Systems and methods for applying symmetric or asymmetric forces to ion source temperature control

Abstract

An ion source in which compressive forces applied to panels on both sides of an extraction aperture can be independently varied. Modifying the compressive force between the panel and the arc chamber may enable temperature control of the ion source by modifying the thermal contact resistance between the two components. This may enable more control of the temperature of the panel, and more particularly, the temperature profile of the entire panel may be controlled due to precise control of the thermal contact gradient along the length of the panel. The ion implantation system includes two adjustable tensioning systems, each of the two adjustable tensioning systems including an actuator. A command signal is provided to each adjustable tensioning system using a controller. In an embodiment, a feedback signal representative of the torque or force experienced by the actuator is generated by each adjustable tensioning system.

Description

[0001] This application claims priority to U.S. Patent Application Serial No. 18 / 143,684, filed May 5, 2023, the disclosure of which is incorporated by reference herein in its entirety. TECHNICAL FIELD

[0002] Embodiments of the present disclosure relate to systems and methods for controlling the temperature of an ion source by applying a force to a faceplate. BACKGROUND

[0003] Fabrication of semiconductor devices involves a number of discrete and complex processes. One such process can utilize an ion beam that can be extracted from an ion source. In the ion source, a feed gas is excited to form ions. The ions are then extracted from the ion source through an extraction aperture disposed on a faceplate. The ions are manipulated downstream through various components including electrodes, acceleration and deceleration stages, and a mass analyzer.

[0004] One such ion source is an indirectly heated cathode ion source. An indirectly heated cathode (IHC) ion source operates by supplying current to a filament disposed behind a cathode. The filament emits hot ionizing electrons that are accelerated toward the cathode by an applied potential, which in turn heats the cathode so that electrons are emitted into an arc chamber of the ion source. The cathode is disposed at one end of the arc chamber. A repeller can be disposed on the end of the arc chamber opposite the cathode. The cathode and repeller can be biased to repel electrons, directing them back toward the center of the arc chamber. In some embodiments, a magnetic field is used to further confine the electrons within the arc chamber. A plurality of sides are used to connect the two ends of the arc chamber.

[0005] An extraction aperture is disposed along one of the sides, referred to as a faceplate. The extraction aperture is positioned near the center of the arc chamber through which ions formed in the arc chamber can be extracted.

[0006] In some cases, material can deposit on the interior surface of the faceplate, which can make the ion beam non-uniform. Such material can form by condensation of the feed gas species on the cooler surface. Alternatively, in some systems, material deposition on the interior surface of the faceplate can preferentially occur on the hotter surface, depending on the feed gas species. The rate of deposition can be related to the temperature of the faceplate. In many IHC ion sources, the side of the faceplate closest to the cathode can be hotter than the side of the faceplate furthest from the cathode due to proximity to the hot radiating cathode. Thus, material deposition can be uneven, making the extracted ion beam non-uniform.

[0007] Accordingly, it would be beneficial to have a system that controls the temperature of the faceplate to reduce material buildup. SUMMARY

[0008] An ion source is disclosed in which the compressive force applied to the faceplate on both sides of the extraction orifice can be independently varied. Modifying the compressive force between the faceplate and the arc chamber can enable temperature control of the ion source by modifying the thermal contact resistance between the two components. This can enable more control of the temperature of the faceplate and more specifically control of the temperature profile across the faceplate by precisely controlling the thermal contact gradient along the faceplate length. An ion implantation system includes two adjustable tensioning systems, each of which includes an actuator. A controller provides a command signal to each adjustable tensioning system. In some embodiments, a feedback signal representative of the torque or force experienced by the actuator is generated by each adjustable tensioning system. This feedback signal can be used to adjust the command signal supplied to each adjustable tensioning system.

[0009] According to one embodiment, an ion implantation system is disclosed. The ion implantation system includes an ion source including an arc chamber including a plurality of chamber walls and having a first end and a second end, and a faceplate having an extraction orifice disposed on a top of the plurality of chamber walls, a source housing in which the arc chamber is disposed, a first clasp and a second clasp for pressing the faceplate against the top of the plurality of chamber walls of the arc chamber, wherein the first clasp is disposed proximate the first end and the second clasp is disposed proximate the second end, and a first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system being in communication with the first clasp to apply a tension force to the first clasp, the second adjustable tensioning system being in communication with the second clasp to apply a tension force to the second clasp, and a controller in communication with the first adjustable tensioning system and the second adjustable tensioning system configured to apply a different tension force to each of the first clasp and the second clasp. In some embodiments, the tension force applied proximate the first end of the cathode in the arc chamber is greater than the tension force applied to the second end to increase the temperature of the faceplate. In some embodiments, the tension force applied proximate the first end of the cathode in the arc chamber is less than the tension force applied to the second end to decrease the temperature of the faceplate. In some embodiments, the controller receives an input and determines a desired tension force of the first adjustable tensioning system and a desired tension force of the second adjustable tensioning system based on the input. In certain embodiments, the input is a feed gas species being used, a desired temperature, or a desired force. In some embodiments, each of the first clasp and the second clasp includes a strap, wherein the strap includes an engagement portion seated on the faceplate, and two attachment portions, wherein the two attachment portions are coupled to a respective adjustable tensioning system.

[0010] According to another embodiment, an ion implantation system is disclosed. The ion implantation system includes an ion source comprising: an arc chamber comprising a plurality of chamber walls and having a first end and a second end; and a faceplate having extraction apertures disposed on a top of the plurality of chamber walls; a source housing, wherein the arc chamber is disposed on the source housing; a first clasp and a second clasp for pressing the faceplate against the top of the plurality of chamber walls, wherein the first clasp is disposed proximate to the first end and the second clasp is disposed proximate to the second end; and a first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system being in communication with the first clasp to apply tension to the first clasp, the second adjustable tensioning system being in communication with the second clasp to apply tension to the second clasp; wherein each of the first adjustable tensioning system and the second adjustable tensioning system comprises an actuator and a tensioning system, wherein the tensioning system comprises a yoke for attachment to the respective clasp, a stop bracket, and a spring disposed between the yoke and the stop bracket; and wherein the actuator comprises a shaft, and wherein movement of the shaft changes the distance between the stop bracket and the yoke. In some embodiments, the source housing comprises a housing body having a cylindrical shape, and wherein a flat region is formed on the housing body to mount the tensioning system. In some embodiments, the source housing comprises a flange disposed proximate to the arc chamber, wherein the flange is disposed between the arc chamber and the tensioning system; and wherein the flange comprises a slot for the clasp to pass through. In some embodiments, the actuator comprises a linear actuator, and the shaft is attached to the stop bracket. In some embodiments, each of the first adjustable tensioning system and the second adjustable tensioning system further comprises a ball screw that passes through an interior of the spring and is rotatably coupled to the stop bracket, wherein the actuator comprises a rotary motor and a gear disposed at a distal end of the shaft, wherein the gear engages with a ball screw gear of the rotating ball screw. In certain embodiments, the source housing has a hollow interior, and the tensioning system is mounted on an outer wall of the source housing, and the actuator is disposed within the source housing. In certain embodiments, a slot is disposed in the source housing that connects the hollow interior to the outer wall, wherein the gear extends through the slot to connect the actuator to the tensioning system. In some embodiments, the arc chamber and the source housing are disposed in a vacuum chamber, the tensioning system is mounted on an outer wall of the source housing, and the actuator is disposed outside of the vacuum chamber such that the shaft passes from an atmospheric environment into the vacuum chamber.

[0011] According to another embodiment, an ion implantation system is disclosed. The ion implantation system includes an ion source, the ion source comprising: an arc chamber including a plurality of chamber walls and having a first end and a second end; and a panel having an extraction port disposed on the top of the plurality of chamber walls; a source housing, wherein the arc chamber is disposed on the source housing; a first fastener and a second fastener, the first fastener being disposed near the first end and the second fastener being disposed near the second end; and a first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system communicating with the first fastener to apply tension to the first fastener, and the second adjustable tensioning system communicating with the second fastener to apply tension to the second fastener, wherein the first adjustable tensioning system and the second adjustable tensioning system... Each adjustable tensioning system in the tensioning system includes an actuator; and a controller, communicated with the first and second adjustable tensioning systems, to provide a desired tension to each of the first and second adjustable tensioning systems. The controller supplies command signals to each of the first and second adjustable tensioning systems and receives feedback signals from each of the first and second adjustable tensioning systems, wherein the feedback signals indicate the actual tension experienced by each of the first and second adjustable tensioning systems. In some embodiments, the controller updates the command signals of each of the first and second adjustable tensioning systems based on the corresponding feedback signals. In some embodiments, the controller updates the command signals multiple times. In some embodiments, the controller updates the command signals at least once per minute. Attached Figure Description

[0012] For a better understanding of this disclosure, reference is made to the accompanying drawings, which are incorporated herein by reference and are shown in the drawings:

[0013] FIG. 1A This is a diagram of an ion source according to one embodiment.

[0014] FIG. 1B This is a diagram of the ion source according to the second embodiment.

[0015] FIG. 2 yes FIGS. 1A-1B The image shows a side view of the interior of the ion source.

[0016] FIG. 3 It is a block diagram of the control system.

[0017] FIG. 4 The operation of a control system according to one embodiment is shown.

[0018] FIG. 5 An ion source with an adjustable tension system according to a first embodiment is shown.

[0019] FIGS. 6A-6C An adjustable tensioning system is shown in various embodiments.

[0020] FIG. 7 An ion source with an adjustable tension system according to a second embodiment is shown.

[0021] FIG. 8 An ion source with an adjustable tension system according to a third embodiment is shown.

[0022] FIG. 9 The source housing that can be used for each of the various embodiments is shown.

[0023] FIGS. 10A-10C The theoretical panel temperature gradient is shown under various compressive forces applied to each end of the panel. Detailed Implementation

[0024] As mentioned above, the temperature of the panel in the IHC ion source can affect the deposition rate of material on the inner surface of the panel. During operation, thermal gradients on the panel can cause uneven deposition on the panel and extraction orifice, resulting in uneven ion extraction from the IHC ion source due to the resulting uneven orifice size. This deposition can lead to ion beam inhomogeneity and increased maintenance.

[0025] FIG. 1A An ion source for temperature control of a panel is illustrated according to one embodiment. The ion source 10 includes a plurality of chamber walls 11 defining an arc chamber 200. A panel 40 having an extraction orifice 41 is disposed against the top of the chamber walls 11. The panel 40 may be a single component or may be composed of multiple components. For example, in one embodiment, the panel 40 includes a panel insert disposed below an outer panel and facilitating the definition of the extraction orifice 41. Therefore, as used herein, the term "panel" refers to any one or more components constituting a structure including an extraction orifice for ion removal. Mechanisms for ion formation may be present within the arc chamber 200. For example, in one embodiment, an indirect heating cathode (IHC) may be provided within the arc chamber.

[0026] The panel 40 is secured to the source housing 30 using multiple fasteners (in this embodiment, two strips 50). The source housing 30 may include a flange 31 having holes or slots 32 through which the strips 50 pass. An adjustable tensioning system 100 is used to hold the strips 50 in place. An arc chamber 200 may be attached to the source housing 30. In some embodiments, the source housing 30 may be temperature-controlled. For example, the source housing 30 may be attached to a heat sink or may be a heat sink itself. Thus, the chamber wall 11 is in direct thermal contact with the source housing 30. This serves to cool the chamber wall 11. The source housing 30 may include a lower flange 33. This lower flange 33 separates the vacuum chamber containing the ion source 10 from the atmospheric environment. Thus, components located below the lower flange 33 may be located in the atmospheric environment, while components located above the lower flange 33 may be located in the vacuum chamber.

[0027] Strip 50 may be formed with a rounded rectangular cross-section. The cross-section of strip 50 has a width and a thickness, wherein the width may be greater than the thickness. The width of strip 50 may be between 0.25 inches and 1 inch, and the thickness may be between 1 / 16 inch and ¼ inch. Strip 50 includes three straight portions separated by rounded portions 51. Rounded portions 51 may include bends having a radius of curvature. The radius of curvature of the rounded portions may be between 0.25 inches and 1.00 inch. In some embodiments, the bends are 90° bends, but in other embodiments, the bends may be between 45° and 135°. Joining portions 52 exist between the rounded portions 51. FIG. 1A As seen, the joining portion 52 of the strip 50 is the portion that rests against the outer surface of the panel 40. In some embodiments, the length of the joining portion 52 is slightly longer than the width of the panel 40, such that the joining portion 52 contacts the entire width of the panel 40. For example, although other sizes are possible, the joining portion 52 of the strip 50 may be between 1 inch and 6 inches. An attachment portion 53 is present on opposite sides of each rounded portion 51. Each attachment portion 53 may have a length greater than the height of the arc chamber 200. For example, although other sizes may be used, the attachment portion 53 may have a length between 4 inches and 10 inches. FIG. 1A As best viewed, the attachment portion 53 of the strip 50 can pass through a slot 32 or opening in the flange 31. A hole may be provided near the distal end of each attachment portion 53. This hole is used to attach the strip 50 to the adjustable tension system 100. A first fastener is provided at the first end 201 of the arc chamber 200 (see...). FIG. 2 The second fastener is located near the second end 202 of the arc chamber 200 (see [reference]). FIG. 2Near the cathode side (i.e., the first end 201) of the panel 40, there is a first adjustable tensioning system 100 associated with the cathode side (i.e., the first end 201) of the panel 40 and a second adjustable tensioning system 100 associated with the repulsion side (i.e., the second end 202) of the panel 40.

[0028] The adjustable tensioning system 100 includes a tensioning system 110 (which may include a spring) and an actuator 120 (see [link to relevant documentation]). FIG. 3 Actuator 120 is used to change the length of the spring, which alters the compressive force applied to panel 40 by strip 50. Tensioning system 110 is positioned such that flange 31 is located between arc chamber 200 and tensioning system 110.

[0029] The adjustable tensioning system 100 can be communicated with the controller 70. The controller 70 includes a processing unit 71 and an associated memory device 72 (see [link]). FIG. 3 This memory device 72 contains instructions that, when executed by the processing unit 71, enable the controller 70 to perform the functions set forth herein. This memory device 72 may be non-volatile memory, such as flash read-only memory (ROM), electrically erasable ROM (EEROM), or other suitable means. In other embodiments, the memory device 72 may be volatile memory, such as random access memory (RAM) or dynamic random access memory (DRAM). The processing unit 71 may be a general-purpose computer, a special-purpose computer, a microcontroller, or other type of circuitry. As described in more detail below, the controller 70 may output one or more electrical signals to the actuator 120.

[0030] FIG. 1B An ion source for temperature control of panel 40 according to a second embodiment is shown. Equivalent components are assigned the same reference numerals. In this embodiment, each fastener is a set of two hooks 55 instead of a strip. Each hook may have a rounded end disposed in a groove in the top surface of panel 40. The distal end of each hook may include another rounded end for attachment to an adjustable tension system 100. The remainder of the ion source is similar to... FIG. 1A As shown in the image.

[0031] FIG. 2A side view of an electronic device and its interior according to one embodiment of an ion source 10 is shown. In this embodiment, the ion source 10 includes an arc chamber 200, which includes two opposing ends and chamber walls 11 connected to those ends. The arc chamber 200 also includes a bottom wall and a panel 40. The chamber walls 11 may be made of an electrically and thermally conductive material and may be in electrical contact with each other. A cathode 210 is disposed at a first end 201 of the arc chamber 200. A filament 260 is disposed behind the cathode 210. The filament 260 is connected to a filament power supply 265. The filament power supply 265 is configured to pass current through the filament 260 so that the filament 260 emits thermionic electrons. A cathode bias power supply 215 applies a negative bias voltage to the filament 260 relative to the cathode 210, causing the thermionic electrons to accelerate from the filament 260 toward the cathode 210 and heat the cathode 210 as they impact its rear surface. The cathode bias power supply 215 can apply a bias voltage to the filament 260 such that it has a voltage negative than that of the cathode 210, for example, between 200 volts and 1500 volts. The cathode 210 then emits thermionic electrons into the arc chamber 200 on its front surface.

[0032] Therefore, the filament power supply 265 supplies current to the filament 260. The cathode bias power supply 215 applies a bias voltage to the filament 260, making the filament 260 more negative than the cathode 210, thereby attracting electrons from the filament 260 toward the cathode 210. Alternatively, the cathode power supply 270 can be used to apply an electrical bias voltage to the cathode 210 relative to the arc chamber 200. Due to the power applied to the cathode 210 and the emission of electrons, the arc chamber 200 may become hotter near the cathode 210. This includes the portion of the panel 40 located near the cathode 210.

[0033] In this embodiment, a repulsion electrode 220 is disposed in the arc chamber 200 at the second end 202 opposite to the cathode 210. The repulsion electrode 220 may be connected to a repulsion electrode power supply 225. As its name suggests, the repulsion electrode 220 serves to repel electrons emitted from the cathode 210 back towards the center of the arc chamber 200. For example, the repulsion electrode 220 may be biased with a negative voltage relative to the arc chamber 200 to repel electrons. For example, although other voltages may also be used, the repulsion electrode power supply 225 may have an output in the range of 0 volts to -150 volts. In some embodiments, the repulsion electrode 220 is biased with a voltage between 0 volts and -150 volts relative to the arc chamber 200. In other embodiments, the cathode power supply 270 is also used to supply voltage to the repulsion electrode 220. In other embodiments, the repulsion electrode 220 may be electrically grounded or floating. In other embodiments, the repulsion pole 220 may be omitted.

[0034] In operation, gas is supplied to the arc chamber 200. Thermionic electrons emitted from the cathode 210 cause the gas to form a plasma 250. Ions from this plasma 250 are then extracted via an extraction port 41 in the panel 40. The ions are then manipulated to form an ion beam directed towards the workpiece. An extraction electrode 280 is disposed outside the arc chamber 200 and near the extraction port 41. A bias voltage different from that applied to the arc chamber 200 is applied to the extraction electrode 280 to attract ions from within the arc chamber 200 via the extraction port 41.

[0035] It should be noted that other mechanisms for generating ions may also be used. These other mechanisms include, but are not limited to, Bernas ion sources, radio frequency (RF) antennas, and capacitively coupled sources.

[0036] FIG. 3 A block diagram of a control system for controlling the adjustable tension system 100 is shown. The controller 70 may communicate with an input device 75 (e.g., a keyboard, touchscreen, or other device). The controller 70 is also communicated with two adjustable tension systems 100. As described above, the first adjustable tension system controls the compressive force applied to the panel 40 closest to the first end 201 of the cathode 210, while the second adjustable tension system controls the compressive force applied to the panel 40 opposite the first end 201 and near the repulsion electrode 220 (if present).

[0037] Each adjustable tensioning system 100 includes an actuator 120, which may be a rotary electric motor or a linear actuator, as described in more detail below. Each actuator 120 receives a command signal 121 from a controller 70. The command signal 121 may be an analog signal, a time-varying analog signal with amplitude, period, and duty cycle, or a digital signal. The command signal 121 of the actuator 120 determines the amount of movement (rotary or linear) that the actuator 120 will produce. In some embodiments, each actuator 120 also includes a feedback signal 122, which may represent the torque (for a rotary actuator) or force (for a linear actuator) actually experienced by the actuator 120. Therefore, the feedback signal 122 indicates the tension or compressive force applied to the fastener. This feedback signal 122 is provided to the controller 70, which may use this value to further adjust the command signal 121 of the actuator 120. As described above, the adjustable tensioning system 100 also includes a tensioning system 110, which typically includes at least one spring. In this way, the two adjustable tensioning systems 100 can be controlled independently, and the controller 70 can issue different command signals 121 to each adjustable tensioning system 100. Therefore, the compressive force applied by the first fastener near the first end 201 can be less than, greater than, or equal to the compressive force applied by the second fastener near the second end 202 of the arc chamber 200.

[0038] FIG. 4 Show FIG. 3The operation of the control system is shown below. First, as shown in grid 400, controller 70 receives input, for example, from the operator via input device 75. This input may be a desired force applied to both ends of the IHC ion source to compress the corresponding ends of panel 40 into the chamber wall 11 of the arc chamber. In other embodiments, the input may be a desired temperature of panel 40, the feed gas species being introduced, the tension applied to the fasteners, or a recipe for a list of parameters associated with the operation of ion source 10. Based on this input, as shown in grid 410, controller 70 determines the desired tension for the fasteners (i.e., first end 201) associated with the first adjustable tension system and for the fasteners (i.e., second end 202) associated with the second adjustable tension system. The tension on the fasteners pulls panel 40 downward, which directly translates into an equal amount of compressive force applied between panel 40 and arc chamber 200. The desired tension or compression force can be determined using a lookup table stored in memory device 72 or an equation executed by processing unit 71. As mentioned above, the desired fastener tension may differ for the two adjustable tensioning systems. Then, as shown in grid 420, controller 70 provides the desired tension to each adjustable tensioning system 100 via command signal 121. In some embodiments, controller 70 then receives a feedback signal 122 from actuator 120 indicating the actual torque or force experienced by the actuator, as shown in grid 430. Based on this feedback, controller 70 then adjusts the command signal 121 provided to actuator 120 such that the feedback signal is equal to the desired tension, as shown in grid 440. In some embodiments, the control system repeats grids 430 to 440 throughout the operation of the IHC ion source. For example, over time, the material in the fastener assembly may soften or loosen, thereby reducing the compression force on panel 40. This relaxation can be compensated for by continuously monitoring the feedback signal 122 and adjusting the command signal 121, so that the compression force remains constant over time. In some embodiments, squares 430 to 440 are executed multiple times. In some embodiments, the squares can be executed at regular intervals. In some embodiments, squares 430 to 440 can be executed at a frequency of 1 millisecond to 5 milliseconds. In other embodiments, the squares can be executed less frequently (e.g., at a frequency of 1 second or more). Therefore, the monitoring rate is not limited by this disclosure and can also be any suitable duration, such as every 1 millisecond or more. In some embodiments, squares 430 to 440 can be executed at least once per minute. In some embodiments, squares 430 to 440 can be executed at least once per hour.

[0039] FIG. 5A first embodiment of an ion implantation system including the control system described above is shown. Although a strip 50 is shown, it should be understood that the fastener may also be a hook 55. In this embodiment, each adjustable tensioning system 100 includes an actuator 120, which is a rotary motor 500. In this embodiment, the source housing 30 may have a hollow interior. The rotary motor 500 is located in a cavity within the source housing 30 disposed in a vacuum chamber. The rotary motor 500 is coupled to a shaft 510 on which a gear 520 is mounted. A slot 35 is provided in the wall of the source housing 30 (see...). FIG. 9 This allows the gear 520 from the rotary motor 500 to pass through the wall of the source housing 30 and engage with the tensioning system 110. The tensioning system 110 is mounted on the outer wall of the source housing 30. The tensioning system 110 includes a yoke 610 for coupling fasteners to the tensioning system 110. Although FIG. 5 A rotary motor 500 is shown disposed within a vacuum chamber, but other embodiments are also possible. For example, the rotary motor 500 may be located outside the vacuum chamber, such as in the atmosphere on the opposite side of the lower flange 33 of the source housing 30. A vacuum flange (not shown) may be used to allow the shaft 510 to access the vacuum chamber from the atmosphere.

[0040] FIGS. 6A-6C The tensioning system 110 is shown in more detail. In this embodiment, the tensioning system 110 includes an upper mounting bracket 620 and a lower mounting bracket 625, both of which are attached to the outer wall of the source housing 30. A yoke 610 attached to the fastener includes two arms 611 and a central portion 612. The central portion 612 is inserted between the upper mounting bracket 620 and the lower mounting bracket 625 and includes a hole. A stop bracket 640 compresses a spring 650 such that the spring 650 is positioned between the underside of the stop bracket 640 and the top surface of the central portion 612 of the yoke 610. The stop bracket 640 may include one or more guide rails 645 extending through the central portion 612 to the lower mounting bracket 625. The guide rails 645 may be used to ensure stable uniaxial movement of the stop bracket 640. A ball screw 630 is inserted through an opening in the lower mounting bracket 625. The shaft of the ball screw 630 passes through a hole in the central portion 612 of the yoke 610 and is disposed inside the spring 650. The ball screw 630 passes through an opening in the stop bracket 640. A threaded fastener 670 (e.g., a nut or other suitable component) is then screwed onto the end of the ball screw 630 and engaged with the top surface of the stop bracket 640. One end of the ball screw 630 (e.g., the end closest to the lower mounting bracket 625) includes a ball screw gear 631 that engages with the gear 520. The spring 650 applies a downward force on the central portion 612 of the yoke 610. This force is related to the distance between the central portion 612 and the lower side of the stop bracket 640.FIG. 6B The tensioning system 110 is shown in the position where the spring length is at its maximum and the force exerted by the spring 650 is at its minimum. The stop bracket 640 is located at its uppermost position, allowing the spring 650 to have its maximum length. FIG. 6C The diagram illustrates the tensioning system after the ball screw 630 has been rotated multiple times to bring the stop bracket 640 closer to the lower mounting bracket 625. The shorter length of the spring 650 results in a greater downward force on the central portion 612 of the yoke 610. Therefore, in operation, when the rotary motor 500 is actuated, it causes the gear 520 coupled to the ball screw gear 631 to rotate. The rotation of the ball screw gear 631 causes a linear movement of the stop bracket 640, which alters the compression of the spring 650, thereby determining the compressive force applied to the panel 40 by the fastener. It should be noted that although the diagram shows the ball screw gear 631 near the lower mounting bracket 625, this configuration can be modified so that the ball screw gear is near the upper mounting bracket 620.

[0041] FIG. 7 A second embodiment of the adjustable tensioning system is shown. In this embodiment, the tensioning system 110 is as follows: FIGS. 6A-6C As shown in the diagram. However, in this embodiment, the shaft 510 and gear 520 are located outside the source housing 30. The shaft 510 and gear 520 are located within the vacuum chamber. In some embodiments, the rotary motor 500 is located outside the vacuum chamber, for example, on the atmospheric environment opposite the lower flange 33 of the source housing 30. The vacuum flange 700 can be used to allow the shaft 510 to access the vacuum chamber from the atmospheric environment. In other embodiments, the rotary motor 500 may be located within the vacuum chamber. This configuration allows additional space within the cavity of the source housing 30 to accommodate other components.

[0042] FIG. 8 A third embodiment of the ion source is shown. In this embodiment, actuator 120 is a linear actuator 800, which has a shaft 810 that moves linearly. The shaft 810, instead of a ball screw, passes through a hole in the central portion 612 of the lower mounting bracket 625, the yoke 610, and through the interior of the spring 650. The shaft 810 is attached to a stop bracket 640. The remainder of the tensioning system 110 is similar to... FIGS. 6A-6C As shown in the figure. The linear actuator 800 can be disposed within a vacuum chamber, such as... FIG. 8 As shown in the diagram. In another embodiment, with... FIG. 7 Similarly, in this configuration, the linear actuator 800 is located in the atmospheric environment. In this embodiment, the shaft 810 passes through the lower flange 33 of the source housing 30 and extends to the stop bracket 640. In this embodiment, movement of the shaft 810 directly causes linear movement of the stop bracket 640 and compresses the spring 650.

[0043] Of course, the tensioning system 110 can also be implemented in other ways, and the tensioning system 110 is not limited to the tensioning system shown herein.

[0044] FIG. 9 The source housing 30 is shown in more detail. This source housing 30 can be used in any of the embodiments described above. As described above, the source housing 30 has a flange 31 located at or near the top surface. The flange 31 has a plurality of openings or slots 32 for fasteners to pass through. In some embodiments, a total of four slots 32 may be present. The bottom of the source housing 30 may include a lower flange 33. The source housing 30 includes a housing body 34, which is defined as the area between the flange 31 and the lower flange 33. In some embodiments, the interior of the housing body 34 may be hollow, thereby enabling the inclusion of components (e.g., actuators, such as...) FIG. 5 (As shown in the diagram). The exterior of the housing body 34 may be cylindrical. Two areas on opposite sides of the housing body 34 may be machined to form a flat surface 36. While other dimensions are possible, the flat surface 36 may have a width between 1 inch and 3 inches and a height between 2 inches and 5 inches. The flat surface 36 forms a location for mounting each tensioning system 110. This flat surface 36 can be used for... FIG. 5 , FIG. 7 and FIG. 8 The tensioning system 110 of any of the embodiments shown is installed. A slot 35 may be positioned within each flat surface 36, extending from the interior to the exterior of the housing body 34. The slot 35 allows a coupling (e.g., a gear) to extend from the interior to the exterior of the housing body 34. FIG. 5 The embodiments shown are useful. It should be noted that in other embodiments, slot 35 may not be present.

[0045] The embodiments described above in this application have numerous advantages. In one system design, the cathode 210 is heated to a temperature that allows heat to be conducted from the chamber wall 11 to the panel 40. FIG. 10A The diagram illustrates the temperature distribution of panel 40 under equal, moderate compressive forces at each end of the panel. It should be noted that approximately half of the extraction orifices 41 are in the medium-high temperature range, while the other half are in the medium-low temperature range. Under these force conditions, the temperature difference between the high-temperature and low-temperature portions of the panel can exceed 200°C. Therefore, each temperature range may represent 50°C or greater. FIG. 10BIn this process, the compressive force is increased at the second end 202 of panel 40, while the compressive force is decreased at the first end 201 of panel 40. The thermal resistance gradient created between panel 40 and chamber wall 11 reduces heat conduction from the first end 201 to panel 40 and also increases the ability of the second end 202 of arc chamber 200 to act as a heat sink. Therefore, the temperature of extraction orifice 41 decreases, resulting in approximately half of extraction orifice 41 being in a low-temperature range, while the remainder is in a medium-low temperature range. Thus, by making the compressive force at the first end 201 less than the compressive force at the second end 202, the overall temperature of panel 40 can be reduced. FIG. 10C In this process, the compressive force is increased on the cathode side (i.e., the first end 201) of the panel 40, while the compressive force is decreased on the repulsion side (i.e., the second end 202) of the panel 40. The resulting thermal contact gradient causes more heat to be conducted from the first end 201 to the panel 40 and also reduces the ability of the second end 202 of the arc chamber 200 to act as a heat sink. Therefore, the entire extraction orifice 41 is now in a high-temperature range. Therefore, by making the compressive force at the first end 201 greater than the compressive force at the second end 202, the overall temperature of the panel 40 can be increased.

[0046] The scope of this disclosure is not limited to the specific embodiments described herein. In fact, based on the foregoing description and drawings, various other embodiments and modifications of this disclosure will become apparent to those skilled in the art in addition to those described herein. Therefore, such other embodiments and modifications are intended to fall within the scope of this disclosure. Furthermore, although this disclosure has been set forth herein for a specific purpose, in a specific setting, and in the context of a specific implementation, those skilled in the art will recognize that its effectiveness is not limited thereto and that this disclosure can be advantageously practiced for any number of purposes and in any number of settings. Therefore, the following claims should be interpreted in accordance with the full scope and spirit of this disclosure as set forth herein.

Claims

1. An ion implantation system, comprising: Ion sources, including: An electric arc chamber, comprising multiple chamber walls and having a first end and a second end; and The panel has an extraction port disposed on the top of the walls of the plurality of chambers; Source housing, wherein the arc chamber is disposed on the source housing; A first fastener and a second fastener are used to press the panel against the top of the plurality of chamber walls of the arc chamber, wherein the first fastener is disposed near the first end and the second fastener is disposed near the second end; and A first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system being connected to the first fastener to apply tension to the first fastener, and the second adjustable tensioning system being connected to the second fastener to apply tension to the second fastener; and The controller, connected to the first and second adjustable tensioning systems, is configured to apply different tensions to each of the first and second fasteners.

2. The ion implantation system of claim 1, wherein the tension applied to the first end of the cathode near the arc chamber is greater than the tension applied to the second end to increase the temperature of the panel.

3. The ion implantation system of claim 1, wherein the tension applied to the first end of the cathode near the arc chamber is less than the tension applied to the second end to reduce the temperature of the panel.

4. The ion implantation system of claim 1, wherein the controller receives input and determines, based on the input, the desired tension of the first adjustable tension system and the desired tension of the second adjustable tension system.

5. The ion implantation system of claim 4, wherein the input is the feed gas species being used, the desired temperature, or the desired force.

6. The ion implantation system of claim 1, wherein each of the first fastener and the second fastener comprises a strip, wherein the strip comprises an engagement portion disposed on the panel and two attachment portions, wherein the two attachment portions are coupled to a corresponding adjustable tensioning system.

7. An ion implantation system, comprising: Ion sources, including: An electric arc chamber, comprising multiple chamber walls and having a first end and a second end; and The panel has an extraction port disposed on the top of the walls of the plurality of chambers; Source housing, wherein the arc chamber is disposed on the source housing; A first fastener and a second fastener are used to press the panel against the top of the plurality of chamber walls, wherein the first fastener is disposed near the first end and the second fastener is disposed near the second end; and A first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system being connected to the first fastener to apply tension to the first fastener, and the second adjustable tensioning system being connected to the second fastener to apply tension to the second fastener; wherein each adjustable tensioning system in the first and second adjustable tensioning systems includes an actuator and a tensioning system, wherein the tensioning system includes a yoke for attachment to the corresponding fastener, a stop bracket, and a spring disposed between the yoke and the stop bracket; and wherein the actuator includes a shaft, and wherein movement of the shaft changes the distance between the stop bracket and the yoke.

8. The ion implantation system of claim 7, wherein the source housing comprises a housing body having a cylindrical shape, and wherein a flat area is formed on the housing body for mounting the tensioning system.

9. The ion implantation system of claim 7, wherein the source housing includes a flange disposed near the arc chamber, wherein the flange is disposed between the arc chamber and the tensioning system; and wherein the flange includes a slot through which the fastener passes.

10. The ion implantation system of claim 7, wherein the actuator comprises a linear actuator and the shaft is connected to the stop bracket.

11. The ion implantation system of claim 7, wherein each of the first and second adjustable tension systems further comprises a ball screw passing through the interior of the spring and rotatably coupled to the stop bracket, wherein the actuator comprises a rotary motor and a gear disposed at the distal end of the shaft, wherein the gear engages with a ball screw gear that rotates the ball screw.

12. The ion implantation system of claim 11, wherein the source housing has a hollow interior, wherein the tensioning system is mounted on the outer wall of the source housing, and the actuator is disposed within the source housing.

13. The ion implantation system of claim 12, wherein a slot is provided in the source housing to connect the hollow interior to the outer wall, wherein the gear extends through the slot to connect the actuator to the tensioning system.

14. The ion implantation system of claim 7, wherein the arc chamber and the source housing are disposed in a vacuum chamber, the tensioning system is mounted on the outer wall of the source housing, and the actuator is disposed outside the vacuum chamber, such that the shaft is accessible from the atmospheric environment into the vacuum chamber.

15. An ion implantation system, comprising: Ion sources, including: An electric arc chamber, comprising multiple chamber walls and having a first end and a second end; and The panel has an extraction port disposed on the top of the walls of the plurality of chambers; Source housing, wherein the arc chamber is disposed on the source housing; A first fastener and a second fastener, the first fastener being disposed near the first end, and the second fastener being disposed near the second end; and A first adjustable tensioning system and a second adjustable tensioning system, the first adjustable tensioning system being connected to the first fastener to apply tension to the first fastener, and the second adjustable tensioning system being connected to the second fastener to apply tension to the second fastener, wherein each adjustable tensioning system in the first and second adjustable tensioning systems includes an actuator; and A controller, connected to the first and second adjustable tension systems, provides a desired tension to each of the first and second adjustable tension systems, wherein the controller supplies command signals to each of the first and second adjustable tension systems and receives feedback signals from each of the first and second adjustable tension systems, wherein the feedback signals indicate the actual tension experienced by each of the first and second adjustable tension systems.

16. The ion implantation system of claim 15, wherein the controller updates the command signal of each adjustable tension system in the first and second adjustable tension systems based on corresponding feedback signals.

17. The ion implantation system of claim 16, wherein the controller updates the command signal multiple times.

18. The ion implantation system of claim 17, wherein the controller updates the command signal at least once per minute.

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