Wafer coating device and ALD equipment

Abstract

The invention provides a wafer coating device and ALD equipment, and relates to the field of semiconductor manufacturing. In the invention, because the film coating module can form the magnetic field in the process of driving the wafer to rotate, the calibration module can adjust the wafer position of the wafer on the wafer bearing surface of the film coating module based on the plurality of first magnetic field intensity measurement values obtained by measuring the magnetic field by the measurement module, and adjust the notch orientation of the wafer; and when the position of the wafer is adjusted to the central position of the wafer bearing surface and the orientation of the notch is adjusted to the preset orientation, ALD coating is carried out on the wafer through the coating module. Therefore, the correction of the wafer position and the adjustment of the wafer direction can be realized without additionally adding a calibration module comprising a visual sensor in the wafer transmission process, the wafer transmission process is simplified, and the wafer transmission efficiency is improved.

Description

Technical Field

[0001] The present invention relates to the field of semiconductor manufacturing, and particularly to a wafer coating device and an ALD device. Background Art

[0002] In an atomic layer deposition (ALD) device, the gas flow in the cavity will flow along a planned path. Therefore, the placement direction and position of the wafer in the ALD device have a great influence on the coating effect.

[0003] Refer to Figure 1 As shown, during the process of coating the wafer in the ALD device, the wafer is sent into the vacuum transfer module (VTM) in the ALD device through a standard mechanical interface (SMIF) module. After the wafer is transferred from the atmospheric environment to the vacuum environment, the wafer can be calibrated through a calibration module (i.e., the Aligner module) to correct the position of the wafer and adjust the direction of the wafer (for example, the notch of the wafer faces uniformly). Then, the calibrated wafer is sent into the reaction chamber (RC) of the process module (PM) through the transfer module (TM) for the ALD coating process. Further, after the wafer coating is completed, the coated wafer is taken out of the RC through the TM and sent into the cooler Cooler for cooling. Finally, the coated wafer is transferred from the vacuum environment to the atmospheric environment through the VTM and taken out by the SMIF module.

[0004] Using the above wafer calibration method, since the vision sensor for realizing wafer calibration is large in volume and not resistant to high temperature, the vision sensor cannot be placed inside the RC. Moreover, the method of adding a calibration module including a vision sensor during the wafer transfer process increases the volume of the ALD device, makes the wafer transfer process cumbersome, and affects the efficiency of wafer transfer. Summary of the Invention

[0005] Embodiments of the present invention provide a wafer coating device and an ALD device to solve the problems that the ALD device is large in volume and the wafer transfer efficiency is affected due to adding a calibration module including a vision sensor during the wafer transfer process.

[0006] In a first aspect, embodiments of the present invention provide a wafer coating device, which includes: a measurement module, a calibration module, and a coating module, wherein,

[0007] The measurement module is configured to measure the magnetic field intensity of the magnetic field formed during the process of the coating module driving the wafer to rotate, and obtain a plurality of first magnetic field intensity measurement values;

[0008] The calibration module is configured to adjust the wafer position of the wafer on the wafer bearing surface of the coating module and adjust the notch orientation of the wafer based on the plurality of first magnetic field intensity measurement values; wherein, the wafer position represents the central position of the wafer;

[0009] The coating module is configured to perform ALD coating on the wafer when the wafer position is adjusted to the central position of the wafer bearing surface and the notch orientation is adjusted to a preset orientation.

[0010] In an alternative embodiment, the measurement module includes a plurality of measurement units, and the plurality of measurement units are evenly distributed around the central position of the wafer bearing surface, and each measurement unit is configured to measure the magnetic field intensity of the magnetic field formed during the process of the coating module driving the wafer to rotate.

[0011] In an alternative embodiment, the measurement unit is a tunnel magnetoresistance (TMR) sensor.

[0012] In an alternative embodiment, the calibration module includes:

[0013] A first calibration unit configured to determine the rotation angles of the coating module when the maximum magnetic field intensity measurement value and the target magnetic field intensity measurement value with a magnetic field intensity of a preset magnetic field intensity are measured based on the first measurement time of the maximum magnetic field intensity measurement value included in the plurality of first magnetic field intensity measurement values and the second measurement time of the target magnetic field intensity measurement value;

[0014] And, based on the distance between the central position of the wafer obtained based on the rotation angle and the central position of the wafer bearing surface, adjust the wafer from the wafer position to the central position of the wafer bearing surface; wherein, the preset magnetic field intensity is the magnetic field intensity of the magnetic field formed during the process of the coating module driving the wafer to rotate when the central position of the wafer overlaps with the central position of the wafer bearing surface;

[0015] A second calibration unit configured to, when determining that the wafer position is the central position of the wafer bearing surface, instruct the coating module to drive the wafer to rotate, and when the magnetic field intensity difference between two adjacent second magnetic field intensity measurement values is greater than a set difference threshold, determine that the coating module has adjusted the notch orientation of the wafer to the preset orientation, and instruct the coating module to stop rotating the wafer.

[0016] In an alternative embodiment, the first calibration unit is further configured to determine that the center position of the wafer overlaps with the center position of the wafer carrier surface when all of the plurality of first magnetic field strength measurement values belong to the magnetic field strength interval associated with the target magnetic field strength measurement value.

[0017] In an alternative embodiment, the first calibration unit includes:

[0018] A first processing subunit, configured to determine the rotation angle based on the rotation angular velocity of the coating module and the time difference between the second measurement time and the first measurement time;

[0019] And, based on the rotation angle and the distance from the measurement position corresponding to the target magnetic field strength measurement value in the wafer carrier surface to the line connecting the center position of the wafer and the center position of the wafer carrier surface, determine the spacing;

[0020] A position adjustment subunit, configured to adjust the wafer from the wafer position to the center position of the wafer carrier surface based on the spacing and along the line connecting the center position of the wafer and the center position of the wafer carrier surface.

[0021] In an alternative implementation manner, the second calibration module includes:

[0022] A second processing subunit, configured to generate a first indication message when determining that the wafer position is the center position of the wafer carrier surface, and generate a second indication message when the magnetic field strength difference between the two second magnetic field strength measurement values is greater than the set difference threshold; wherein, the first indication message is used to instruct the coating module to drive the wafer to rotate, and the second indication message is used to instruct the coating module to stop rotating the wafer;

[0023] A message sending subunit, configured to send the first indication information or the second indication message to the coating module.

[0024] In an alternative implementation manner, the coating module includes:

[0025] An electrostatic adsorption unit, configured to carry the wafer and form the magnetic field during the rotation of the wafer;

[0026] A rotary coating unit, configured to drive the wafer to rotate.

[0027] In an alternative implementation manner, the coating module further includes:

[0028] An energy supply unit, configured to supply power to the electrostatic adsorption unit so that the electrostatic adsorption unit forms the magnetic field during the rotation of the wafer driven by the rotary coating unit.

[0029] In a second aspect, an ALD device provided by an embodiment of the present invention further includes a wafer coating device as described in the first aspect above provided by the embodiment of the present invention.

[0030] The beneficial effects of the present invention are as follows:

[0031] In the wafer calibration device provided by the embodiment of the present invention, since a magnetic field will be formed during the process of the coating module driving the wafer to rotate, the calibration module can adjust the wafer position of the wafer on the wafer bearing surface of the coating module and adjust the notch orientation of the wafer based on a plurality of first magnetic field intensity measurement values obtained by the measurement module measuring the magnetic field. Furthermore, when the wafer position is adjusted to the center position of the wafer bearing surface and the notch orientation is adjusted to a preset orientation by the coating module, ALD coating is performed on the wafer. Thus, it can be seen that without additionally adding a calibration module including a vision sensor during the wafer transfer process, the correction of the wafer position and the adjustment of the wafer direction can be achieved, simplifying the wafer transfer process and improving the wafer transfer efficiency.

[0032] In addition, other features and advantages of the present invention will be described in the subsequent specification, and, in part, will be obvious from the specification, or will be understood by implementing the present invention. The objectives and other advantages of the present invention can be achieved and obtained by the structures specifically pointed out in the written specification, claims, and drawings. Description of the Drawings

[0033] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiment descriptions. Obviously, the drawings described here are used to provide a further understanding of the present invention, constitute a part of the present invention, and do not constitute an improper limitation to the present invention. In the drawings:

[0034] Figure 1 It is a logical schematic diagram of a related ALD coating provided by an embodiment of the present invention;

[0035] Figure 2 It is an application scenario schematic diagram of a related calibration module provided by an embodiment of the present invention;

[0036] Figure 3 It is a notch schematic diagram of a wafer provided by an embodiment of the present invention;

[0037] Figure 4 It is a composition structure schematic diagram of a wafer coating device provided by an embodiment of the present invention;

[0038] Figure 5 It is another composition structure schematic diagram of a wafer coating device provided by an embodiment of the present invention;

[0039] Figure 6Schematic diagram of a wafer in an offset state provided by an embodiment of the present invention;

[0040] Figure 7 Schematic diagram of the composition structure of another wafer coating device provided by an embodiment of the present invention;

[0041] Figure 8 Schematic diagram of a scenario for determining a rotation angle provided by an embodiment of the present invention;

[0042] Figure 9 Schematic diagram of the charge distribution of an electrostatic adsorption unit provided by an embodiment of the present invention;

[0043] Figure 10 Schematic diagram of the electrode arrangement of an electrostatic adsorption unit provided by an embodiment of the present invention;

[0044] Figure 11 Schematic diagram of the change in the electric field strength of a spatial electric field provided by an embodiment of the present invention;

[0045] Figure 12 Front view schematic diagram of the composition structure of a wafer calibration device provided by an embodiment of the present invention.

[0046] Reference numerals: 1 - measurement module; 11 - measurement unit; 1n - measurement unit; 2 - calibration module; 21 - first calibration unit; 211 - first processing subunit; 212 - position adjustment subunit; 22 - second calibration unit; 221 - second processing subunit; 222 - message sending subunit; 3 - coating module; 31 - electrostatic adsorption unit; 32 - rotary coating unit; 33 - power supply unit. Detailed implementation manners

[0047] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although some embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as limited to the embodiments set forth herein. Instead, these embodiments are provided to more thoroughly and completely understand the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not used to limit the protection scope of the present invention. The term "including" and its variations used herein are open-ended, that is, "including but not limited to". The term "based on" is "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence relationship of the functions performed by these devices, modules or units.

[0048] It should be noted that the modification of "one" and "multiple" mentioned in the present invention is illustrative rather than restrictive. Those skilled in the art should understand that, unless otherwise clearly specified in the context, it should be understood as "one or more".

[0049] The names of the messages or information exchanged between multiple devices in the embodiments of the present invention are only for illustrative purposes and are not used to limit the scope of these messages or information.

[0050] First, a brief introduction to the design concept of the embodiments of the present invention is as follows:

[0051] The direction and position of wafer placement have a great impact on the coating effect. Therefore, before coating the wafer through the ALD device, it is necessary to calibrate the direction and position of wafer placement. As Figure 1 shown, usually during the wafer transfer process of the ALD device, a calibration module (i.e., the Aligner module) is added as a separate step during the wafer transfer process.

[0052] Refer to Figure 2 shown, which is a schematic diagram of an application scenario of a related calibration module provided by an embodiment of the present invention. This application scenario includes: a rotating motor M, a rotating working plate, a wafer, a vision sensor, a fixing block for fixing the vision sensor, a Z-Axis motion axis (i.e., the Z-axis) and an X-Axis motion axis (i.e., the X-axis). Among them, the wafer is placed on the rotating working plate, and the vision sensor set in the Aligner module can identify the boundary and position of the current wafer, so as to determine the center position (i.e., the central position) of the wafer. When the center position is offset, the wafer is moved two-dimensionally through the combination of the vision sensor and a position correction module (such as a robotic arm) to correct the position of the wafer until the position calibration is successful.

[0053] After aligning the center of the wafer with the center of the rotating working plate, the rotating motor M drives the rotating working plate to rotate, and the vision sensor will look for the Figure 3 shown notch of the wafer at a specified position. When the vision sensor recognizes that the notch of the wafer reaches the specified position, a signal indicating that the notch direction of the wafer is calibrated to the specified direction can be generated. Further, after determining that the wafer calibration is completed, Figure 1 shown TM can take away the calibrated wafer from the Aligner module.

[0054] In the above-mentioned wafer calibration method, the visual sensor is usually not placed inside the RC of the PM due to its large size and inability to withstand high temperatures. Therefore, a wafer calibration module needs to be added during the wafer transmission process. However, this increases the volume of the wafer transmission equipment (i.e., ALD equipment), and makes the wafer transmission process cumbersome, affecting the efficiency of wafer transmission. Moreover, the visual sensor involves the two-dimensional movement process of the spatial settlement results and the position correction module, and the calculation is relatively complicated. In addition, the following errors are inevitable when using visual sensors for wafer calibration:

[0055] 1. Structural error: It is the error caused directly or indirectly by inaccurate machining and assembly of the calibration device. This type of error can only be reduced by compensation algorithms and improving machining accuracy.

[0056] 2. Motion error: On the one hand, errors will occur when the wafer is sent to the calibration module. At the same time, the calibrated wafer is sent to the TM and then to the PM through the transmission device. Certain motion errors will occur during the transmission process. However, due to the large size and poor heat resistance of the visual sensor, it cannot be placed in the RC of the PM. Therefore, there must be multiple transmission processes to accumulate errors, which will eventually affect the direction accuracy of the wafer during the process, thereby affecting the process accuracy.

[0057] 3. Detection error: The wafer calibration process relies on the decoupling and coordinate transformation calculation of the parameters observed by the visual sensor. On the one hand, due to the structural error of the calibration device, the coordinates observed before decoupling and transformation are not complete circles, but projected ellipses facing a certain direction. On the other hand, the visual sensor has certain observation errors, which in turn affects the calculation accuracy, resulting in errors in the calculation of the center and the boundary, and ultimately affects the wafer calibration accuracy.

[0058] 4. Calculation error: Visual observation and optical methods are easily affected by data points and clusters. There is a lot of noise interference in the optical observation process, which has a great impact on the calculation results. In order to avoid this influence, a certain data preprocessing algorithm is required to screen and sort the sampling points. However, the large amount of sampling point data leads to a large proportion of data preprocessing time in the total algorithm time.

[0059] In view of this, in order to solve or improve the above problems, the embodiment of the present invention provides a wafer coating device to avoid the problems caused by adding a calibration module including a visual sensor during the wafer transmission process. Figure 4 As shown, the wafer coating device includes: a measuring module 1, a calibration module 2 and a coating module 3. Among them, the measuring module 1 is used to measure the wafer (not in Figure 4During the rotation (shown in the figure), the magnetic field intensity of the magnetic field formed is obtained, and a plurality of first magnetic field intensity measurement values are acquired. The calibration module 2 is used to adjust the wafer position of the wafer on the wafer carrier surface of the coating module 3 based on the plurality of first magnetic field intensity measurement values, and to adjust the notch orientation of the wafer. Among them, the aforementioned wafer position represents the (geometric) center position of the wafer (such as the center of the circle). The coating module 3 is used to perform ALD coating on the wafer when the wafer position is adjusted to the center position of the wafer carrier surface and the notch orientation is adjusted to the preset orientation.

[0060] In this wafer coating apparatus, since a magnetic field will be formed when the coating module 3 drives the wafer to rotate, the calibration module 2 can adjust the wafer position of the wafer on the wafer carrier surface of the coating module 3 based on the plurality of first magnetic field intensity measurement values obtained by the measurement module 1 measuring the magnetic field, and adjust the notch orientation of the wafer. Furthermore, when the wafer position is adjusted to the center position of the wafer carrier surface and the notch orientation is adjusted to the preset orientation, the coating module 3 performs ALD coating on the wafer. Thus, it can be seen that there is no need to additionally add a calibration module including a vision sensor during the wafer transfer process, which can achieve the correction of the wafer position and the adjustment of the wafer direction, simplifies the wafer transfer process, and improves the efficiency of wafer transfer.

[0061] To improve the discrimination speed of whether the wafer position of the wafer is at the center position of the wafer carrier surface, in an optional implementation, refer to Figure 5 As shown, the measurement module 1 may include a plurality of measurement units (i.e., measurement units 11 to 1n), and the measurement units 11 to 1n are evenly distributed around the center position of the wafer carrier surface. Among them, each measurement unit can be used to measure the magnetic field intensity of the magnetic field formed during the rotation of the coating module 3 driving the wafer.

[0062] It should be noted that the above-mentioned plurality of measurement units can be arranged in the plane where the wafer carrier surface is located. Of course, they can also be arranged in a plane above the plane where the wafer carrier surface is located. The embodiments of the present invention do not limit this.

[0063] Since the above-mentioned multiple measurement units are evenly distributed around the center position of the wafer carrying surface, that is, the distance from each measurement unit to the center position of the wafer carrying surface is the same. In this way, if the magnetic field intensities measured by the above-mentioned multiple measurement units at the same time are the same or belong to a preset magnetic field intensity range, it can be determined that the wafer position of the wafer overlaps with the center position of the wafer carrying surface, that is, there is no need to correct the position of the wafer. On the contrary, if the magnetic field intensities measured by the above-mentioned multiple measurement units at the same time are different or there are magnetic field intensity measurement values that do not belong to the preset magnetic field intensity range, it can be determined that the wafer position of the wafer is not at the center position of the wafer carrying surface. In other words, when the wafer is placed on the wafer carrying surface, the coating module 3 rotates the wafer at a fixed angular velocity. During the rotation process, if the magnetic field intensity measurement value of a certain measurement unit is different from the magnetic field intensity measurement values of other measurement units or does not belong to the preset magnetic field intensity range, it can be explained that the wafer position has shifted at this time and correction or calibration should be performed. The offset state is referred to Figure 6 as shown.

[0064] Optionally, the measurement unit can be a TMR sensor. By using the TMR sensor to judge the wafer position, that is, using the magnetic field for shape detection, the volume of the sensor used for wafer calibration is reduced, that is, the vision sensor is no longer used to calibrate the wafer. In addition, the TMR sensor uses a Wheatstone bridge to reduce the influence of temperature on the sensor and can withstand the high temperature inside the RC of the PM. It can be seen that the wafer coating module provided by the embodiment of the present invention reduces the volume of the wafer transfer device, combines the reaction chamber with wafer calibration, simplifies the wafer transfer process, and improves the wafer transfer efficiency.

[0065] In addition, by using the TMR sensor to judge the wafer position, the influence of the structural error in the related technology on wafer calibration is weakened, the deviation of the wafer offset, tilt, etc. caused by the structure of the traditional vision sensor is reduced, and the algorithm is also simpler. There is no need to add complex space and position calculations, nor the huge signal acquisition and vision preprocessing processes in the vision algorithm, reducing the computational complexity and improving the computational efficiency.

[0066] In an alternative implementation, still as Figure 5As shown, the calibration module 2 may include a first calibration unit 21 and a second calibration unit 22. Among them, the first calibration unit 21 is used to determine the rotation angle of the coating module 3 when the maximum magnetic field strength measurement value and the target magnetic field strength measurement value are measured, based on the first measurement time of the maximum magnetic field strength measurement value included in the multiple first magnetic field strength measurement values and the second measurement time of the target magnetic field strength measurement value whose magnetic field strength magnitude is the preset magnetic field strength; and, based on the distance between the center position of the wafer obtained from the rotation angle and the center position of the wafer carrier surface, adjust the wafer from the wafer position to the center position of the wafer carrier surface. Among them, the preset magnetic field strength is the magnetic field strength of the magnetic field formed during the rotation of the coating module 3 driving the wafer when the center position of the wafer coincides with the center position of the wafer carrier surface.

[0067] In the above embodiment, the first calibration module 21 can obtain the target magnetic field strength measurement value whose magnetic field strength magnitude is the preset magnetic field strength, and the maximum magnetic field strength measurement value when the wafer is closest to the magnetic field measurement module 1 from the multiple first magnetic field measurement values. And, since the rotation angle of the coating module 3 when the maximum magnetic field strength measurement value and the target magnetic field strength measurement value are measured is related to the distance between the center position of the wafer and the center position of the wafer carrier surface. Therefore, after determining the rotation angle, the distance between the center position of the wafer and the center position of the wafer carrier surface can be quickly obtained, and then the wafer can be adjusted from the wafer position to the center position of the wafer carrier surface based on the distance between the center position of the wafer and the center position of the wafer carrier surface.

[0068] In an alternative implementation, refer to Figure 7 As shown, the first calibration unit 21 may include a first processing subunit 211 and a position adjustment subunit 212. Among them, the first processing subunit 211 is used to determine the rotation angle based on the rotation angular velocity of the coating module 3 and the time difference between the above-mentioned second measurement time and the above-mentioned first measurement time; and, based on the rotation angle and the distance from the measurement position corresponding to the target magnetic field strength measurement value in the wafer carrier surface to the connection line between the center position of the wafer and the center position of the wafer carrier surface, determine the distance between the center position of the wafer and the center position of the wafer carrier surface. The position adjustment subunit 212 is used to adjust the wafer from the wafer position to the center position of the wafer carrier surface based on the aforementioned distance and along the connection line between the center position of the wafer and the center position of the wafer carrier surface. Exemplarily, the position adjustment subunit 212 may be a linear motor, that is, the position of the wafer is adjusted by moving the wafer in one dimension.

[0069] Refer to Figure 8As shown, taking the measurement module 1 including 3 TMR sensors (i.e., TMR Sensor 1, TMR Sensor 2, and TMR Sensor 3) and the wafer carrier surface being a circular surface with a radius of r as an example. Among them, TMR Sensor 1 serves as the main sensor and can record the time (i.e., the first measurement time) when the measured magnetic field strength is the largest (i.e., the maximum magnetic field strength measurement value H m ) during the rotation process, and the time (i.e., the second measurement time) when the measured magnetic field strength is the above-mentioned preset magnetic field strength (i.e., the target magnetic field strength measurement value H t ). Thus, according to the rotational angular velocity of the coating module 3, the first measurement time, and the second measurement time, determine the rotation angle of the coating module 3 when the maximum magnetic field strength measurement value H m and the target magnetic field strength measurement value H t are measured. Exemplarily, the calculation formula for the aforementioned rotation angle can be specifically expressed as follows:

[0070] θ = ωt = ω|T1 - T2|

[0071] where θ represents the aforementioned rotation angle, ω represents the rotational angular velocity of the coating module 3, T1 represents the aforementioned first measurement time, T2 represents the aforementioned second measurement time, and || represents the absolute value operation.

[0072] Furthermore, the distance n from the intersection point between the wafer carrier surface and the wafer to the straight line where the center of the wafer carrier surface and TMR Sensor 1 are located can be determined through the rotation angle θ and the radius r of the wafer carrier surface, that is, the distance from the measurement position corresponding to the target magnetic field strength measurement value on the wafer carrier surface to the line connecting the center position of the wafer and the center position of the wafer carrier surface. Exemplarily, the calculation formula for the aforementioned distance n can be specifically expressed as: n = r·sinθ. Therefore, the calculation formula for the distance (i.e., the center distance) between the center position of the wafer and the center position of the wafer carrier surface can be specifically expressed as follows:

[0073]

[0074] where l represents the center distance between the center of the wafer and the center of the wafer carrier surface, r represents the radius of the wafer carrier surface, θ represents the aforementioned rotation angle, and n represents the aforementioned distance.

[0075] It can be seen that since only the TMR Sensor is used as the calibration main sensor, regardless of the offset of the wafer, the center of the wafer can be rotated to the intersection line between the center of the wafer bearing surface and the TMR Sensor by aligning the position with the maximum magnetic field intensity with the TMR Sensor. In this way, in the subsequent process, there is no need to use the position correction module to perform two-dimensional movement of the wafer. Only one-dimensional movement of the wafer is required to achieve the position calibration of the wafer, and the wafer is moved to the center of the wafer bearing surface.

[0076] Optionally, the first calibration unit 21 can also be used to determine that the center position of the wafer overlaps with the center position of the wafer bearing surface when multiple first magnetic field intensity measurement values all belong to the magnetic field intensity range associated with the target magnetic field intensity measurement value. In other words, when the magnetic field intensity magnitudes of multiple first magnetic field intensity measurement values are all close to the preset magnetic field intensity, it can be determined that the center position of the wafer basically overlaps with the center position of the wafer bearing surface, and there is no need to calibrate the position of the wafer.

[0077] The second calibration unit 22 included in the calibration module 2 is used to instruct the coating module 3 to drive the wafer to rotate when it is determined that the position of the wafer is the center position of the wafer bearing surface, and to determine that the coating module 3 has adjusted the notch orientation of the wafer to the preset orientation when the magnetic field intensity difference between two adjacent second magnetic field intensity measurement values is greater than the set difference threshold, and to instruct the coating module to stop rotating the wafer. The magnetic field intensity difference between the two aforementioned second magnetic field intensity measurement values being greater than the set difference threshold means that the magnetic field intensity detected by the measurement module 1 has changed suddenly when the wafer rotates to this position.

[0078] In an alternative implementation, still as Figure 7 shown, the second calibration unit 22 can include a second processing subunit 221 and a message sending subunit 222. Among them, the second processing subunit 221 is used to generate a first indication message when it is determined that the position of the wafer is the center position of the wafer bearing surface, and to generate a second indication message when the magnetic field intensity difference between two adjacent second magnetic field intensity measurement values is greater than the set difference threshold. Among them, the first indication message is used to instruct the coating module 3 to drive the wafer to rotate, and the second indication message is used to instruct the coating module 3 to stop rotating the wafer. The message sending subunit 222 is used to send the first indication information or the second indication message to the coating module 3.

[0079] Based on the above method, the second processing subunit 221 can quickly determine whether the calibration of the wafer position has been completed, and detect whether the coating module 3 has adjusted the notch orientation of the wafer to the preset orientation (that is, whether the calibration of the wafer notch orientation has been completed). Moreover, the first indication information or the second indication message can be sent to the coating module 3 through the message sending subunit 222 to control the opening or closing of the coating module 3 in a timely manner, improving the adjustment efficiency of the wafer notch orientation.

[0080] In an alternative implementation, still as Figure 5 shown, the coating module 3 may include: an electrostatic adsorption unit 31 and a rotary coating unit 32. Among them, the electrostatic adsorption unit 31 can be used to carry the wafer and form a magnetic field during the rotation of the wafer; the rotary coating unit 32 can be used to drive the wafer to rotate. Refer to the charge distribution of the electrostatic adsorption unit 31 Figure 9 shown. When the positive and negative electrodes are energized, a certain charge distribution will appear on the surface of the adsorbed wafer. Exemplarily, the rotary coating unit 32 can be a rotary motor, and the type of the rotary motor is not limited in the embodiments of the present invention.

[0081] The electrostatic adsorption unit 31 can be a planar electrostatic adsorption unit (as shown in (A) of Figure 10 ) or a spatial electrostatic adsorption unit (as shown in (B) of Figure 10 ), which is not limited in the embodiments of the present invention. Among them, the planar electrostatic adsorption unit is provided with a positive electrode and a negative electrode on the left and right respectively, and the charges on the wafer surface are distributed on both sides of the wafer according to the principle of opposite-sex attraction. The spatial electrostatic adsorption unit can be provided with two or more layers of electrodes. The positive charges in the wafer are mainly concentrated in the central area of the wafer, and the negative charges in the wafer are mainly distributed in the edge area of the wafer. Specifically, the electrostatic adsorption unit 31 can be an electrostatic chuck (ESC), which is not limited in the embodiments of the present invention.

[0082] It should be understood that since a rotational spatial movement is taken during the process of adjusting the wafer position and notch orientation, a magnetic field symmetric about the two sides of the Z axis and the positive and negative X axes can be generated. In addition, taking the spatial electrostatic adsorption unit as an example, the spatial electric field distribution of the spatial electrostatic adsorption unit on the X axis is shown in Figure 11 shown. As can be seen from Figure 11 , the spatial electric field is arranged according to a certain law, and the peak points are respectively near the center of the wafer and the electrode, and the electric field decays to a certain value at the edge.

[0083] Optionally, still as Figure 5 shown, the coating module 3 may further include an energy supply unit 33 for supplying power to the electrostatic adsorption unit 31 so that the electrostatic adsorption unit 31 forms a magnetic field during the process of driving the wafer to rotate by the rotary coating unit 32.

[0084] Based on the above structural design of the wafer calibration device, refer to Figure 12As shown, it is a front view schematic diagram of the composition structure of a wafer calibration device provided by an embodiment of the present invention. The wafer calibration device includes: three TMR sensors (i.e., TMR Sensor 1, TMR Sensor 2, and TMR Sensor 3), an energy supply module DR-V, a linear motor M1, a rotary motor M2, a wafer disk, an insulation module including an ESC, and a heating module including a radio frequency electrode. The linear motor M1, the rotary motor M2, and the energy supply module DR-V are placed outside the reaction chamber RC, and the TMR Sensor 1, TMR Sensor 2, TMR Sensor 3, the wafer disk, the insulation module, and the heating module are placed inside the RC. Among them, the TMR Sensor 1, TMR Sensor 2, and TMR Sensor 3 are deployed on the top of the RC, and the position projections on the wafer disk are referred to Figure 12 As shown, that is, the position projection points of the TMR Sensor 1, TMR Sensor 2, and TMR Sensor 3 on the wafer disk are the quarter points of the wafer edge, used to detect the changes in the electric and magnetic fields at the wafer edge to identify the spatial positions of the notch and the wafer. The linear motor M1 is used to return the wafer when the position offset of the wafer and the notch orientation are not the preset orientations according to the measurement values of the TMR Sensor 1, TMR Sensor 2, and TMR Sensor 3. The lowermost rotary motor M2 is connected to the wafer disk by a connecting rod to rotate the wafer. The energy supply device DR-V above the rotary motor powers the ESC, and the heating module is used to heat the wafer to reach the process temperature. The ESC is an electrostatic chuck unit, covered with an insulating medium on the outside, and a plurality of positive and negative electrodes are arranged inside according to the spatial electrode distribution to generate an electric field to achieve the electrostatic adsorption effect. The wafer disk realizes the lifting and rotation of the wafer.

[0085] It can be seen that, in order to cooperate with the magnetic field induction of the TMR sensor, the traditional vacuum adsorption method is no longer used, but ESC is used for adsorption. ESC does not require a complex gas path, which simplifies the system structure. At the same time, compared with the vacuum adsorption method, ESC has the advantages of fast response, low energy consumption, greater flexibility, and lighter weight. Moreover, by combining ESC with the TMR sensor, electrostatic adsorption is used to form an attraction with the wafer, and at the same time, a magnetic field is generated. Then, the TMR sensor detects the edge magnetic field of the wafer. When the rotating motor M2 rotates to drive the wafer to rotate, when the shape of the wafer edge changes, the magnetic field above the wafer will also change accordingly. At this time, the TMR sensor can quickly identify the magnetic field change, thereby judging whether the notch orientation of the wafer is in place, and immediately giving a signal to stop the rotation of the rotating motor M2, and then starting the ALD coating process on the wafer, reducing the wafer transfer process, reducing the wafer position error, and improving the operating efficiency of the system. In addition, the geometric relationship between the wafer and the wafer chuck can be obtained by rotation, and the wafer position with the maximum magnetic field value can be obtained through the change of the measurement value of the TMR sensor, so as to adjust the position of the wafer chuck center, and adjust the offset wafer chuck center to the line connecting the TMR sensor and the wafer chuck center. Since the spatial position adjustment is completed by rotation, there is no need for cumbersome two-dimensional space adjustment in the follow-up, and only the linear motor M1 needs to perform one-dimensional adjustment on the wafer, reducing the equipment volume and saving the equipment cost.

[0086] In summary, in the wafer calibration device provided in the embodiment of the present invention, since a magnetic field is formed during the process of the coating module driving the wafer to rotate, the calibration module can adjust the wafer position on the wafer bearing surface of the coating module and the notch orientation of the wafer based on multiple first magnetic field intensity measurement values obtained by the measurement module measuring the magnetic field. Furthermore, when the wafer position is adjusted to the center position of the wafer bearing surface and the notch orientation is adjusted to the preset orientation by the coating module, ALD coating is performed on the wafer. It can be seen that without adding an additional calibration module including a vision sensor during the wafer transfer process, the correction of the wafer position and the adjustment of the wafer direction can be achieved, simplifying the wafer transfer process and improving the wafer transfer efficiency.

[0087] An embodiment of the present invention also provides an ALD device, which includes the above-mentioned wafer calibration device. The following wafer coating process can be realized in this ALD device: The wafer is taken out of the wafer cassette by the SMIF module and placed in the VTM to transfer from the atmospheric environment to the vacuum environment. The wafer is taken by the TM in the VTM and directly sent into the PM. The TM is placed on the wafer chuck in the PM. At this time, the electrostatic chuck is synchronously turned on, and the electrostatic chuck adsorbs the wafer and adsorbs the wafer on the wafer chuck. An electric field and a magnetic field are formed between the electrostatic chuck and the wafer. The magnetic field affects the tunneling junction resistance of the TMR sensor and forms an induced current. The rotation standby drives the wafer to rotate one circle first, and judges whether the three TMR sensors are at stable set values (for example, a preset magnetic field intensity). If it is unstable, it means that the wafer is in an eccentric state. If the wafer is not in an eccentric state, the notch orientation of the wafer can be judged whether it has reached the preset orientation through the measured magnetic field intensity of the TMR sensor. If the preset orientation is reached, the process can be directly carried out. If the magnetic field situation obtained by the TMR sensor determines that the notch orientation of the wafer has not reached the preset orientation, the rotation motor is started to drive the wafer chuck to rotate to adjust the notch orientation of the wafer until the notch orientation of the wafer reaches the preset orientation. The electric field and magnetic field mutate due to the notch reason. When the magnetic field mutation is detected, a signal can be sent to the rotation motor, indicating that the notch orientation has reached the specified direction, and the rotation motor stops working, and the wafer calibration is completed. If the wafer is in an eccentric state, position calibration is required. By recording the time from the preset magnetic field intensity gradually increasing until the maximum magnetic field intensity, since the angular velocity of the rotation motor is fixed, the rotation angle in this process can be obtained through this time. The wafer stops rotating when it reaches the maximum magnetic field intensity. At this time, the center of the wafer, the center of the wafer chuck, and the TMR Sensor 1 are on a straight line. The center distance between the two circles can be obtained through simple geometric calculation. Further, the wafer is moved by the distance of the center distance using a linear motor, and the position calibration of the wafer can be completed. At this time, the wafer is rotated again. When the magnetic field mutation is detected, a signal can be sent to the rotation motor, indicating that the notch orientation has reached the specified direction, and the motor stops working, and the wafer calibration is completed.

[0088] It can be seen that by using the above-mentioned ALD device, wafer calibration can be realized in the chamber of the PM (i.e., the RC), which not only simplifies the device layout, reduces the cost and floor space, but also simplifies the wafer transfer link and improves the transfer efficiency.

[0089] Obviously, those skilled in the art can make various changes and modifications to the embodiments of the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these changes and modifications.

Claims

1. A wafer coating device, characterized in that: include: Measurement module, calibration module and coating module, among which, The measuring module is used to measure the magnetic field strength of the magnetic field formed in the process of the wafer being driven by the coating module to rotate, and obtain a plurality of first magnetic field strength measurement values; The calibration module is used to adjust the wafer position of the wafer on the wafer carrying surface of the coating module and adjust the notch orientation of the wafer based on the multiple first magnetic field strength measurement values; wherein the wafer position represents the center position of the wafer; The coating module is used to perform atomic deposition layer ALD coating on the wafer when the wafer position is adjusted to the center position of the wafer carrying surface and the notch orientation is adjusted to a preset orientation.

2. The device according to claim 1, characterized in that The measuring module includes a plurality of measuring units, which are evenly distributed with the center position of the wafer carrying surface as the center of the circle, and each measuring unit is used to measure the magnetic field strength of the magnetic field formed in the process of the coating module driving the wafer to rotate.

3. The device according to claim 2, characterized in that The measuring unit is a tunnel magnetoresistance (TMR) sensor.

4. The device according to claim 1, characterized in that The calibration module comprises: A first calibration unit, configured to determine a rotation angle of the coating module when the maximum magnetic field strength measurement value and the target magnetic field strength measurement value are measured based on a first measurement time of a maximum magnetic field strength measurement value included in the multiple first magnetic field strength measurement values ​​and a second measurement time of a target magnetic field strength measurement value with a magnetic field strength of a preset magnetic field strength; And, based on the distance between the center position of the wafer and the center position of the wafer carrying surface obtained by the rotation angle, the wafer is adjusted from the wafer position to the center position of the wafer carrying surface; wherein the preset magnetic field strength is the magnetic field strength of the magnetic field formed in the process of the coating module driving the wafer to rotate when the center position of the wafer overlaps with the center position of the wafer carrying surface; The second calibration unit is used to instruct the coating module to drive the wafer to rotate when it is determined that the wafer position is the center position of the wafer supporting surface, and when the magnetic field strength difference between two adjacent second magnetic field strength measurement values ​​is greater than a set difference threshold, determine that the coating module has adjusted the notch orientation of the wafer to the preset orientation, and instruct the coating module to stop rotating the wafer.

5. The device according to claim 4, characterized in that The first calibration unit is further used to determine that the center position of the wafer overlaps with the center position of the wafer carrying surface when the multiple first magnetic field strength measurement values ​​all belong to the magnetic field strength interval associated with the target magnetic field strength measurement value.

6. The device according to claim 4 or 5, characterized in that The first calibration unit comprises: a first processing subunit, configured to determine the rotation angle based on a rotation angular velocity of the coating module and a time difference between the second measurement time and the first measurement time; and determining the spacing based on a distance from a measurement position corresponding to the rotation angle and the target magnetic field strength measurement value on the wafer carrying surface to a line connecting a center position of the wafer and a center position of the wafer carrying surface; The position adjustment subunit is used to adjust the wafer from the wafer position to the center position of the wafer carrying surface based on the spacing and along the line connecting the center position of the wafer and the center position of the wafer carrying surface.

7. The device according to claim 4 or 5, characterized in that The second calibration module comprises: A second processing sub-unit is used to generate a first indication message when determining that the wafer position is the center position of the wafer carrying surface, and to generate a second indication message when the magnetic field intensity difference between the two second magnetic field intensity measurement values ​​is greater than the set difference threshold; wherein the first indication message is used to instruct the coating module to drive the wafer to rotate, and the second indication message is used to instruct the coating module to stop rotating the wafer; A message sending subunit is used to send the first indication information or the second indication message to the coating module.

8. The device according to any one of claims 1 to 4, characterized in that The coating module comprises: An electrostatic adsorption unit, used for carrying the wafer and forming the magnetic field during the rotation of the wafer; The rotary coating unit is used to drive the wafer to rotate.

9. The device according to claim 8, characterized in that The coating module also includes: The energy supply unit is used to supply power to the electrostatic adsorption unit so that the electrostatic adsorption unit forms the magnetic field when the rotary coating unit drives the wafer to rotate.

10. An atomic layer deposition (ALD) device, characterized in that: Comprising a wafer calibration device as described in any one of claims 1-9.

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