KR102424176B1 - Magnetic levitation rotating apparatus and aparatus for vacuum processing including the same - Google Patents

Abstract

The present invention relates to a magnetically levitated rotating apparatus and a vacuum processing apparatus including the same, and more specifically, to a magnetically levitated rotating apparatus having a rotation part capable of rotating stably while being levitated and a vacuum processing apparatus including the same. The magnetically levitated rotating apparatus according to an embodiment of the present invention comprises: a housing part connected to a chamber part to form a vacuum space; a cylindrical rotation part accommodated in the inner space of the housing part and levitated by a magnetic force to rotate about a rotational axis; a fixing part provided on the outside of the housing part to provide a magnetic force to the rotation part; a horizontal displacement sensor part for measuring the horizontal displacement of the rotation part; a vertical displacement sensor part mounted on a bottom surface of the housing part to measure the vertical displacement of the rotation part; and a velocity sensor part provided outside the housing part to measure the rotating velocity of the rotation part, wherein the velocity sensor part may include a first velocity sensor and a second velocity sensor provided at different heights.

Description

Magnetic levitation rotating apparatus and vacuum processing apparatus including the same

The present invention relates to a magnetic levitation rotating apparatus and a vacuum processing apparatus including the same, and more particularly, to a magnetically levitated rotating apparatus capable of stably rotating a magnetically levitated rotating part and a vacuum processing apparatus including the same.

In recent semiconductor devices, the thickness of the thin film constituting the semiconductor device is only a few nanometers (nm), and the thickness uniformity must be maintained within several%. This level of uniformity necessitates the requirement that the temperature change across the substrate during high temperature processing cannot exceed several degrees Celsius. Therefore, a technique for minimizing the temperature non-uniformity is very important. In particular, as the size of the substrate increases, uniform heating is not performed properly, causing many problems. In order to solve the problem of uniform heating of the substrate, there is a magnetic levitation rotating apparatus as a substrate rotating apparatus for horizontally rotating the substrate while the rapid heat treatment is performed.

The magnetically levitated rotating device includes a fixed part (Stator) and a rotating part (Rotor), and the rotating part is levitated and rotates in a non-contact state with the fixed part by magnetic force. Therefore, there is little noise and vibration, there is no generation of particles, and high-speed rotation is possible, so it is suitable for a rapid heat treatment device that is heated to a high temperature for a short time. The rotating part supports the edge ring through the support cylinder, and the substrate is placed on the edge ring.

In general, a semiconductor process for forming a semiconductor device is performed in a vacuum state. The rotating part for rotating the substrate should be located inside a vacuum space maintained in a vacuum state, while the stationary part should be located in an external space maintained at atmospheric pressure. Since the fixed part and the rotating part rotate due to the interaction of the magnetic field, the housing part between the fixed part and the rotating part should be thin so that a magnetic field can pass through the housing part defining a vacuum space together with the chamber part. When the vacuum is maintained for semiconductor processing due to the thin housing part, an error may occur in the position measurement of the rotating part due to the distortion of the shape of the housing part. There is an increasing problem.

Patent Publication No. 10-2001-0111030

The present invention provides a magnetic levitation rotating device capable of stable magnetically levitated rotation of the rotating unit and a vacuum processing apparatus including the same.

In addition, the present invention provides a magnetic levitation rotating device capable of stably controlling the rotational speed of the rotating unit and a vacuum processing device including the same.

Magnetic levitation rotating device according to an embodiment of the present invention is connected to the chamber portion housing to form a vacuum space; a cylindrical rotating part accommodated in the inner space of the housing part and levitating by magnetic force to rotate about a rotating shaft; a fixing part provided on the outside of the housing part to provide a magnetic force to the rotating part; a horizontal displacement sensor for measuring the horizontal displacement of the rotating part; a vertical displacement sensor unit mounted on a bottom surface of the housing unit to measure a vertical displacement of the rotating unit; and a speed sensor provided outside the housing to measure the rotational speed of the rotating unit, wherein the speed sensor may include a first speed sensor and a second speed sensor provided at different heights.

The housing portion includes a cylindrical inner wall connected to each other with the bottom portion interposed therebetween; and a cylindrical outer wall provided on the outside of the inner wall, wherein the rotating part is accommodated between the inner wall and the outer wall of the housing part, and the thickness of the outer wall is thinner than the thickness of the inner wall and the thickness of the bottom part can

The first speed sensor and the second speed sensor may be arranged side by side in a vertical direction.

The first and second speed sensors may be Hall sensors.

The speed sensor unit includes: a fixing bar for fixing the first speed sensor and the second speed sensor, and made of a ferromagnetic material; and a first permanent magnet part on which the fixed bar part is supported.

The first speed sensor and the second speed sensor may be mounted and fixed to an outer circumferential surface of the fixed bar, and a cross-section of the fixed bar may be circular.

The first speed sensor and the second speed sensor may be provided to be spaced apart from each other.

The rotating part may include a plurality of protrusions provided along an outer circumferential surface of the upper end or lower end, and a separation distance between the first speed sensor and the second speed sensor may be less than or equal to twice the thickness of the outer end of the plurality of protrusions.

The rotating portion includes first to second flange portions extending outwardly from the outer circumferential surface to be spaced apart from each other, and wherein the fixing portion includes first to second flange portions spaced apart from each other to face the first to second flange portions. 2 magnetic core plate; a second permanent magnet part provided between the first bet and the second magnetic core plate to generate an attraction force to the rotating part; and a position control coil wound around a portion of the first to second magnetic core plates to control the position of the rotating part by adjusting the suction force according to the direction and magnitude of the current generating magnetic flux; It may be supported on any one plane of the first to second magnetic core plates.

The fixing part may include a cover part connected to any one of the first to second magnetic core plates and made of a non-magnetic material; a driving core part connected to the cover part so as to be spaced apart from the first to second magnetic core plates and made of a ferromagnetic material; a plurality of driving coil units wound around a portion of the driving core unit to provide rotational driving force to the rotating unit; and a holder part connected to the cover part and fixing the upper part of the speed sensor part.

It may further include; a control unit for controlling the rotation speed of the rotation unit using the average value of the rotation speed of the rotation unit measured by the first to second speed sensors, respectively.

A vacuum processing apparatus according to another embodiment of the present invention is a magnetic levitation rotating device according to an embodiment of the present invention; a chamber part connected to the housing to form a vacuum space; and an exhaust unit for evacuating the vacuum space.

And, a substrate support provided to support the substrate provided in the vacuum space and to be rotatable in connection with the rotating unit; a heat source provided on the first surface side of the substrate to provide thermal energy toward the substrate; and a temperature measuring unit provided on the second surface side of the substrate to measure the temperature of the substrate.

According to the magnetic levitation rotating device and the vacuum processing device according to an embodiment of the present invention, it is possible to accurately measure the rotational speed of the rotating part even in a vacuum state, and stably controlling the magnetically levitated rotational speed of the rotating part using the accurately measured rotational speed Due to this, it is possible to effectively suppress the occurrence of a speed hunting phenomenon or a speed ripple phenomenon, and it may be possible to stop the rotating part.

And, the rotation speed can be measured stably regardless of atmospheric pressure and vacuum, so that the rotation speed can be easily controlled regardless of the pressure in the chamber.

In addition, it is possible to effectively suppress vibration and noise that may be generated during unstable rotation of the rotating unit, and appropriately manage the load applied to the electromagnet used for horizontal position movement of the rotating unit, thereby stably controlling the rotating speed of the rotating unit.

On the other hand, in the case of a rotating object (eg, a semiconductor wafer) that is connected to a rotating part and rotates together, it may be caused by unstable rotation due to the rotational speed hunting phenomenon of the rotating part. Problems can be effectively suppressed.

1 is a conceptual diagram of a magnetic levitation rotating device according to an embodiment of the present invention.
Figure 2 is a plan view of a magnetic levitation rotating device according to an embodiment of the present invention.
Figure 3 is a partial cut-away perspective view of the magnetic levitation rotating device according to an embodiment of the present invention.
Figure 4 is a partial cross-sectional view of a magnetic levitation rotating device according to an embodiment of the present invention.
5 is a conceptual diagram illustrating a change in rotational speed depending on whether a vacuum is used in a vacuum processing apparatus.
6 is a graph showing a change in rotational speed depending on whether or not there is a vacuum in the vacuum processing apparatus.
7 is a rotational speed graph of the magnetic levitation rotating device according to an embodiment of the present invention.
8 is a conceptual diagram of a vacuum processing apparatus according to another embodiment of the present invention.

Hereinafter, embodiments of the present invention will be described in more detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiments disclosed below, but will be implemented in a variety of different forms, only these embodiments allow the disclosure of the present invention to be complete, and the scope of the invention to those of ordinary skill in the art completely It is provided to inform you. In the description, the same reference numerals are assigned to the same components, and the sizes of the drawings may be partially exaggerated in order to accurately describe the embodiments of the present invention, and the same reference numerals refer to the same elements in the drawings.

Figure 1 is a conceptual diagram of a magnetic levitation rotary device according to an embodiment of the present invention, Figure 2 is a plan view of a magnetically levitated rotary device according to an embodiment of the present invention, Figure 3 is a magnetically levitated rotary device according to an embodiment of the present invention A partial cut-away perspective view of, Figure 4 is a partial cross-sectional view of the magnetic levitation rotating device according to an embodiment of the present invention. At this time, FIGS. 3 and 4 are views showing a portion cut along the line A-A' in FIG. 2 .

1 to 4, the magnetic levitation rotating device according to an embodiment of the present invention, the housing portion 100 is connected to the chamber portion 600 to form a vacuum space (V); a cylindrical rotating unit 200 accommodated in the inner space of the housing unit 100 and levitated by magnetic force to rotate about a rotating shaft; a fixing part 300 provided on the outside of the housing part 100 to provide a magnetic force to the rotating part 200; a horizontal displacement sensor unit 410 for measuring the horizontal displacement of the rotating unit 200; a vertical displacement sensor unit 420 mounted on the bottom of the housing unit 100 to measure the vertical displacement of the rotating unit; and a speed sensor unit 500 provided on the outside of the housing unit 100 to measure the rotation speed of the rotating unit 200 . In addition, the speed sensor unit 500 includes a first speed sensor 510 provided at different heights; and a second speed sensor 520 .

The housing 110 separates the rotating part 200 accommodated therein and the fixing part 300 provided to the outside from each other, and is connected to a chamber part 600 of a vacuum processing apparatus to be described later in a vacuum space separated from the outside ( V) can be defined. The inside of the housing part 100 may be maintained in a vacuum while it is connected to the chamber part 600 of the vacuum processing apparatus and the vacuum processing process is in progress, so that it can withstand the pressure difference between the external atmospheric pressure and the internal vacuum pressure. should have

The cylindrical rotating part 200 is accommodated in the inner space of the housing part, floats by magnetic force, and can rotate about a rotating shaft. The magnetic force for levitating and rotating the rotating part 200 is provided by the fixing part 300 disposed on the outside of the housing part 100, so that the interaction of the magnetic field between the rotating part 200 and the fixing part 300 is smooth. In order to do this, the cylindrical rotating part 200 may include first to second flange parts 220 and 230 that extend outwardly from the outer circumferential surface 210 and are provided to be spaced apart from each other. The rotating unit 200 may be made of a ferromagnetic material so that a strong magnetic field can be induced by the fixing unit 300 , and provided along the outer peripheral surface 210 of the upper end or lower end of the cylindrical rotating unit 200 and spaced apart at a predetermined distance. The protrusion 240 of the may include a pole tooth or pole tooth (tooth) arranged in a ring shape.

The fixing part 300 may be provided on the outside of the housing part 100 to provide a magnetic force necessary for the levitation and movement of the rotating part 200 .

The fixing part 300 includes first and second magnetic core plates 310, which are provided spaced apart from each other in the vertical (Z-axis) direction to face the first and second flange parts 220 and 230 of the rotating part 200 , 320); and a second permanent magnet unit 330 provided between the first and second magnetic core plates 310 and 320 to generate an attraction force to the rotating unit 200 .

The first and second magnetic core plates 310 and 320 are integral flat plates extending along the outer circumferential surface of the cylindrical rotating part 200 and constitute a radial closed circuit, and may include radially symmetrically provided protrusions. .

A plurality of second permanent magnet units 330 may be provided at equal intervals in the horizontal (X-axis and Y-axis) direction. Since the second permanent magnet unit 330 has a strong magnetic field, it can generate a strong magnetic field in the rotating unit 200 despite the presence of a gap of air or vacuum, thereby levitating the rotating unit 020 as well as The rotating part 200 allows the center of the second permanent magnet part 330 to be aligned in the vertical direction.

The fixing unit 30 may further include a driving coil 360 and position control coils 341 , 342 , and 343 for generating magnetic flux by an input current.

The driving coil 360 is a multi-phase winding in which a plurality of end windings are arranged at equal intervals along the inner surface of the driving core part 350 , and the pole teeth or It interacts with the magnetic field of the magnetic pole teeth to generate a torque centered on the rotation axis to generate a rotational electromagnetic field or rotational driving force that rotates the rotating part 200 .

On the other hand, the magnetic flux of the second permanent magnet unit 330 generates a radial attraction force between the fixed portion 300 and the rotating portion 200, and this attraction force generates instability depending on the direction to move the rotating portion 200 to one side. can do it In this case, it is necessary to control the position of the rotating unit 200. The position of the rotating unit 200 can be controlled by using a position control coil that adjusts the suction force according to the direction and magnitude of the current generating magnetic flux. The position of the rotating part may be controlled by additionally generating or offsetting the attractive force depending on whether the relative directions of the magnetic flux of the second permanent magnet unit 330 and the magnetic flux of the position control coil coincide or are opposite to each other. The position control coil includes: a horizontal position control coil 341 for controlling the horizontal position of the rotating unit 20 by adjusting the suction force according to the direction and magnitude of the current generating magnetic flux; and a tilt control coil 342 for controlling the tilt of the rotating unit 200 by adjusting the suction force according to the direction and magnitude of the current generating magnetic flux.

The fixing part 130 is a plurality of magnet assemblies arranged in pairs symmetrically about the vertical axis along a plurality of horizontal axes (eg, X-axis and Y-axis) intersecting the vertical axis (Z-axis). may include. The plurality of magnet assemblies may be provided at positions corresponding to the protrusions of the first and second magnetic core plates 310 and 320 that are provided symmetrically in a radial direction.

Each of the plurality of magnet assemblies may include; have.

The plurality of second permanent magnet parts 330 are provided radially symmetrically and are disposed on an outer circumferential surface between regions in which protrusions of the first to second magnetic core plates 310 and 320 are provided and are provided to be vertically spaced apart.

The horizontal position control coil 341 and the inclination control coil 342 may be wound on the protrusion of the first magnetic core plate 310 and the protrusion of the second magnetic core plate 320 provided to be spaced apart from each other in the vertical direction, respectively. .

Magnetic flux direction and magnetic flux of the second permanent magnet unit 330 , the horizontal position control coil 341 , and the tilt control coil 342 , which are disposed symmetrically to each other in the X-axis and Y-axis directions about the vertical axis (rotation axis) As the size is relatively changed, horizontal position control and tilt control of the rotating unit 200 are possible.

The fixing part 300 extends along the housing part 100 and is provided to surround the housing part 100 , and a vertical position to control the vertical position of the rotating part 200 according to the direction and magnitude of a current generating magnetic flux. A control coil 343 may be further included. The rotating unit 200 is subjected to a downward force by its own weight, so that the floating rotating unit 200 cannot vertically align the height of the permanent magnet, and may be struck downwards from its original position. In this case, when rotating at a high speed, the rotating part may oscillate while rotating due to the interaction between the magnetic force and gravity caused by the permanent magnet. Therefore, it is necessary to control the vertical position of the rotating unit 200 so that the rotating unit 200 can be positioned at a desired height as needed. By doing so, it is possible to control the vertical position of the rotating unit 200 .

Meanwhile, in order to adjust the position of the rotating unit 200 using the position control coils 341 , 342 , and 343 , it is necessary to measure the position or displacement of the rotating unit 200 . In order to control the horizontal position, inclination, and vertical position of the rotating part, the horizontal position and the vertical position of the rotating part must be obtained by using a plurality of displacement sensor units 400 spaced apart from each other.

A plurality of horizontal displacement sensor units 410 may be provided inside or outside the rotating unit to measure the horizontal displacement of the rotating unit 200 .

A plurality of vertical displacement sensor units 420 may be mounted on the bottom surface portion 110 of the housing unit 100 to measure the vertical displacement of the rotating unit 200 . A plurality of vertical displacement sensor units 420 spaced at equal intervals from each other measure the position or displacement of the lower end of the rotating unit 200 that rotates while floating from the upper side. You can know the inclination and vertical position (height) of the rotating part by using it.

The speed sensor unit 500 may be provided outside the housing unit 100 to measure the rotational speed of the rotating unit 200 . When the speed sensor unit 500 is disposed to face the magnetic pole teeth or magnetic pole teeth formed by the plurality of protrusions 240 provided on the outer peripheral surface of the upper end or lower end of the rotating unit 200, the rotating unit 200 according to the rotation of the rotating unit 200 ) and the speed sensor unit 500 change, so the change in electromagnetic characteristics induced by the distance change can be detected over time to measure the rotational speed of the rotating unit.

The speed sensor unit 500 may include a Hall sensor. The Hall sensor linearly outputs an output value according to the magnitude change (ie, distance change) of the magnetic flux density (Gaussian) emitted from the magnet, from which displacement or distance can be measured. That is, the Hall sensor generates a bias magnetic field and senses the change in magnetic flux density according to the distance to the rotating part 200 made of a ferromagnetic material as a target and outputs an analog output value (voltage value or current value). (110) It is possible to measure the displacement or distance of the rotating part 200 located inside.

The housing part 100 includes a cylindrical inner wall 120 connected to each other with the bottom part 110 interposed therebetween; and a cylindrical outer wall 130 provided on the outside of the inner wall 120 . The rotating part 200 is accommodated between the inner wall 120 and the outer wall 130 of the housing part, and the thickness of the outer wall 130 may be thinner than the thickness of the inner wall 120 and the thickness of the bottom portion 130 .

The outer wall 130 is provided between the rotating part 200 and the fixing part 300 so that a magnetic force line between the rotating part 200 and the fixing part 300 can sufficiently pass through and can be made of a thin plate having a thin thickness. On the other hand, since the inner wall 120 and the bottom surface 110 do not need to pass the magnetic force line, they may be thicker than the outer wall 130 for the strength of the overall housing structure as well as to withstand the pressure difference between atmospheric pressure and vacuum pressure. And, in order for the magnetic flux of the fixing part 300 and the rotating part 200 to pass through the outer wall 130 without loss, the outer wall 130 is made of at least one of a paramagnetic material, a non-magnetic material, and a diamagnetic material, or a compound thereof. may be made, and the thickness may be 0.5 to 2.5 mm. When the thickness of the outer wall 130 is thinner than 0.5 mm, the loss of magnetic flux can be minimized, but it cannot withstand the pressure difference between atmospheric pressure and vacuum pressure, so that the shape of the housing cannot be maintained, and the thickness of the outer wall 130 is 2.5 If it is thicker than mm, it is structurally stabilized, but the magnetic force line cannot pass through the outer wall. On the other hand, when the outer wall 130 is made of a ferromagnetic material, the magnetic flux of the fixed part and the rotating part cannot pass through the outer wall, and when made of a non-magnetic material such as STS316 or SUS304, the magnetic flux of the fixed part and the rotating part can pass through without loss. there will be

The inner wall 120 and the bottom surface part 110 have sufficient thickness, so that the horizontal displacement sensor part 410 and the vertical displacement sensor part 420 have holes formed in the inner wall 120 and the bottom surface part 110 of the housing part, respectively. In order to prevent air or gas leakage due to the pressure difference between the vacuum pressure inside the housing and the atmospheric pressure outside the housing, when the magnetic levitation rotating device is connected to the chamber of the substrate processing apparatus, an O-ring is installed. It is sealed and assembled with a sealing member.

5 is a conceptual diagram illustrating a change in rotational speed depending on whether a vacuum is used in a vacuum processing apparatus.

Referring to FIG. 5 , when the vacuum space formed by connecting the chamber unit 600 and the housing unit 100 to each other is maintained at atmospheric pressure, the shape of the chamber unit 600 and the housing unit 100 may be maintained as it is. , when the pressure of the vacuum space V changes from atmospheric pressure to a vacuum state, the shapes of the chamber part 600 and the housing part 100 may be partially changed. The outer wall 130 is a part having the thinnest thickness among the chamber part and the housing part, and when the vacuum space changes to a vacuum state, it is squashed inward due to the pressure difference, and when the vacuum space changes back to atmospheric pressure, the shape returns to its original shape. can be

When a phenomenon occurs in which the outer wall 130 is crushed inward in a vacuum state, the bottom surface portion 110 integrally connected with the outer wall 130 also rises upward by several micrometers to several hundred micrometers according to the shape change of the outer wall 130. can be The rising height of the bottom part 110 may be changed according to the degree of vacuum of the vacuum space (V).

Since the vertical displacement sensor unit 420 for measuring the vertical displacement of the rotating part is mounted on the bottom surface part 110 of the housing part, when the vacuum space V changes to a vacuum state, the vertical displacement sensor part 420 is vertical as the bottom part 110 rises. The height of the displacement sensor unit 420 is also increased. The magnetic levitator of the fixing unit 300 controls the vertical direction (ie, the Z-axis direction) according to the height of the rotating unit 200 measured by the vertical displacement sensor unit 420 , the vertical displacement sensor unit 420 . Since the height of itself is changed, the target reference value (target reference, set point, or offset value) in the vertical direction is changed, so that the height of the rotating part 200 is also increased by several to several hundred µm.

On the other hand, since the speed sensor unit 500 is provided on the outside of the housing unit, it is possible to always maintain a constant height regardless of the pressure in the vacuum space. Accordingly, a relative height difference between the rotation unit 200 and the speed sensor unit 500 may occur in a vacuum state. The speed sensor unit 500 and the magnetic pole teeth formed by the plurality of protrusions 240 are arranged to face each other to measure the rotational speed of the rotating unit 200, and the rotation unit (or the magnetic pole teeth of the rotating unit) and the speed sensor unit are disposed to face each other. When the height difference occurs, the sensitivity of the speed sensor unit 500 is changed, so that it is impossible to accurately measure the rotation speed. That is, the speed sensor unit 500 including the Hall sensor measures the vector value of the magnetic flux coming out of the protrusion (or the pole tooth of the rotating part) of the rotating part. Since the vector value of is changed, the speed sensor unit cannot perform accurate measurement.

6 is a graph showing a change in rotational speed according to whether the vacuum space S is vacuumed in the vacuum processing apparatus, wherein the speed sensor unit 500 rotates the rotation unit 200 with only one speed sensor, that is, the first speed sensor 510. It is a graph of rotational speed change with respect to time measured speed.

When the vacuum space V is maintained at atmospheric pressure, when the rotational speed of the rotating part 200 is measured as shown in FIG. can check that On the other hand, when the vacuum space V is changed to a vacuum state, as in FIG. 6(b) , the rotational speed of the rotating part 200 rapidly fluctuates even in a normal state after a certain time has elapsed. Speed hunting or speed ripple It can be seen that the rotating part rotates unstable while the phenomenon is displayed. When the speed hunting phenomenon occurs, the rotation of the rotating part is unstable and not normally stopped, and the rotating object (eg, a wafer) connected to the rotating part and rotating may be pushed in the rotational or radial direction.

To solve this problem, the speed sensor unit 500 may include a first speed sensor 510 and a second speed sensor 520 provided at different heights.

A first speed sensor 510 and a first speed sensor 510 provided at different heights to suppress abnormal rotation of the rotating part 200 having different heights depending on when the vacuum space V is maintained at atmospheric pressure and when maintained in a vacuum state 2 An average value of the rotational speeds of the rotational part 200 measured by the speed sensor 520 may be used as the rotational speed of the rotational part 200 . That is, even if the height of the rotating unit 200 is changed, the respective rotational speeds measured by the first speed sensor 510 and the second speed sensor 520 are increased or decreased complementary to each other, so that the first speed sensor ( 510) and the average value of the rotational speeds measured by the second speed sensor 520, respectively, may be an accurate rotational speed of the rotating part regardless of a change in the height of the rotating part.

The first speed sensor 51 and the second speed sensor 520 may be arranged side by side in the vertical direction. In this case, they may be Hall sensors.

In order to obtain an accurate rotational speed of the rotational part using the average value of each rotational speed measured by the first speed sensor 510 and the second speed sensor 520, the Since it is necessary to obtain a sensing output value for , the first speed sensor 51 and the second speed sensor 520 may be arranged side by side in the vertical direction.

The speed sensor unit may be supported on any one plane of the first to second magnetic core plates.

In addition, the speed sensor unit 500 is fixed to the first speed sensor and the second speed sensor, the fixed bar portion 530 made of a ferromagnetic material; and a first permanent magnet part 540 on which the fixing bar part 530 is supported. In this case, the first permanent magnet unit 540 may be fixedly supported on any one plane of the first to second magnetic core plates.

Separately from the magnetic circuit between the rotating unit 200 and the fixed unit 300 for levitating, moving and rotating the rotating unit 200, a first speed sensor and a second speed sensor using the first permanent magnet unit 540 can configure a magnetic path through which a signal can be input. The magnetic circuit by the first permanent magnet unit 54 input to the first speed sensor and the second speed sensor faces the plurality of protrusions 240 of the rotating part. That is, the magnetic circuit includes the first permanent magnet part 54 , the second magnetic core plate (or the first magnetic core plate), the second flange part (or the first flange part), the outer peripheral surface 210 of the rotating part, and the protrusion part 240 . ), the first to second speed sensors 510 and 520 , the fixed rod part 530 , and the path of the first permanent magnet part 54 or the path in the reverse order according to the magnetic pole of the first permanent magnet part 540 . make up

Meanwhile, the first speed sensor 510 and the second speed sensor 520 may be mounted and fixed to the outer circumferential surface of the fixed bar 530 , and the cross-section of the fixed bar 530 may be circular.

When the first speed sensor 510 and the second speed sensor 520 are mounted and fixed on the outer circumferential surface of the fixed rod unit 530 having a circular cross section, the magnetic flux coming out of the protrusion or the magnetic pole tooth of the rotating unit is the first speed sensor 510 . ) and the second speed sensor 520 can be effectively focused to measure a precise magnetic flux change, so that a more accurate rotational speed can be measured. On the other hand, for example, if the speed sensor is mounted on one plane of the fixed bar in the shape of a square column, only a part of the magnetic flux from the protrusion of the rotating part or the magnetic pole tooth is input to the speed sensor, and it may not be possible to measure the precise magnetic flux change. have.

The first speed sensor 510 and the second speed sensor 520 may be provided to be spaced apart from each other. Since the first speed sensor 510 and the second speed sensor 520 can measure about three times the diameter of the probe in the lateral (or height direction) measuring range, it is more sensitive to the change in height of the rotating part 200 in a wide range. In order to respond effectively, the first speed sensor 510 and the second speed sensor 520 may be spaced apart from each other. When the first speed sensor 510 and the second speed sensor 520 are arranged adjacent to each other without being spaced apart from each other, the lateral direction (or height direction) of the first speed sensor 510 and the second speed sensor 520 is measured. Since the ranges overlap each other, the measurement range in the lateral direction (or the height direction) of the speed sensor unit 500 may not sufficiently respond to the change in height of the rotation unit 200 .

On the other hand, the separation distance between the first speed sensor 510 and the second speed sensor 520 may be less than twice the thickness of the outer end of the plurality of protrusions 240 provided along the outer peripheral surface of the upper end or lower end of the rotation unit 200 . The first speed sensor 510 and the second speed sensor 520 face the outer end surfaces of the plurality of protrusions 240 , and the separation distance between the first speed sensor 510 and the second speed sensor 520 is When it is greater than twice the thickness of the outer end, the lateral (or height direction) measuring ranges of the first speed sensor 510 and the second speed sensor 520 are too wide apart from each other, so that the first speed sensor 510 and Any one of the second speed sensors 520 may not face the protrusion 240 of the rotating part. In this case, it is impossible to properly measure the magnetic flux vector value from the protrusion (pole tooth or pole tooth) of the rotating part, so a speed hunting phenomenon may appear similar to measuring with only one speed sensor.

On the other hand, the fixing part 300 is connected to any one of the first to second magnetic core plates 310 and 320, the cover part 380 made of a non-magnetic material; a driving core part 350 connected to the cover part 380 to be spaced apart from the first and second magnetic core plates 310 and 320 and made of a ferromagnetic material; a plurality of driving coil units 360 wound around a portion of the driving core unit 350 to provide rotational driving force to the rotating unit 200 ; and a holder part 370 connected to the cover part 380 to fix the speed sensor part 500 to the upper part.

The cover part 380 is connected to any one of the first to second magnetic core plates 310 and 320 , and is made of a non-magnetic material and is structurally connected to any one of the first to second magnetic core plates 310 and 320 . supported but magnetically detachable.

The driving core part 350 is spaced apart from the first to second magnetic core plates 310 and 320 and is connected to and supported by the cover part 380 made of a non-magnetic material. A method for generating a rotational driving force separately from a magnetic circuit (or magnetic path) formed between the first and second flange portions 220 and 230 and the first and second magnetic core plates 310 and 320 of the fixing portion 300 . A magnetic circuit can be formed.

The plurality of driving coil units 360 may be wound around a portion (eg, protrusion) of the driving core unit 350 to provide rotational driving force to the rotating unit 200 . The plurality of driving coil units 360 is a polyphase winding in which a plurality of end windings are arranged at equal intervals along the inner surface of the driving core unit 350 , and generates magnetic flux by sequentially input driving current to rotate the rotating unit 120 . Alternatively, by interacting with the magnetic field of the plurality of magnetic pole teeth provided on the outer circumferential surface, a torque centered on the rotating shaft is generated to generate a rotational driving force for rotating the rotating unit 120 .

The holder unit 370 is connected to the cover unit 380 to fix the speed sensor unit 500 at the upper end (ie, the upper end of the fixed bar unit 530 ) so that it can be structurally stabilized, and the speed sensor unit 500 . may be made of a non-magnetic material so as to configure a separate magnetic circuit.

The magnetic levitation rotating apparatus of the present invention uses the average value of the rotational speed obtained by summing the rotational speeds of the rotating unit 200 measured by the first speed sensor 510 to the second speed sensor 520, respectively, to rotate the rotating unit. It may further include a control unit (not shown) for controlling the speed. The control unit determines the average value of the rotational speeds measured by the first speed sensor 510 to the second speed sensor 520 as the rotational speed of the rotating unit, and inputs a driving current to the driving coil unit 360 according to the determined rotational speed. By controlling to do so, it is possible to enable stable rotation of the rotating unit 200 regardless of a change in the height of the rotating unit in a vacuum state.

7 is a rotational speed graph of the magnetic levitation rotating device according to an embodiment of the present invention. Referring to FIG. 7 , according to the present invention, even in a vacuum state in which the vacuum space S is maintained in a vacuum, the rotating unit 200 starts to rotate in a stationary state, and in a normal state after a predetermined time elapses, the rotation of the rotating unit 200 according to time As the rotation speed measurement value shows a constant rotation speed waveform, the speed hunting phenomenon is effectively suppressed, and it can be confirmed that the rotating part rotates stably.

8 is a conceptual diagram of a vacuum processing apparatus according to another embodiment of the present invention.

In describing the vacuum processing apparatus according to another embodiment of the present invention, matters overlapping with those described above in relation to the magnetic levitation rotating apparatus according to an embodiment of the present invention will be omitted.

Referring to Figure 8, the vacuum processing apparatus according to another embodiment of the present invention is a magnetic levitation rotating device according to an embodiment of the present invention; a chamber unit 600 connected to the housing unit 100 to form a vacuum space (V); and an exhaust unit 900 that exhausts the vacuum space (V).

A vacuum processing apparatus according to another embodiment of the present invention is an apparatus for processing a rotating object such as a substrate S in a vacuum state in various ways, such as heat treatment or forming a thin film on the substrate. For example, the vacuum processing apparatus may be a rapid thermal process (RTP) that generates high-temperature heat to rapidly heat-treat the substrate S. The substrate S, which is the object to be processed, may be a silicon wafer used in a semiconductor device, or may be glass applied to various objects that require heat treatment, for example, display devices such as LCD and OLED.

The chamber part 600 is connected to the housing part 100 of the magnetic levitation rotating device according to an embodiment of the present invention and is separated from the external space to form a vacuum space (V) in which the vacuum processing for the object to be processed is performed. have. The chamber unit 600 may be formed in a box shape, and an entrance through which an object to be processed may enter and exit may be provided at one side of the chamber unit 600 . Accordingly, heat treatment can be performed by putting the substrate S as a target object into the vacuum space V through the entrance, and the substrate S on which the vacuum processing is completed in the vacuum space is transported to the outside of the chamber 600 through the entrance. can If necessary, a gas supply unit (not shown) for supplying the process gas to the vacuum space V, or a plasma generator (not shown) for activating the process gas may be connected.

The exhaust unit 900 may be connected to the chamber unit 600 or the housing unit 100 to exhaust the vacuum space (V). The exhaust unit 900 may be a vacuum pump, and may exhaust not only air in the vacuum space but also process gases and process by-products required during vacuum processing. When the exhaust unit 900 exhausts the vacuum space and becomes a vacuum state, the outer wall 130 , which is the weakest couple of the housing unit 100 , is crushed inward, and the height of the bottom surface 110 may be increased.

A vacuum processing apparatus according to another embodiment of the present invention includes: a substrate support unit 700 that supports a substrate provided in the vacuum space V, and is connected to the rotation unit to be rotatably provided in conjunction with the rotation unit; a heat source unit 810 provided on the first surface side of the substrate to provide thermal energy toward the substrate; and a temperature measuring unit 830 provided on the second surface side of the substrate to measure the temperature of the substrate.

Various functional parts 800 may be further included according to the vacuum processing process performed in the vacuum processing apparatus.

The substrate support part 700 is installed to support the substrate S in the vacuum space V. The substrate support unit 700 may be formed in a hollow shape with an open central portion to support an edge or an edge of the lower portion of the substrate S. Accordingly, an edge portion of the lower surface of the substrate S may be in contact with the substrate support 700 , and the remaining portion may be exposed downward.

And, the substrate support 700 is connected to the rotating unit 200 of the magnetic levitation rotating device in order to uniform the temperature and the vacuum processing process of the substrate may be provided so as to be rotatable in association with the rotating unit (200).

The heat source unit 810 serves to supply thermal energy to the substrate S, and may include a plurality of light sources 811 irradiating light toward the first surface of the substrate. The heat source unit 810 is disposed to be spaced apart from the upper side of the substrate support unit 700 , and light energy generated by a plurality of light sources 811 such as lamps or semiconductor laser modules provided in the heat source unit 810 is transmitted to the substrate support unit 700 . ) may be provided through the first surface of the substrate S seated on the substrate S to heat the substrate S.

The temperature measuring unit 830 may be provided on the second surface side of the substrate to measure the temperature of the substrate. For example, the temperature measuring unit 830 may be a pyrometer, and one or more are provided below the substrate to detect light incident from the substrate S to measure the temperature. The pyrometer may receive radiant light incident from the substrate and measure radiant energy or light quantity of the radiated light. At this time, the pyrometer is disposed on the lower side of the substrate S seated on the substrate support part 700 to obtain radiant energy and reflectance in the area facing each other, and the substrate S at the position corresponding to each pyrometer. ) can measure the temperature by area or location.

The housing part 100 may further include a base plate 140 connected to an upper portion of the inner wall 120 . The base plate 140 is provided on the second surface side of the substrate, and a lift pin that elevates and descends by supporting the substrate and a temperature measurement unit 830 capable of measuring the temperature of the substrate may be inserted into a through hole, A gas flow passage through which the purge gas may flow may be formed. A reflector that reflects light may be stacked on the base plate.

In addition, a window 820 may be further included between the heat source 810 and the vacuum space V. The window unit 820 may transmit light emitted from the light source 811 so that light energy generated from the light source 811 may be provided to the substrate S.

According to the magnetic levitation rotating device and the vacuum processing device according to an embodiment of the present invention, it is possible to accurately measure the rotational speed of the rotating part even in a vacuum state, and stably controlling the magnetically levitated rotational speed of the rotating part using the accurately measured rotational speed Since it is possible to perform a stable rotation of the rotating unit 200 , it is possible to effectively suppress the occurrence of a speed hunting phenomenon or a speed ripple phenomenon, and a stop of the rotating unit 200 may be possible.

And, the rotation speed can be measured stably regardless of atmospheric pressure and vacuum, so that the rotation speed can be easily controlled regardless of the pressure in the vacuum space.

In addition, the load applied to the electromagnet (position control coil and driving coil) used to effectively suppress vibration and noise that may be generated during unstable rotation of the rotating unit 200, and to move the position of the rotating unit 200 and generate rotational driving force By properly managing the rotational speed of the rotating unit 200 can be controlled stably.

On the other hand, in the case of an object to be rotated or an object to be processed (eg, a semiconductor wafer) that is connected to the rotating unit 200 and rotates together, the rotational speed of the rotating unit 200 causes unstable rotation due to a hunting phenomenon in the radial direction that may occur. It is possible to effectively suppress problems such as a sliding phenomenon or a slip phenomenon in the direction of rotation.

The meaning of "on" used in the above description includes cases of direct contact and cases of not directly contacting but located opposite to the upper or lower surfaces, and partially as well as facing the entire upper or lower surfaces. It is also possible to be positioned to face each other, and it is used to mean that they face away from each other or directly contact the upper surface or the lower surface.

Although preferred embodiments of the present invention have been illustrated and described above, the present invention is not limited to the above-described embodiments, and common knowledge in the field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims It will be understood by those having the above that various modifications and equivalent other embodiments are possible therefrom. Accordingly, the technical protection scope of the present invention should be defined by the following claims.

100: housing part 110: bottom part
120: inner wall 130: outer wall
140; Base plate 200: rotating part
210: outer circumferential surface 220: first flange portion
230: second flange portion 240: protrusion
300: fixing part 310: first magnetic core plate
320: second magnetic core plate 330: second permanent magnet unit
341: horizontal position control coil 342: tilt control coil
343: vertical position control coil 350: drive core part
360: drive coil 370: holder portion
380: cover part 400: displacement sensor part
410: horizontal displacement sensor unit 420: vertical displacement sensor unit
500: speed sensor unit 510: first speed sensor unit
520: second speed sensor unit 530: fixed bar unit
540: first permanent magnet unit 600: chamber unit
700: substrate support 810: heat source
811: light source 820: window portion
830: temperature measurement unit 900: exhaust unit

Claims (13)

a housing unit connected to the chamber unit to form a vacuum space;
a cylindrical rotating part accommodated in the inner space of the housing part and levitating by magnetic force to rotate about a rotating shaft;
a fixing part provided on the outside of the housing part to provide a magnetic force to the rotating part;
a horizontal displacement sensor for measuring the horizontal displacement of the rotating part;
a vertical displacement sensor unit mounted on a bottom surface of the housing unit to measure a vertical displacement of the rotating unit; and
A speed sensor unit provided on the outside of the housing unit to measure the rotation speed of the rotating unit;
The speed sensor unit,
a first speed sensor and a second speed sensor provided at different heights;
a fixing bar part for fixing the first speed sensor and the second speed sensor, and made of a ferromagnetic material; and
A magnetic levitation rotating device comprising a; a first permanent magnet part on which the fixed bar part is supported. The method according to claim 1,
The housing portion includes a cylindrical inner wall connected to each other with the bottom portion interposed therebetween; and a cylindrical outer wall provided on the outside of the inner wall.
The rotating part is accommodated between the inner wall and the outer wall of the housing part,
The thickness of the outer wall is thinner than the thickness of the inner wall and the thickness of the bottom portion of the magnetic levitation rotary device. The method according to claim 1,
The first speed sensor and the second speed sensor is a magnetic levitation rotating device arranged side by side in the vertical direction. The method according to claim 1,
The first speed sensor and the second speed sensor is a hall sensor magnetic levitation rotating device. delete The method according to claim 1,
The first speed sensor and the second speed sensor are mounted and fixed to the outer circumferential surface of the fixing bar,
The cross-section of the fixed bar is a circular magnetic levitation rotating device. The method according to claim 1,
The first speed sensor and the second speed sensor is a magnetic levitation rotating device that is provided to be spaced apart from each other. 8. The method of claim 7,
The rotating part includes a plurality of protrusions provided along the outer peripheral surface of the upper end or lower end,
The separation distance between the first speed sensor and the second speed sensor is a magnetic levitation rotary device that is less than twice the thickness of the outer end of the plurality of protrusions. The method according to claim 1,
The rotating portion extends outwardly from the outer circumferential surface and includes first to second flange portions provided to be spaced apart from each other;
The fixing part,
first and second magnetic core plates spaced apart from each other to face the first and second flange portions;
a second permanent magnet part provided between the first bet and the second magnetic core plate to generate an attraction force to the rotating part; and
A position control coil wound around a portion of the first and second magnetic core plates to control the position of the rotating part by adjusting the suction force according to the direction and magnitude of the current generating magnetic flux;
The speed sensor unit is a magnetic levitation rotating device supported on any one plane of the first to second magnetic core plate. 10. The method of claim 9,
The fixing part,
a cover part connected to any one of the first to second magnetic core plates and made of a non-magnetic material;
a driving core part connected to the cover part so as to be spaced apart from the first to second magnetic core plates and made of a ferromagnetic material;
a plurality of driving coil units wound around a portion of the driving core unit to provide rotational driving force to the rotating unit; and
Magnetic levitation rotating device further comprising; a holder part connected to the cover part for fixing the upper end of the speed sensor part. The method according to claim 1,
Magnetic levitation rotating device further comprising a; a control unit for controlling the rotation speed of the rotation unit using the average value of the rotation speed of the rotation unit measured by each of the first speed sensor to the second speed sensor. Claims 1 to 4, and any one of claims 6 to 11 of the magnetic levitation rotation device;
a chamber part connected to the housing part to form a vacuum space; and
and an exhaust unit for evacuating the vacuum space. 13. The method of claim 12,
a substrate support provided to support the substrate provided in the vacuum space, and to be rotatably connected to the rotating unit and interlocked;
a heat source provided on the first surface side of the substrate to provide thermal energy toward the substrate; and
and a temperature measuring unit provided on the second surface side of the substrate to measure the temperature of the substrate.

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