utility model provides a high-precision reciprocating rotating semiconductor device. The semiconductor device includes a stage for supporting wafers and a drive module for driving the stage to rotate. The drive module includes a host computer, a microcontroller, a stepper motor, a driver for driving the stepper motor to rotate, an encoder for real-time detection of the rotor position of the stepper motor, and a detection device for detecting whether the rotor of the stepper motor has reset after the device is powered off. The encoder is mounted on the rotor of the stepper motor, and the driver is electrically connected to the stepper motor. The microcontroller is connected to the host computer, the encoder, and the driver, and the detection device is mounted on the stator of the stepper motor.

[0007] Optionally, the microcontroller includes an STM32F103 microcontroller.

[0008] Optionally, the detection device is mounted on the stator of the stepper motor.

[0009] Optionally, the detection device includes a photoelectric switch electrically connected to an encoder to send a signal to the encoder when the rotor of the stepper motor is detected to have returned to the origin position.

[0010] Optionally, the host computer and the microcontroller are connected via serial communication.

[0011] Optionally, the semiconductor device includes one of a chemical vapor deposition device and a physical vapor deposition device.

[0012] Optionally, the semiconductor device further includes a tilt sensor for detecting the levelness of the platform, the tilt sensor being electrically connected to a microcontroller or a host computer.

[0013] Optionally, the semiconductor device includes an alarm, which is located outside the semiconductor device and electrically connected to a host computer. When the detection result of the tilt sensor is abnormal, the host computer controls the alarm to issue an alarm message.

[0014] Optionally, the semiconductor device further includes a counter disposed on the stator of the stepper electronics for counting the number of rotor rotations.

[0015] Optionally, the encoder includes a photoelectric encoder.

[0016] As described above, the high-precision reciprocating rotary semiconductor device provided by this utility model has the following beneficial effects: The high-precision reciprocating rotary semiconductor device uses an encoder to detect the position of the stepper motor rotor in real time, controlling the response time of each cycle to within 1 millisecond. Furthermore, a detection device checks whether the rotor has reset after each power outage, ensuring that the initial position of the rotor remains consistent during each operation. This allows for high-speed and precise control of the stepper motor to rotate according to a set time and number of revolutions. The entire process eliminates the need for operators to manually calculate the rotation speed, saving operating time, improving work efficiency, and reducing human error. Using the semiconductor device provided in this application can significantly improve process uniformity, such as improving the uniformity of wafer coating, and can greatly improve the work efficiency of operators, reduce their labor intensity, help reduce equipment operating costs, and increase equipment output. Attached Figure Description

[0017] Figure 1 The diagram shown is a structural schematic of a high-precision reciprocating rotating semiconductor device provided by this utility model. Detailed Implementation

[0018] The following specific examples illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification. This utility model can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of this utility model. For ease of explanation, when detailing the embodiments of this utility model, the cross-sectional views showing the device structure may be partially enlarged without adhering to the general scale, and the schematic diagrams are merely examples and should not limit the scope of protection of this utility model. Furthermore, in actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0019] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0020] In the context of this invention, the described structure of the first feature "above" the second feature may include embodiments in which the first and second features are formed in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0021] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of this utility model. Therefore, the drawings only show components related to this utility model and are not drawn according to the actual number, shape, and size of the components in the actual implementation. In the actual implementation, the form, quantity, and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex. To keep the illustrations as concise as possible, not all structures are indicated in the drawings.

[0022] Existing reciprocating rotary semiconductor equipment requires operators to calculate the rotation speed and number of revolutions of rotating components (such as motors) according to each recipe, which increases the labor intensity of operators, reduces work efficiency, and is also prone to process defects due to operational errors.

[0023] Furthermore, through repeated experimental testing and analysis, it was found that in existing coating deposition equipment, when the host computer program controls the rotary driver, there is a communication time delay of approximately 200 milliseconds per revolution of the servo motor due to the DeviceNet communication time between the host computer and the driver. If 10 revolutions are required, the cumulative communication delay will be 2000 milliseconds. Regardless of the communication method used between the host computer and the driver, such as industrial communication methods like CC-Link or PROFIBUS, this communication delay cannot be avoided. This time delay prevents the servo motor from achieving the expected rotational accuracy, further resulting in the actual rotation of the servo motor failing to meet the rotation number X and RF activation time T set in the coating process during the RF activation period. In view of this, the inventors of this case, after extensive research, proposed an improvement solution.

[0024] like Figure 1 As shown, this utility model provides a high-precision reciprocating rotating semiconductor device. The semiconductor device includes a host computer 14, a stage 11 for carrying wafers, and a drive module for driving the stage 11 to rotate.

[0025] The semiconductor device typically also includes a cavity 12 for performing semiconductor processing. The cavity 12 is, for example, a generally cylindrical metal cavity. Gate valves 121 for wafer entry and exit may be provided on the sidewalls of the cavity 12. An exhaust port 122 connected to a vacuum pump may be provided in the lower middle part of the cavity 12, such as the bottom of the cavity 12, to control the vacuum level inside the cavity 12 and to promptly release excess gas inside the cavity 12. The semiconductor device can be any device that needs to drive wafer rotation during the processing to improve process uniformity. The semiconductor device can be any of a physical vapor deposition (PVD) device, a chemical vapor deposition (CVD) device, and a dry etching device. In particular, PVD and CVD devices have very high requirements for process uniformity, and are therefore especially suitable for the solutions described in this application. For example, in some examples, the semiconductor device is a CVD device, and therefore a spray head for supplying a reaction source into the cavity 12 may be provided at the top of the cavity 12, and an radio frequency power supply electrically connected to the spray head may also be included. If it is a physical vapor deposition (PVD) apparatus, a sputtering assembly such as a target and a magnetron can be installed on the top of the cavity 12. In the case of a chemical vapor deposition (CVD) or physical vapor deposition (PVD) apparatus, a baffle (not shown) or other components to prevent contamination of the cavity 12 can be installed on the inner wall surface of the cavity 12.

[0026] The stage 11 is located inside the cavity 12, and a support shaft 13 may be provided at its bottom, extending downwards to the outside of the cavity 12. The stage 11 can be an electrostatic chuck, fixing the wafer based on the principle of electrostatic adsorption. A vacuum adsorption port may also be provided on the stage 11, fixing the wafer by negative pressure adsorption. Heating and / or cooling pipes may also be provided inside the stage 11 to adjust the wafer temperature according to process requirements. Components such as edge rings may also be provided above the circumferential edge of the stage 11 to control and adjust the diffusion direction of the process airflow, thereby limiting wafer edge deposition or etching. The stage 11 is directly or indirectly connected to a stepper motor 16. When the stage 11 rotates periodically under the drive of the stepper motor 16, it drives the wafer on its surface to rotate synchronously and periodically.

[0027] The drive module is typically located outside the cavity and includes a microcontroller 15, a stepper motor 16, a driver 17 that drives the stepper motor 16 to rotate, an encoder 18 for real-time detection of the rotor position of the stepper motor 16, and a detection device for detecting whether the rotor of the stepper motor 16 has reset after the device is powered off, for example, detecting whether the rotor has returned to the origin position after the power is off. The detection device is, for example, mounted on the stator of the stepper motor.

[0028] A stepper motor 16, also known as a pulse motor, is a type of electric motor that converts electrical pulse signals into corresponding angular or linear displacement. In this embodiment, the stepper motor 16 is preferably a high-precision permanent magnet stepper motor 16 or a hybrid stepper motor 16. The stepper motor 16 includes a stationary stator and a rotatable rotor. The rotor is, for example, disposed inside the stator. The rotor of the stepper motor can be connected to the platform 11 via a connecting assembly such as a lead screw. For example, the motor is disposed outside the cavity 12 and on one side of the support shaft 13, and is connected to the support shaft 13 via a connecting assembly such as a lead screw or flange, so that the rotation of the rotor drives the platform 11 to rotate. In some other examples, the support shaft 13 can also be placed on a rotating platform, and the rotor drives the rotating platform to rotate, thereby driving the platform 11 to rotate. In other examples, the platform 11 can also be rotated by magnetic coupling rotation, and there are no specific limitations.

[0029] The driver 17 directly drives the rotation of the stepper motor 17. It is preferably a high-precision driver such as a linear driver, and preferably a driver with closed-loop control.

[0030] The encoder 18 is a device that encodes and converts signals (such as bitstreams) or data into a signal form that can be used for communication, transmission, and storage. In this embodiment, the encoder 18 is mounted on the rotor of the stepper motor 16, for example, by means of screws or other connecting parts, to detect the position information of the rotor of the stepper motor 16 in real time, including rotation angle and number of rotations, and convert the acquired information into electrical signals. The driver 17, which is electrically connected to the stepper motor 16, is an actuator that converts electrical pulses into angular displacement, and consists of a pulse generation control unit, a power drive unit, a protection unit, etc. The microcontroller 15 is connected to the host computer 14, the encoder 18, and the driver 17. A single-chip microcomputer (MCU) is an integrated circuit chip that uses very large-scale integrated circuit (VLSI) technology to integrate a central processing unit (CPU) with data processing capabilities, random access memory (RAM), read-only memory (ROM), various I / O ports and interrupt systems, timers / counters, and other functions (and possibly display driver circuits, pulse width modulation circuits, analog multiplexers, A / D converters, etc.) onto a single silicon chip, forming a small but complete microcomputer system. MCUs are widely used in industrial control. Existing high-end MCUs on the market come with built-in programs; therefore, the appropriate MCU model can be selected based on the required expansion interfaces. In this embodiment, the MCU 15, through communication connections with the host computer 14, encoder 18, and driver 18, can receive information from the host computer 14 and encoder 18, and control the driver 17 to drive the stepper motor 16 to periodically reciprocate, thereby driving the stage and the wafer located on the stage to periodically reciprocate. Therefore, the selected MCU must at least include ports that can connect to the host computer, encoder, and driver. In another example, the microcontroller can send the information received from the encoder to the host computer, which then controls the operation of the driver.

[0031] The exemplary working principle of the high-precision reciprocating rotary semiconductor device provided in this embodiment is as follows: The host computer 14 transmits the process parameters RF on-time T, number of rotations X, and rotation angle θ to the microcontroller 15 via a communication connection. The microcontroller 15 calculates the required speed and acceleration of the stepper motor 16 and sends PWM pulses to the motor driver 17, causing the stepper motor 16 to drive the rotor to rotate in the forward direction according to the rotation angle θ specified in the process parameters. Simultaneously, the encoder 18 mounted on the rotor transmits the actual rotor position to the microcontroller 15 in real time. When the rotor actually reaches the required angle θ, the microcontroller 15 sends PWM pulses to cause the stepper motor 16 to rotate in the reverse direction to reach the origin position. In this way, the rotor can periodically reciprocate according to the number of rotations T specified in the process parameters. After each power outage, the host computer 14 or the encoder 18 controls the rotor to reset, for example, return to the origin position, based on information detected by the detection device, ensuring that the rotor's initial position is the same for each operation and improving the device's working accuracy. Figure 1 The arrows in the diagram roughly indicate the direction of signal transmission between the various units of the drive module, but are not strictly limited.

[0032] To verify the effectiveness of this application, the inventors conducted a comparative experiment using a CVD coating equipment.

[0033] (1) The existing technical solution was used for testing. The upper computer program was used to control the rotor rotation. The rotor was to rotate 6 times in 30 seconds, with each rotation being 360 degrees. Due to communication delay and other reasons, the actual operation of the operator was that the rotor needed to rotate for 31.2 seconds to complete 6 rotations, with each rotation being 360 degrees. This means that within 30 seconds, the rotor still had 83 degrees (360x60÷31.2x1.2) left to rotate.

[0034] (2) The rotor rotation is controlled by the drive module proposed in this application, which includes a driver 17, a stepper motor 16, an encoder 18, and a detection device. The rotor rotates 6 times in 30 seconds, with each rotation being 360 degrees. Due to the optimized structure of the drive module, the communication latency is significantly reduced. For example, with the STM32F103 microcontroller 15 and other configurations, the actual operation shows that the rotor only needs to rotate 6 times in 30.006 seconds, with each rotation being 360 degrees. This means that within 30 seconds, the rotor still has 0.4 degrees (360x60÷30.006x0.006) left to rotate, which greatly improves the uniformity of wafer coating.

[0035] This invention provides a high-precision reciprocating rotary semiconductor device that uses an encoder to detect the position of a stepper motor rotor in real time. The response time for each cycle can be controlled to within 1 millisecond. Furthermore, a detection device checks whether the rotor has reset after each power outage, ensuring that the initial position of the rotor remains consistent during each operation. This allows for high-speed and precise control of the stepper motor to rotate according to a set time and number of revolutions. The entire process eliminates the need for manual calculation of rotation speed by the operator, saving operating time, improving work efficiency, and reducing human error. Using the semiconductor device provided in this application can significantly improve process uniformity, such as improving the uniformity of wafer coating, and can greatly improve the work efficiency of operators, reduce their labor intensity, help reduce equipment operating costs, and increase equipment output.

[0036] In this embodiment, encoder 18 is preferably a photoelectric encoder, which has the advantages of high precision, high resolution and high reliability, and helps to improve the accuracy of the equipment.

[0037] In this embodiment, the microcontroller 15 is preferably a high-performance general-purpose model such as a 16-bit or 32-bit microcontroller, which not only facilitates connection with various components but also has advantages such as high-speed computing. In one example, the microcontroller 15 adopts an STM32F103 microcontroller, which has advantages such as high performance, low power consumption, rich peripheral interfaces, and ease of development. It is suitable for communication interconnection between the device and other devices in the factory and has wide applications in semiconductor equipment control.

[0038] The host computer 14 is, for example, a PC, which is preferably connected to the microcontroller 15 via serial communication to ensure stable and efficient data transmission between the two and to help reduce communication latency. The host computer 14 and the microcontroller 15 can be located in the same physical space, for example, both in a cleanroom near the cavity 12. Alternatively, they can be located in different physical spaces; for example, the microcontroller 15 can be located in a cleanroom near the cavity 12, while the host computer 14 can be located in an office or control room outside the cleanroom. In a preferred example, the host computer 14 and the microcontroller 15 are both located in the cleanroom, and the host computer 14 is communicatively connected to a PC outside the cleanroom to synchronize data with the PC in real time. Furthermore, in a preferred example, the operation of other mechanisms of the equipment is also controlled by the host computer; for example, the operation of the gas supply device and the heating device is controlled by the host computer according to a pre-stored menu.

[0039] In some examples, the detection device is mounted on the stator of the stepper motor 16. For example, in some examples, the detection device includes a photoelectric switch 19, fixedly mounted on the stator, such as at the rotor origin position. When the device is powered off and the rotor rotates back to the origin position, the photoelectric switch 19 emits a light signal; conversely, if the rotor does not return to the origin, the photoelectric switch 19 is not activated. In a further example, the photoelectric switch 19 is electrically connected to the encoder 18 to send a signal to the encoder 18 when the rotor of the stepper motor 16 is detected to have returned to the origin position. If the rotor does not reset, the encoder 18 controls the driver 17 to drive the rotor to rotate and reset before the process begins. Alternatively, the photoelectric switch 19 can also be electrically connected to the host computer 14, which can directly drive the rotor to reset, or the host computer 14 can control the encoder 18 to drive the rotor to reset; there are no strict limitations on this. In other examples, the detection device can also be other types of sensors, which, depending on the type, can be mounted on the housing of the stepper motor 16 or in other locations. For example, the detection device can also use a sensor including a transmitter and a receiver, which are mounted on the rotor and stator respectively. When the rotor returns to its original position, the sensor sends a reset signal. In other examples, a reset mark can be set on the stator. The detection device only sends a reset signal to the encoder 18 / host computer 14 when the rotor returns to the position of the corresponding reset mark. In comparison, mounting the detection device on the stator is easier to install and helps improve the stability of the detection device.

[0040] In some examples, the semiconductor device further includes a tilt sensor 20 for detecting the levelness of the stage 11, which is electrically connected to the microcontroller 15 or the host computer 14. Alternatively, the tilt sensor 20 can be directly connected to the host computer 14, or connected to the host computer 14 via the microcontroller 15. The tilt sensor 20 is, for example, disposed on the lower surface of the stage 11. When the stage 11 is detected to be out of level, the microcontroller or the host computer 14 controls the stepper motor 16 to stop rotating, preventing the wafer on the stage 11 from falling during rotation. Preferably, the host computer 14 can control the stepper motor 16 to gradually decelerate until the speed drops to zero, preventing damage to the wafer and other process components within the cavity 12 from sudden equipment stoppage. In other examples, other sensors or other methods can be used to detect the levelness of the stage 11; this is not strictly limited.

[0041] In some examples, the semiconductor device also includes an alarm 21, which is located externally to the semiconductor device and electrically connected to the host computer 14. For example, in some examples, the alarm 21 is an audible and visual alarm 21, which is fixed to the top or side wall of the cavity 12. When the device malfunctions, for example, when the tilt sensor 20 detects that the platform 11 is not level, the alarm 21 issues an alarm message to remind the staff to find the cause of the malfunction as soon as possible. The host computer 14 can perform an emergency stop on the device based on the alarm message.

[0042] In some examples, the semiconductor device also includes a counter (not shown) mounted on the stator of the stepper motor for counting the number of rotor revolutions. This counter can be used as a backup and verification mechanism for the encoder mounted on the rotor. The counter can be the same instrument as the encoder mounted on the rotor, such as a photoelectric encoder, a magnetic encoder, or other components capable of counting the revolutions of a rotating object, including multi-turn counters, torsion ring counters, etc. A host computer can connect the encoder, counter, and alarm to issue an alarm when there is a discrepancy between the number of revolutions counted by the encoder and the counter, and the host computer can control the stepper motor to decelerate or stop rotating.

[0043] The high-precision reciprocating rotating semiconductor device provided in this embodiment can be used in processes such as thin film deposition and dry etching, which require extremely high process uniformity. Depending on the specific application, other aspects of the device's structure may vary, and will not be elaborated upon here.

[0044] In summary, the high-precision reciprocating rotary semiconductor device provided by this utility model uses an encoder to detect the position of the stepper motor rotor in real time, controlling the response time of each cycle to within 1 millisecond. Furthermore, a detection device checks whether the rotor has reset after each power outage, ensuring that the initial position of the rotor remains consistent during each operation. This allows for high-speed and precise control of the stepper motor to rotate according to a set time and number of revolutions. The entire process eliminates the need for manual calculation of rotation speed by operators, saving operating time, improving work efficiency, and reducing human error. Using the semiconductor device provided in this application can significantly improve process uniformity, such as improving the uniformity of wafer coating, and can greatly improve operator efficiency, reduce their labor intensity, help reduce equipment operating costs, and increase equipment output. Therefore, this utility model effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0045] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.

Claims

1. A high-precision reciprocating rotary semiconductor device, characterized in that, The semiconductor equipment comprises a carrier wafer carrier and a driving module; the driving module comprises a host computer, a single-chip microcomputer, a stepping motor, a driver for driving the stepping motor to rotate, an encoder for detecting the rotor position of the stepping motor in real time, and a detection device for detecting whether the rotor of the stepping motor is reset after the equipment is powered off; the encoder is arranged on the rotor of the stepping motor, and the driver is electrically connected with the stepping motor; the single-chip microcomputer is connected with the host computer, the encoder and the driver, and the detection device is installed on the stator of the stepping motor.

2. The semiconductor device according to claim 1, wherein The single-chip microcomputer comprises an STM32F103 single-chip microcomputer.

3. The semiconductor device of claim 1, wherein The detection device is arranged on the stator of the stepping motor.

4. The semiconductor device according to claim 1, wherein The detection device comprises a photoelectric switch, which is electrically connected with the encoder to send a signal to the encoder when the rotor of the stepping motor returns to the original position.

5. The semiconductor device of claim 1, wherein: The host computer and the single-chip microcomputer are connected through a serial port communication.

6. The semiconductor device according to claim 1, wherein The semiconductor equipment comprises one of a chemical vapor deposition equipment and a physical vapor deposition equipment.

7. The semiconductor device according to claim 1, wherein The semiconductor equipment further comprises an inclination sensor for detecting the levelness of the carrier, which is electrically connected with the single-chip microcomputer or the host computer.

8. The semiconductor device according to claim 7, wherein The semiconductor equipment comprises an alarm, which is arranged outside the semiconductor equipment and is electrically connected with the host computer; when the detection result of the inclination sensor is abnormal, the host computer controls the alarm to send an alarm information.

9. The semiconductor device according to claim 1, wherein The semiconductor equipment further comprises a counter arranged on the stator of the stepping motor, which is used for counting the number of rotations of the rotor.

10. The semiconductor device according to any one of claims 1 to 9, wherein: The encoder comprises an optical encoder.

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