JPH0543500U - High frequency quadrupole linear accelerator - Google Patents

Abstract

(57) [Summary] [Structure] The opening of the vacuum container 1 accommodating the electrode assembly 2 in which four electrodes are supported by a supporting member is openable and closable to separate the vacuum atmosphere side from the atmosphere side. A door member 25 is provided. Refrigerant passages are provided inside the electrodes of the electrode assembly 2 and the support member, so that a plurality of refrigerant introduction and
The outlet pipes 16 to 18 are connected to the refrigerant passages of the electrode assembly 2. A predetermined portion of each of the plurality of refrigerant introducing / discharging pipes 16 to 18 is connected by a flange member 19, and the flange member 19 is bolted to the through hole 2 of the door member 25.
It is attached to 5b. [Effect] Since the electrode assembly 2 can be easily attached to and detached from the vacuum container 1 and the device can be assembled and disassembled quickly, productivity and maintainability can be improved.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a high frequency quadrupole (hereinafter referred to as RFQ: Radio Frequency Quadrupole) type linear accelerator used in, for example, an ion implantation apparatus, and more particularly to a cooling mechanism thereof.

[0002]

[Prior Art]

 The ion implanter ionizes the impurities to be diffused, selectively extracts these impurity ions by mass spectrometry using a magnetic field, accelerates them by an electric field, and irradiates the ion irradiation target to irradiate the ion irradiation target. Impurities are injected into. Since this ion implanter can implant impurities that determine the characteristics of the device in the semiconductor process to an arbitrary amount and depth with good controllability, it is an important device for manufacturing the present integrated circuits. There is.

In recent years, semiconductor device manufacturers have been increasingly required to have a MeV class high energy ion implanter having advantages such as formation of a retrograde well in a C-MOS device manufacturing process and post-ROM writing.

An RF Q linear accelerator has been conventionally used as an ion accelerating means in the high-energy ion implantation apparatus. In this RFQ linear accelerator, as shown in FIG. 9, four rod-shaped electrodes 52 to 55 are arranged in a cylindrical vacuum container 51 at intervals of 90 ° around a horizontal axis. There is a so-called 4 Rod-RFQ type linear accelerator having a structure in which these electrodes are supported by conductive posts 56 and 57. The 4Ro d-RFQ linear accelerator receives high-frequency power supplied from a high-frequency power source (not shown) and accelerates ions to a predetermined high energy.

The post 56 supports a pair of diagonally opposed electrodes 52 and 53, and the post 57 also supports a pair of diagonally opposed electrodes 54 and 55. The posts 56 and 57 supporting the electrodes 52 to 55 are erected on the conductive base 58 to form an electrode assembly 59 mounted in the vacuum container 51.

Since a large high-frequency current flows through the surfaces of the electrodes 52 to 55, the posts 56 and 57, and the base 58, the temperature of these members rises. Usually, in order to prevent the temperature rise of each member, a cooling liquid passage for flowing a cooling liquid such as water is formed inside each member. Then, for the purpose of connecting the cooling liquid passage of each member and a circulation pump (not shown), the cooling liquid is introduced into / out of the cooling liquid passage from the electrodes 52 to 55 of the electrode assembly 59 and the base 58. A plurality of cooling liquid inlet / outlet pipes 60 ... (Only the cooling liquid inlet / outlet pipes connected to the base 58 are shown in the same figure) penetrate the wall of the vacuum container 51 and the circulation pump outside the container. Extending to.

In assembling the 4 Rod-RFQ type linear accelerator, first, the electrode assembly 59 is assembled outside the vacuum container 51, and a plurality of cooling liquid introducing / deriving tubes 60 ... Are connected by welding or brazing. Then, the electrode assembly 59 to which the plurality of cooling liquid introducing / discharging pipes 60 ... Are connected is fixed to a predetermined position in the vacuum container 51. At this time, a vacuum seal is provided by an O-ring or the like between the cooling liquid inlet / outlet pipes 60 ... And the empty container 51, and, for example, a stainless wire whose surface is silver-plated is clamped and tightened. A so-called high-frequency seal (hereinafter referred to as an RF seal) for making electrical contact is provided.

[0008]

[Problems to be solved by the device]

 However, in the above-mentioned conventional 4 Rod-RFQ type linear accelerator, since the plurality of cooling liquid introducing / deriving pipes 60 ... Connected to the electrode assembly 59 extend in the direction penetrating the wall of the vacuum container 51, these cooling liquids are introduced. The liquid inlet / outlet pipes 60 ... Are obstructive, and the electrode assembly 59 cannot be smoothly taken in and out of the vacuum container 51. Further, the vacuum seal and the RF seal between the plurality of cooling liquid introducing / extracting pipes 60 ... And the vacuum container 51 need to be performed for each cooling liquid introducing / extracting pipe 60.

Therefore, the work of attaching the electrode assembly 59 assembled outside the vacuum container 51 to the vacuum container 51 is a complicated and time-consuming work for the operator. Therefore, the conventional 4Rod-RFQ linear accelerator has poor productivity and is not suitable for mass production.

By the way, it is inevitable that the entering ions collide with the electrodes 52 to 55, and the electrodes 52 to 55 are contaminated. Furthermore, when the resonance frequency fluctuates or discharge occurs due to a cause such as the electrodes 52 to 55 flexing with time, it is necessary to disassemble the 4 Rod-RF Q type linear accelerator for maintenance. Occurs. Also in this case, for the above reason, the disassembly of the device and the assembly after the maintenance cannot be easily performed.

The present invention has been made in view of the above, and an object thereof is to make it possible to easily and quickly put an electrode assembly in and out of a vacuum container, and improve productivity and maintainability of 4Rod-RFQ. To provide a type linear accelerator.

[0012]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the 4Rod-RFQ type linear accelerator of the present invention has a cylindrical vacuum container and four rods arranged around the passage of accelerated particles passing through the vacuum container. An electrode assembly in which an electrode is supported by a supporting member, and a refrigerant passage through which a refrigerant passes is provided inside the electrode and / or the supporting member, and is connected to the refrigerant passage to prevent a vacuum atmosphere. The following measures are taken in a high-frequency quadrupole linear accelerator having a plurality of refrigerant inlet / outlet pipes extending to the.

That is, the predetermined portions of the plurality of refrigerant inlet / outlet pipes are connected by the flange member, and the opening / closing opening for separating the vacuum atmosphere side and the atmosphere side is provided at the opening of the vacuum container. A flexible door member is provided, and a through hole smaller than the flange member is formed in the door member for passing the plurality of refrigerant introduction / outlet pipes. The flange member is a mounting means such as a bolt. Is attached to the door member so as to close the through hole.

[0014]

[Action]

 According to the above configuration, the electrode assembly including the four electrodes supported by the support member is provided in the vacuum container. The opening of the vacuum container is provided with an openable / closable door member for separating the vacuum atmosphere side and the atmosphere side. The electrode assembly is opened and closed by opening the door member.

A coolant passage is provided inside the electrode and / or the support member of the electrode assembly, and a plurality of coolant introducing / discharging pipes are connected to the coolant passage. A predetermined portion of the plurality of refrigerant inlet / outlet pipes is connected by a flange member, and if the flange member is attached to the door member by the attaching means, the plurality of refrigerant inlet / outlet pipes are connected to the door member. It goes out from the inside of the vacuum container to the atmosphere side through the through hole.

As described above, since the predetermined portions of the plurality of refrigerant introduction / outlet pipes are connected together by the flange member, the refrigerant can be cooled by vacuum sealing and RF sealing only between the flange member and the door member. It is possible to take out a plurality of refrigerant introducing / extracting pipes to the atmosphere side without performing vacuum seal and RF seal for each introducing / extracting pipe.

Further, since the tips of the refrigerant introducing / extracting pipes attached to the electrode assembly extend together in the direction of the opening of the vacuum container through which the electrode assembly enters and exits the vacuum container, they are extended together by the flange member. The refrigerant inlet / outlet piping does not get in the way when the electrode assembly is moved in and out of the vacuum container. Therefore, the work of mounting the electrode assembly in the vacuum container can be performed easily and quickly. Further, the electrode assembly can be quickly taken out of the vacuum container by removing the attaching means which attaches the flange member to the door member and opening the door member.

[0018]

【Example】

 An embodiment of the present invention will be described below with reference to FIGS.

The 4 Rod-RFQ linear accelerator 10 according to the present embodiment is applied to a high energy ion implanter as shown in FIG. 8, but the present invention is not limited to this.

In the above-mentioned ion implantation apparatus, the ions extracted from the ion source 31 by the extraction power source 32 are subjected to mass analysis by the mass analyzer 33, and only ions of a predetermined mass are selectively extracted to the electrostatic acceleration tube 34. be introduced. The electrostatic accelerating tube 34 accelerates the ions to an energy suitable for the 4 Rod-RFQ type linear accelerator 37 by the acceleration power source 35. The accelerated ions are shaped by a focusing system 36 such as a Q lens, and then introduced into a 4 Rod-RFQ type linear accelerator 37. The 4Rod-RFQ linear accelerator 37 receives the high frequency power from the high frequency power supply 38 and accelerates the ions to a predetermined high energy. After that, the high energy ions are applied to a target 39 such as a wafer in an implantation chamber (not shown).

As shown in FIG. 3, the 4 Rod-RFQ linear accelerator 37 includes a cylindrical vacuum container 1 and an electrode assembly 2 provided inside the vacuum container 1.

The electrode assembly 2 includes four rod-shaped copper electrodes 3 to 6 (see FIG. 1), which are arranged at 90 ° intervals from each other around the passage of ions as the accelerated particles. ), A conductive (copper) flat plate-shaped base (supporting member) 7, and a conductive (copper) post that stands on the base 7 and supports a pair of diagonally opposite electrodes 3 and 4. (Supporting members) 8 and 9 and conductive (copper) posts (supporting members) 10 and 11 that are also erected on the base 7 and that support a pair of diagonally opposed electrodes 5 and 6. It is composed of

Modulation is formed on the facing surfaces of the pair of electrodes 3 and 4 and the facing surfaces of the electrodes 5 and 6 which are diagonally opposed to each other, and the modulation of the electrodes 3 and 4 and that of the electrodes 5 and 6 are performed. It is 180 degrees out of phase with modulation. The 4Rod-RFQ linear accelerator 37 is a resonator in which two pairs of electrodes (3.4 and 5.6) are coupled by the capacitance between the electrodes and the inductance of the post 8.9, and a high frequency power supply By supplying high frequency power of a predetermined frequency from 38 (see FIG. 8) and causing resonance so as to form a quadrupole electric field on the center axis of the electrode, the ion passing through the center of the electrode is accelerated to a predetermined energy.

In this case, a large high-frequency current flows through the surfaces of the electrodes 3 to 6, the base 7, and the posts 8 to 11, so that the temperature of these members rises. Therefore, cooling liquid passages (refrigerant passages) 3a to 11a (see FIGS. 3 and 4) through which a cooling liquid (refrigerant) flows are formed inside each of the electrodes 3 to 6, the base 7 and the posts 8 to 11. There is.

In the case of the present embodiment, as shown in FIG. 4, the cooling liquid passages 3 a and 4 a formed inside the electrodes 3 and 4 communicate with each other through the connection pipe 12 attached to the post 9. is doing. The connection pipe 12 is made of a stainless pipe 12a, a flexible tube 12b, and stainless steel joint portions 12c and 12c having a surface plated with copper, and is fixed to the post 9 by fixing tools 13 and 13. To be done.

As shown in FIGS. 6 and 7, the joint between the joint 12c and the electrode 4 seals the cooling liquid and vacuum with an O-ring 14, and also has a claw 12d protruding from the outer periphery of the joint 12c. And makes electrical contact. That is, if the joint portion 12c is fastened to the electrode 4 with the bolts 15 ..., the stainless claws 12d protruding on the outer periphery of the joint portion 12c will bite into the copper electrode 4a, and electrical contact can be obtained. .. In addition, the connection part between all the joint parts and the electrodes or the base is as described above.

As shown in FIG. 5, the electrode 3 is provided with a first introducing pipe (refrigerant introducing / extracting pipe) 16 for introducing the cooling liquid from the outside of the vacuum container 1 into the cooling liquid passage 3 a, and the electrode 3 is also provided. A first outlet pipe (refrigerant inlet / outlet pipe) 17 that guides the cooling liquid from the cooling liquid passage 4 a to the outside of the vacuum container 1 is connected to 4. As shown in FIGS. 1 and 5, the first inlet pipe 16 and the first outlet pipe 17 are fixed by fixing tools 13 ... And attached to the base 7 and the post 8.

The first introduction pipe 16 includes a joint portion 16a, a stainless pipe 16b, a flexible tube 16c, a copper bellows 16d, and a quick connector 16e, and a copper bellows 16d and a quick connector 12c. A flange member 19 is formed between them.

The first outlet pipe 17 is composed of a joint portion 17a, a stainless pipe 17b, a flexible tube 17c, a copper bellows 17d, and a quick connector 17e, and a copper bellows 17d and a quick connector. A flange member 19 is formed between the first introduction pipe 16 and 17e.

Further, similarly to the above, the cooling liquid passages 5 a and 6 a (see FIG. 4) formed inside the electrodes 5 and 6 are connected to the connection pipe 20 (see FIG. 2) attached to the post 10. A second inlet pipe (refrigerant inlet / outlet pipe) 21 for introducing a cooling liquid to the electrode 5, and a first inlet pipe for discharging the cooling liquid to the outside of the vacuum container 1 to the electrode 6. The two outlet pipes (refrigerant inlet / outlet pipe) 22 are connected.

Further, in this embodiment, the cooling liquid passages 7a to 11a formed inside the base 7 and the posts 8 to 11 communicate with each other, and the cooling liquid is connected to one end of the base 7 with the cooling liquid. A third inlet pipe (refrigerant inlet / outlet pipe) 18 is introduced into the passage 7a, and a third outlet pipe (refrigerant is introduced into the other end of the base 7 to guide the cooling liquid from the cooling liquid passage 7a to the outside of the vacuum container 1 Inlet / outlet pipe) 23 is connected.

The third introduction pipe 18 is composed of a stainless steel joint portion 18b having a surface plated with copper, a copper bellows 18c, and a quick connector 17e. The copper bellows 18b and the quick connector 18c are provided. A flange member 19 is formed between them and is connected to the first introduction pipe 16 and the first discharge pipe 17. The third outlet pipe 23 also has the same structure as the third inlet pipe 18.

As described above, the flange member 19 is a member that bridges the first introduction pipe 16, the first lead-out pipe 17, and the third introduction pipe 18, and is, for example, a flange member 19 having three through holes. It is produced by welding copper bellows 16d, 17d, 18b to one surface (vacuum side) and attaching quick connectors (detachable one-touch piping joints) 16e, 17e, 18c to the other surface (atmosphere side).

The flange member 19 is provided in one opening of the vacuum container 1, and the other opening has a second introduction pipe 21 and a second discharge pipe 22 as shown in FIG. A flange member 24 that bridges the third outlet pipe 23 is provided.

Further, door members 25 and 26 are attached to both openings of the vacuum container 1 by hinges 28 so as to be openable and closable. The door member 25 (26) is provided with a beam passage hole 25a (26a) for securing an ion beam passage path. Further, the door member 25 (26) is provided with a through hole 25b (26b) smaller than the flange member 19 (24) through which the introduction / outlet pipes 16 to 18 (21 to 23) pass.

The flange member 19 is attached to the door member 25 from the vacuum side so as to close the through hole 25b, and is fixed from the atmosphere side by the bolts 27, 27 as an attaching means. In this case, an O-ring and a silver-plated stainless wire are sandwiched between the flange member 19 and the door member 25, and a vacuum seal and an RF seal are provided. The flange member 24 is also attached to the door member 26 in the same manner as the flange member 19.

The procedure for assembling the 4Rod-RFQ type linear accelerator 37 in the above configuration will be described below.

First, the electrode assembly 2 is assembled from the electrodes 3 to 6, the base 7, and the posts 8 to 11 outside the vacuum container 1 using bolts (not shown). After this, at the predetermined position of the electrode assembly 2, the coolant introducing / extracting pipe (first introducing pipe 16, first extracting pipe 17, third introducing pipe 18, second introducing pipe 21, second introducing pipe 22, second introducing pipe 22, 3 Detach piping 23) and connect piping 12 and 20.

Then, the door members 25 and 26 are attached to the opening portions of the vacuum container 1 by hinges 28 so as to open and close automatically. Then, the door members 25 and 26 are opened, the electrode assembly 2 to which the above-mentioned pipe is attached is put into the vacuum container 1, and is fixed at a predetermined position with a bolt (not shown).

After that, an O ring is provided between the opening of the vacuum container 1 and the door members 25 and 26, between the door member 25 and the flange member 19, and between the door member 26 and the flange member 24. The door members 25 and 26 are closed with the RF seal and the RF seal interposed therebetween. Then, the door members 25 and 26 are fixed to the opening of the vacuum container 1 with bolts (not shown). Further, the flange member 19 is attached to the through hole 25b of the door member 25 and the flange member 24 is attached to the through hole 25b of the door member 25 by bolts 27 from the outside of the vacuum container 1, respectively.

A cooling liquid pipe (not shown) connected to a circulation pump (not shown) is connected to the atmosphere-side quick connectors 16e, 17e, 18 of the flange member 19 and the atmosphere-side quick connector of the flange member 24 with one touch. Connecting.

As described above, in the 4 Rod-RFQ linear accelerator 37 of the present embodiment, the plurality of cooling liquid introducing / deriving pipes 16 to 18 (21 to 23) are linked by the flange member 19 (24) to be assembled. Therefore, if the vacuum seal and the RF seal are performed only between the flange member 19 (24) and the door member 25 (26), the vacuum seal and the RF pipe can be vacuum sealed and cooled individually for each cooling liquid introducing / deriving pipe. It is possible to take out a plurality of refrigerant inlet / outlet pipes to the atmosphere side without having to perform RF sealing.

Further, in the 4 Rod-RFQ type linear accelerator 37 of the present embodiment, the cooling liquid introducing / deriving pipes 16 to 18 (21 to 23) are the door members 25 (26) provided at the opening of the vacuum container 1. Through to the atmosphere side. That is, the tips of the cooling liquid inlet / outlet pipes 16 to 18 (21 to 23) attached to the electrode assembly 2 are gathered by the flange member 19 (24) in the direction of moving the electrode assembly 2 into and out of the vacuum container 1. Since it is extended, when the electrode assembly 2 is moved in and out of the vacuum container 1, the coolant introduction / outlet pipes 16 to 18 (21 to 23) do not interfere.

Therefore, the work of mounting the electrode assembly 2 assembled outside the vacuum container 1 and having the cooling liquid introducing / deriving pipes 16-18 and 21-23 attached to the vacuum container 1 can be performed simply and quickly, The productivity of the 4 Rod-RFQ linear accelerator will be improved compared to the conventional one.

Further, in the present 4 Rod-RFQ type linear accelerator 37, copper bellows 16d, 17d, 18b and flexible tubes 16c, 17c are used for the coolant introducing / deriving pipes 16-18 (same for 21-23). Therefore, strain due to vacuuming, strain due to heat change, or distortion during assembly are absorbed by these. (The same applies to the cooling liquid inlet / outlet pipes 21 to 23.) Further, since the cooling liquid inlet / outlet pipes of the 4Rod-RFQ linear accelerator 37 are all attached to the electrode assembly 2 by bolts without using welding, The entire coolant inlet / outlet pipe can be replaced.

When it is necessary to disassemble the 4 Rod-RFQ linear accelerator 37 for maintenance due to contamination of the electrodes 3 to 6 or the like, the disassembly is performed as follows.

First, the coolant pipe on the atmosphere side connected to the quick connectors 16e, 17e, and 18c is removed (one-touch), and then the flange member 19 is fixed to the door member 25 by the bolts 27 and 27 and the flange. The bolts fixing the member 24 to the door member 26 and the bolts fixing the door members 25 and 26 to the opening of the vacuum container 1 are removed to open the door members 25 and 26. Then, the bolts fixing the electrode assembly 2 to the vacuum container 1 are removed, the electrode assembly 2 is taken out from the vacuum container 1, and the electrode assembly 2 is disassembled.

As described above, the device can be disassembled quickly, and assembling after maintenance is easy as described above. Therefore, the maintainability can be improved as compared with the conventional case.

In this embodiment, the three cooling liquid introducing / discharging pipes are connected by the flange member, but the invention is not limited to this, and two or four or more cooling liquid introducing pipes are introduced. -The outlet pipe may be connected by a flange member.

[0050]

[Effect of the device]

 As described above, the 4 Rod-RFQ linear accelerator according to the present invention has a plurality of refrigerant introducing / extracting pipes in which predetermined portions of these are connected by a flange member, and a vacuum atmosphere is formed in the opening of the vacuum container. There is provided a door member that can be opened and closed to separate the side from the atmosphere side, and this door member is provided with a through hole that is smaller than the flange member, through which the plurality of refrigerant introduction / outlet pipes pass. The flange member is attached to the door member by an attaching means so as to close the through hole.

Therefore, if the vacuum seal and the RF seal are provided only between the flange member and the door member, it is possible to perform the vacuum seal and the RF seal for each of the refrigerant introducing / extracting pipes unlike the conventional case. Multiple refrigerant inlet / outlet pipes can be taken out to the atmosphere side. In addition, the tip of the refrigerant inlet / outlet pipe attached to the electrode assembly extends together in the direction of the opening of the vacuum container that allows the electrode assembly to move in and out of the vacuum container. Refrigerant inlet / outlet piping does not get in the way when moving in and out of the vacuum container.

Therefore, the electrode assembly can be easily attached to and detached from the vacuum container, and the device can be assembled and disassembled quickly, so that the productivity and the maintainability can be improved.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, 4 Rod
FIG. 3 is a schematic cross-sectional view of an RFQ linear accelerator.

FIG. 2 is a schematic perspective view showing an electrode assembly of the 4Rod-RFQ linear accelerator.

FIG. 3 is a schematic vertical sectional view of the 4Rod-RFQ linear accelerator.

FIG. 4 is a schematic vertical sectional view showing an electrode assembly of the 4Rod-RFQ linear accelerator.

FIG. 5 is a schematic vertical sectional view showing an electrode assembly of the 4Rod-RFQ linear accelerator.

FIG. 6 is a schematic plan view showing a connecting portion between an electrode and a joint portion in the electrode assembly.

FIG. 7 is a schematic vertical sectional view showing a connecting portion between an electrode and a joint portion in the electrode assembly.

FIG. 8 is a schematic configuration diagram showing an example of a high ion implanter using the 4 Rod-RFQ linear accelerator.

FIG. 9 shows a conventional example and is a schematic vertical sectional view of a 4 Rod-RFQ linear accelerator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Vacuum container 2 Electrode assembly 3-6 Electrode 3a-11a Cooling liquid path (refrigerant passage) 7 Base (supporting member) 8-11 Post (supporting member) 16 1st introduction piping (refrigerant introduction and derivation piping) 17 1st derivation Piping (refrigerant introduction / delivery piping) 18 Third introduction piping (refrigerant introduction / delivery piping) 19/24 Flange member 21 Second introduction piping (refrigerant introduction / delivery piping) 22 Second derivation piping (refrigerant introduction / delivery piping) 23 Third outlet pipe (refrigerant inlet / outlet pipe) 25/26 Door member 25b / 26b Through hole 27 Bolt (attaching means) 37 4 Rod-RFQ type linear accelerator

Claims (1)

[Scope of utility model registration request] 1. A cylindrical vacuum container, and an electrode assembly comprising four electrodes supported by a supporting member, the electrode assembly being arranged around the passage of accelerated particles passing through the vacuum container. A refrigerant passage through which a refrigerant passes is provided inside the electrode and / or the support member, and a plurality of refrigerant introduction / extensions connected to the refrigerant passage and extending outside the vacuum atmosphere are provided.
In a high-frequency quadrupole linear accelerator having a lead-out pipe, the predetermined portions of the plurality of refrigerant introduction / lead-out pipes are connected by a flange member, and a vacuum atmosphere is provided in an opening of the vacuum container. A door member that is openable and closable to separate the side from the atmosphere side is provided, and the door member is provided with a through hole that is smaller than the flange member that allows the plurality of refrigerant introduction / outlet pipes to pass therethrough. A high frequency quadrupole linear accelerator, wherein the flange member is attached to the door member by an attaching means so as to close the through hole.