CN202628990U

CN202628990U - Magnetic coupling vacuum transmission device applicable to plasma process equipment

Info

Publication number: CN202628990U
Application number: CN 201220134661
Authority: CN
Inventors: 季安; 赖守亮
Original assignee: Beijing Punasen Electronic Science And Technology Co Ltd
Current assignee: Beijing Punasen Electronic Science And Technology Co Ltd
Priority date: 2012-03-31
Filing date: 2012-03-31
Publication date: 2012-12-26
Anticipated expiration: 2022-03-31

Abstract

The utility model provides a magnetic coupling vacuum transmission device applicable to plasma process equipment. The magnetic coupling vacuum transmission device comprises a driving device, a bearing device and paired permanent magnet group pairs, wherein the driving device is arranged outside a vacuum chamber of the plasma process equipment; the bearing device for bearing a transmitted object is arranged in the vacuum chamber; a power output shaft of the driving device is connected with a transmission device; one group permanent magnets of the permanent magnet group pairs are arranged on the transmission device; another group of permanent magnets are arranged at the corresponding position of the bearing device; and the paired permanent magnets are correspondingly arranged at intervals through the dividing walls of the vacuum chamber. The magnetic coupling vacuum transmission device has the characteristics of simple structure and convenience and flexibility in use.

Description

Magnetic coupling vacuum transmission device suitable for plasma process equipment

Technical Field

The utility model provides a magnetic coupling vacuum transmission device, in particular to a magnetic coupling vacuum transmission device suitable for plasma process equipment.

Background

Many devices that employ vacuum technology, particularly plasma processing devices, involve mechanical actuation in a vacuum environment.

The transfer of mechanical motion in a vacuum environment is often less simple than in an atmospheric environment, as can be briefly explained with reference to fig. 1. An object 03 (e.g., a silicon crystal substrate) can be placed at the position a under the atmospheric pressure in the vacuum chamber, the chamber 01 is then closed, and the chamber is evacuated from the evacuation port 011 by a vacuum pump, so that the object 03 is completely in a vacuum environment. Under normal conditions, the object 03 can also be placed on some kind of carrier 02, such as a tray, a carrier rack or a box. Then how is the object transferred from position a to position B under vacuum? For simplicity, fig. 1 shows only the horizontal movement of the object 03 in a two-dimensional plane, but in practical applications such movement may also be in other modes, such as movement in the vertical direction, as shown in fig. 2, or even three-dimensional.

It is obviously not feasible to place the whole mechanical transmission device, including the motor, the transmission shaft, the transmission connecting rod and the like, in the vacuum chamber to realize the function of mechanical transmission. Semiconductor microelectronic chips and LED chips are required to be manufactured in an extremely clean environment, i.e., the vacuum chamber is not contaminated with metal particles, inorganic particle dust, or organic vapor. The rotating shaft or the transmission shaft of the motor which reciprocates generally needs to be lubricated. If the lubricating medium is liquid or solid grease, the lubricating grease is easy to volatilize under the vacuum condition, thereby causing serious pollution to the vacuum environment and the surface of the chip; if the lubricating treatment is not carried out, a large amount of solid powdery abradant is easily generated to pollute the vacuum chamber. In addition to this, there are other technical problems.

The conventional solution is to place the actuator partly inside the vacuum chamber and partly outside the vacuum chamber. The power source of the transmission device, namely the motor is arranged outside the vacuum chamber, is directly connected with a transmission shaft or a transmission connecting rod of the motor and is also arranged in the atmospheric pressure environment outside the vacuum chamber. The object to be driven and the link means directly connected to the object are placed in the vacuum chamber. The two sets of link devices placed in the atmospheric environment and the vacuum environment often realize the functions of transmitting the mechanical motion in the atmospheric environment to the vacuum environment and conveying objects in the vacuum chamber in a direct mechanical contact mode.

Fig. 3 schematically illustrates a conventional solution for imparting horizontal motion to a vacuum environment. Generally, the output shaft 041 of the motor or motor 04 is connected through a transmission link 043, the output shaft 041 is connected with some kind of screw transmission device 042 to convert the rotation motion of the motor or motor 04 into the horizontal motion of the transmission link 043, and the transmission link 043 is connected with a movable flange 045 of a vacuum sealing corrugated pipe 046 through a transmission link connector 044, so as to push the vacuum sealing corrugated pipe 046 to make a telescopic motion in the horizontal direction. The object 03 to be driven in the vacuum chamber 01 is placed on the carrier device 02, and is connected to a driving connecting rod 049 disposed in the vacuum chamber 01, and one end of the driving connecting rod 049 in the vacuum chamber 01 is connected to a movable flange 047 on a vacuum bellows 046. Thus, when the driving link 04 outside the vacuum chamber 01 moves horizontally, the driving link 048 inside the vacuum chamber 01 is pushed and drives the driven object 03 to move horizontally. In this way, mechanical movements outside the vacuum are transmitted into the vacuum chamber 01. Here, a flexible vacuum bellows 046 performs the function of vacuum sealing together with an O-ring 048 arranged between the vacuum chamber 01 and the bellows 046. The range of motion of the transmission connecting rod, i.e. the transmission range of the object in the vacuum chamber, is limited by the extension range of the soft vacuum bellows.

Fig. 4 schematically illustrates a conventional solution for transferring a rotational movement to a vacuum environment. Here, the rotational motion of the output shaft 051 of the motor 05 needs to be transferred into the vacuum chamber 01, and one generally uses a magnetic fluid sealing device 052 to complete the vacuum sealing of the transmission shaft 051. The rotation axis of the transmission shaft 051 is fixed, that is, the axis of the object rotating in the vacuum chamber cannot be changed.

The above examples, which represent the most common way of transmitting and controlling the motion to a vacuum environment at present, have the obvious drawbacks: (1) a vacuum seal is required and (2) the range of motion is limited. In general, a sealing member such as a rubber gasket, a vacuum hose, or a magnetic fluid is used as a vacuum sealing device. Not only the mechanical structure of the sealing part is more complicated, the manufacturing cost of the equipment is increased, but also the sealing part is easy to wear and fatigue failure in the using process because the sealing part needs to do reciprocating motion, and the sealing part made of rubber is easy to age and fail, so the long-term stability of the equipment is unreliable, and frequent maintenance is required.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to improve prior art's not enough, provide a carry out the magnetic coupling vacuum transmission who is applicable to plasma process equipment of motion transmission through magnetic coupling.

The purpose of the utility model is realized like this:

a magnetic coupling vacuum transmission device suitable for plasma process equipment comprises a driving device, a bearing device and a pair of permanent magnet pairs, wherein the driving device is arranged outside a vacuum chamber of the plasma process equipment; the paired permanent magnets are disposed to correspond to each other across the partition wall of the vacuum chamber.

One group of permanent magnets can be one or more. The paired permanent magnets are disposed to correspond to each other across the partition wall of the vacuum chamber.

The group of permanent magnets is distributed on a plane.

Furthermore, the end faces of one group of permanent magnets in the permanent magnet group are opposite to the end faces of the other group of permanent magnets, and the group of permanent magnets are distributed on one plane.

The permanent magnets are rare earth series neodymium magnets or samarium cobalt magnets.

A motion guide rail is respectively arranged inside and outside the vacuum chamber, the driving device and/or the transmission device outside the vacuum chamber and the bearing device inside the vacuum chamber are arranged on the corresponding guide rails, and the relative positions of the motion guide rails inside and outside the vacuum chamber are aligned; or,

the driving device is a driving device with the output speed of less than 10 m/min, or the transmission mechanism connected with the driving device is a device with the output speed of less than 10 m/min. If the velocity is too high, the accuracy of the motion may be affected.

Moving rollers or balls or rollers are arranged between the moving guide and the drive and/or transmission and the support device to reduce friction.

The utility model discloses a through the strong magnetic coupling that utilizes two or polylith permanent magnets of component group to right, the permanent magnet in the vacuum chamber outside moves under drive arrangement's drive, and the permanent magnet in the vacuum chamber also moves thereupon, realizes transmitting the mechanical motion of vacuum outside to the vacuum environment then and carry out the purpose controlled.

The vacuum chamber may be made of metal aluminum or aluminum alloy, or ceramic, rigid plastic, or the like, which does not shield the magnetic force of the magnet and significantly attenuates or disperses the magnetic force. The wall thickness and geometry of the vacuum chamber should also meet the requirement that no significant shielding, attenuation or divergence of the magnetic forces occur. For example, in a vacuum chamber made of aluminum or aluminum alloy, the wall thickness of the chamber is preferably in the range of 5-30 mm, and the wall thickness of the chamber should not change in the stroke range of the permanent magnet pair movement. The wall of the cavity is too thin, for example less than 5 mm, and under the condition that the cavity is in vacuum, the cavity is subjected to huge pressure to generate mechanical deformation; if the wall is too thick, for example, more than 30 mm, the magnetic force of the magnet is shielded greatly, so that the coupled magnetic force is reduced significantly. In addition, the chamber wall should maintain a relatively constant distance from the inner and outer pairs of permanent magnets, i.e., the gap between the magnets and the wall should not change significantly as the pairs move. Otherwise, in the process that the permanent magnet pair moves and transmits the movement, the actually coupled magnetic force changes, so that the movement transmission cannot be performed smoothly.

The permanent magnet is a permanent magnet with remanence of 0.5-1.5 Tesla, and can be a rare earth neodymium magnet (Nd)₂Fe₁₄B) And samarium cobalt (SmCo) magnets having remanence in the range of 0.6 to 1.4 Tesla and 0.8 to 1.2 Tesla, respectively.

The permanent magnets are strip-shaped, and when the strip-shaped permanent magnets are arranged, the long axis direction of the strip-shaped permanent magnets is arranged along the movement direction.

The utility model provides a magnetic coupling vacuum transmission suitable for plasma process equipment makes plasma process equipment's transmission structure become very simple through using magnetic coupling vacuum transmission, through the special design of arranging of permanent magnet and the corresponding structure and the selection of material of vacuum chamber, overcome among the prior art magnetic drive for example intermittent type formula vibration be difficult to overcome the defect, open up new road for using this ancient drive mechanism of magnetic drive in the power transmission of plasma process equipment such vacuum environment.

The invention is further illustrated by the following figures and examples.

Drawings

FIG. 1 is a schematic view of a moving substrate horizontally in a vacuum chamber of a plasma processing apparatus.

FIG. 2 is a schematic view of moving a substrate vertically in a vacuum chamber of a plasma processing apparatus.

Fig. 3 is a schematic view of a prior art transfer mechanism for moving a substrate horizontally in a vacuum chamber of a plasma processing apparatus.

Fig. 4 is a schematic view of a prior art transmission mechanism for horizontal rotational movement in a vacuum chamber of a plasma processing apparatus.

Fig. 5 is a schematic diagram of the principle of the magnetic coupling vacuum horizontal movement transmission device suitable for the plasma processing equipment provided by the present invention.

Fig. 6 is a schematic diagram of the principle of the magnetic coupling vacuum vertical movement transmission device suitable for the plasma processing equipment of the present invention.

Fig. 7 is a schematic structural view of a magnetic coupling vacuum vertical movement transmission device suitable for a wafer transfer chamber in plasma processing equipment.

Fig. 8 is a schematic structural diagram of a magnetic coupling mobile transmission device suitable for use in a process chamber of a plasma processing apparatus according to the present invention.

Fig. 9 is a schematic structural view of a magnetic coupling vacuum rotation transmission device suitable for plasma processing equipment according to the present invention.

Detailed Description

The utility model provides a specific embodiment of magnetic coupling vacuum transmission suitable for plasma process equipment is shown in fig. 5, and motor 04 and the transmission connecting rod 043 that connects affiliated screw drive 042 on motor output shaft 041 and be connected with transmission 042 are placed outside vacuum chamber 01 completely, and remaining transmission 02 part is then all placed in vacuum chamber 01, and transmission sets up on a slide rail. The connection, or coupling, of the two sets of actuators is achieved by a pair of permanent magnets, namely a permanent magnet 11 arranged on the actuator linkage 043 and a permanent magnet 12 arranged on the actuator 02. Of course, in practical applications, multiple pairs of permanent magnets may also be used.

The material of the vacuum chamber 01 may be aluminum or aluminum alloy, or may be other materials that do not shield, significantly attenuate, or diffuse the magnetic force of the magnet. Thus, when one permanent magnet, for example, the permanent magnet 11 placed outside the vacuum chamber 01, is actively moved, under the influence of the magnetic force, the other permanent magnet, for example, the permanent magnet 12 placed inside the vacuum chamber 01, passively "follows" the movement, and drives the transmission link 02 connected with the permanent magnet to move, so as to push the conveyed object 03 contacted with the transmission link. Thus, the mechanical movement of the object to be transported from position a to position B in the vacuum chamber is achieved. Fig. 5 illustrates the mechanical motion transfer in two-dimensional horizontal direction.

The movement in the two-dimensional vertical direction can also be realized by means of permanent magnet coupling, as shown in fig. 6, a screw drive 052 is connected to an output shaft 051 of the motor 05 outside the vacuum chamber 01, and a drive connecting rod 053 is connected to the screw drive. The transmission connecting rod 053 is provided with a permanent magnet 22, a bearing device 02 arranged on a slide rail (not shown in the figure) in the vacuum chamber 01 is provided with a permanent magnet 21, the permanent magnet 21 and the permanent magnet 22 form a coupled permanent magnet pair, as shown in fig. 6, the motor 05 rotates, and the object 03 to be moved in the vacuum chamber 01 can vertically move.

Fig. 7 and 8 show an example of a design, which details the construction of the vacuum actuator by means of magnetic coupling. In fig. 7, it can be seen that the vacuum sheet transfer chamber cavity 7h with an open upper part is formed by processing aluminum alloy material and is formed by "hollowing out" a whole piece of ingot aluminum, and all cavity walls have good vacuum sealing performance. A movable cover plate 7m is arranged on the uppermost opening of the cavity, and when the cover plate is opened, a substrate 7j needing to be transmitted can be placed on a mechanical arm 7k which is arranged in the cavity and used for transmitting the substrate; when the cover plate is closed, the vacuum pumping port 7g on the vacuum chamber bottom plate of the sheet conveying chamber can be used for vacuumizing the sheet conveying chamber. Of course, a complete O-shaped rubber sealing ring 7n is required to be arranged at the joint of the movable cover plate and the vertical wall of the sheet transmission chamber so as to realize and ensure high vacuum degree in the sheet transmission vacuum chamber.

In this cross-section as shown in fig. 7, the components can also be seen: two rail holders 7a are provided on the outer lower bottom surface of the vacuum chamber 7h, and a rail 7e is provided on the rail holders 7 a. A stepping motor 7b is arranged on the guide rail 7e, and the stepping motor 7b can horizontally move on the guide rail 7e when being started. The position sensor 7f is mounted on the slide rail 7 e; one of the neodymium permanent magnets 7c is fixedly connected with the stepping motor 7b, and the other one is fixed with a base of a sheet conveying manipulator 7k arranged on a guide rail 7d in the vacuum cavity and corresponds to the permanent magnet fixed on the stepping motor; in order to reduce friction force and increase transmission stability, a movable pulley 7l is arranged between a base of the manipulator and a guide rail 7 d; the passage 7i between the sheet-conveying vacuum chamber and the process chamber corresponds to the moving route of the robot arm 7 k. Not shown in fig. 7 are a cassette which is installed in the transfer chamber and can hold a plurality of substrates, a vacuum pump which is installed on a vacuum port 7g at the bottom of the transfer chamber, a vacuum pressure sensor, a vacuum valve, and the like. The components form a whole and have the function of realizing mechanical motion transmission under the condition that the sheet transmission chamber is in vacuum. When the stepping motor is started, the motor horizontally moves on the guide rail 7e outside the film transmission cavity, and the permanent magnet 7c arranged on the stepping motor also moves along with the motor. Due to the coupling of the magnetic force, the other permanent magnet arranged in the vacuum chamber of the transmission piece moves correspondingly. The magnet in the film transfer cavity is fixed with the lower end of the manipulator arranged in the cavity, so that the permanent magnet effectively drives the manipulator to horizontally move along the guide rail 7d in the film transfer cavity with the assistance of the pulley, and the substrate is conveyed into the process chamber from the film transfer chamber through the channel 7 i.

In the design shown in fig. 7, but not shown in fig. 7, there is another set of transmission means of "stepping motor + permanent magnet pair + guide rail" at the right end of the film-transferring vacuum chamber. The working principle of the device is almost the same as that of the horizontal motion transmission described above, and the principle and structure can refer to fig. 6, which is not described herein again. The two sets of transmission devices can realize complex film transmission functions by mutual matching, such as: taking a certain substrate out of the cassette, transferring the substrate into the process chamber through a passage between the sheet transfer chamber and the process chamber, and placing the substrate on an electrode of the process chamber to be subjected to a plasma process; after the plasma process is completed, the substrate is transferred back into the transfer chamber through the passage between the transfer chamber and the process chamber and replaced in the cassette.

The above example illustrates how mechanical motion transfer in a vacuum environment is achieved in a wafer transfer chamber of a plasma apparatus and between the wafer transfer chamber and a process chamber through magnetic coupling.

Fig. 8 is a cross-sectional view illustrating how mechanical motion transfer in a vacuum environment is achieved by magnetic coupling in a process chamber of a plasma apparatus. The components that can be seen here are: the upper half part 8n and the lower half part 8j of the process cavity are processed by aluminum alloy, and an O-shaped ring 8m for realizing vacuum sealing between the two parts of cavities; a lower electrode 8b fixedly connected with the lower half part 8j of the process cavity in the process cavity and a radio frequency system 8d connected with the lower electrode together; an upper electrode 8q fixedly connected with the upper half part 8n of the process cavity in the process cavity, a radio frequency system 8p connected with the upper electrode together, a gas inlet 8o arranged on the upper half part 8n of the process cavity and a gas spray header 8r arranged on the gas inlet; the robot 8k for transferring substrates in the horizontal direction, which robot is provided with a substrate 8a, has access from the transfer chamber to the process chamber via a channel 8l, the movement of which robot is already described in fig. 7; a lifting thimble 8c for bearing the substrate is arranged below the outer surface of the process cavity, hermetically penetrates through the cavity wall of the process cavity and extends into the process cavity, and the lower end of the lifting thimble 8c positioned outside the process cavity is fixed on a driving connecting rod 8e which moves up and down; one of the neodymium permanent magnet pairs 8f is fixed with a stepping motor 8i, the other is fixed with a driving connecting rod 8e, and a metal plate 8g is arranged between the two permanent magnets to isolate the stepping motor 8i from a radio frequency environment so as to reduce the interference of radio frequency signals to the stepping motor; the stepping motor 8i is mounted on a moving guide 8 h. Not shown in fig. 8 are devices, including a substrate chuck mounted in the process chamber, a vacuum pump mounted at the bottom of the process chamber, a vacuum pressure sensor, and a vacuum valve. The above components, which are integrated, perform the function of transmitting mechanical motion under vacuum in the process chamber. When the stepping motor is started, the motor moves vertically on a guide rail 8h provided with a threaded rod outside the vacuum chamber, and a permanent magnet 8f arranged on the stepping motor moves along with the threaded rod. Due to the coupling of the magnetic force, the other permanent magnet 8f correspondingly moves to drive the driving connecting rod 8e of the lifting thimble 8c to mechanically move upwards in the vertical direction in the vacuum process chamber, so as to receive the substrate 8a from the manipulator 8k and separate the substrate from the manipulator 8 k. After the manipulator retreats from the process chamber, the lifting thimble moves downwards along with the driving connecting rod in the vertical direction, and the substrate is dropped on the surface of the lower electrode.

Can also pass through the utility model provides a device realizes the last rotary motion of two-dimensional direction. As shown in fig. 9, a transmission link 061 is connected to an output shaft of the motor 06 outside the vacuum chamber 01, and a support 062 is provided on the transmission link 061, and the permanent magnet 31 is provided on the support 062 in a plane. In the vacuum chamber 01, a permanent magnet 32 is provided on a carrying device 02 provided on a holder (not shown) through a bearing, corresponding to the permanent magnet 31, so that when the motor 06 rotates, the carrying device 02 in the vacuum chamber 01 rotates. Of course, in such a driving situation, it is more efficient to use a plurality of permanent magnets in pairs.

Two-dimensional compound motion and three-dimensional motion can be realized by two-dimensional horizontal motion, vertical motion and rotary motion. Thus, as long as the two sets of transmission mechanisms inside and outside the vacuum chamber 01 have sufficient space and freedom of mechanical movement, there are many mechanical transmission modes that can be realized, and the degree of freedom of mechanical transmission is large.

In the prior art, magnets are arranged on two sides of a partition wall, so that the motion of one side drives a motion part on the other side to move along with the motion of the motion part under the action of a magnetic field, however, the transmission motion in the prior art is not generally the transmission motion to a vacuum chamber, and electromagnets are often used, but permanent magnets are not used. In addition, in the prior art, a plurality of magnetic force transmission movements are transmission rotation movements, the partition wall is generally cylindrical, and the diameter of a chamber without a power driving device is smaller than the inner bore diameter of the outer magnetic steel. The permanent magnet is used for forming magnetic field transmission motion, so that the structure of the device becomes very simple, and meanwhile, the motion in a spatial multi-dimensional direction can be conveniently realized.

The principle of transmitting mechanical motion by magnetic coupling of permanent magnets is that two magnets, which attract each other, will remain in a certain stable relative position under the action of magnetic lines of force. Thus, when one magnet of the pair of magnets moves and deviates from the relative position, the magnetic force lines push the one magnet or the other magnet to move so as to restore the stable relative position. Therefore, the coupling efficiency of the two permanent magnets and the urine of the coupling force become key indexes for realizing the effective transmission of mechanical motion.

First, theoretically, the coupled magnetic force needs to be large enough, while the permanent magnet should not be too bulky, the magnetic force should not be too attenuated or spread when passing through the vacuum chamber, and so on. In the eighties of the last century, the rare-earth series neodymium magnet (Nd) with super-strong magnetic force was discovered and used in human Utility model₂Fe₁₄B) And samarium cobalt (SmCo) magnets having remanence of 0.6-1.4 Tesla and 0.8-, respectivelyThe level of 1.2 Tesla is about 5-10 times or more that of a conventional iron-nickel magnet, and the remanence is an index for measuring the strength of magnetic force. Today, neodymium magnets, which have strong magnetic forces and are compact, have become common products and are widely available on the market at a relatively modest price.

When a piece of material with a certain thickness is placed between two permanent magnets, magnetic lines of force can pass through the piece of material, and the strength of the magnetic field can be attenuated or dispersed to different degrees. Therefore, for the purpose of effectively transferring the mechanical motion to the vacuum chamber, the material of the vacuum chamber should not be stainless steel series material, such as 304 or 316 series stainless steel material, because the ferrous material will be magnetized by the magnetic force lines, resulting in failure of the magnetic coupling, but can be any material that is not easily magnetized and has good vacuum sealing performance, such as aluminum, aluminum alloy, ceramic, rigid plastic, etc. Today, people generally adopt aluminum or aluminum alloy materials as the cavity materials of plasma processing equipment. In order to reduce the attenuation of the magnetic field, the thickness of the material should not be too thick. The thickness of the cavity wall of the vacuum cavity made of aluminum or aluminum alloy material is in the range of 5-30 mm, and the wall thickness of the cavity cannot be changed remarkably in the stroke range of the movement of the permanent magnet pair group, so that the actually coupled magnetic force is prevented from changing greatly in the stroke range of the magnet.

Second, under certain coupling conditions, the payload to be driven should be matched to the strength of the magnetic force. In other words, if the coupled permanent magnets are weak enough to not push an excessively heavy transmission load, the effectiveness of transmitting motion through the magnetic coupling is reduced. Therefore, in designing and using the transmission described in the present invention, two factors should be considered: (1) the strength of the magnetic force of the permanent magnet needs to be sufficiently large and (2) the payload to be transferred needs to be as small as possible. For example, in the manufacture of semiconductor microelectronic chips, conventional wafer transfer mechanisms (e.g., robots) are designed to reduce weight, the substrates and cassettes have a self-weight of typically 5-10 kg or less, horizontal motion can also reduce friction by using guide rails and pulleys, and vertical motion can also reduce gravitational loading by using bearings as appropriate.

When the magnetic coupling mode is used for motion transmission, the driven device may generate intermittent vibration during the motion process, and the intermittent vibration phenomenon is avoided as much as possible in the application of plasma vacuum transmission. The reasons for this are roughly the following: (1) when the magnet pair moves relative to the metal cavity, induced current is caused on the surface of the cavity, the direction of the induced current is related to the moving direction of the magnet, the induced current conforms to the right-hand rule, the magnitude of the induced current is in direct proportion to the moving speed of the magnet, and the induced current can act with the magnetic field of the magnet to generate electromagnetic damping force to increase the resistance of the magnet to move; (2) the guide rail which is arranged outside the vacuum cavity and used for guiding the motor and the magnet to move and the guide rail which is arranged in the vacuum cavity and used for guiding the magnet to move are not completely correspondingly and parallelly arranged, so that the stable movement of the magnet is prevented; (3) the guide rail for guiding the movement of the magnet has larger friction force to influence the stable movement of the magnet; (4) the coupling magnetic force is weak and is not sufficient to smoothly transmit motion.

The utility model discloses to solve above-mentioned problem that causes intermittent type vibration, made technical processing very much, include: (1) when the strip-shaped permanent magnets are arranged, the long axis direction of the strip-shaped permanent magnets needs to be along the direction of the guide rail so as to reduce the area change rate of shearing of magnetic lines of force and the metal cavity when the magnets move at a certain speed as much as possible, thereby reducing induced current; (2) the horizontal or vertical movement speed of the stepping motor is lower than 10 m/min to reduce induced current; (3) the relative position of the inner and outer motion guide rails of the vacuum chamber ensures alignment in design; (4) a moving pulley is adopted on the guide rail to reduce friction force; (5) depending on the payload and chamber wall thickness, the magnets are chosen to have sufficient remanence to ensure that the magnetic force coupled is sufficient to smoothly transmit motion.

The transmission mode of transmitting mechanical motion from the atmospheric environment to the vacuum environment by utilizing the magnetic force of the permanent magnet has the characteristics of effectiveness, simplicity, convenience, reliability and the like compared with the traditional transmission mode, and has the following specific advantages:

one, realize that the degree of freedom of mechanical transmission is big, the flexibility is strong. The traditional transmission mode is limited by connection and sealing of a vacuum interface and an atmospheric interface, so that the traditional transmission mode has no greater flexibility and degree of freedom; by means of magnetic coupling, as long as the physical space inside and outside the vacuum chamber permits, the mode and degree of freedom of motion are almost unlimited.

And secondly, the degree of automation of mechanical transmission is higher. Realize automatic control simple accurate relatively under atmospheric environment, and the transmission mode that this utility model relates to, its control action can all be accomplished under atmospheric environment, consequently, mechanical transmission can full automation.

Thirdly, the requirements on the transmission mechanism in the aspects of processing, assembly, maintenance and the like are greatly simplified. Compared with the traditional transmission mode, the transmission is carried out in a magnetic coupling mode, so that a mechanical structure on an atmosphere and vacuum interface, in particular a vacuum sealing structure, can be completely omitted. As is well known, the vacuum seal structure is complicated and requires components such as a vacuum seal bellows, an O-ring, and a magnetic fluid seal ring, which increases the manufacturing cost.

Fourthly, transmission is carried out in a magnetic coupling mode, and the service performance and the stability are high. Conventional transmission, and because of the moving parts and seals involved, wear and degradation can occur during use, resulting in reduced reliability of service performance and the need for periodic manual maintenance. And the transmission is carried out by using a magnetic coupling mode, so that the problems of a transmission mechanism can be greatly avoided.

The objects transported in the plasma process are: (1) a substrate or vessel including a silicon crystal substrate, a compound semiconductor substrate, a sapphire substrate, a glass substrate or vessel, a ceramic substrate or vessel, a metal substrate or vessel, etc., on which other materials such as a thin film may be present; single or multiple pieces of substrates or vessels may also be placed on a separate tray for ease of transport as the object of transport; (2) a cassette or similar mechanical structure that carries a plurality of substrates or substrate trays; (3) a vessel box or similar mechanical structure that carries a plurality of vessels or vessel trays; (4) a chuck or similar mechanical structure for holding a substrate or substrate tray; (5) calipers or similar mechanical structures for holding vessels or vessel trays; (4) pins for carrying and lifting substrates or substrate trays, or pins for carrying and lifting vessels or vessel trays, or similar mechanical structures.

The drive and the transmission connected with the drive can be connected with a control device, and the control device of the transmission can comprise manual, semi-automatic or full-automatic mode control.

The vacuum chamber, i.e. the vacuum environment in which the carrier operates, is defined as any environment in which the gas pressure is below 760 mmhg.

In the above examples, we have used names such as "transfer chamber", "process chamber", "channel between transfer chamber and process chamber" to describe the vacuum environment on the plasma apparatus. As is well known to those of skill in the art, other names may be used throughout to describe these vacuum environments on plasma processing equipment. We also use names such as "substrate", "cassette", "robot", "chuck", "lift pins", etc. to describe some of the elements of the actuator. For the same reason, a person with little expertise may use other names to describe those elements. However, no matter what name is used, the technical problem solved by the present invention is how to more effectively realize the transmission of mechanical motion in a vacuum environment. The above examples are merely examples and are not intended to limit the scope of the present invention.

Claims

1. A magnetic coupling vacuum transmission device suitable for plasma process equipment is characterized in that: the plasma processing device comprises a driving device arranged outside a vacuum chamber of plasma processing equipment, a bearing device arranged in the vacuum chamber and used for bearing a driven object, and a pair of permanent magnet pairs, wherein a power output shaft of the driving device is connected with a transmission device, one permanent magnet in the permanent magnet pair is arranged on the transmission device, and the other permanent magnet is arranged at a corresponding position on the bearing device; the paired permanent magnets are disposed to correspond to each other across the partition wall of the vacuum chamber.

2. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 1, wherein: the group of permanent magnets are distributed on one plane; and/or the presence of a gas in the gas,

one group of the permanent magnets is one piece or a plurality of pieces.

3. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 1, wherein: the vacuum chamber can be made of metal aluminum or aluminum alloy, or ceramic or rigid plastic; or,

the thickness of the cavity wall of the vacuum chamber is in the range of 5-30 mm; or,

and in the stroke range of the movement of the permanent magnet pair, the wall thickness of the cavity of the vacuum cavity is equal to the thickness of the wall.

4. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 1, wherein: the permanent magnets are rare earth series neodymium magnets or samarium cobalt magnets.

5. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 1, wherein: the end faces of one group of permanent magnets in the permanent magnet group are opposite to the end faces of the other group of permanent magnets, and the group of permanent magnets are distributed on one plane.

6. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 1, wherein: a motion guide rail is respectively arranged inside and outside the vacuum chamber, the driving device and/or the transmission device outside the vacuum chamber and the bearing device inside the vacuum chamber are arranged on the corresponding guide rails, and the relative positions of the motion guide rails inside and outside the vacuum chamber are aligned; or,

the driving device is a driving device with the output speed of less than 10 m/min, or the transmission mechanism connected with the driving device is a device with the output speed of less than 10 m/min.

7. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as claimed in claim 6, wherein: moving rollers or balls or rollers are arranged between the moving guide and the drive and/or transmission and the support device to reduce friction.

8. The magnetically coupled vacuum actuator suitable for use in a plasma processing apparatus according to any one of claims 1 to 7, wherein: the permanent magnets are strip-shaped, and when the strip-shaped permanent magnets are arranged, the long axis direction of the strip-shaped permanent magnets is arranged along the motion direction; and/or the presence of a gas in the gas,

the permanent magnet is a permanent magnet with the remanence of 0.5-1.5 Tesla.

9. The magnetically-coupled vacuum actuator suitable for use in a plasma processing apparatus as recited in claim 8, wherein: the permanent magnet is a neodymium magnet, and the remanence of the permanent magnet is 0.6-1.4 Tesla; or the permanent magnet is a samarium cobalt magnet, and the remanence of the permanent magnet is 0.8-1.2 Tesla.