JP4303337B2 - Molecular ion enhanced ion source device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an ion source apparatus suitable for generating monovalent ions of polyatomic molecules and ion implantation thereof.
[0002]
[Prior art]
In a conventional ion source for ion implantation (typically, a PIG type or the like), electrons having a relatively high energy are collided in order to strip electrons from molecules. The energy of the electrons is not small compared to the binding energy of the molecule, and since it is confined to some extent, the same molecule will collide multiple times and the gas molecule will be decomposed into small molecules or single atoms. Probability is high. In the case of ionization of these molecules, the amount of extracted beam current is large, but the required monovalent polyatomic molecular ion component is very small.
[0003]
A conventional ion source for generating clusters is ionized by irradiating gasified polyatomic molecules (clusters) with electrons having relatively high energy. However, since there is no plasma confinement mechanism, the collision frequency between particles is low, and many molecules are not subjected to collision and are not ionized, or even if ionized, they are not subjected to further collision. Therefore, it is easy to keep the shape of the original molecule, and the necessary molecular ions occupy most of the ions. However, the amount of beam current obtained is extremely weak (nA order).
[0004]
[Problems to be solved by the invention]
The conventional ECR ion source has a very high electron temperature in the plasma due to efficient electron heating, and a very high plasma density due to a strong magnetic field. For this reason, it is mainly used for the production of multivalent ions, and there is no example mainly for the production of molecular ions.
[0005]
Accordingly, an object of the present invention is to provide a molecular ion enhanced ion source apparatus capable of generating large current ions.
[0006]
[Means for Solving the Problems]
According to the present invention, the cylindrical base frame is arranged and configured on the outer peripheral portion of the cylindrical plasma chamber, and is fixedly arranged on the outer peripheral surface of the cylindrical base frame in a direction parallel to the central axis of the base frame. A multipole permanent magnet device comprising a plurality of rod-like permanent magnets and a cylindrical yoke is provided to form a multipole magnetic field, and is at both ends of the multipole permanent magnet device and parallel to the central axis of the base frame. such directions provided end frame on both ends of, Configure the pair of mirror field by disposing the mirror magnet by the mirror coil or a plurality of rod-shaped permanent magnet on the outer peripheral side of the end portion frame, the pair A confinement magnetic field is formed in the plasma chamber inside the substrate frame by a mirror magnetic field and the multipole magnetic field, and an ion generating gas and microwave are introduced into the plasma chamber in the magnetic field. Plasma Chan A plasma with an elongated cross-sectional shape that intersects the central axis of the plasma chamber at right angles is generated by a confinement magnetic field in a direction that coincides with the central axis direction of the plasma chamber, and an ion beam is extracted by an extraction electrode provided on one end side of the plasma chamber The confinement magnetic field in the plasma chamber is configured so that the central axis of the mirror magnet coincides with the central axis of the multipolar permanent magnet device, and the direction of the pair of mirror magnetic fields generated by the mirror magnet is the central axis At least one connection to the side periphery of the triple structure of the plasma chamber, the substrate frame and the multipolar permanent magnet device for connection with the microwave introduction waveguide And connecting the waveguide, the connecting portion being positioned between the rod-shaped permanent magnets of the multipolar permanent magnet device, and the plasma chamber and the front As parallel long hole shape in the direction of the center axis of the base frame, the plasma from the radial direction of the connecting portion of the chamber so as to introduce the microwave, a vacuum vessel loaded with the ion source gas material in the solid state, a temperature controlled A molecule characterized in that plasma generation by ECR is performed by providing a supply port on one end on the central axis of the plasma chamber by indirectly heating the ion source gas substance by immersing it in a liquid and supplying it by gasification. An ion enhanced ion source device is provided.
[0008]
One end side or both end sides of the lead electrode side of the multipolar permanent magnet arrangement, arranged multipolar permanent magnet arrangement of the end portion between the inner circumferential side of the mirror magnets and the outer peripheral side of the end frame You may make it do.
[0009]
The end frame may be provided integrally with the base frame.
[0010]
Of the pair of mirror magnetic fields, the mirror magnet on the side opposite to the extraction electrode and the multipolar permanent magnet device each generate a confined magnetic field having a maximum magnetic flux density of 2 kilogauss or more.
[0011]
With the multipole permanent magnet device on the end side , the confined magnetic field in the plasma chamber can be configured so that the maximum magnetic flux density in the plasma chamber is 2 kilogauss or more.
[0012]
The microwave is preferably 2.45 (GHz).
[0014]
The microwave power is preferably 100 (W) at the maximum.
[0017]
Solid decaborane can be used as the ion source gas material.
[0018]
[Action]
According to the above configuration, polyatomic molecular ions can be efficiently generated. For ion implantation, when it is desired to implant a very shallow necessary atom, for example, low-energy boron (B), into a Si substrate, a molecular ion having a high current of 5 (keV) or less, such as decaborane (B ₁₀ H ₁₄ ). Ions etc. can be generated. For example, roughly one B ₁₀ H ₁₄ ⁺ ion at 5 (keV) corresponds to 10 B ⁺ ions at 500 (eV). B ₁₀ H ₁₄ ⁺ ions are extracted at 5 (keV), whereas B ⁺ ions are 500 (eV), so it is easy to extract, and since the charge is as low as 1/10 for one B atom, the repulsive force is small, so the wafer It will be easy to transport to.
[0019]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of a molecular ion enhanced ion source apparatus according to the present invention will be described below with reference to the drawings. FIG. 1 shows the configuration of the entire apparatus. In this embodiment, the ion generating gas is supplied to the ion source device 1 by immersing the solid loading vacuum chamber 31 loaded with the ion source gas material in a solid state in a temperature-controlled liquid in the thermostatic chamber 32. Thus, the ion source gas substance is indirectly heated and gasified. In the thermostat 32, the liquid is circulated by the pump 33, and the liquid is heated by the heater 35 provided in the insulating tube 34 for circulation. A gas for generating ions is introduced into the plasma chamber 10 from a supply port provided on one end side on the central axis of the plasma chamber 10 in the ion source device 1. A valve 37-1, a switching valve 38, and a gas flow rate adjustment valve 36 are provided in the pipe from the solid loading vacuum chamber 31 to the supply port.
[0020]
In this embodiment, a polyatomic molecular gas source 30 is further provided so that the gas from the solid loading vacuum chamber 31 can be switched by the switching valve 38 via the valve 37-2.
[0021]
The polyatomic gas for generating ions is introduced into the plasma chamber 10 from the direction of the mirror electromagnet 11. In particular, in the case of decaborane or the like that has not been gasified at room temperature, the decaborane is loaded in a solid state vacuum tank 31 in a solid state. It sublimates and is supplied into the plasma chamber 10. Decaborane, which is a solid with a relatively high vapor pressure and is important for temperature control of 100 degrees or less, is indirect using a liquid such as water with a large heat capacity as a medium, rather than loading a vacuum tank with a heater wound directly as in the past. Heating increases the temperature stability and simplifies temperature control.
[0022]
A microwave from a microwave power source 39 equipped with an RF oscillator is also introduced into the plasma chamber 10 from the radial direction.
[0023]
Although FIG. 1 shows an example in which the thermostatic chamber 32 is disposed in the high voltage section and the pump 33, the heater 35, etc. are disposed on the ground, the entire apparatus may be floated at a high pressure or may be grounded.
[0024]
FIG. 2 shows a schematic configuration of an ion implantation apparatus to which the present ion source apparatus is applied. Ions from the ion source device are introduced into the mass separator 43 through the acceleration section 41 and the extraction chamber 42, and necessary ion species are separated. The separated ions are irradiated to the wafer 47 in the ion implantation chamber 46 through the mass separation slit 44 and the beam control variable width slit 45. In FIG. 2, only one wafer 47 appears to be in the center of the ion implantation chamber 46, but in practice, a plurality of wafers 47 are rotatably arranged in the ion implantation chamber 46. It arrange | positions in the peripheral part of the disc 48 at intervals in the circumferential direction. The components from the acceleration section 41 to the ion implantation chamber 46 are well known and are not the main part of the present invention, so detailed description thereof will be omitted.
[0025]
Referring to FIGS. 3 and 4, this ion source device includes a pair of mirror electromagnets 11 and 12 arranged at intervals to create a mirror magnetic field outside a cylindrical plasma chamber 10, and a plasma chamber. 10 and a multipolar permanent magnet device 20 provided between the mirror electromagnets 11 and 12. Each of the mirror electromagnets 11 and 12 is realized by a solenoid coil. The strength of each magnetic field can be set independently as required. Each of the mirror electromagnets 11 and 12 may be composed of a plurality of rod-shaped permanent magnets having necessary set values.
[0026]
A connection portion 21 a having a waveguide portion is provided on the side surface of the plasma chamber 10, and the waveguide 13 is connected to introduce microwaves into the plasma chamber 10 from the radial direction. An RF window 22a is sandwiched between portions where the waveguide and the plasma chamber are connected. The RF window 22a transmits microwaves from the atmosphere into the plasma chamber 10, but maintains the vacuum in the plasma chamber 10. The position of the RF window 22a on the side surface of the plasma chamber 10 is less susceptible to plasma irradiation due to the magnetic field structure. Compared to the case where the RF window 22a is introduced from the plasma chamber axial direction as in an ECR ion source for a conventional ion implanter, There is an advantage that it is hard to get dirty. Since the RF window 22a becomes conductive when it becomes dirty, the microwave is cut off and the operation cannot be continued.
[0027]
In such an ion source device, a high magnetic field is formed in the plasma chamber 10 by the mirror electromagnets 11 and 12 and the multipolar permanent magnet device 20, and an appropriate amount of ion generating gas and 2.45 ( By introducing a microwave of (GHz), electrons are heated by ECR heating, plasma is generated, and an ion beam can be generated in the axial direction of the plasma chamber 10. When there is an 875 Gauss magnetic field for 2.45 (GHz) microwaves, electron ECR heating occurs.
[0028]
An ion extraction casing 40-1 is provided at the end of the mirror electromagnet 12, and an extraction electrode 40-2 and an anode electrode 40-3 are provided in the casing 40-1.
[0029]
Another function of the magnetic field described above is to effectively confine the plasma, resulting in increased ionization efficiency and reduced contamination of the RF window 22a. The plasma that tries to spread in the direction of the mirror electromagnet 11 and the multipolar permanent magnet device 20 is not drawn out as a beam, and is lost and uneconomical. Specifically, the maximum value of the magnetic field generated by the mirror electromagnet 11 and the multipolar permanent magnet device 20 needs to be at least 875 gauss or more in the plasma chamber 10 and is desirably 2 kilogauss or more. On the other hand, the magnetic field of the mirror electromagnet 12 is weakened to create a plasma escape path in that direction. Ions in the plasma are taken out of the plasma chamber 10 from the direction of the mirror electromagnet 12. The magnetic field generated by the mirror electromagnet 12 may be about several hundred gauss in the plasma chamber 10.
[0030]
Microwave power is reduced and the energy of electrons in the plasma is kept low. Although some of the high energy electrons are present due to ECR heating, if the ratio of the high energy electrons is small, the electrons are diluted, and on the average, the low energy electrons are dominant. Even if there are many electron collisions in one molecule, the energy of the electrons is kept low, so it is unlikely that two or more electrons will be separated from the same molecule, and as a result, a single molecular ion is generated. It is unlikely to be broken down into atomic ions. When ionizing decaborane molecules, if the magnetic field is the above value, the volume of the plasma chamber 10 is about 500 cc, and the degree of vacuum in the plasma chamber 10 is 1 × 10 ⁻⁴ Torr or less (high vacuum side), about 100 (W) Good. Since the confined magnetic field is effective, the plasma can be maintained sufficiently.
[0031]
As shown in detail in FIGS. 5 and 6, the multipole permanent magnet device 20 includes quadrupole permanent magnets 23 a to 23 d and a cylindrical yoke 24 provided on the outside thereof. In particular, in this example, each of the quadrupole permanent magnets 23a to 23d is configured by combining two rod-shaped magnets having a trapezoidal cross-sectional shape with the wide bottom surface facing outward, and further the quadrupole permanent magnet. 23a to 23d are combined with the base frame 26 in a ring shape. The base frame 26 is made of a nonmagnetic material such as aluminum. The magnetic poles of the four-pole permanent magnets 23a to 23d are arranged such that the magnetic poles facing each other with respect to the central axis direction of the plasma chamber 10 are the same, and the adjacent magnetic poles are opposite to each other in the circumferential direction. .
[0032]
The multipolar permanent magnet device 20 is formed by combining a plurality of rod-shaped magnets extending in the direction of the central axis of the plasma chamber 10 from both ends of the base frame 26 in addition to the above-described four-pole permanent magnets 23a to 23d. It has a set of multipolar permanent magnets 25-1 to 25-2. Speaking of the multipolar permanent magnet 25-1, here, 16 magnetic poles 25-1a to 25-1h are configured by combining 16 rod-shaped magnets in pairs. Among the eight magnetic poles 25-1a to 25-1h, the magnetic poles 25-1a to 25-1d corresponding to the four-pole permanent magnets 23a to 23d have the same magnetic pole direction as that of the four-pole permanent magnets 23a to 23d. Arranged to be the same. In addition, the magnetic poles 25-1f to 25-1h arranged between the magnetic poles 25-1a to 25-1d are arranged so that the magnetic poles are in the circumferential direction and opposite to each other. Similarly, in the multipolar permanent magnet 25-2, eight magnetic poles are formed. Cylindrical frames 27-1 and 27-2 made of a nonmagnetic material are provided outside the multipolar permanent magnets 25-1 to 25-2, respectively.
[0033]
Two sets of multipolar permanent magnets 25-1 and 25-2 are interposed between the mirror electromagnets 11 and 12 and the plasma chamber 10, and if there is a yoke, the mirror electromagnets 11 and 12 cause the plasma chamber. Since the magnetic field generated in the motor 10 becomes small, the yoke 24 combined with the quadrupole permanent magnets 23a to 23d is not provided. In any case, the permanent magnet used in the multipolar permanent magnet device 20 is one having a magnetization direction perpendicular to the magnetic pole surface and having residual magnetism of the same strength.
[0034]
The multipolar permanent magnets 25-1 to 25-2 are not indispensable and may be deleted. In this case, both ends (end frames) of the base frame 26 that are extended to form the multipolar permanent magnets 25-1 to 25-2 may be omitted. Further, the portions corresponding to the both end portions may be configured separately from the base frame 26. Furthermore, the inner side of the base frame 26 has a cylindrical shape, but the outer surface is flattened so that the quadrupole permanent magnets 23a to 23d and the multipolar permanent magnets 25-1 and 25-2 are easily bonded. ing. For this reason, the outer side of the base frame 26 has a polygonal shape.
[0035]
Note that four long holes 24 a to 24 d are provided on the side surface of the yoke 24 at intervals in the circumferential direction. This is because the waveguide connection described in FIG. 4 can be connected at four arbitrary locations. The base frame 26 is provided with the long holes 26a only at the portions corresponding to the long holes 24a. However, the base frame 26 has the same length as the long holes 26a at the portions corresponding to the long holes 24b to 24d according to the connection portions of the waveguide. A hole is provided. For this reason, not only the location corresponding to the long hole 24a in the base frame 26 but also the location corresponding to the long holes 24b to 24d are removed from the installation area of the four-pole permanent magnets 23a to 23d. And the location where the long hole is provided in the base frame 26 is the location corresponding to the polygonal corner, but when the long hole is provided, the corner is ground.
[0036]
Of course, long holes may be provided in advance in locations corresponding to the four long holes 24 a to 24 d of the yoke 24 in the base frame 26. In this case, the plasma chamber 10 is also provided with a long hole at a position corresponding to the long hole of the base frame 26, but a long hole to which the waveguide 13 is not connected in order to maintain the degree of vacuum in the plasma chamber 10. Needs to be closed with something like a lid.
[0037]
Returning to FIG. 3, a gas introduction pipe 29 is connected to the left end of the plasma chamber 10. The right end of the plasma chamber 10 is opened to serve as an ion beam outlet, and a guide tube (not shown) for guiding the ion beam to the irradiation unit is connected to the opening of the plasma chamber 10.
[0038]
In the ion source apparatus according to the present invention, fragile decaborane (B ₁₀ H ₁₄ ) molecules are ionized without breaking, and a high current beam can be extracted.
[0039]
The ion source gas is supplied in a gas state. A substance that is solid at room temperature is packed in a solid loading vacuum chamber 31 outside the ion source, and the solid loading vacuum chamber 31 is heated in a thermostatic chamber 32 to heat and gasify the target solid and supply it to the ion source. .
[0040]
A pair of mirror electromagnets 11 and 12 arranged at intervals in order to create a mirror magnetic field on the outside of the plasma chamber 10 and a multipole provided outside the plasma chamber 10 and between the mirror electromagnets 11 and 12. And a permanent magnet device 20. Since the magnetic field of the mirror electromagnet 11 and the multipolar permanent magnet device 20 is configured as a strong magnetic field structure, and the magnetic field of the mirror electromagnet 12 is configured as a weak magnetic field structure, the plasma is induced from the center of the plasma chamber toward the mirror electromagnet 12, and the like. Since the magnetic field is strong in the direction of, it can be confined efficiently. Specifically, in order to strengthen the confinement, it is desirable that the maximum value of the magnetic field of the mirror electromagnet 11 and the multipolar permanent magnet device 20 is about 2 kilogauss or more in the plasma chamber 10 if possible. The mirror electromagnet 12 is preferably about several hundred gauss.
[0041]
The beam is drawn out of the plasma chamber 10 through an anode slit in the core portion of the mirror electromagnet 12. The anode has a thin disk shape and has a through hole in the circular plane. There is an extraction electrode facing the anode outside the plasma chamber, and it has a through-hole almost the same shape as the anode. When a voltage is applied so that the anode is positive with respect to the extraction voltage, ions leaking from the plasma chamber are extracted through the two through holes.
[0042]
Although the above description is for decaborane, it is clear that it can be applied to other polyatomic molecules.
[0043]
According to the ion source device as described above, a confined magnetic field is formed in the plasma chamber 10 by the combination with the pair of mirror electromagnets 11 and 12.
[0044]
In this confinement magnetic field, as compared with the conventional microwave ion source device, the plasma electrons generated in the plasma chamber 10 are suppressed from being scattered in the radial direction of the plasma chamber 10, and the electron confinement time is reduced. By extending and heating the electrons by the ECR heating action, plasma is easily generated. In particular, the plasma can be sustained even when the degree of vacuum in the plasma chamber 10 is high. Then, such ions are efficiently suppressed from leaking in the radial direction of the plasma chamber 10, and adhesion to the inner wall of the plasma chamber 10 and the RF window is suppressed. This means that it is possible to suppress the microwave transmission efficiency from being lowered due to the adhesion of ions to the RF window 22a.
[0045]
Thus, when the ion confinement efficiency is improved, the amount of gas introduced into the plasma chamber 10 can be reduced, and the degree of contamination in the plasma chamber 10 can be reduced. Even if the introduced gas is a corrosive gas, it is possible to suppress the ions from adhering to the inner wall of the plasma chamber 10 and corroding the inner wall. This means that the lifetime of the ion source device is prolonged.
[0046]
In addition, by setting the multipolar permanent magnets in the region where the microwave is introduced to the quadrupole permanent magnets 23a to 23d, the interaction with the magnetic field by the pair of mirror electromagnets 11 and 12 causes the central axis of the plasma chamber 10 to move. An ion beam having an elongated cross-sectional shape intersecting at right angles can be generated. It is known that the cross-sectional shape of this ion beam changes according to the number of poles of the multipolar permanent magnet in the region where the microwave is introduced. Incidentally, in the case of 6 poles, the cross-sectional shape is substantially triangular, and in the case of 8 poles, it is substantially square. The multipole maximum magnetic field strength configured in the plasma chamber 10 is preferably a magnetic field of 2 kilogauss or more.
[0047]
The relationship between the pair of mirror electromagnets 11 and 12 and the yoke 24 will be described with reference to FIG. Since the multipolar permanent magnet combined with the mirror electromagnets 11 and 12 cannot create a magnetic field in the plasma chamber 10 unless it is inside the yoke 24, the yoke 24 can be formed by forming the quadrupole permanent magnets 23a to 23d using rod-shaped magnets. And a thin space between the plasma chamber 10 and the plasma chamber 10 can be accommodated. FIG. 7B shows an example of a magnetic field using a quadrupole permanent magnet.
[0048]
Next, the principle of ion confinement action by a magnetic field of a quadrupole permanent magnet will be described with reference to FIG. In FIG. 8, the magnetic field lines between the quadrupole permanent magnets are symbolically shown one by one. Also, the broken line indicates the isomagnetic field strength range of the absolute value | B | of the magnetic field. The closer to the center, the closer the magnetic field strength is to an isotropic shape, but the more the magnetic field becomes isotropic, the closer it is to the magnetic pole. It ’s not right. The charged particles existing in such a magnetic field try to move to the magnetic pole side while moving in a spiral around the magnetic field lines. In other words, the charged particles tend to move toward the direction where the center of rotation becomes stronger. Such charged particles are also subject to a rebound action that moves in the opposite direction as the magnetic field strength increases as it approaches the magnetic pole. The degree of the rebound is determined by the initial motion direction, and the rebound is more easily as the strength ratio of the magnetic field (the ratio between the minimum value of the valley of the curve and the peak value in the case of quoting FIG. 7B) is larger. By such a principle, an ion confinement action in which the residence time of ions becomes long occurs. On the other hand, the RF window 22a is in a position that is parallel to the magnetic field lines, and ions are difficult to move in a direction perpendicular to the magnetic field lines, which is also one of the causes that the attachment of ions to the RF window 22a is difficult to occur.
[0049]
By the way, the reason why the frequency of the microwave is set to 2.45 (GHz) is that this frequency generator is used in household electric appliances such as a microwave oven and is provided at the lowest price. If it is not necessary to consider this, another frequency may be used.
[0050]
The present invention has been described with respect to the case of a four-pole permanent magnet, but it goes without saying that the number of magnetic poles is not limited to four.
[0051]
【The invention's effect】
According to the present invention, the following effects can be obtained.
[0052]
Since a plasma with low electron energy is generated in an efficient confined magnetic field, relatively high current decaborane ions can be selectively generated.
[0053]
Since microwaves are introduced from the radial direction of the plasma chamber, the rate at which the RF window becomes dirty decreases, and the maintenance period of the ion source becomes longer.
[0054]
The vacuum chamber in which decaborane is loaded is heated through the liquid in the thermostatic chamber, and stable temperature control is possible as compared with the case where it is directly heated by the heater.
[Brief description of the drawings]
FIG. 1 is a diagram showing an embodiment of a molecular ion enhanced ion source device according to the present invention.
FIG. 2 is a diagram showing a configuration of an ion implantation apparatus to which the present invention is applied.
FIG. 3 is a longitudinal sectional view showing an ion source device of the molecular ion enhanced ion source device according to the present invention.
4 is a cross-sectional view taken along line AA ′ of FIG.
5 is a diagram showing the multipolar permanent magnet device shown in FIG. 3, in which FIG. (A) is a partially sectional side view, and (b) is a sectional view taken along line BB ′ of FIG. FIG. 7C is a sectional view taken along line CC ′ of FIG.
6 is a side view and a cross-sectional view of the yoke, the base frame and the frame shown in FIG. 5. FIG.
7 is a diagram for explaining the mirror electromagnet and the yoke shown in FIG. 3. FIG. 7 (a) is a longitudinal sectional view, and FIG. 7 (b) shows an example of a magnetic field when a quadrupole permanent magnet is used. It is a figure.
8 is a diagram for explaining the operation of the quadrupole permanent magnet shown in FIG. 4; FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Ion source apparatus 10 Plasma chamber 11, 12 Mirror electromagnet 13 Waveguide 20 Multipole permanent magnet apparatus 21a Connection part 22a RF window 23a-23d 4 pole permanent magnet 24 Yoke 25-1, 25-2 Multipole permanent magnet 26 Base Frame 27-1, 27-2 Frame 29 Gas introduction pipe 41 Acceleration section 42 Drawer chamber 43 Mass separator 44 Mass separation slit 45 Beam control variable width slit 46 Ion implantation chamber 47 Wafer 48 Rotating disk

Claims (8)

A plurality of rod-like permanent magnets having a cylindrical base frame arranged on the outer periphery of a cylindrical plasma chamber and fixedly arranged on the outer peripheral surface of the cylindrical base frame in a direction parallel to the central axis of the base frame And a multipole permanent magnet device with a cylindrical yoke to form a multipole magnetic field,
End frames are provided on both ends of the multipolar permanent magnet device and on both ends in a direction parallel to the central axis of the base frame,
Configure the pair of mirror field by disposing the mirror magnet by the mirror coil or a plurality of rod-shaped permanent magnet on the outer peripheral side of the end part frame,
The pair of mirror magnetic fields and the multipole magnetic field form a confined magnetic field in the plasma chamber inside the substrate frame, and introduce an ion generating gas and microwave into the plasma chamber that is in the magnetic field. And
A confined magnetic field in a direction coinciding with the central axis direction of the plasma chamber generates a plasma having an elongated cross-sectional shape that intersects the central axis of the plasma chamber at a right angle, and an ion beam is provided on one end side of the plasma chamber. It is configured to be pulled out by electrodes,
The confinement magnetic field in the plasma chamber is such that the central axis of the mirror magnet coincides with the central axis of the multipolar permanent magnet device, and the directions of the pair of mirror magnetic fields generated by the mirror magnet coincide on the central axis. West,
For connection with the waveguide for introducing microwaves, the plasma chamber, the base frame, and at least one connection portion is provided on a side peripheral portion of the triple structure of the multipolar permanent magnet device. The connecting portion is positioned between the rod-like permanent magnets of the multipolar permanent magnet device, and is formed into a long hole shape parallel to the central axis direction of the plasma chamber and the base frame in the radial direction of the plasma chamber. So that microwaves can be introduced through the connection,
A supply port for indirect heating of the ion source gas substance by immersing a vacuum container loaded with the ion source gas substance in a solid state in a temperature-controlled liquid, and supplying the gas source by gasification is provided at one end on the central axis of the plasma chamber. A molecular ion enhanced ion source apparatus that performs plasma generation by ECR by being provided on the side.   2. The multipolar permanent magnet according to claim 1, wherein one end side or both end sides on the lead electrode side of the multipolar permanent magnet device are arranged between the outer peripheral side of the end frame and the inner peripheral side of the mirror magnet. A molecular ion enhanced ion source device characterized in that a magnet device is provided.   2. The molecular ion enhanced ion source device according to claim 1, wherein the end frame is provided integrally with the base frame.   2. The molecule according to claim 1, wherein the mirror magnet and the multipolar permanent magnet device on the side opposite to the extraction electrode of the pair of mirror magnetic fields each generate a confined magnetic field having a maximum magnetic flux density of 2 kilogauss or more. Ion enhanced ion source device.   3. The molecular ion enhanced structure according to claim 2, wherein the confined magnetic field in the plasma chamber is configured so that the maximum magnetic flux density in the plasma chamber is 2 kilogauss or more by the multi-pole permanent magnet device on the end side. Ion source device.   2. The molecular ion enhanced ion source device according to claim 1, wherein a microwave of 2.45 (GHz) is introduced.   2. The molecular ion enhanced ion source device according to claim 1, wherein the microwave power is 100 (W) at the maximum.   2. The molecular ion enhanced ion source device according to claim 1, wherein solid decaborane is used as the ion source gas substance.

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