Magnetic levitation rotating device and wafer RTP heat treatment equipment

Abstract

The application provides a magnetic suspension rotating device and a wafer RTP heat treatment equipment. The magnetic suspension rotating device comprises an electromagnetic coil, a magnetic suspension assembly and a horizontal detection mechanism. The magnetic suspension assembly is accommodated in the electromagnetic coil and is used for fixing a target wafer. A control module is electrically connected with the electromagnetic coil. The horizontal detection mechanism is electrically connected with the control module and is used for emitting and receiving a detection signal in a horizontal direction. If the detection signal is blocked by the target wafer, the horizontal detection mechanism generates an angle adjustment control signal and transmits the angle adjustment signal to the control module. The control module adjusts an included angle between the magnetic suspension assembly and a vertical direction according to the angle adjustment control signal, so that the target wafer is parallel to the horizontal direction, and uniform heating of the wafer is ensured.

Description

Technical Field

[0001] This application belongs to the field of semiconductor manufacturing technology, and more specifically, relates to a magnetic levitation rotation device and a wafer RTP thermal processing equipment. Background Technology

[0002] In the wafer RTP (Rapid Thermal Processing) process, a magnetic levitation rotating component is used to drive the wafer to rotate, and then heating lamps are set at intervals between the wafer to achieve rotational heating of the wafer.

[0003] In the process of using a magnetic levitation rotating assembly to drive the wafer to rotate, the magnetic levitation rotor in the magnetic levitation rotating assembly is usually calibrated. The edge ring used to fix the wafer is mounted on the magnetic levitation rotor. In the existing technology, both the support ring and the edge ring are not calibrated. As a result, after long-term use, the deformation of the edge ring causes the wafer to be unable to rotate along the preset plane during rotation. This results in the wafer not being parallel to the heating lamp during rotation, leading to uneven heating of the wafer by the heating lamp. Summary of the Invention

[0004] The purpose of this application is to provide a magnetic levitation rotation device and a wafer RTP heat treatment equipment to solve the technical problem in the prior art where the wafer cannot rotate along a preset plane due to the deformation caused by the edge ring in the levitation rotation device.

[0005] To achieve the above objectives, a first aspect of this application is to provide a magnetic levitation rotation device, comprising:

[0006] Electromagnetic coil;

[0007] A magnetic levitation component, housed within the electromagnetic coil, is used to fix the target wafer;

[0008] The control module is electrically connected to the electromagnetic coil;

[0009] A horizontal detection mechanism, electrically connected to the control module, is used to transmit and receive detection signals in the horizontal direction, and the side of the wafer away from the magnetic levitation component is configured to be located on the detection path of the detection signal;

[0010] If the detection signal is blocked by the target wafer, the horizontal detection mechanism generates an angle adjustment control signal and transmits the angle adjustment signal to the control module. The control module adjusts the angle between the magnetic levitation component and the vertical direction according to the angle adjustment control signal so that the target wafer is parallel to the horizontal direction.

[0011] Optionally, the horizontal detection mechanism includes:

[0012] A signal transmitter is electrically connected to the control module and transmits the detection signal along the horizontal direction;

[0013] A signal receiver is electrically connected to the control module and is spaced apart from the signal receiver along the horizontal direction. The magnetic levitation component is located between the signal transmitter and the signal receiver. The signal receiver is used to receive the detection signal.

[0014] Optionally, the detection signal is an optical signal;

[0015] The signal transmitter is a laser transmitter, and the signal receiver is a laser receiver.

[0016] Optionally, the center of the target wafer is positioned on the optical path of the optical signal.

[0017] Optionally, the number of signal transmitters is multiple, and the multiple signal transmitters are evenly spaced along the circumference of the magnetic levitation component;

[0018] The number of signal receivers is multiple, and the multiple signal receivers are evenly spaced along the circumference of the magnetic levitation component. Each of the multiple signal receivers corresponds to a multiple of the signal transmitters, and each signal receiver is used to receive the detection signal emitted by the corresponding signal transmitter.

[0019] Optionally, it also includes:

[0020] The training detection module is electrically connected to the control module and the horizontal detection mechanism.

[0021] When the horizontal detection mechanism receives the detection signal, the training detection module generates a rotation control drive signal and transmits the rotation control drive signal to the control module. The control module generates a rotation control signal according to the rotation control drive signal to control the magnetic levitation component to rotate within the electromagnetic coil.

[0022] When the detection signal is blocked by the target wafer, the training detection module generates an angle adjustment control drive signal and transmits the angle adjustment control drive signal to the control module. The control module generates the angle adjustment control signal according to the rotation control drive signal.

[0023] Optionally, the magnetic levitation component has N points relative to the electromagnetic coil, where N is a positive integer, and the N points are evenly spaced along the circumference of the electromagnetic coil.

[0024] When the target wafer at the current location is parallel to the horizontal direction, the training detection module generates a rotation control drive signal and transmits the rotation control drive signal to the control module. The control module generates the rotation control signal according to the rotation control drive signal to control the magnetic levitation component to rotate to the next location.

[0025] Optionally, it also includes:

[0026] A storage module, electrically connected to the training and detection module, is used to store the angle of rotation of the magnetic levitation component relative to the vertical direction when the target wafer at each site is parallel to the horizontal direction.

[0027] Optionally, the magnetic levitation component includes:

[0028] A magnetically levitated rotor is housed within the electromagnetic coil;

[0029] A support ring is connected to the magnetically levitated rotor;

[0030] An edge ring is supported on the support ring along the vertical direction, and the edge ring is provided with a receiving groove, in which the target wafer is received.

[0031] The beneficial effects of the magnetic levitation rotation device provided in this application are as follows: Compared with the prior art, the magnetic levitation rotation device provided in this application includes an electromagnetic coil, a magnetic levitation component, and a horizontal detection mechanism. It has a housing space, the magnetic levitation component is housed in the electromagnetic coil and used to fix the target wafer, the control module is electrically connected to the electromagnetic coil, and the horizontal detection mechanism is electrically connected to the control module. It is used to transmit and receive detection signals in the horizontal direction. If the detection signal is blocked by the target wafer, the horizontal detection mechanism generates an angle adjustment control signal and transmits the angle adjustment signal to the control module. The control module adjusts the angle between the magnetic levitation component and the vertical direction according to the angle adjustment control signal so that the target wafer is parallel to the horizontal direction, thereby ensuring uniform heating of the wafer.

[0032] Secondly, this application provides a wafer RTP thermal processing apparatus, comprising:

[0033] A magnetic levitation rotating device, wherein the magnetic levitation rotating device is any one of the magnetic levitation rotating devices described above;

[0034] A heating lamp is vertically positioned above the magnetic levitation rotating device to heat the target wafer.

[0035] The beneficial effects of the wafer RTP thermal processing equipment provided in this application are as follows: Compared with the prior art, the wafer RTP thermal processing equipment provided in this application includes a heating lamp and a magnetic levitation rotation device provided by any one of the above. The magnetic levitation rotation device includes an electromagnetic coil, a magnetic levitation component, and a horizontal detection mechanism. It is provided with a receiving space. The magnetic levitation component is housed in the electromagnetic coil and is used to fix the target wafer. The control module is electrically connected to the electromagnetic coil, and the horizontal detection mechanism is electrically connected to the control module. It is used to transmit and receive detection signals in the horizontal direction. If the detection signal is blocked by the target wafer, the horizontal detection mechanism generates an angle adjustment control signal and transmits the angle adjustment signal to the control module. The control module adjusts the angle between the magnetic levitation component and the vertical direction according to the angle adjustment control signal so that the target wafer is parallel to the horizontal direction, thereby ensuring uniform heating of the wafer by the heating lamp. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is a schematic diagram of the structure of the magnetic levitation rotation device provided in the embodiments of this application;

[0038] Figure 2 This is a schematic diagram of the structure of a magnetic levitation rotation device provided in another embodiment of this application;

[0039] Figure 3 This is a front view of the magnetic levitation component provided in an embodiment of this application;

[0040] Figure 4 A perspective view of the magnetic levitation component provided in the embodiments of this application;

[0041] Figure 5 A cross-sectional view of the magnetic levitation component provided in an embodiment of this application;

[0042] Figure 6 A schematic diagram of the structure when the target wafer is set at an angle to the horizontal direction;

[0043] Figure 7 This is a schematic diagram of the magnetic levitation assembly when the target wafer is adjusted to a horizontal position.

[0044] The following are the labeling elements in the figure:

[0045] 10. Electromagnetic coil; 20. Magnetic levitation assembly; 21. Magnetic levitation rotor; 22. Support ring; 23. Edge ring; 30. Control module; 40. Horizontal detection mechanism; 41. Signal transmitter; 42. Signal receiver; 50. Training and detection module; 60. Storage module; 70. Target wafer. Detailed Implementation

[0046] To make the technical problems, technical solutions, and beneficial effects to be solved by this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and are not intended to limit the scope of this application.

[0047] It should be noted that when a component is referred to as being "fixed to" or "set on" another component, it can be directly on or indirectly on that other component. When a component is referred to as being "connected to" another component, it can be directly connected to or indirectly connected to that other component.

[0048] It should be understood that the terms "length", "width", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0049] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0050] Please refer to the following: Figures 1 to 7 The magnetic levitation rotation device and wafer RTP heat treatment equipment provided in the embodiments of this application will now be described.

[0051] The first aspect of this application is to provide a magnetic levitation rotation device, including an electromagnetic coil 10, a magnetic levitation component 20, a control module 30, and a horizontal detection mechanism 40.

[0052] Please see Figures 1 to 7 The magnetic levitation component 20 is housed within the electromagnetic coil 10 and is used to fix the target wafer 70. The control module 30 is electrically connected to the electromagnetic coil 10.

[0053] The horizontal detection mechanism 40 is electrically connected to the control module 30 and is used to transmit and receive detection signals in the horizontal direction. The side of the wafer away from the magnetic levitation component 20 is configured to be located on the detection path of the detection signal.

[0054] Since the horizontal detection mechanism 40 emits a detection signal in the horizontal direction, when the target wafer 70 is parallel to the horizontal direction, the target wafer 70 cannot block the detection signal, and the horizontal detection mechanism 40 can receive the detection signal. At this time, the control module 30 generates a rotation control signal according to the detection signal received by the horizontal detection mechanism 40, and the control module 30 changes the current in the electromagnetic coil 10 according to the rotation control signal to form an alternating magnetic field in the circumference of the electromagnetic coil 10, thereby driving the magnetic levitation component 20 to rotate in the horizontal direction within the electromagnetic coil 10, thereby realizing the rotational heating of the target wafer 70.

[0055] When the target wafer 70 forms an angle with the horizontal direction, the height of one end of the target wafer 70 along the horizontal direction is higher than the height of the other end of the target wafer 70. The higher end of the target wafer 70 will block the detection signal. At this time, the horizontal detection mechanism 40 cannot receive the detection signal. At this time, the horizontal detection mechanism 40 generates an angle adjustment control signal and transmits the angle adjustment signal to the control module 30. The control module 30 changes the current in the electromagnetic coil 10 according to the angle adjustment control signal to form an alternating magnetic field in the vertical direction of the electromagnetic coil 10, so as to adjust the angle between the magnetic levitation component 20 and the vertical direction, so that the target wafer 70 is parallel to the horizontal direction.

[0056] Compared with the prior art, the magnetic levitation rotation device provided in this application includes an electromagnetic coil 10, a magnetic levitation component 20, and a horizontal detection mechanism 40. It has a housing space, the magnetic levitation component 20 is housed in the electromagnetic coil 10 and is used to fix the target wafer 70, the control module 30 is electrically connected to the electromagnetic coil 10, and the horizontal detection mechanism 40 is electrically connected to the control module 30. It is used to transmit and receive detection signals in the horizontal direction. If the detection signal is blocked by the target wafer 70, the horizontal detection mechanism 40 generates an angle adjustment control signal and transmits the angle adjustment signal to the control module 30. The control module 30 adjusts the angle between the magnetic levitation component 20 and the vertical direction according to the angle adjustment control signal so that the target wafer 70 is parallel to the horizontal direction, thereby ensuring uniform heating of the wafer.

[0057] In this application, the horizontal detection mechanism 40 includes a signal transmitter 41 and a signal receiver 42.

[0058] Please see Figures 1 to 3The signal transmitter 41 is electrically connected to the control module 30 and transmits detection signals in a horizontal direction. The signal receiver 42 is electrically connected to the control module 30 and is spaced apart from the signal receiver 42 in a horizontal direction. The magnetic levitation component 20 is located between the signal transmitter 41 and the signal receiver 42. The signal receiver is used to receive the detection signals.

[0059] When the signal receiver 42 receives the detection signal, it generates a first electrical signal and transmits it to the control module 30. The control module 30 then generates a rotation control signal based on the first electrical signal. When the signal receiver 42 fails to receive the detection signal, it generates a second electrical signal and transmits it to the control module 30. The control module 30 then generates a rotation control signal based on the second electrical signal.

[0060] In one embodiment of this application, the detection signal is an optical signal, the signal transmitter 41 is a laser transmitter, and the signal receiver 42 is a laser receiver.

[0061] In another embodiment of this application, the signal transmitter 41 is an infrared signal transmitter and the signal receiver 42 is an infrared signal receiver.

[0062] In this application, as a preferred embodiment, when the detection signal is an optical signal, the center of the target wafer 70 is positioned on the optical path of the optical signal.

[0063] Since the target wafer 70 has the largest diameter along its radial direction, by setting the center of the target wafer 70 in the optical path of the optical signal, when the angle between the target wafer 70 and the horizontal direction is relatively small, the part of the target wafer 70 located at the high position can still block the optical signal, thereby improving the accuracy of the horizontal detection device in detecting the target wafer 70.

[0064] In one embodiment of this application, please refer to Figure 4 There are multiple signal transmitters 41, which are evenly spaced along the circumference of the magnetic levitation assembly 20. There are also multiple signal receivers 42, which are evenly spaced along the circumference of the magnetic levitation assembly 20, and each signal receiver 42 corresponds to one of the multiple signal transmitters 41. Each signal receiver 42 is used to receive the detection signal emitted by the corresponding signal transmitter 41.

[0065] By circumferentially arranging multiple sets of signal transmitters 41 and signal receivers 42 in the magnetic levitation assembly 20, the multiple sets of signal transmitters 41 and signal receivers 42 simultaneously transmit detection signals along the radial direction of the target wafer 70 and passing through the center of the target wafer 70, thereby improving the detection accuracy of the target wafer 70 along the circumference of the magnetic levitation assembly 20.

[0066] In one embodiment of this application, the magnetic levitation rotation device further includes a training and detection module 50.

[0067] In this embodiment, please refer to Figure 2 , Figure 6 and Figure 7 The training and detection module 50 is electrically connected to the control module 30 and the level detection mechanism 40.

[0068] When the horizontal detection mechanism 40 receives the detection signal, the training detection module 50 generates a rotation control drive signal and transmits the rotation control drive signal to the control module 30. The control module 30 controls the magnetic levitation component 20 to rotate within the electromagnetic coil 10 according to the rotation control signal.

[0069] When the detection signal is blocked by the target wafer 70, the training detection module 50 generates an angle adjustment control drive signal and transmits the angle adjustment control drive signal to the control module 30. The control module 30 adjusts the angle between the magnetic levitation component 20 and the vertical direction according to the angle adjustment control drive signal, so as to adjust the target wafer 70 to be parallel to the horizontal direction.

[0070] Specifically, when the horizontal detection mechanism 40 does not receive a detection signal, the signal receiver 42 transmits a first electrical signal to the training detection module 50. The training detection module 50 receives the first electrical signal and generates a rotation control drive signal based on the first electrical signal. The training detection module 50 transmits the rotation control drive signal to the control module 30 so that the control module 30 controls the magnetic levitation component 20 to rotate in the horizontal direction within the electromagnetic coil 10.

[0071] When the horizontal detection mechanism 40 receives the detection signal, the signal receiver 42 transmits the second electrical signal to the training detection module 50. The training detection module 50 receives the second electrical signal and generates an angle adjustment control drive signal according to the second electrical signal. The training detection module 50 transmits the angle adjustment control drive signal to the control module 30 so that the control module 30 controls the magnetic levitation component 20 to rotate relative to the electromagnetic coil 10 in the vertical direction.

[0072] In one embodiment of this application, the magnetic levitation component 20 has N points relative to the electromagnetic coil 10, where N is a positive integer, and the N points are evenly spaced along the circumference of the electromagnetic coil 10. When the target wafer 70 at the current point is parallel to the horizontal direction, the training detection module 50 generates a rotation control drive signal and transmits the rotation control drive signal to the control module 30. The control module 30 generates a rotation control signal according to the rotation control drive signal and controls the magnetic levitation component 20 to rotate by a preset angle to the next point, wherein the preset angle is the ratio of 360° to N.

[0073] By setting N points around the circumference of the electromagnetic coil 10, and adjusting the target wafer 70 to be parallel to the horizontal direction at each point, the target wafer 70 is made to be parallel to the horizontal direction in the radial direction.

[0074] In this application, the value of N is any value from 1 to 360, such as 30.

[0075] In one embodiment of this application, the magnetic levitation rotating device further includes a storage module 60.

[0076] The storage module 60 is electrically connected to the training and detection module 50 and is used to store the angle of rotation of the magnetic levitation component 20 relative to the vertical direction when the target wafer 70 at each site is parallel to the horizontal direction.

[0077] Specifically, when the target wafer 70 is adjusted to be parallel to the horizontal direction at each site, the storage module 60 stores the angle of rotation of the magnetic levitation component 20 at that site relative to the vertical direction, and performs the above operation for each site.

[0078] At all locations, the angle of rotation of the magnetic levitation component 20 relative to the vertical direction is stored, and the training and detection module 50 calculates the motion path of the magnetic levitation component 20 between any two adjacent locations, so that the magnetic levitation component 20 rotates relative to the electromagnetic coil 10 along the shortest motion path between any two adjacent locations, and the stored path stores the motion path of the magnetic levitation component 20 between any two adjacent locations, so as to facilitate rapid leveling of the next target wafer 70.

[0079] In this application, the magnetic levitation assembly 20 includes a magnetic levitation rotor 21, a support ring 22, and an edge ring 23.

[0080] Please see Figures 3 to 5 The magnetic levitation rotor 21 is housed within the electromagnetic coil 10, and the support ring 22 is connected to the magnetic levitation rotor 21. The edge ring 23 is supported vertically on the support ring 22, and the edge ring 23 is provided with a receiving groove 231, in which the target wafer 70 is housed.

[0081] A second aspect of this application is to provide a wafer RTP thermal processing apparatus, including a magnetic levitation rotating device and a heating lamp 80.

[0082] Please see Figure 1 and Figure 2 The magnetic levitation rotation device is the magnetic levitation rotation device provided in any of the above embodiments. The heating lamp 80 is arranged vertically above the magnetic levitation rotation device and extends horizontally for heating the target wafer 70.

[0083] Compared with the prior art, the wafer RTP thermal processing equipment provided in this application includes a heating lamp and a magnetic levitation rotation device provided by any of the above. The magnetic levitation rotation device includes an electromagnetic coil 10, a magnetic levitation component 20 and a horizontal detection mechanism 40, and is provided with a receiving space. The magnetic levitation component 20 is housed in the electromagnetic coil 10 and is used to fix the target wafer 70. The control module 30 is electrically connected to the electromagnetic coil 10, and the horizontal detection mechanism 40 is electrically connected to the control module 30 and is used to transmit and receive detection signals in the horizontal direction. If the detection signal is blocked by the target wafer 70, the horizontal detection mechanism 40 generates an angle adjustment control signal and transmits the angle adjustment signal to the control module 30. The control module 30 adjusts the angle between the magnetic levitation component 20 and the vertical direction according to the angle adjustment control signal so that the target wafer 70 is parallel to the horizontal direction, thereby ensuring uniform heating of the wafer by the heating lamp.

[0084] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application.

Claims

1. A magnetic levitation rotation device, characterized in that, include: Electromagnetic coil; A magnetic levitation component, housed within the electromagnetic coil, is used to fix the target wafer; The control module is electrically connected to the electromagnetic coil; A horizontal detection mechanism, electrically connected to the control module, is used to transmit and receive detection signals in the horizontal direction, and the side of the wafer away from the magnetic levitation component is configured to be located on the detection path of the detection signal; If the detection signal is blocked by the target wafer, the horizontal detection mechanism generates an angle adjustment control signal and transmits the angle adjustment signal to the control module. The control module adjusts the angle between the magnetic levitation component and the vertical direction according to the angle adjustment control signal so that the target wafer is parallel to the horizontal direction.

2. The magnetic levitation rotation device as described in claim 1, characterized in that, The horizontal detection mechanism includes: A signal transmitter is electrically connected to the control module and transmits the detection signal along the horizontal direction; A signal receiver is electrically connected to the control module and is spaced apart from the signal receiver along the horizontal direction. The magnetic levitation component is located between the signal transmitter and the signal receiver. The signal receiver is used to receive the detection signal.

3. The magnetic levitation rotation device as described in claim 2, characterized in that, The detection signal is an optical signal; The signal transmitter is a laser transmitter, and the signal receiver is a laser receiver.

4. The magnetic levitation rotation device as described in claim 3, characterized in that, The center of the target wafer is positioned on the optical path of the optical signal.

5. The magnetic levitation rotation device as described in claim 4, characterized in that, The number of signal transmitters is multiple, and the multiple signal transmitters are evenly spaced along the circumference of the magnetic levitation component; The number of signal receivers is multiple, and the multiple signal receivers are evenly spaced along the circumference of the magnetic levitation component. Each of the multiple signal receivers corresponds to a multiple of the signal transmitters, and each signal receiver is used to receive the detection signal emitted by the corresponding signal transmitter.

6. The magnetic levitation rotation device as described in claim 1 or 5, characterized in that, Also includes: The training detection module is electrically connected to the control module and the horizontal detection mechanism. When the horizontal detection mechanism receives the detection signal, the training detection module generates a rotation control drive signal and transmits the rotation control drive signal to the control module. The control module generates a rotation control signal according to the rotation control drive signal to control the magnetic levitation component to rotate within the electromagnetic coil. When the detection signal is blocked by the target wafer, the training detection module generates an angle adjustment control drive signal and transmits the angle adjustment control drive signal to the control module. The control module generates the angle adjustment control signal according to the rotation control drive signal.

7. The magnetic levitation rotation device as described in claim 6, characterized in that, The magnetic levitation component has N points relative to the electromagnetic coil, where N is a positive integer, and the N points are evenly spaced along the circumference of the electromagnetic coil. When the target wafer at the current location is parallel to the horizontal direction, the training detection module generates a rotation control drive signal and transmits the rotation control drive signal to the control module. The control module generates the rotation control signal according to the rotation control drive signal to control the magnetic levitation component to rotate to the next location.

8. The magnetic levitation rotation device as described in claim 7, characterized in that, Also includes: A storage module, electrically connected to the training and detection module, is used to store the angle of rotation of the magnetic levitation component relative to the vertical direction when the target wafer at each site is parallel to the horizontal direction.

9. The magnetic levitation rotation device as described in claim 1, characterized in that, The magnetic levitation component includes: A magnetically levitated rotor is housed within the electromagnetic coil; A support ring is connected to the magnetically levitated rotor; An edge ring is supported on the support ring along the vertical direction, and the edge ring is provided with a receiving groove, in which the target wafer is received.

10. A wafer RTP thermal processing device, characterized in that, include: A magnetic levitation rotating device, wherein the magnetic levitation rotating device is the magnetic levitation rotating device according to any one of claims 1-9; A heating lamp is vertically positioned above the magnetic levitation rotating device to heat the target wafer.

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