JP4841983B2 - Plasma homogenization method and ion source apparatus in ion source apparatus - Google Patents

Description

  The present invention relates to a plasma homogenization method and an ion source device in an ion source device.

In general, in a ribbon beam type doping apparatus for FPE, hydrogen-diluted B ₂ H ₆ , PH _{3 and the} like are introduced into an ion source apparatus and ionized to be extracted as a ribbon beam from a beam extraction system. In this case, not only dopant ions (PH _X ⁺ , P ₂ H _X ⁺ , or BH _X ⁺ , B ₂ H _X ⁺ ) containing B and P, but also H _X ⁺ ions are simultaneously extracted.

  As described above, in the conventional doping apparatus, hydrogen ions generated in the ion source apparatus are included in the ribbon beam and are directly implanted into the glass substrate, although they are unnecessary. Hydrogen ions may unnecessarily heat the glass substrate (panel) or cause problems in the process. Therefore, the conventional ion source apparatus is operated under such operating conditions that the generation rate of hydrogen ions is as low as possible. However, the reduction of hydrogen ions due to operating conditions is up to about 70%.

  On the other hand, in Patent Document 1, a set of permanent magnet arrays in which the N pole and the S pole are opposed to each other in the plasma chamber of the ion source device are arranged so as to sandwich the antenna. It is disclosed that the production rate can be reduced. However, the N-pole and S-pole permanent magnet arrays generate a magnetic field (N → S) parallel to the ion beam extraction surface and orthogonal to the beam longitudinal direction in the ion source device. The beam longitudinal direction means the longitudinal direction in the cross-sectional shape of the ribbon beam, and generally means the horizontal direction. In any case, the magnetic field has a magnetic field gradient that becomes weaker as it approaches the ion beam extraction surface. Due to the uneven distribution of the plasma density, the uniformity in the longitudinal direction of the beam extracted from the plasma deteriorates.

Japanese Patent Laying-Open No. 2005-5197

An object of the present invention is to provide a plasma homogenization method and an ion source apparatus capable of reducing hydrogen ions (H _X ⁺ ) in an ion beam and generating an ion beam having a uniform current distribution and a high dopant ratio. is there.

  The plasma uniform method according to the present invention includes a plasma chamber having an ion beam extraction surface, a supply unit for supplying an ion source gas into the plasma chamber, and a first chamber parallel to the ion beam extraction surface in the plasma chamber. A plurality of antennas for generating a high-frequency electric field in the plasma chamber by electric power supplied from a high-frequency power source and reacting with the ion source gas to generate plasma; and the plurality of antennas arranged in the first direction. A pair of antenna-facing magnets that assist in plasma generation by forming a high-concentration electron generation region by forming a magnetic field across the plurality of antennas so as to be opposed to each other, and the pair of antenna-facing magnets with respect to the plurality of antennas At least in a second direction in which the antenna-facing magnets are moved toward and away from each other, and in a third direction in which the antenna-facing magnet is moved closer to and away from the ion beam extraction surface Position adjusting means for moving in the direction of the plasma chamber, a plurality of permanent magnets for forming a cusp magnetic field for confining the generated plasma disposed around the wall surface of the plasma chamber, and the ion beam extraction surface. The present invention is applied to an ion source apparatus constituted by an ion beam extraction system including a plurality of electrodes for extracting an ion beam from plasma.

  The present plasma uniformization method is characterized in that the plasma loop in the plasma chamber is made uniform in the first direction by making the loop shape of the antenna long in the first direction.

  An ion source apparatus according to the present invention includes a plasma chamber having an ion beam extraction surface, a supply unit for supplying an ion source gas into the plasma chamber, and a first chamber parallel to the ion beam extraction surface in the plasma chamber. A plurality of antennas for generating a high-frequency electric field in the plasma chamber by electric power supplied from a high-frequency power source and reacting with the ion source gas to generate plasma; and the plurality of antennas arranged in the first direction. A pair of antenna-facing magnets that assist in plasma generation by forming a high-concentration electron generation region by forming a magnetic field across the plurality of antennas so as to be opposed to each other, and the pair of antenna-facing magnets At least one of a second direction in which the antenna-facing magnets are moved toward and away from each other and a third direction in which the antenna-facing magnet is moved toward and away from the ion beam extraction surface A position adjusting means for moving, a plurality of permanent magnets for forming a cusp magnetic field confining the generated plasma arranged around the wall surface of the plasma chamber, and a plasma generated by being provided on the ion beam extraction surface And an ion beam extraction system including a plurality of electrodes for extracting the ion beam.

  In the present ion source device, the loop shape of the antenna is long in the first direction.

  In both the plasma homogenization method and the ion source device, the loop shape of the antenna is preferably a racetrack shape or a long square shape.

  In both the plasma homogenization method and the ion source apparatus, it is preferable that an even number of the antennas are arranged in the first direction and the interval between the antennas is made smaller than the diameter in the longitudinal direction of the antennas.

  In both of the plasma homogenization method and the ion source device, the pair of antenna facing magnets have the same length in the first direction and opposite magnetic poles face each other, and the pair of antenna facing magnets are It is preferable to arrange at least two sets of the plasma chambers connected in series in the first direction so that the magnetic poles are reversed in the vicinity of the center in the first direction in the plasma chamber.

  In any of the plasma homogenization method and the ion source apparatus, the length of the at least two sets of antenna facing magnets connected in series in the first direction with respect to the first direction is the extraction slit in the ion beam extraction system. Is preferably greater than the length in the first direction.

  In both of the plasma homogenization method and the ion source device, the plurality of permanent magnets that form the cusp magnetic field are formed on the walls other than the region close to the ion beam extraction system among the walls forming the plasma chamber. It is preferable that they are arranged at intervals.

  In any of the plasma homogenization method and the ion source device, it is preferable that the position adjusting means can move the antenna facing magnet to the vicinity of the base of the antenna.

  In both of the plasma homogenization method and the ion source apparatus, the antenna facing magnet is overlapped in the third direction with the opposing yoke facing the antenna and one magnetic pole in close contact with the opposing yoke. A plurality of permanent magnets are arranged in a magnet case, and the size of the counter yoke in the third direction and the size of the stacked permanent magnets in the third direction are It is preferable that they are configured to be equal.

  In both of the plasma homogenization method and the ion source apparatus, out of the plurality of permanent magnets, the outer permanent magnets in the third direction are made longer in the second direction than the inner permanent magnets. Is preferred.

  In both of the plasma homogenization method and the ion source device, it is preferable to provide a plurality of water-cooled tubes in the magnet case to prevent the magnetic field from the antenna-facing magnet from being lowered by heat from the plasma.

  In both of the plasma homogenization method and the ion source device, the plurality of water cooling tubes include two water cooling tubes provided on both sides of the opposing yoke and one water cooling tube provided in the center of the back surface of the magnet case. It preferably consists of a tube.

  According to the present invention, there is also provided a doping apparatus including any one of the above ion source devices.

  According to the present invention, it is possible to generate plasma with a low hydrogen ratio and a uniform density in the longitudinal direction of the beam by improving the shape and arrangement of the antenna and the arrangement of at least two antenna facing magnets. An ion beam having uniform uniformity with respect to the longitudinal direction of the beam can be generated.

  An embodiment of an ion source device according to the present invention will be described with reference to FIG. FIG. 1A is a longitudinal sectional view of the ion source device viewed from the lateral direction, and FIG. 1B is an enlarged sectional view of a part (antenna-facing magnet) of FIG. It is.

  In FIG. 1A, the ion source device 1 has a box-shaped vacuum plasma chamber 10. The front surface side of the vacuum plasma chamber 10, that is, the right surface in the figure is an ion beam extraction surface. Although described in detail later, for the sake of convenience, the direction parallel to the ion beam extraction surface and perpendicular to the drawing is referred to as a first direction, the vertical direction in the drawing is the second direction, and the horizontal direction in the drawing is the third direction. Called the direction.

  The ion source device 1 includes an even number of antenna devices 20. As will be described in detail later, only one antenna device 20 is illustrated in FIG. 1A because it is installed side by side in the first direction. The antenna device 20 includes an RF exciter 21 installed on the back side of the vacuum plasma chamber 10 and an antenna 22 arranged in the vacuum plasma chamber 10. The RF exciter 21 supplies high frequency power to the antenna 22 to excite plasma. The RF exciter 21 is combined with a gas introduction unit 25 for introducing a gas corresponding to the ion species of the ion beam to be generated into the vacuum plasma chamber 10. The gas introduction part 25 has a gas introduction port 25 a around the rod of the antenna 22.

  In the vacuum plasma chamber 10, a pair of antenna facing magnets 30 </ b> A and 30 </ b> B are disposed facing each other with the antenna 22 interposed therebetween. These antenna facing magnets 30A and 30B have the same length in the first direction, and are respectively driven in the second direction, that is, the vertical direction and the third direction in FIG. Although it is made movable in the left-right direction of (a), details will be described later. A gas diffusion plate 40 is provided between the antenna facing magnets 30 </ b> A and 30 </ b> B and the inner wall on the back side of the vacuum plasma chamber 10. The gas diffusion plate 40 is for uniformly diffusing the gas introduced from the plurality of gas inlets 25 a into the vacuum plasma chamber 10.

  A beam extraction system 50 is provided on the front side of the vacuum plasma chamber 10, that is, on the ion beam extraction surface side. The beam extraction system 50 includes various electrodes described later and a shutter 51 that opens and closes in a door manner. The shutter 51 is used when changing the dose amount.

  In addition to the above, the ion source device 1 includes, for example, a vacuum exhaust device (not shown) for evacuating the vacuum plasma chamber 10.

  With reference to FIGS. 2-4, the arrangement | positioning form of the some antenna apparatus 20 in the ion source apparatus 1 shown to Fig.1 (a), the structure and arrangement | positioning form of antenna opposing magnet 30A, 30B, and the relationship between both are demonstrated. To do. 2 to 4 are diagrams schematically showing only the configuration of the main part in order to facilitate understanding of the structure of the ion source device 1 shown in FIG. In particular, FIG. 2 is a cross-sectional view of the ion source device 1 viewed from above, and FIG. 3 is a vertical cross-sectional view of the ion source device 1 viewed from the same horizontal direction as FIG. 2 and 3 respectively show X, Y, and Z as the first, second, and third directions defined in FIG. 4A and 4B are longitudinal sectional views of the ion source device 1 as viewed from the front side.

  In the present embodiment, as the even number of antennas, four antennas 22-1 to 22-4 are arranged in a first direction parallel to the ion beam extraction surface. In particular, each antenna has a loop shape of two turns and a long race track shape in the first direction, and the distance between each antenna is small. The antenna interval is preferably not more than twice the loop diameter (outer diameter in the third direction) of the antenna. Such an arrangement is for suppressing plasma non-uniformity between the antennas, and the loop shape of the antenna may be a rectangular shape that is long in the first direction.

  Here, the antenna facing magnets are composed of two pairs of antenna facing magnets 30A-1 and 30B-1 and 30A-2 and 30B-2 which are opposed to different magnetic poles. These antenna facing magnets have the same length in the first direction. In particular, the antenna facing magnet 30A-1 with the north pole facing the antenna side and the antenna facing magnet 30A-2 with the south pole facing the antenna side are vacuum. In the plasma chamber 10, the magnetic poles are reversed and connected and arranged at approximately the center position in the first direction. Conversely, the antenna-facing magnet 30B-1 with the S pole facing the antenna and the antenna-facing magnet 30B-2 with the N-pole facing the antenna have magnetic poles at substantially the center position in the first direction in the vacuum plasma chamber 10. They are connected and arranged so that they are reversed and aligned. Further, the antennas 22-1 and 22-2 are sandwiched between the antenna facing magnets 30A-1 and 30B-1, and the antennas 22-3 and 22-4 are disposed between the antenna facing magnets 30A-2 and 30B-2. To be sandwiched between. That is, the magnetic pole reversal portions of the two sets of antenna facing magnets are located at corresponding positions between the antennas 22-2 and 22-3.

  The antenna facing magnets 30A-1 and 30A-2 are integrally movable in a second direction and a third direction by a driving mechanism (not shown), and the antenna facing magnets 30B-1 and 30B-2 are also integrally formed. In addition, it is movable in the second direction and the third direction. However, in the movement in the second direction, the antenna facing magnets 30A-1 and 30A-2 and the antenna facing magnets 30B-1 and 30B-2 approach and move away from each other as shown by the solid line and the alternate long and short dash line in FIG. It ’s a good fit. On the other hand, the movement in the third direction is such that all four antennas integrally approach and separate from the ion beam extraction surface as indicated by the solid line and the alternate long and short dash line in FIG. Note that the movement in the third direction is movable to the vicinity of the base of each antenna as far as the back side of the vacuum plasma chamber 10 is concerned.

  In this way, the two sets of antenna facing magnets 30A-1, 30B-1, and 30A-2, 30B-2 are connected to an ion beam extraction system (described later) installed on the front side of the vacuum plasma chamber 10. The distance between the antenna facing magnets 30A-1 and 30B-1 and the distance between the antenna facing magnets 30A-2 and 30B-2 can be integrally adjusted. Such a position adjusting mechanism can be realized by a well-known technique, for example, a position adjusting mechanism disclosed in Patent Document 1, and thus detailed description thereof is omitted here.

  Returning to FIG. 1B, one of the antenna facing magnets will be described. FIG. 1B is an enlarged view of the antenna facing magnet 30B shown in FIG. 1A, and will be described below as the antenna facing magnet 30B-1 shown in FIGS. The remaining antenna facing magnets have the same structure. Here, the antenna facing magnet 30B-1 has a surface facing the antenna 22 and extends in the first direction, and is opposite to the facing surface of the facing yoke 31B-1. A plurality of (here, three) permanent magnets 32B-1, 33B-1, and 34B-1 stacked in the third direction with one magnetic pole (here, the S pole) closely attached to the surface of It has a case 35B-1 that is housed. The size of the counter yoke 31B-1 in the third direction is equal to the size of the three permanent magnets 32B-1, 33B-1, and 34B-1 stacked in the third direction in the third direction. On the other hand, the permanent magnets 32B-1, 33B-1, and 34B-1 extend in the first direction and have the same length in the first direction, but have different sizes in the second direction. That is, the size in the second direction of the permanent magnet 33B-1 that is the inner side with respect to the third direction is smaller than the size in the second direction of the permanent magnets 32B-1 and 34B-1 that is the outer side here. I have to. By doing in this way, the magnetic field which acts on an antenna can be made uniform, and plasma generation can be made uniform.

  The case 35B-1 is made of metal, for example, stainless steel or aluminum. Inside the case 35B-1, both sides of the opposing yoke 31B-1 (both sides in the third direction) and the opposite side (rear surface) of the opposing yoke 31B-1 A total of three cooling water pipes 36 </ b> B- 1 are built in the central part of the side). These three cooling water tubes prevent the magnetic field from the antenna facing magnet 30B-1 from being lowered by the heat from the plasma. Although not shown, each cooling water pipe is connected to a cooling water circulation system provided outside the vacuum plasma chamber 10 through a flexible pipe covered with a heat resistant material. This pipe may be built in an arm 61 (see FIGS. 2 and 3) for holding and moving the antenna facing magnet.

  2 and 3, among the walls forming the vacuum plasma chamber 10, the five walls excluding the wall on the ion beam extraction system side except for the region close to the ion beam extraction system are fixed. A plurality of permanent magnets 11 are provided at intervals. These permanent magnets 11 are for forming a cusp magnetic field to perform plasma confinement. Therefore, each permanent magnet directs magnetic poles into the vacuum plasma chamber 10 and magnetic poles of adjacent permanent magnets are different from each other. Be placed. 2 and 3 show the permanent magnet 11 exposed in the vacuum plasma chamber 10, but each permanent magnet has a groove provided on the outer wall side of the vacuum plasma chamber 10, as shown in FIG. It is preferable that the vacuum plasma chamber 10 is not exposed. In FIG. 1A, only the groove is shown, and the cusp magnetic field forming permanent magnet 11 is not shown.

  Next, the ion beam extraction system 50 will be described. The ion beam extraction system 50 includes a plasma electrode 51 and an extraction electrode 52 provided in this order from the vacuum plasma chamber 10 side, followed by a suppression electrode 54 and a ground electrode 55 via an insulator 53. Each electrode is formed with a slit that defines the cross-sectional shape of the extracted ion beam. In this embodiment, since the cross-sectional shape is drawn out as an ion beam having a horizontally long ribbon shape, the slits formed in each electrode also have a large size in the first direction, as is apparent from FIGS. The size in the second direction is small. In addition, as is apparent from FIG. 2, the size of the slit formed in each electrode in the first direction is smaller than the size of the two sets of antenna facing magnets in the first direction.

  The ion source apparatus 1 is installed so that an ion beam extraction system 50 communicates with a processing chamber of a doping apparatus.

  Then, the effect | action of this ion source apparatus 1 is demonstrated.

An ionizing gas such as B ₂ H ₆ or PH ₃ is introduced into the vacuum plasma chamber 10 in a vacuum state from the gas inlet 25a.

  High frequency power is supplied to the antennas 22-1 to 22-4 from the RF exciters 21-1 to 21-4.

  Then, an induction electric field is formed around the antenna by the high frequency power supplied to the antennas 22-1 to 22-4.

  The gas introduced into the vacuum plasma chamber 10 is ionized by an induction electric field to become plasma. The generated plasma is confined in the vacuum plasma chamber 10 by a cusp magnetic field generated by a plurality of permanent magnets 11.

  By applying a predetermined potential to each electrode of the ion beam extraction system, the ion beam is extracted from the plasma through the slit.

In the ion beam generation process as described above, for example, the N and S poles facing each other in the pair of antenna facing magnets 30A-1 and 30B-1 are parallel to the ion beam extraction surface, that is, the surface of the ion beam extraction system 50. A magnetic field (N → S) perpendicular to the direction of 1 is generated. When this magnetic field is generated in the vicinity of an antenna where neutral gas is ionized, low-energy electrons are trapped in this magnetic field to form a high-concentration low-energy electron generation region, and B ₂ H _X ^{+ having} a low ionization potential. The ionization of PH _X ^{+ and the} like is promoted as compared with the ionization of H ₂ , so that the ratio of H _X ⁺ ions in the plasma becomes relatively low, and an ion beam with a low hydrogen ratio is extracted.

  By reducing hydrogen ions in the ion beam and improving the dopant fraction, the temperature of the glass substrate during ion implantation is lowered, and the number of cooling operations can be reduced. This shortens the injection time and improves the throughput.

  On the other hand, the magnetic field strength by the antenna facing magnet decreases as the distance from the magnet center increases. That is, a magnetic field gradient is generated in a direction away from the magnet center. When this magnetic field gradient occurs, the plasma drifts in a direction perpendicular to the direction of the magnetic field and the direction of the gradient, that is, in the first direction. For this reason, if there is one set of N-pole and S-pole antenna facing magnets, the magnetic field (N → S) is also uniform in the first direction, so the longitudinal direction of the ion beam extracted from the plasma (ribbon shape) The uniformity in the longitudinal direction of the beam cross-sectional shape (hereinafter referred to as the beam longitudinal direction) is deteriorated.

  In addition, because of the sheath voltage generated in the vicinity of the antenna and the extraction electrode, ions and electrons in the plasma are drifted in one direction in the longitudinal direction of the beam, that is, in the first direction (the electric field E and the magnetic field B are not 0, When the particles intersect at a certain angle, the charged particles undergo a drift that moves in a direction perpendicular to both the electric and magnetic fields), and the plasma density is unevenly distributed in the longitudinal direction of the beam, and the ion beam extracted from the plasma The uniformity in the longitudinal direction of the beam deteriorates.

  On the other hand, in this embodiment, one set of N-pole and S-pole antenna facing magnets and one set of S-pole and N-pole antenna facing magnets whose magnetic fields are opposite to each other are provided in the vacuum plasma chamber 10. It arrange | positions in series so that it may invert in the center part vicinity (center of a beam longitudinal direction) of a 1st direction. In this way, the plasma drift and E × B drift due to the magnetic field gradient are canceled out and the beam is in the reverse direction at the center in the longitudinal direction of the beam. The beam is pulled out.

  For reference, FIG. 5 shows an example of the measurement result of the dopant fraction profile, and FIG. 6 shows an example of the measurement result of the beam profile. It can be understood that both the dopant fraction and the beam uniformity in the beam profile are uniform with respect to the beam longitudinal direction.

  Other main effects of the ion source device according to the present embodiment are as follows.

  By arranging an even number of antennas at small intervals and making the loop shape long in the antenna arrangement direction (first direction), the plasma density in the first direction in the vacuum plasma chamber can be made uniform. it can.

  In addition, at least two sets of antenna facing magnets are arranged in series by reversing the magnetic field direction of the antenna facing magnet, and the length of the antenna facing magnet in the first direction is made larger than the slit length in the ion beam extraction system, The plasma density can be leveled by reducing the plasma bias in the first direction in the vacuum plasma chamber. In addition, each antenna facing magnet is composed of a plurality of permanent magnets stacked in the third direction, and the magnetic field acting on the antenna such that the size in the second direction of these permanent magnets is smaller on the inside than on the outside. Since plasma is uniform, plasma generation can be made uniform.

Since the antenna facing magnet can be moved to the vicinity of the base of the antenna, the antenna can be arranged so that the central magnetic field of the antenna facing magnet passes through the base of the antenna. Since the induced voltage difference due to RF is large between the base portions of the antenna, plasma is likely to be generated, and the plasma density is increased, so that retention of low energy electrons in this portion can be enhanced.

  As described above, according to the ion source device of the present invention, the hydrogen ratio is low and the density is uniform in the longitudinal direction of the beam by improving the shape and arrangement of the antenna and the arrangement of the two antenna facing magnets. Can be generated, and an ion beam having uniform uniformity in the longitudinal direction of the beam can be extracted.

  The ion source device according to the present invention is not limited to the above embodiment, and for example, the following modifications are possible.

  The antenna facing magnets are arranged in one-to-one correspondence with the number of antennas, and the magnetic field applied to the antennas is arranged alternately for each antenna.

  Two sets of antenna facing magnets can be moved only in one of the second direction and the third direction.

FIG. 1A is a longitudinal sectional view of an ion source device according to the present invention as seen from the lateral direction, and FIG. 1B is an enlarged cross section of a part (antenna facing magnet) of FIG. FIG. FIG. 2 is a diagram schematically showing only the configuration of the main part in order to facilitate understanding of the structure of the ion source device shown in FIG. 1 (a). The ion source device is viewed from above. FIG. FIG. 3 is a diagram schematically showing only the configuration of the main part in order to facilitate understanding of the structure of the ion source device shown in FIG. It is the longitudinal cross-sectional view seen from the same horizontal direction as). 4 (a) and 4 (b) are diagrams schematically showing only the configuration of the main part in order to facilitate understanding of the structure of the ion source device shown in FIG. 1 (a). It is the longitudinal cross-sectional view which looked at the ion source device from the front side. FIG. 5 shows an example of the measurement result of the dopant fraction profile. FIG. 6 shows an example of the measurement result of the beam profile.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Ion source apparatus 10 Vacuum plasma chamber 11 Permanent magnet 20 Antenna apparatus 21, 211-1 to 21-4 RF exciter 22, 222-1 to 22-4 Antenna 30A, 30B, 30A-1, 30B-1, 30A-2 , 30B-2 Antenna facing magnet 40 Gas diffusion plate 50 Ion beam extraction system 51 Shutter

Claims (16)

A plasma chamber having an ion beam extraction surface, a supply unit for supplying an ion source gas into the plasma chamber, and a high frequency power source arranged in a first direction parallel to the ion beam extraction surface in the plasma chamber A plurality of antennas for generating a high-frequency electric field in the plasma chamber by electric power and reacting with the ion source gas to generate plasma, and being opposed to each other so as to sandwich the plurality of antennas arranged in the first direction, A pair of antenna facing magnets that assists plasma generation by forming a high concentration electron generation region by forming a magnetic field across the plurality of antennas, and the pair of antenna facing magnets close to each other Position adjusting means for moving in at least one of a second direction for separating and a third direction for approaching and separating from the ion beam extraction surface; A plurality of permanent magnets that are arranged around the wall portion of the plasma chamber and that form a cusp magnetic field that confines the generated plasma, and a plurality of ion magnets that are provided on the ion beam extraction surface for extracting the ion beam from the generated plasma. In a plasma homogenization method in an ion source device constituted by an ion beam extraction system comprising electrodes of
By making the loop shape of the antenna long in the first direction which is the arrangement direction of the antenna , the plasma density in the plasma chamber is made uniform with respect to the first direction, and
The pair of antenna facing magnets have an equal length with respect to the first direction and are opposed to different magnetic poles, and the pair of antenna facing magnets are arranged near the center of the plasma chamber in the first direction. At least two sets are arranged in series in the first direction so as to be inverted, thereby reducing the plasma bias in the first direction and equalizing the plasma density with respect to the first direction. A method for homogenizing plasma. 2. The plasma homogenization method according to claim 1, wherein the loop shape of the antenna is a racetrack shape or a rectangular shape that is long in the first direction, and a central magnetic field of the antenna facing magnet passes through the base of the loop shape antenna. A plasma homogenization method characterized by being arranged in such a manner.   3. The plasma homogenization method according to claim 1, wherein an even number of the antennas are arranged side by side in the first direction, and an antenna interval is set to be equal to or less than twice an antenna diameter. A plasma leveling method characterized by uniforming with respect to direction. In the plasma homogenization method according to any one of claims 1 to 3, a plurality of permanent magnets forming the cusp magnetic field, of the walls forming the plasma chamber, close to the ion beam extraction system A method for homogenizing plasma, characterized in that the plasma is arranged at intervals on a wall excluding the region. The plasma homogenization method according to any one of claims 1 to 4 , wherein the antenna facing magnet is movable to the vicinity of a base portion of the antenna. A plasma chamber having an ion beam extraction surface, a supply unit for supplying an ion source gas into the plasma chamber, and a high frequency power source arranged in a first direction parallel to the ion beam extraction surface in the plasma chamber A plurality of antennas for generating a high-frequency electric field in the plasma chamber by electric power and reacting with the ion source gas to generate plasma, and being opposed to each other so as to sandwich the plurality of antennas arranged in the first direction, A pair of antenna facing magnets that assists plasma generation by forming a high concentration electron generation region by forming a magnetic field across the plurality of antennas, and the pair of antenna facing magnets close to each other Position adjusting means for moving in at least one of a second direction for separating and a third direction for approaching and separating from the ion beam extraction surface; A plurality of permanent magnets that are arranged around the wall portion of the plasma chamber and that form a cusp magnetic field that confines the generated plasma, and a plurality of ion magnets that are provided on the ion beam extraction surface for extracting the ion beam from the generated plasma. in the ion source apparatus constructed by an ion beam extraction system consisting of the electrodes,
With a loop shape before Symbol antenna and elongated in the first direction, said pair of antenna opposing magnets different poles and having a length equal with respect to said first direction is to face, of the pair An ion source device , wherein at least two pairs of antenna facing magnets are connected in series in the first direction so that the magnetic poles are reversed in the vicinity of the center in the first direction in the plasma chamber . 7. The ion source device according to claim 6 , wherein the loop shape of the antenna is a racetrack shape or a long square shape. In the ion source device according to claim 6 or 7, wherein the antenna is an even number, the first being arranged in a direction, the ion source device being characterized in that the antenna spacing than 2 times the antenna diameter. 9. The ion source device according to claim 6 , wherein lengths of at least two sets of antenna facing magnets connected in series in the first direction with respect to the first direction are the ion beam extraction. An ion source device, wherein the length of the extraction slit in the system is greater than the length in the first direction. The ion source device according to any one of claims 6 to 9 , wherein the plurality of permanent magnets forming the cusp magnetic field are regions close to the ion beam extraction system among walls forming the plasma chamber. An ion source device, characterized in that the ion source device is disposed at intervals on a wall excluding. In the ion source device according to any one of claims 6-10, wherein the position adjusting means includes an ion source and wherein the said antenna opposing magnets is movable to the vicinity of the base of the antenna. In the ion source device according to any one of claims 6-11, wherein the antenna opposing magnets, said third direction of one magnetic pole is brought into close contact with the opposing yoke and the counter yoke facing to the antenna A plurality of permanent magnets stacked in a magnet case, and the size of the counter yoke in the third direction and the third direction of the stacked permanent magnets. An ion source device characterized in that the size of the ion source device is equal. The ion source device according to claim 12 , wherein out of the plurality of permanent magnets, both outer permanent magnets are longer in the second direction than the inner permanent magnet in the third direction. Ion source device. In the ion source device according to claim 12 or 13, a plurality of cooling water pipe in the magnet case, the ion source device field from the antenna opposing magnet by heat from the plasma, characterized in that to prevent the decrease . 15. The ion source device according to claim 14 , wherein the plurality of water cooling tubes are composed of two water cooling tubes provided on both sides of the opposing yoke and one water cooling tube provided in the center of the back surface of the magnet case. An ion source device characterized by that. A doping apparatus comprising the ion source apparatus according to any one of claims 6 to 15 .

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