US20150270093A1 - Plasma Arc Chamber - Google Patents
Plasma Arc Chamber Download PDFInfo
- Publication number
- US20150270093A1 US20150270093A1 US14/222,147 US201414222147A US2015270093A1 US 20150270093 A1 US20150270093 A1 US 20150270093A1 US 201414222147 A US201414222147 A US 201414222147A US 2015270093 A1 US2015270093 A1 US 2015270093A1
- Authority
- US
- United States
- Prior art keywords
- walls
- base
- liner
- opening
- arc chamber
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
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Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/02—Details
- H01J37/04—Arrangements of electrodes and associated parts for generating or controlling the discharge, e.g. electron-optical arrangement, ion-optical arrangement
- H01J37/08—Ion sources; Ion guns
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05H—PLASMA TECHNIQUE; PRODUCTION OF ACCELERATED ELECTRICALLY-CHARGED PARTICLES OR OF NEUTRONS; PRODUCTION OR ACCELERATION OF NEUTRAL MOLECULAR OR ATOMIC BEAMS
- H05H1/00—Generating plasma; Handling plasma
- H05H1/24—Generating plasma
- H05H1/26—Plasma torches
- H05H1/32—Plasma torches using an arc
- H05H1/34—Details, e.g. electrodes, nozzles
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/30—Electron-beam or ion-beam tubes for localised treatment of objects
- H01J37/317—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation
- H01J37/3171—Electron-beam or ion-beam tubes for localised treatment of objects for changing properties of the objects or for applying thin layers thereon, e.g. for ion implantation for ion implantation
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
- H01J2237/06—Sources
- H01J2237/061—Construction
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J2237/00—Discharge tubes exposing object to beam, e.g. for analysis treatment, etching, imaging
- H01J2237/16—Vessels
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01J—ELECTRIC DISCHARGE TUBES OR DISCHARGE LAMPS
- H01J37/00—Discharge tubes with provision for introducing objects or material to be exposed to the discharge, e.g. for the purpose of examination or processing thereof
- H01J37/32—Gas-filled discharge tubes
- H01J37/32431—Constructional details of the reactor
- H01J37/32458—Vessel
- H01J37/32467—Material
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T29/00—Metal working
- Y10T29/49—Method of mechanical manufacture
- Y10T29/49002—Electrical device making
Definitions
- This invention relates to a plasma arc chamber. More, particularly, this invention relates to a plasma arc chamber for an ion source assembly. Still more particularly, this invention relates to a plasma arc chamber for an ion source typically used in ion implanters.
- ion implanters are widely used to diffuse or implant positive ions onto regions of a semi-conductor wafer. These ion implanters use an ion source that generates an ion beam used to implant the semi-conductor wafers.
- the ion implanters employ an arc chamber to generate the ion beam.
- the arc chamber has been formed, in part, of a one-piece housing of box shape with a pair of openings at one end for a filament.
- a removable cover with a liner on the underside is provided on the housing to close the arc chamber and the liner and the cover provided with aligned central slits that function as an arc slit for passage of an ion beam from the arc chamber.
- the one-piece housing of this type of arc chamber can be fabricated by machining a solid block whereby material is removed from the center of the block to create a pocket; the resulting pocket being formed by four surrounding walls and a bottom surface.
- this method of fabrication is limited by the materials that can be used for the block.
- porous tungsten is the material that is used for the block.
- the method of fabrication is time consuming, expensive and the material removed is not useable and is thereby scrapped.
- the arc chamber has a bottom plate and four side wall plates that are interlocked together to define an enclosure along with a removable cover and liner with central slits.
- typical issue that arise with this method of fabrication involve fitting of the plates relative to one another and the potential for movement between the plates causing leakage. Increased part counts also results in increased fabrication costs.
- the invention provides an arc plasma chamber that is comprised, in part, of a one piece base having four rigid walls defining a rectangular central opening.
- This one piece base is fabricated from 95.95% pure tungsten.
- the plasma arc chamber has a bottom plate secured to the four walls of the base to close one end of opening and a cover removably mounted on the four walls of the base to close an opposite end of the opening and having a first slit for passage of an ion beam therethrough.
- a liner is also provided on an underside of the cover and has a slit in alignment with the slit in the cover for passage of the ion beam therethrough.
- the plasma arc chamber also has liners disposed on the walls and bottom plate, as is conventional. That is, the arc plasma chamber has a bottom liner disposed on the bottom plate, a repeller side liner disposed against one end wall, a cathode side liner disposed against an opposite end wall and side liners disposed against the opposite side walls.
- FIG. 1 is a perspective view of a plasma arc chamber constructed in accordance with the invention
- FIG. 2 is an exploded perspective view of the plasma arc chamber of FIG. 1 ;
- FIG. 3 is a schematic view of the one piece base of the plasma arc chamber of FIG. 1 during fabrication in accordance with the invention.
- the plasma arc chamber 10 has a one piece base 11 , a bottom plate 12 and a cover 13 .
- the one piece base 11 has four rigid walls 14 , 15 , 16 , 17 defining a rectangular central opening.
- one end wall 14 of the base 11 is provided with a circular opening 18 surrounded by a stepped circular recess 19 for mounting of a cathode assembly (not shown) while the opposite end wall 15 is provided with a circular opening 20 for mounting of a repeller assembly (not shown)
- each side wall 16 , 17 of the base 11 is provided with a pair of spaced apart parallel ribs 21 that are longitudinally disposed inside the central opening.
- a peripheral shoulder 22 is provided about the upper ends, as viewed, of the four walls 14 - 17 .
- the base 11 is formed from a single block of material, i.e. a block of 95.95% pure tungsten. As illustrated, the block is of rectangular brick-like shape from which a core 23 is removed to form the base 11 . In accordance with the method of fabrication of the invention, Electric Discharge Machining (EDM) is used to machine out the core 23 . As indicated, the core 23 is of brick-like shape with a pair of parallel grooves 24 on two opposite sides to reflect the formation of the ribs 21 within the base 11 .
- EDM Electric Discharge Machining
- the end walls 14 , 15 are machined to form the openings 18 , 20 and stepped recess 19 and the peripheral shoulder 22 is machined into the top of the base 11 .
- the removed core 23 being made of 95.95% tungsten may be recycled for further use and need not be scrapped.
- the bottom plate 12 is of rectangular shape and has a peripheral lip 25 for butting against the four walls 14 - 17 of the base 11 as well as a recess 26 within the peripheral lip 25 .
- the recess 26 includes an X-shaped recess 27 to channel the gas inside the arc chamber whereby the gas is distributed equally within the arc chamber.
- the cover 13 is of rectangular shape with a central slit 28 for passage of an ion beam. As indicated, the cover 13 is provided with a notch 29 at each of four corners to receive a mounting bolt (not shown) by which the cover 13 is removably mounted on he base 11 to close the central opening of the base 11 . As indicated in FIG. 1 , the cover 13 overhangs the base 11 so that the notches 29 are outside the plane of the base 11 .
- the plasma arc chamber 10 is also provided with six liners to line the chamber.
- One liner 30 fits within the recess 26 of the bottom plate 12 and has pairs of notches 31 that receive the ribs 21 on the side walls of the base 11 such that the liner 30 slides on the ribs 21 when being fitted into place in the bottom plate 12 .
- a cathode side liner 32 fits against the end wall 14 and is sized to extend from the liner 30 to the peripheral shoulder 22 . As indicated, this liner 32 has an aperture 33 to be aligned with the opening 18 in the end wall 14 . This liner 32 is slid into place by sliding along the ribs 21 of the two adjacent side walls 16 , 17 of the base 11 .
- a repeller side liner 34 fits against the opposite end wall 15 and is sized to extend from the liner 30 to the peripheral shoulder 22 . As indicated, this liner 34 has an aperture 35 to be aligned with the opening 20 in the end wall 15 . This liner 34 is slid into place by sliding along the ribs 21 of the two adjacent side walls 16 , 17 of the base 11 .
- a pair of side wall liners 36 fit against the respective side walls 16 , 17 and each is sized to extend from the liner 30 to the peripheral shoulder 22 .
- each side liner 36 is sized to extend between the cathode side liner 32 and repeller side liner 34 .
- Each side liner 36 has pairs of notches 37 at the top edge and the bottom edge which are aligned with the notches 31 in the bottom plate liner 30 for the delivery of gas inside the arc chamber.
- the side liners 36 rest against the ribs 21 of the side walls 16 , 17 of the base 11 thereby leaving a gap where the gas can travel to the inside of the arc chamber.
- a liner 38 with a central slit 39 fits into the peripheral shoulder 22 in the top of the base 11 in a recessed manner and against the cover 13 with the slit 39 in alignment with the slit 28 of the cover 13 .
- the liners 30 , 32 , 34 , 36 and 38 fit together without gaps therebetween and present smooth continuous surfaces with the central opening of the base 11 .
- the bottom plate 12 and cover 13 of the plasma arc chamber 10 may also be made of 95.95% tungsten.
- the several liners 30 , 32 , 34 , 36 and 38 may also be made of 95.95% tungsten.
- the invention thus provides an arc chamber that can be fabricated of 95.95% pure tungsten.
- the invention also provides a method of fabricating a plasma arc chamber at a reduced cost with rigid side walls while allowing removed material to be reused.
- the invention also reduces the amount of waste material generated in the fabrication of an arc chamber.
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- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Plasma & Fusion (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Spectroscopy & Molecular Physics (AREA)
- Electron Sources, Ion Sources (AREA)
Abstract
Description
- This invention relates to a plasma arc chamber. More, particularly, this invention relates to a plasma arc chamber for an ion source assembly. Still more particularly, this invention relates to a plasma arc chamber for an ion source typically used in ion implanters.
- As is known, in the manufacture of semi-conductors, ion implanters are widely used to diffuse or implant positive ions onto regions of a semi-conductor wafer. These ion implanters use an ion source that generates an ion beam used to implant the semi-conductor wafers.
- Typically, the ion implanters employ an arc chamber to generate the ion beam. In some cases, such as described in U.S. Pat. No. 8,658,986, the arc chamber has been formed, in part, of a one-piece housing of box shape with a pair of openings at one end for a filament. In addition, a removable cover with a liner on the underside is provided on the housing to close the arc chamber and the liner and the cover provided with aligned central slits that function as an arc slit for passage of an ion beam from the arc chamber.
- As is known, the one-piece housing of this type of arc chamber can be fabricated by machining a solid block whereby material is removed from the center of the block to create a pocket; the resulting pocket being formed by four surrounding walls and a bottom surface. However, this method of fabrication is limited by the materials that can be used for the block. Typically, porous tungsten is the material that is used for the block. Further, the method of fabrication is time consuming, expensive and the material removed is not useable and is thereby scrapped.
- In other cases, it has been known to fabricate an arc chamber of individual plates. In this regard, the arc chamber has a bottom plate and four side wall plates that are interlocked together to define an enclosure along with a removable cover and liner with central slits. However, typical issue that arise with this method of fabrication involve fitting of the plates relative to one another and the potential for movement between the plates causing leakage. Increased part counts also results in increased fabrication costs.
- Accordingly, it is an object of the invention to reduce the cost of fabricating an arc chamber.
- It is another object of the invention to provide an arc chamber fabricated of 95.95% pure tungsten.
- It is another object of the invention to provide an arc chamber with rigid side walls.
- It is another object of the invention to fabricate an arc chamber while allowing removed material to be reused.
- It is another object of the invention to reduce the amount of waste material generated in the fabrication of an arc chamber.
- Briefly, the invention provides an arc plasma chamber that is comprised, in part, of a one piece base having four rigid walls defining a rectangular central opening. This one piece base is fabricated from 95.95% pure tungsten.
- In addition, the plasma arc chamber has a bottom plate secured to the four walls of the base to close one end of opening and a cover removably mounted on the four walls of the base to close an opposite end of the opening and having a first slit for passage of an ion beam therethrough. A liner is also provided on an underside of the cover and has a slit in alignment with the slit in the cover for passage of the ion beam therethrough.
- The plasma arc chamber also has liners disposed on the walls and bottom plate, as is conventional. That is, the arc plasma chamber has a bottom liner disposed on the bottom plate, a repeller side liner disposed against one end wall, a cathode side liner disposed against an opposite end wall and side liners disposed against the opposite side walls.
- These and other objects and advantages of the invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings wherein:
-
FIG. 1 is a perspective view of a plasma arc chamber constructed in accordance with the invention; -
FIG. 2 is an exploded perspective view of the plasma arc chamber ofFIG. 1 ; and -
FIG. 3 is a schematic view of the one piece base of the plasma arc chamber ofFIG. 1 during fabrication in accordance with the invention. - Referring to
FIG. 1 , theplasma arc chamber 10 has a onepiece base 11, abottom plate 12 and acover 13. - Referring to
FIGS. 2 and 3 , the onepiece base 11 has fourrigid walls - As illustrated, one
end wall 14 of thebase 11 is provided with acircular opening 18 surrounded by a steppedcircular recess 19 for mounting of a cathode assembly (not shown) while theopposite end wall 15 is provided with acircular opening 20 for mounting of a repeller assembly (not shown) - In addition, each
side wall base 11 is provided with a pair of spaced apartparallel ribs 21 that are longitudinally disposed inside the central opening. - A
peripheral shoulder 22 is provided about the upper ends, as viewed, of the four walls 14-17. - Referring to
FIG. 3 , thebase 11 is formed from a single block of material, i.e. a block of 95.95% pure tungsten. As illustrated, the block is of rectangular brick-like shape from which acore 23 is removed to form thebase 11. In accordance with the method of fabrication of the invention, Electric Discharge Machining (EDM) is used to machine out thecore 23. As indicated, thecore 23 is of brick-like shape with a pair ofparallel grooves 24 on two opposite sides to reflect the formation of theribs 21 within thebase 11. - After removal of the
core 23, theend walls openings peripheral shoulder 22 is machined into the top of thebase 11. - The removed
core 23 being made of 95.95% tungsten may be recycled for further use and need not be scrapped. - Referring to
FIG. 2 , thebottom plate 12 is of rectangular shape and has aperipheral lip 25 for butting against the four walls 14-17 of thebase 11 as well as arecess 26 within theperipheral lip 25. Therecess 26 includes anX-shaped recess 27 to channel the gas inside the arc chamber whereby the gas is distributed equally within the arc chamber. - The
cover 13 is of rectangular shape with acentral slit 28 for passage of an ion beam. As indicated, thecover 13 is provided with anotch 29 at each of four corners to receive a mounting bolt (not shown) by which thecover 13 is removably mounted on hebase 11 to close the central opening of thebase 11. As indicated inFIG. 1 , thecover 13 overhangs thebase 11 so that thenotches 29 are outside the plane of thebase 11. - The
plasma arc chamber 10 is also provided with six liners to line the chamber. - One
liner 30 fits within therecess 26 of thebottom plate 12 and has pairs ofnotches 31 that receive theribs 21 on the side walls of thebase 11 such that theliner 30 slides on theribs 21 when being fitted into place in thebottom plate 12. - A cathode side liner 32 fits against the
end wall 14 and is sized to extend from theliner 30 to theperipheral shoulder 22. As indicated, this liner 32 has an aperture 33 to be aligned with the opening 18 in theend wall 14. This liner 32 is slid into place by sliding along theribs 21 of the twoadjacent side walls base 11. - A
repeller side liner 34 fits against theopposite end wall 15 and is sized to extend from theliner 30 to theperipheral shoulder 22. As indicated, thisliner 34 has anaperture 35 to be aligned with the opening 20 in theend wall 15. Thisliner 34 is slid into place by sliding along theribs 21 of the twoadjacent side walls base 11. - A pair of
side wall liners 36 fit against therespective side walls liner 30 to theperipheral shoulder 22. In addition, eachside liner 36 is sized to extend between the cathode side liner 32 andrepeller side liner 34. - Each
side liner 36 has pairs ofnotches 37 at the top edge and the bottom edge which are aligned with thenotches 31 in thebottom plate liner 30 for the delivery of gas inside the arc chamber. Theside liners 36 rest against theribs 21 of theside walls base 11 thereby leaving a gap where the gas can travel to the inside of the arc chamber. - A
liner 38 with acentral slit 39 fits into theperipheral shoulder 22 in the top of thebase 11 in a recessed manner and against thecover 13 with theslit 39 in alignment with theslit 28 of thecover 13. - The
liners base 11. - The
bottom plate 12 andcover 13 of theplasma arc chamber 10 may also be made of 95.95% tungsten. Likewise, theseveral liners - The invention thus provides an arc chamber that can be fabricated of 95.95% pure tungsten.
- The invention also provides a method of fabricating a plasma arc chamber at a reduced cost with rigid side walls while allowing removed material to be reused.
- The invention also reduces the amount of waste material generated in the fabrication of an arc chamber.
Claims (10)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
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US14/222,147 US9159526B1 (en) | 2014-03-21 | 2014-03-21 | Plasma arc chamber |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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US14/222,147 US9159526B1 (en) | 2014-03-21 | 2014-03-21 | Plasma arc chamber |
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Publication Number | Publication Date |
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US20150270093A1 true US20150270093A1 (en) | 2015-09-24 |
US9159526B1 US9159526B1 (en) | 2015-10-13 |
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US14/222,147 Active 2034-05-16 US9159526B1 (en) | 2014-03-21 | 2014-03-21 | Plasma arc chamber |
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Cited By (2)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN112271145A (en) * | 2020-09-25 | 2021-01-26 | 华东光电集成器件研究所 | Bottom plate of ion source arc chamber of implanter |
JP2023025239A (en) * | 2019-03-18 | 2023-02-21 | 住友重機械イオンテクノロジー株式会社 | Ion generating device and ion implanting device |
Family Cites Families (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US5641375A (en) * | 1994-08-15 | 1997-06-24 | Applied Materials, Inc. | Plasma etching reactor with surface protection means against erosion of walls |
US8253334B2 (en) * | 2010-07-19 | 2012-08-28 | Ion Technology Solutions, Llc | Ion source |
US8658986B1 (en) * | 2012-10-11 | 2014-02-25 | Ion Technology Solutions, Llc | Ion source assembly |
-
2014
- 2014-03-21 US US14/222,147 patent/US9159526B1/en active Active
Cited By (3)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP2023025239A (en) * | 2019-03-18 | 2023-02-21 | 住友重機械イオンテクノロジー株式会社 | Ion generating device and ion implanting device |
JP7325597B2 (en) | 2019-03-18 | 2023-08-14 | 住友重機械イオンテクノロジー株式会社 | Ion generator and ion implanter |
CN112271145A (en) * | 2020-09-25 | 2021-01-26 | 华东光电集成器件研究所 | Bottom plate of ion source arc chamber of implanter |
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US9159526B1 (en) | 2015-10-13 |
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