阅读说明：本技术 一种调整耦合线圈位置实现引出粒子密度调节的装置 (Device for adjusting position of coupling coil to realize leading-out particle density adjustment ) 是由 梁立振 刘伟 时超 李超 王昊明 屈浩 刘洋 于 2021-06-16 设计创作，主要内容包括：本发明公开一种调整耦合线圈位置实现引出粒子密度调节的装置,包含放电腔体、上过渡法兰、下过渡法兰、耦合线圈、绝缘部件、线圈支架、步进电机及齿轮组、滑轨、柔性电缆、射频功率源和和阻抗匹配网络。耦合线圈与放电腔体相对位置不固定,耦合线圈通过绝缘部件连接线圈支架,线圈支架同时容纳步进电机及齿轮组的安装位置,通过控制步进电机在滑轨上的运动来调节耦合线圈在放电腔体的轴向上进行运动,调整下过渡法兰附近的等离子体密度,实现引出粒子密度调节。耦合线圈与阻抗匹配网络之间通过柔性电缆连接。本发明降低了对射频功率源调整响应的要求,降低阻抗匹配网络所需要的调节范围,增强射频等离子体放电的稳定性,降低系统操作的复杂程度。(The invention discloses a device for adjusting the position of a coupling coil to realize the adjustment of the density of outgoing particles, which comprises a discharge cavity, an upper transition flange, a lower transition flange, the coupling coil, an insulating part, a coil bracket, a stepping motor, a gear set, a slide rail, a flexible cable, a radio frequency power source and an impedance matching network. The relative position of the coupling coil and the discharge cavity is not fixed, the coupling coil is connected with the coil support through the insulating part, the coil support simultaneously accommodates the installation positions of the stepping motor and the gear set, the coupling coil is adjusted to move in the axial direction of the discharge cavity by controlling the movement of the stepping motor on the sliding rail, the plasma density near the lower transition flange is adjusted, and the adjustment of the density of the led-out particles is realized. The coupling coil is connected with the impedance matching network through a flexible cable. The invention reduces the requirement on the adjustment response of the radio frequency power source, reduces the adjustment range required by the impedance matching network, enhances the discharge stability of the radio frequency plasma and reduces the complexity of the system operation.)

1. A device for adjusting the position of a coupling coil to realize the adjustment of the density of outgoing particles is characterized by comprising a discharge cavity (1), an upper transition flange (2), a lower transition flange (3), a coupling coil (4), an insulating part (5), a coil bracket (6), a stepping motor, a gear set (7), a slide rail (8), a flexible cable (9), a radio frequency power source and an impedance matching network; the plasma is mainly generated in the discharge cavity (1), the upper transition flange (2) and the lower transition flange (3) are tightly contacted with the discharge cavity (1), and the interior of the discharge cavity (1) is isolated from the external air; the coupling coil (4) is tightly connected with the insulating part (5); the insulating part (5) is tightly connected with the coil bracket (6); the coil support (6) simultaneously contains the stepping motor and the gear set (7), and the stepping motor is controlled to drive the gear set to drive the coil support (6) to move on the sliding rail (8), so that the coupling coil (4) is controlled to move in the axial direction of the discharge cavity (1) relative to the discharge cavity (1), and the plasma density near the lower transition flange (3) is changed; the position adjustment of the discharge cavity (1) needs remote control to ensure the safety of operation; the coupling coil (4) is connected with the impedance matching network by adopting a flexible cable (9); the radio frequency power source and the impedance matching network are in a matching use relationship and are connected through a cable.

2. The device according to claim 1, wherein the isolation of the interior of the discharge cavity (1) from the outside air comprises that a gap is reserved between the coupling coil and the discharge cavity, the slide rail (8) is arranged in parallel with the axis of the discharge cavity (1), and the coupling coil (4) cannot force the discharge cavity (1) to displace in the movement process, so that the tightness of the discharge cavity is ensured.

3. The device according to claim 1, characterized in that said tight connection comprises the use of rigid materials for the coil support (6) and the insulating element (5) to ensure the effectiveness and real-time performance of the stepper motor drive.

4. The device according to claim 1, wherein the moving on the slide rail (8) comprises mounting the stepping motor on a coil support (6), mounting the slide rail (8) on the coil support (6), or fixing the stepping motor on another object, replacing the slide rail (8) and the stepping motor with a combination of a screw and a motor, on which the coil support moves.

5. The device according to claim 1, wherein the movement of the coupling coil (4) relative to the discharge chamber (1) in the axial direction of the discharge chamber (1) comprises using the coupling coil (4) in connection with an impedance matching network using a flexible cable (9), or other deformable mechanical structure to ensure the proper transmission of the rf power during the movement of the coupling coil (4).

6. The apparatus of claim 1, wherein the remote control comprises a signal for controlling the stepper motor transmitted to the stepper motor via an optical fiber to prevent interference of the rf electromagnetic field.

Technical Field

The invention relates to a device for adjusting the position of a coupling coil to realize the adjustment of the density of extracted particles, belonging to the technical field of plasma extraction.

Background

The inductive coupling radio frequency ion source has wide application in the fields of material science, medical instruments, magnetic confinement nuclear fusion and the like. In a Neutral Beam Injection (NBI) system, rf power generates an electromagnetic field through a coupling coil, accelerating electrons to collide with other particles, causing the gas to ionize and form a plasma. Charged particles in the plasma, such as negatively charged electrons and negative ions and positively charged positive ions, can be accelerated and extracted through the extraction electrode, the extracted particles form a particle beam through the acceleration of the acceleration electrode, the particle beam can be used for plasma heating and current driving of a magnetic confinement nuclear fusion device, and the same principle is also used on equipment such as a proton therapeutic apparatus. The coupling coil and the discharge cavity of the current radio frequency ion source are relatively fixed, and the density of the extracted particles is changed by changing the radio frequency power, so that the purpose of changing the beam energy is achieved.

The main disadvantages of this structure are:

(1) the coupling coil and the discharge cavity are relatively fixed, and the position adjusting capability is not available, so that the flexibility is lacked;

(2) the density of the extracted particles is changed only by changing radio frequency discharge parameters (radio frequency power or discharge pressure) or extraction voltage, and frequent change of the discharge parameters or the extraction voltage is not beneficial to stable operation of the system;

(3) the change of radio frequency discharge parameters and the adjustment of the density of the led-out particles can cause the change of equivalent impedance of the coupling coil, thus leading to higher design difficulty and higher cost of the impedance matching network;

(4) the radio frequency power source is required to have a wider power regulation range and response speed;

(5) adjusting the density of the extracted particles by adjusting the discharge parameters or the extraction voltage increases the complexity of the fabrication of the apparatus, requires operators to have rich rf plasma discharge and extraction experience and a solid rf plasma physics foundation, and reduces the universality of the apparatus operation.

Disclosure of Invention

The invention aims to provide a device for adjusting the position of a coupling coil to realize the adjustment of the density of extracted particles, which is used for solving the problem that the density of the extracted particles on the existing equipment is inconvenient to adjust and adjusting the position of a central area of inductive coupling radio frequency plasma discharge relative to an extraction electrode so as to realize the adjustment of the density of the extracted particles; the adjustment of radio frequency power and discharge air pressure in the discharge process of the inductive coupling radio frequency plasma can be reduced, and stable discharge is more favorably realized; the requirement on the power regulation response of the radio frequency power source is reduced, the complexity of the system is reduced, and the reliability is improved; the requirements of the adjustment frequency and the adjustment range of the matching network are reduced, and the stability and the operability of the system are improved.

The technical scheme adopted by the invention for solving the technical problems is as follows:

a device for adjusting the position of a coupling coil to realize the adjustment of the density of outgoing particles comprises a discharge cavity 1, an upper transition flange 2, a lower transition flange 3, a coupling coil 4, an insulating part 5, a coil bracket 6, a stepping motor and gear set 7, a slide rail 8, a flexible cable 9, a radio frequency power source and an impedance matching network; plasma is mainly generated in the discharge cavity 1, the upper transition flange 2 and the lower transition flange 3 are in close contact with the discharge cavity 1, and the interior of the discharge cavity 1 is isolated from the outside air; the coupling coil 4 is tightly connected with the insulating part 5; the insulating part 5 is tightly connected with the coil bracket 6; the coil support 6 simultaneously contains a stepping motor and a gear set 7, and the stepping motor is controlled to drive the gear set and then drive the coil support 6 to move on a sliding rail 8, so that the coupling coil 4 is controlled to move in the axial direction of the discharge cavity 1 relative to the discharge cavity 1, and the plasma density near the lower transition flange 3 is changed; the position adjustment of the discharge chamber 1 requires remote control to ensure the safety of operation. The coupling coil 4 is connected with the impedance matching network by a flexible cable 9. The radio frequency power source and the impedance matching network are in a matching use relationship and are connected through a cable.

Further, the inside of the discharge cavity 1 is isolated from the outside air, a gap is reserved between the coupling coil and the discharge cavity, the sliding rails 8 are arranged in parallel with the axis of the discharge cavity 1, the discharge cavity 1 cannot be forced to displace in the movement process of the coupling coil 4, and the sealing performance of the discharge cavity is guaranteed.

Furthermore, the tight connection comprises that the coil support 6 and the insulating part 5 are made of rigid materials, so that the effectiveness and the real-time performance of the driving of the stepping motor are ensured.

Further, the moving on the slide rail 8 includes that the stepping motor is installed on the coil support 6, the slide rail 8 is installed on the coil support 6, or the stepping motor is fixed on other objects, the slide rail 8 and the stepping motor are replaced by a combination of a screw and a motor, and the coil support moves on the screw.

Further, the movement of the coupling coil 4 in the axial direction of the discharge cavity 1 relative to the discharge cavity 1 includes using the coupling coil 4 to connect with an impedance matching network by using a flexible cable 9, or using other deformable mechanical structures to ensure the normal transmission of the radio frequency power during the movement of the coupling coil 4.

Furthermore, the remote control comprises that the signal for controlling the stepping motor is transmitted to the stepping motor through an optical fiber to prevent the interference of the radio frequency electromagnetic field.

Specifically, the device for adjusting the position of the coupling coil to realize the adjustment of the density of the extracted particles comprises a discharge cavity 1, an upper transition flange 2, a lower transition flange 3, a coupling coil 4, an insulating part 5, a coil support 6, a stepping motor and gear set 7, a sliding rail 8, a flexible cable 9, a radio frequency power source and an impedance matching network. Plasma is generated in the discharge cavity 1, the upper transition flange 2 is an instrument control and air inlet interface, the lower transition flange 3 is a particle leading-out interface, the coupling coil 4 is fixed with the stepping motor through the coil support 6, the stepping motor is connected with the sliding rail through the gear set, the relative position between the coupling coil 4 and the discharge cavity 1 is controlled by controlling the position of the stepping motor on the sliding rail through the remote control system, so that the plasma density near the lower transition flange 3 is adjusted, the coupling coil 4 is connected with the coil support 6 through the insulating part 5, and the radio frequency power is connected with the coupling coil 4 through the flexible cable 9.

The invention has the beneficial effects that: can be through the position of remote control coupling coil relative discharge cavity of remote control system, and then realize drawing out the regulation of particle density, it no longer needs to adjust radio frequency power or discharge pressure to adjust in-process of drawing out the particle density, perhaps can reduce the required control range of radio frequency power and discharge pressure, the impact that above-mentioned parameter adjustment probably caused impedance matching network and radio frequency power source has been avoided, the requirement to the adjustment response of radio frequency power source has been reduced, the required control range of impedance matching network has been reduced, can reduce cost to a certain extent, strengthen the stability that radio frequency plasma discharges, the complexity of the reduction system operation of very big degree.

Drawings

FIG. 1 is a schematic diagram of an inductively coupled RF ion source with adjustable coil position.

In the figure, 1-a discharge cavity, 2-an upper transition flange, 3-a lower transition flange, 4-a coupling coil, 5-an insulating part, 6-a coil support, 7-a stepping motor and a gear set, 8-a slide rail and 9-a flexible cable.

Detailed Description

The invention is described in detail below with reference to the figures and the embodiments. The following examples are only for explaining the present invention, the scope of the present invention shall include the full contents of the claims, and the full contents of the claims of the present invention can be fully realized by those skilled in the art through the following examples.

FIG. 1 is a schematic diagram of an inductively coupled RF ion source with adjustable coil position. As shown in fig. 1, the coil position adjustable inductively coupled rf ion source includes a discharge cavity 1, an upper transition flange 2, a lower transition flange 3, a coupling coil 4, an insulating member 5, a coil support 6, a stepping motor and gear set 7, a slide rail 8, a flexible cable 9, an rf power source, an impedance matching network, and the like. Plasma is mainly generated in the discharge chamber 1. The upper end of the discharge cavity 1 is provided with an upper transition flange 2, the lower end of the discharge cavity is provided with a lower transition flange 3, the upper transition flange 2 and the lower transition flange 3 are in close contact with the discharge cavity 1, and the interior of the discharge cavity 1 is isolated from the outside air. The upper transition flange 2 is an instrument control and air inlet interface, and the lower transition flange 3 is a particle leading-out interface. The coupling coil 4 has a plurality of turns and is wound on the outer wall of the discharge cavity 1. One end of the coupling coil 4 is tightly connected to one insulating member 5, and the other end of the coupling coil 4 is tightly connected to the other insulating member 5. Each insulating member 5 is tightly connected to the coil support 6. The coupling coil 4 is connected with the impedance matching network by a flexible cable 9. Coupling coil 4 is together fixed with step motor through coil brace 6, and step motor is connected with slide rail 8 through the gear train, and step motor and gear train 7 are held simultaneously to coil brace 6, and control step motor drives the gear train and drives coil brace 6 again and move on slide rail 8 to control coupling coil 4 and discharge cavity 1 relatively and discharge the axial of cavity 1 and move, change the near plasma density of transition flange 3 down. The position adjustment of the discharge chamber 1 requires remote control to ensure the safety of operation. The radio frequency power source and the impedance matching network are in a matching use relationship and are connected through a cable.

A certain gap is reserved between the coupling coil 4 and the discharge cavity 1, the sliding rails 8 are arranged in parallel with the axis of the discharge cavity 1, the discharge cavity 1 cannot be forced to displace in the movement process of the coupling coil 4, and the sealing performance of the discharge cavity is guaranteed.

The coil support 6 and the insulating part 5 are made of rigid materials, so that the effectiveness and the real-time performance of the driving of the stepping motor are guaranteed.

The movement on the slide rail 8 includes, but is not limited to, mounting the stepping motor on the coil support 6, and mounting the slide rail 8 on the coil support 6. Or the stepping motor is fixed on other objects, the slide rail 8 and the stepping motor are replaced by the combination of the screw rod and the motor, and the coil support 6 moves on the screw rod.

The coupling coil 4 moves in the axial direction of the discharge cavity 1 relative to the discharge cavity 1, including but not limited to using the coupling coil 4 to connect with an impedance matching network by adopting a flexible cable, or using other deformable mechanical structures to ensure the normal transmission of radio frequency power in the movement process of the coupling coil.

The remote control comprises the step motor is controlled to transmit signals to the step motor through optical fibers, and interference of radio frequency electromagnetic fields is prevented.

In fig. 1, a discharge cavity 1 is a main region for rf plasma discharge, and plasma is mainly concentrated at a position where the geometric centers of the discharge cavity and the coupling coil coincide. The upper transition flange 2 and the lower transition flange 3 are outlets from which particles are led out. The coupling coil 4 and the discharge cavity 11 are not fixed. And the insulating part 5 plays a role in rigidly connecting the coupling coil 4 and the coil support 6, and prevents the radio-frequency power on the coupling coil 4 from influencing the stepping motor and the control system. And the coil bracket 6 plays a role in fixing the position of the coil and accommodating the stepping motor and the gear set 7. A stepping motor and a gear set 7 for providing power for adjusting the position of the coupling coil. A slide 8, usually fixed to the frame of the experimental device, on which slide 8 the movement of the gear allows to adjust the position of the coil 4. The flexible cable 9 is connected with the impedance matching network and the coupling coil, and provides an activity space for the coupling coil 4 on the premise of ensuring that the radio frequency power transmission is not influenced.

The principle and the using method of the device are as follows: in the process of discharging and leading out the inductively coupled radio frequency plasma, the density of the plasma near the lower transition flange 3 has a decisive influence on the density of the led-out particles, the density of the plasma near the lower transition flange 3 is in negative correlation with the distance between the coupling coil 4 and the lower transition flange 3, when the density of the led-out particles needs to be adjusted, the rotation of the stepping motor is controlled through a remote control system, the stepping motor drives the gear set to move on the slide rail 8, so that the coupling coil 4 is driven to move in the direction shown by an arrow (the axial direction of the discharge cavity 1), and the density of the led-out particles is adjusted.

The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and the preferred embodiments are not exhaustive and do not limit the invention to the precise embodiments described. Various modifications and improvements of the technical solution of the present invention may be made by those skilled in the art without departing from the spirit of the present invention, and the technical solution of the present invention is to be covered by the protection scope defined by the claims.