JP2001023564A - Exb device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an analyser which operates under high pressure environment such as a sputtering process, etc., has sufficient performances, is produced at low cost by using the surface of a magnetic pole or a magnet faced to a magnetic field space as an electrode forming a field. SOLUTION: Heteropolar conductive magnets 2, 3 are arranged opposed to each other and electrodes 51, 52 of non-magnetic materials having +V and -V impressed thereon and insulator films 53 and 54 of non-magnetic materials and silicon carbide films 55, 56 are interposed between the magnets 2, 3 and the electrodes 51, 52, a part forming a space is an electromagnetic field part 100, and a space inside the circle is a range for passing ion beams. The silicon carbide films 55, 56 are electrically contacted with the electrodes 51, 52 so that the surfaces of the magnets 2, 3 faced to the electromagnetic field part 100 are functioned as the electrodes forming the electromagnetic field, and the magnetic field by the magnets 2, 3 becomes a uniform magnetic field strength so that the electric field correction between the electromagnetic field space or the both of the electric field generation and the electrolytic correction can be performed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a mass analyzer for measuring the mass of gaseous molecules, and more particularly to a mass analyzer which operates even in a high pressure atmosphere during a process such as sputtering.

[0002]

2. Description of the Related Art The principle of mass measurement of gaseous molecules is that, after ionizing a molecule to be measured, the ions are electromagnetically mass-separated and only ions having a specific mass / charge value reach a collector. Then, the current is measured.

As an electromagnetic mass separation method, a method using only a high-frequency electric field and a magnetic field, and a method using a magnetic field and an electrostatic field are known. B type and the like.

In order to operate a mass spectrometer in a high pressure atmosphere during a process such as sputtering, in addition to the requirements for a normal mass spectrometer, 1) the process of ions separated by mass is short ( 2) It is necessary that stray ions scattered by gas molecules and electrodes do not reach the collector.

The condition 1) is necessary for the ions to be mass-separated to reach the collector without colliding with the high-pressure, that is, high-density, atmosphere gas. Of the same degree is required. In an ordinary sputtering process, since the atmosphere of Ar is about 1 Pa, the ion process in the mass spectrometer is 10 m.
m.

As a mass spectrometer satisfying such conditions, there is a mass filter type mass spectrometer having an ultra-miniaturized overall size. However, in the case of the mass filter type mass spectrometer, the precision of the quadrupole is strictly about 1 micron, and the frequency of the applied high frequency is as high as about 10 MHz. I have. In addition, since the energy of ions passing through the quadrupole must be as low as about 10 eV, it is difficult to distinguish scattered stray ions from ions that have been normally mass-separated, and sufficient performance is achieved. Not.

[0007] A mass spectrometer, also called an E × B (Eixroby) type, also known as a Wien filter type, passes ions through a space (electromagnetic field portion) in which a magnetic field and an electric field are orthogonal to each other to obtain a specific mass / charge value. This is a method in which mass spectrometry is performed by moving only the held ions straight, and has the advantages that the structure is simple and the accuracy and electric control are not strict.

However, the E × B type mass spectrometer has a practical difficulty in generating a magnetic field, and is not widely used as a mass spectrometer. It is only slightly used for purifying irradiated ions by ion implantation equipment. In this case, since the masses of the irradiation ions and the contaminating impurities are greatly different, a mass resolution (width) of about 10 mass units (atom mass: amu) is sufficient. In addition, since it is usually used in a low-pressure atmosphere of 10 ⁻⁴ Pa or less, the ion stroke in the mass spectrometer is set to about 100 mm and the magnetic pole gap is set to about 30 mm in most cases.

In a mass analyzer using only a magnetic field, such as a sector type mass analyzer, the magnetic field generation space, that is, the magnetic pole gap can be considerably narrowed, so that the electromagnet or the magnet is not so large. However, in the E × B mass spectrometer, the magnetic field and the electrostatic field must be orthogonal to each other, so that the magnetic pole gap becomes large and the electromagnet and the magnet become large.

FIGS. 7A and 7B show a conventional example of an electromagnetic field portion of an E × B type mass spectrometer. In FIG. 7A, reference numeral 1
Denotes a yoke, reference numerals 2 and 3 denote magnets, and reference numerals 51 and 52 denote electrodes. FIG. 7B is an enlarged view of a portion indicated by a broken line 104 in FIG. 7A, which is indicated by reference numeral 100 surrounded by magnets 2 and 3 and electrodes 51 and 52. The space shown is the electromagnetic field portion, and the inside of the circle indicated by reference numeral 101 is the range through which the ion beam passes. Also,
In FIG. 7B, lines of electric force are generated as indicated by reference numeral 102, and lines of magnetic force are generated as indicated by reference numeral 103.
The distance between the magnets 2 and 3 in the electromagnetic field portion corresponds to the magnetic pole gap. Here, a permanent magnet is used to generate a magnetic field, and the magnet directly faces the electromagnetic field without using a magnetic pole. The ions to be mass-separated are traveling from the back side to the front side of the plane of the paper perpendicularly to the plane of the paper, and the diameter thereof is represented as a circle 101. As shown by the lines of electric force 102 and the lines of magnetic force 103, the magnetic field is formed in the vertical direction in the figure, and the electric field is formed in the horizontal direction.

The basic operation of the E × B type mass spectrometer is as follows: the range through which the ion beam passes, ie, FIG.
Inside, the intensity of the magnetic field and the electric field must be uniform and orthogonal at the inside of the circle indicated by reference numeral 101.
If this condition is satisfied, of the ion beam that has traveled from the back side of the paper to the front side perpendicular to the paper,
Only ion beams with a specific mass / charge amount go straight,
Other ion beams are deflected to the left and right. Changing the strength of the magnetic field and the electric field changes the mass / charge amount of the ion beam traveling straight. Therefore, if an aperture and a collector electrode are provided at a position where the ion beam goes straight, mass separation can be performed. If the intensity of the electric and magnetic fields is not uniform, the sensitivity and resolution will be degraded.

In FIGS. 7A and 7B, the width of the electrode is increased in order to ensure the uniformity of the electric field. Due to the presence of this large width electrode, the pole gap is necessarily large. In order to ensure the uniformity of the magnetic field even in this large pole gap, the width of the magnets 2 and 3 is large. For these reasons, the magnets 2 and 3 and the yoke 1 must be very large.

For these reasons, the E × B type mass analyzer has hardly been used as a normal mass analyzer. Furthermore, as a mass spectrometer capable of operating even in a high pressure atmosphere during a process such as sputtering, an ExB mass spectrometer has never been used.

As for the conventional E × B type mass spectrometer, JP-A-4-351840 and JP-A-7-16133 which use a plurality of electromagnets to improve the uniformity of the magnetic field.
No. 7-13200, in which a voltage is applied to a magnetic pole to deflect an ion beam in a direction perpendicular to the direction of mass separation.
No. 7 exists.

[0015]

The object of the present invention is to
An object of the present invention is to realize a mass spectrometer which can be operated in a high pressure atmosphere during a process such as sputtering, has sufficient performance, and has a low production cost.

In order to operate in a high-pressure atmosphere, it is required that the ion stroke in the mass spectrometer is very short as described above. To achieve this, it is necessary to make the pole gap of the E × B mass spectrometer very small. This is for the following two reasons.

The first reason is an end face (fringing) effect, which is a problem common to all mass spectrometers. That is, in the vicinity of the end face of the electromagnetic field space, the electromagnetic field strength becomes weak due to the influence of the outer space where no electromagnetic field exists, and mass separation cannot be performed in that part. That is, the length in the ion passage direction that can be effectively separated by mass is reduced. Specifically, it is known that effective mass separation is not performed for the lengths of about half the electrode gap and the magnetic pole gap inside the respective end faces of the inlet and the outlet. For a sputtering process of about 1 Pa, the length of the mass separation portion must be about 10 mm. Therefore, if an attempt is made to secure a length for effective mass separation of about 7 mm, the electrode gap and the magnetic pole gap are reduced by about 3 mm.
mm.

The second reason is to achieve the required strong magnetic field strength. About 10mm (effectively about 7m
In order to perform mass separation with sufficient resolution in a mass separation section having a short m), a strong magnetic field strength is required.
Water (18 am) which is a particular problem in the sputtering process
In order to measure u) separately from Ar ²⁺ (40 amu) serving as a background, a magnetic field strength of 5 to 10 kGauss is required. In order to achieve such a strong magnetic field strength without using an extremely large electromagnet or magnet, the magnetic pole gap needs to be very small, about 3 to 5 mm.

However, if the magnetic pole gap is shortened to about 3 mm with the conventional structure of the E × B type mass spectrometer, a large problem arises in performance. This state is shown in FIG. In FIG. 8, the uniformity of the magnetic field is maintained, but the uniformity of the electric field is not ensured. That is, the width of the electrodes 51 and 52 is reduced due to the reduced magnetic pole gap, and the circle indicated by the reference numeral 101 is a range through which the ion beam traveling from the back side to the front side of the paper perpendicularly to the paper passes. , The surfaces of the magnets 2 and 3 are present in the immediate vicinity. The surfaces of the magnets 2 and 3 have a certain voltage when the magnet is a conductor, and have a random potential with respect to time and place when the magnet is an insulator. Instead of a uniform electric field in which the potential surface is parallel to the electrode surface, a distorted electric field distribution is strongly influenced by the potential of the magnet.

[0020]

SUMMARY OF THE INVENTION The present inventor has focused on an ExB mass analyzer as a mass analyzer that can operate at high pressure. In other words, the ExB mass spectrometer has a simple structure and an ion energy of 100 to 1000 eV.
It was thought that it was essentially suitable for a high pressure mass spectrometer because it could be higher. In particular, high ion energy means that stray ions that form the background and ions that have been normally mass-separated can be easily separated with a simple electrostatic deflector separately. It will be a great advantage. In view of this, an invention relating to an electromagnetic field forming technique was performed, and the above problem was attempted to be solved by causing a magnetic pole or a surface of a magnet for forming a magnetic field in an E × B type mass analyzer to function as an electrode for forming an electric field. Things.

[0021]

DESCRIPTION OF THE PREFERRED EMBODIMENTS To solve the above-mentioned problems, an E × B apparatus proposed by the present inventors is as follows.

That is, it is composed of an electrode for forming an electric field and a magnetic pole or a magnet for forming a magnetic field.
An E × B apparatus for performing energy separation, wherein a magnetic pole or a surface of a magnet facing an electromagnetic field space is caused to function as an electrode for forming an electric field. By making the magnetic poles or magnet surfaces facing the electromagnetic field space function as electrodes for forming an electric field as described above, it is possible to perform electric field correction in the electromagnetic field space, or both electric field generation and electric field correction. Even if the magnetic pole gap is reduced by bringing the opposing magnetic poles or magnets closer to each other for forming a magnetic field, a uniform electric field in which the equipotential surface between the electrodes is parallel to the electrode surface can be formed.

In the above, in order to make the surface of the magnetic pole or magnet facing the electromagnetic field space function as an electrode for forming an electric field, a configuration is adopted in which a quasi-conductive film is provided on the surface of the magnetic pole or magnet facing the electromagnetic field space. can do.
By providing a quasi-conductive film, for example, a thin film of silicon carbide, having a uniform sheet resistance value on the surface facing the magnetic field or the electromagnetic field space of the magnetic pole or magnet, the electric potential of the surface along the direction of the electric field is increased. It can change at a constant increase or decrease rate, and performs electric field correction in the electromagnetic field space, or both generation and correction of the electric field in the electromagnetic field space.

In the above-described E × B apparatus, the quasi-conductor film is not provided on the surface of the magnetic pole or the magnet facing the electromagnetic field space.
A plurality of magnetic poles or magnets each electrically insulated are arranged in the same magnetic pole direction, and a plurality of magnetic poles or magnets respectively electrically insulated such that different magnetic poles face the plurality of magnetic poles or magnets. The magnetic poles are arranged side by side in the same magnetic pole direction, and the surfaces of a plurality of magnetic poles or magnets facing each other may be configured to function as electrodes for forming an electric field. Even with such a configuration, the potential applied to the magnetic pole or the magnet for forming a magnetic field facing the different magnetic poles is a predetermined value with respect to the potential applied to the electric field forming electrode, for example, , 電位, or the same potential, it is possible to perform the electric field correction in the electromagnetic field space, or both the electric field generation and the electric field correction in the electromagnetic field space. As described above, a plurality of magnetic poles or magnets which are electrically insulated are arranged in the same magnetic pole direction, and a plurality of magnetic poles or magnets which are respectively electrically insulated such that different magnetic poles face the plurality of magnetic poles or magnets. Even if the magnetic poles or magnets are arranged in the same magnetic pole direction to form a magnetic pole or magnet for forming a magnetic field, the surfaces of these magnets are not too close to the range where the ion beam passes,
An electric field and a magnetic field in an electromagnetic field space can be obtained by cutting off the approaching corners of a plurality of magnetic poles or magnets that are electrically insulated and arranged in the same magnetic pole direction. Can be improved.

Further, another invention proposed by the present application is to dispose a plurality of electrically insulated conductive magnetic poles or magnets in a point-symmetrical manner, and a central portion where the plurality of conductive magnetic poles or magnets face each other. An E × B apparatus for forming an electromagnetic field in which an electric field and a magnetic field are orthogonal to each other to separate mass and energy of charged particles, wherein the plurality of conductive magnetic poles or magnets also function as electrodes for forming an electric field The potential of the surface facing the electromagnetic field space is, in addition to the voltage for mass separation, the relationship of the linear combination of the deflection voltage and the astigmatism correction voltage, or the deflection voltage, the astigmatism correction voltage and the convergence voltage. An E × B apparatus characterized by being adjusted to have a linear coupling relationship. By adjusting the electric potential of the surface of the plurality of conductive magnetic poles or magnets facing the electromagnetic field space that also functions as electrodes for forming an electric field to the above-described specific relationship, electric field correction in the electromagnetic field space, or electromagnetic In addition to performing both electric field generation and electric field correction in the field space, deflection and astigmatism correction of charged particles, or deflection of charged particles,
Astigmatism correction and convergence can be performed.

Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings. However, the present invention is not limited to the embodiment described in the following embodiment, and the technical embodiments described in the present specification are not limited thereto. Various changes can be made within the scope of creation of thought.

[0027]

Embodiment 1 FIG. 1 is a diagram showing a schematic configuration of a first embodiment of the present invention.

Conductor magnets 2 and 3 are arranged so that the opposite poles face each other.
Non-magnetic electrode 5 to which V and -V voltages are applied
1, 52 are arranged.

Between the magnets 2 and 3 and the electrodes 51 and 52,
The non-magnetic insulating films 53 and 54 and the non-magnetic silicon carbide films 55 and 56 are used as the silicon carbide films 55 and 56 for the electrode 5.
1, 52 are provided so as to be in electrical contact with each other.

In FIG. 1, a space surrounded by magnets 2 and 3 and electrodes 51 and 52 and denoted by reference numeral 100 is an electromagnetic field portion.
The inside of the circle denoted by reference numeral 101 is a range where the ion beam traveling from the back side to the front side of the paper perpendicular to the paper surface passes.

In this embodiment as well, FIG.
(B) Electric force lines in the direction indicated by reference numeral 102, reference numeral 10
Magnetic lines of force in the direction indicated by 3 are generated, but these are omitted in FIG. Further, a yoke indicated by reference numeral 1 in FIG. 7A of the conventional example exists, but is omitted in FIG.

The distance between the magnets 2 and 3 in the electromagnetic field portion 100 corresponds to the magnetic pole gap, which is set to about 3 mm in this embodiment.

In the present invention, the magnets 2 and 3 and the electrode 5
Silicon carbide films 55, 5 interposed between
6 is in electrical contact with the electrodes 51 and 52, so that the surfaces of the magnets 2 and 3 facing the electromagnetic field space 100 function as electrodes for forming an electromagnetic field.

Further, the silicon carbide films 55 and 56 are made of 10 ⁵
It is composed of a film having a uniform sheet resistance value of about 910 ⁹ Ω, so that the electrodes 51 and 52 are in contact with the surfaces of the magnets 2 and 3 via the insulating films 53 and 54. The potential of the silicon carbide films 55 and 56, that is, the electrodes 51 and 5
Between the two, the potentials of the surfaces of the magnets 2 and 3 facing the electromagnetic field space are the electrodes 51 and 52 to which + V and -V voltages are applied.
Is determined by the distance from the electrode surface, and changes at a constant rate of increase or decrease along the direction of the electric field (the direction of the lines of electric force not shown). As a result, the potential in the electromagnetic field portion 100 is equal to the potential of the electrodes 51 and 52 +
V, -V equal electric field strength, that is, the electrode 5
A uniform electric field is formed such that the equipotential surface between the electrodes 1 and 52 is parallel to the surfaces of the electrodes 51 and 52.

On the other hand, electrodes 51 and 52, insulating films 53 and 5
4 and the silicon carbide films 55 and 56 are all made of a non-magnetic material, so that the magnetic field generated by the magnets 2 and 3 is not disturbed by these and has a uniform magnetic field intensity.

As described above, in this embodiment, despite the magnetic pole gap being reduced to about 3 mm, the ideal electromagnetic field in which the intensity of the magnetic field and the electrolysis is uniform and orthogonal to each other in the electromagnetic field portion 100. A part is formed.

In this embodiment, the insulating film 5
Although the magnets 3 and 54 were used, the magnets 2 and 3 used in this embodiment were made of such a structure because they were conductors. When magnets 2 and 3 are insulators, insulating films 53 and 54 are interposed between silicon carbide films 55 and 56 that are in electrical contact with electrodes 51 and 52 and the surfaces of magnets 2 and 3. do not have to.

A yoke 1 not shown in FIG.
Is effective in improving the strength of the magnetic field and decreasing the strength of the leakage magnetic field to the outside, but is not necessarily essential.

[0039]

Embodiment 2 FIG. 2 is a diagram showing a schematic configuration of a second embodiment of the present invention.

Conductor magnets 2 and 3 are arranged so that the opposite poles face each other, and a silicon carbide film made of a non-magnetic material is provided on their surfaces via insulating films 53 and 54 made of a non-magnetic material, respectively. 55 and 56 are provided.

Terminals 57 and 58 are electrically connected to the right end and the left end of the silicon carbide film 55 in FIG. 2, and similarly, the terminal 59 is connected to the right end and the left end of the silicon carbide film 56 in FIG. , 60 are electrically connected.

In FIG. 2, the space between the silicon carbide films 55 and 56 provided on the surfaces of the magnets 2 and 3 respectively becomes the electromagnetic field part 100. The inside of the circle denoted by reference numeral 101 is a range where the ion beam traveling from the back side to the front side of the paper perpendicular to the paper surface passes.

In this embodiment as well, FIG.
(B) Electric force lines in the direction indicated by reference numeral 102, reference numeral 10
Magnetic lines of force in the directions indicated by 3 will be generated, but these are omitted in FIG. Further, a yoke indicated by reference numeral 1 in FIG. 7A of the conventional example exists, but is omitted in FIG.

The distance between the magnets 2 and 3 in the electromagnetic field portion 100 corresponds to the magnetic pole gap.
mm.

As shown in FIG. 2, the terminals 57 and 59 have +
A voltage of -V is applied to V and the terminals 58 and 60, respectively. Thus, the surfaces of the silicon carbide films 55 and 56, that is, the magnets 2 and 3 facing the electromagnetic field space function as electrodes for forming an electromagnetic field.

Further, the silicon carbide films 55 and 56 are made of films having a uniform sheet resistance value of about 10 ⁵ to 10 ⁹ Ω as in the first embodiment shown in FIG. The potentials of the silicon films 55 and 56, that is, the potentials of the surfaces of the magnets 2 and 3 facing the electromagnetic field space are terminals 57 and 59 to which a voltage of + V is applied and terminals 58 and 59 to which a voltage of -V is applied. It becomes a value internally divided by the distance from 60, and changes at a constant increasing rate or decreasing rate along the electric field direction (the direction of the electric lines of force not shown). Therefore, the electric field in the electromagnetic field portion 100 has a uniform electric field intensity obtained by equally dividing + V and −V by the width of the magnets 2 and 3.

Further, similarly to the first embodiment, the insulating film 5
3, 54 and the silicon carbide films 55 and 56 are all made of a non-magnetic material, so that the magnetic field generated by the magnets 2 and 3 is not disturbed by the insulating films 53 and 54 and the silicon carbide films 55 and 56. The magnetic field strength is uniform.

As described above, even in the present embodiment, despite the magnetic pole gap being reduced to about 4 mm, in the electromagnetic field portion 100, the ideal electromagnetic field in which the intensity of the magnetic field and the electrolysis are uniform and orthogonal to each other. A part is formed.

The reason for using the insulating films 53 and 54 in the second embodiment is the same as that in the first embodiment. When the magnets 2 and 3 are insulators, the insulating films 53 and 54 are
It is not necessary to interpose between the silicon carbide films 55 and 56 and the surfaces of the magnets 2 and 3.

The yoke 1 not shown in FIG.
Is effective in improving the strength of the magnetic field and reducing the strength of the leaked magnetic field to the outside, but is not necessarily indispensable as in the first embodiment.

As compared with the first embodiment shown in FIG. 1, the configuration of the second embodiment has an advantage that the deflected ion beam does not scatter on the electrode because no electrode is required.

[0052]

Third Embodiment FIG. 3 is a diagram showing a schematic configuration of a third embodiment of the present invention.

The conductor magnets 4, 5, 6, and 7 are electrically insulated from the magnet 4 and the magnet 5, are arranged side by side so that the same poles are adjacent to each other, and the magnets 6 and 7 are also electrically connected. The magnets 4 and 5 are insulated and are arranged side by side so that the same poles are adjacent to each other, and the pair of magnets 6 and 7 arranged side by side are opposite to each other. Are located.

Non-magnetic electrodes 51 and 52 to which voltages of + V and -V are applied are arranged between the magnets 4 and 5 and the magnets 6 and 7 thus arranged. .

Further, as shown in FIG.
Have a voltage of + V / 2, and the magnets 5 and 7 have −
A voltage of V / 2 is applied. Thus, magnet 4,
A voltage is applied to 5, 6, and 7, between the magnet 4 and the magnet 5,
Further, the magnet 4 and the magnet 5 and the magnet 6 and the magnet 7 are juxtaposed and electrically insulated so that an electric field is formed between the magnet 6 and the magnet 7, respectively. In this embodiment, electrical insulation is attained by providing gaps between the magnets 4 and 5 and between the magnets 6 and 7, respectively. It suffices that the discharge does not occur between the electrodes and the electric field is large enough to maintain the electric field. In addition, without providing a gap, an insulating film can be interposed between the magnets 4 and 5 and between the magnets 6 and 7 to achieve electrical insulation.

In FIG. 3, magnets 4, 5, 6, 7 and electrodes 5
A space surrounded by reference numerals 1 and 52 and denoted by reference numeral 100 is an electromagnetic field portion. The inside of the circle denoted by reference numeral 101 is a range where the ion beam traveling from the back side to the front side of the paper perpendicular to the paper surface passes.

In this embodiment, the conventional example shown in FIG.
(B) Electric force lines in the direction indicated by reference numeral 102, reference numeral 10
Magnetic lines of force in the direction indicated by 3 are generated, but these are omitted in FIG. Further, a yoke indicated by reference numeral 1 in FIG. 7A of the conventional example exists, but is omitted in FIG.

The distance between the magnets 4 and 5 and the magnets 6 and 7 in the electromagnetic field portion 100 corresponds to the magnetic pole gap, and is about 5 mm in this embodiment.

The magnets 4, 5,
The potentials on the surfaces of 6, 7 are the same as those of the first and second embodiments shown in FIGS.
Although the potentials are not equally divided as in the case of the above, the electrodes to which the voltages of + V and -V are applied since the voltages of + V / 2 and -V / 2 are applied as described above. 5
The potential is an intermediate value between 1 and 52.

The range 101 through which the ion beam passes
The magnets 4, 5, 6, and 6 in the direction of the electromagnetic field unit 100 are separated from each other so as to help improve the uniformity of the electric and magnetic fields.
As shown in FIG. 3, corners 7 are cut.

As a result, a substantially uniform electric field is formed in the electromagnetic field portion 100.

On the other hand, when examining the magnetic field in the electromagnetic field section 100, the magnets 4 and 5 are electrically different in electric potential, but are magnetically arranged side by side with only a small gap at the center. Since the angle toward the electromagnetic field part 100 is only cut, the magnets 4 and 5 arranged in parallel operate in substantially the same manner as the magnet 2 in the first embodiment shown in FIG. The same applies to the magnets 6 and 7 arranged opposite to each other, and the magnets 6 and 7 arranged in parallel perform almost the same operation as the magnet 3 in the embodiment 1 shown in FIG.

Since the electrodes 51 and 52 are made of a non-magnetic material, the magnetic field generated by the magnets 4, 5, 6 and 7 is not disturbed by the electrodes 51 and 52 and has a uniform magnetic field intensity. Become.

Therefore, also in this embodiment, a substantially uniform magnetic field is formed in the electromagnetic field portion 100.

Therefore, also in this embodiment, the magnetic pole gap is set to 5
mm.
In this case, an ideal electromagnetic field portion in which the strengths of the magnetic field and the electric field are uniform and orthogonal to each other is formed.

When the embodiment shown in FIG. 3 is compared with the first and second embodiments (FIGS. 1 and 2), the surface of the magnet itself facing the electromagnetic field space functions as an electrode for forming an electric field. Another advantage is that it is not necessary to use a silicon carbide film.

[0067]

Embodiment 4 FIG. 4 is a diagram showing a schematic configuration of a fourth embodiment of the present invention.

The conductor magnets 8, 9, 10, 11 are such that the magnet 8 and the magnet 9 are electrically insulated from each other,
The magnets 10 and 1 are arranged side by side so that the same poles are adjacent to each other.
1 are also electrically insulated from each other, are arranged side by side so that the same poles are adjacent to each other, and have a set of magnets 8 and 9 arranged side by side and a set of magnets 10 and 11 arranged side by side. However, they are arranged so as to face each other.

The non-magnetic electrodes 61 and 62 to which the voltages + V and -V are applied are interposed between the magnets 8 and 9 and the magnets 10 and 11 arranged as described above. Electrode 61, magnets 8, 10 and electrode 6
2 and the magnets 9 and 11 are electrically connected to each other.

The magnets 8, 9 facing the electromagnetic field part 100,
Unlike the case of the third embodiment shown in FIG. 3, the surface potentials of the electrodes 10 and 11 are not intermediate potentials of the electrodes 61 and 62. , And thus have the same potential as the electrodes 61 and 62.

As described above, the magnets 8 and 9 and the magnets 10 and 11 are formed so that an electric field is formed between the magnets 8 and 10 and the magnets 9 and 11 having the same potential as the electrodes 61 and 62, respectively. And are juxtaposed electrically insulated from each other. In this embodiment, electrical insulation is achieved by providing gaps between the magnets 8 and 9 and between the magnets 10 and 11, respectively.
It is sufficient that no discharge occurs between these magnets and the magnitude is such that an electric field can be maintained. Further, without providing a gap, an insulating film can be interposed between the magnets 8 and 9 and between the magnets 10 and 11 to achieve electrical insulation.

In FIG. 4, a space surrounded by magnets 8, 9, 10, 11 and electrodes 61, 62 and denoted by reference numeral 100 is an electromagnetic field portion. The inside of the circle denoted by reference numeral 101 is a range where the ion beam traveling from the back side to the front side of the paper perpendicular to the paper surface passes.

In this embodiment, the conventional example shown in FIG.
(B) Electric force lines in the direction indicated by reference numeral 102, reference numeral 10
Magnetic lines of force in the direction indicated by 3 are generated, but these are omitted in FIG. Further, a yoke indicated by reference numeral 1 in FIG. 7A of the conventional example exists, but is omitted in FIG.

The distance between the magnets 8 and 9 and the magnets 10 and 11 in the electromagnetic field portion 100 corresponds to the magnetic pole gap, and is about 5 mm in this embodiment.

Further, as in the third embodiment, by further increasing the distance between the ion beam and the range 101, the ion beam is directed toward the electromagnetic field portion 100 so as to improve the uniformity of the electric field and the magnetic field. The corners of the magnets 8, 9, 10, 11 are
As shown in FIG. 4, each is cut further deeper.

Thus, also in this embodiment, a substantially uniform electric field is formed in the electromagnetic field portion 100.

On the other hand, when examining the magnetic field in the electromagnetic field unit 100, a substantially uniform magnetic field is formed in the electromagnetic field unit 100 in this embodiment also for the same reason as in the third embodiment (FIG. 3). I have.

Therefore, also in this embodiment, the magnetic pole gap is set to 5
In spite of the reduction to mm, an ideal electromagnetic field portion in which the strength of the magnetic field and that of the electrolysis are uniform and orthogonal to each other is formed in the electromagnetic field portion 100.

Compared to the third embodiment, the fourth embodiment is advantageous in that the parts are simplified.

[0080]

Fifth Embodiment FIG. 5 is a diagram showing a schematic configuration of a fifth embodiment of the present invention.

At the center of the yoke 1, conductive magnets 12, 13, 14, 1 are connected via an insulating magnet mounting ring 16.
5 are mounted electrically insulated.

The space surrounded by the magnets 12, 13, 14, 15 constitutes the electromagnetic field section 100,
Is the range through which the ion beam traveling from the back side to the front side of the paper perpendicular to the paper surface passes. In FIG. 5, the lines of electric force are generated as indicated by reference numeral 102, and the lines of magnetic force are generated as indicated by reference numeral 103.

In this embodiment, as shown in FIG. 5, the magnets 12 and 13 are arranged so that the same poles are adjacent to each other in a perpendicular direction. Similarly, the magnets 14 and 15 are also arranged so that the same poles are adjacent to each other in a perpendicular direction. And magnet 12 and magnet 14, magnet 13 and magnet 15
And are arranged so that the opposite poles face each other.

The four magnets have the same shape and are arranged four times rotationally symmetric with respect to the center. Such a magnet 1
The arrangement of 2, 13, 14 and 15 is similar to a quadrupole lens known as a strong focus lens, but the orientation of the magnetic poles is different.

By the arrangement of the magnets as described above, reference numeral 1
The lines of magnetic force represented by 03 are magnets 12, 13, 14, 15
In the range 101 through which the ion beam passes in the space surrounded by the circles, the direction from the bottom to the top in FIG. 5 is reached, and a substantially uniform magnetic field is formed in this space.

The voltages V1, V2, V3, and V4 shown below are applied to the magnets 12, 13, 14, and 15, respectively, so that not only the mass separation as ExB but also the electrostatic deflector The X-axis and Y-axis deflection of the ion beam and the primary astigmatism correction of the ion beam as an electrostatic astigmatism corrector can be performed.

Magnet 12: V1 = + Vm + Vy−Vs Magnet 13: V2 = −Vm−Vx + Vs Magnet 14: V3 = −Vm−Vy−Vs Magnet 15: V4 = + Vm + Vx + Vs where Vm: voltage for mass separation, Vx: X Axial deflection voltage, Vy: Y-axis deflection voltage, Vs: Astigmatism correction voltage.

Focusing on the mass separation voltages + Vm and -Vm, in FIG. 5, the right magnets 12 and 15 have a potential of + Vm, and the left magnets 13 and 14 have a potential of -Vm.

Since the magnets 12 and 15 and the magnets 13 and 14 are line-symmetric with respect to the horizontal direction in FIG. 5, the lines of electric force are in the horizontal direction near the center. Therefore, a substantially uniform electric field in the horizontal direction is formed near the center by + Vm and -Vm.

Therefore, as described above, a substantially uniform magnetic field from the bottom to the top in FIG. 5 near the center of the magnets 12 to 15 and a substantially uniform electric field in the horizontal direction near the center in FIG. , Mass separation is performed as ExB.

As described above, in order to apply different voltages to the four magnets 12 to 15 to form electric fields, the magnets 12, 13, 14, 15 are electrically connected as described above. Must be insulated.

In this embodiment, the magnets 12 to 15
Are electrically insulated from each other by arranging a gap between each of them. The interval of this gap is determined by the magnet 12
It is sufficient that a discharge is not generated between each of Nos. 1 to 15 and that the electric field can be maintained. It is to be noted that an electrical insulation can be achieved by interposing an insulating film between each of the magnets 12 to 15 without using a configuration in which a gap is arranged.

XV direction deflection voltages + Vx, -Vx
Note that the lower right magnet 15 is + Vx and the upper left magnet 1
3 is the potential of -Vx. Therefore, + Vx,
The ion beam is deflected in the X-axis direction by −Vx.
Similarly, the ion beam is deflected in the Y-axis direction by + Vy and -Vy.

When attention is paid to the astigmatism correction voltages + Vs and -Vs, the potentials of the magnets facing each other become equal potentials, and the potentials of the magnets in the perpendicular direction are opposite in polarity. Therefore, primary astigmatism correction for adjusting the shape of the ion beam in the one-dimensional direction by + Vs and -Vs is performed.

Compared to the embodiment (FIG. 4), the embodiment 5 has an advantage that the parts are simpler.

[0096]

Sixth Embodiment FIG. 6 is a diagram showing a schematic configuration of a sixth embodiment of the present invention.

In the center of the yoke 1, conductive magnets 17, 18, 19, 2
Reference numerals 0, 21, 22, 23, and 24 are attached so as to be electrically insulated from each other.

The space surrounded by the magnets 17 to 24 constitutes the electromagnetic field part 100, and the inside of the circle denoted by reference numeral 101 advances from the back side of the paper to the front side perpendicular to the paper. Is the range through which the ion beam comes.

As shown in FIG. 6, the magnets 17, 18, 1
9 and 20 are arranged so that the same poles are adjacent to each other at an angle of 45 degrees, and the magnets 21, 22, 23 and 24 are also arranged at 45 degrees.
The same poles are arranged next to each other with an angle of degrees. Then, the magnet 17 and the magnet 21 and the magnet 18 and the magnet 2
2. The magnet 19 and the magnet 23, and the magnet 20 and the magnet 24 are arranged such that different poles face each other. The eight magnets have the same shape and are arranged eight times rotationally symmetric with respect to the center.

With the arrangement of the magnets as described above, the magnet 1
In the range 101 through which the ion beam passes in the space surrounded by 7 to 24, a substantially uniform magnetic field is formed from below to above in FIG.

The magnets 17 to 24 have V1, V2, V3, V4, V5, V6, V7, and V8 shown below, respectively.
Is applied, and not only the mass separation as an E × B apparatus, but also the X and Y of an ion beam as an electrostatic deflector.
Axial deflection, secondary astigmatism correction of the ion beam as a stigmator, and convergence of the ion beam in the X-axis direction as a three-dimensional focusing mass analyzer can be performed.

Magnet 17: V1 = + Vm + Vdx + a.Vdy + Vsx + Vf Magnet 18: V2 = + Vm + a.Vdx + Vdy + Vsy Magnet 19: V3 = -Vm-a.Vdx + Vdy-Vsx-Vf Magnet 20: V4 = -Vm-Vd-Vm -Vsy-Vf Magnet 21: V5 = -Vm-Vdx-a.Vdy + Vsx-Vf Magnet 22: V6 = -Vm-a.Vdx-Vdy + Vsy-Vf Magnet 23: V7 = + Vm + a.Vdx-Vdy-Vsx magnet 24: V8 = + Vm + Vdx-a.Vdy-Vsy + Vf where Vm: voltage for mass separation, Vdx: voltage for deflection in the X axis direction, Vdy: voltage for deflection in the Y axis direction, Vsx: for astigmatism correction in the X axis direction Voltage, Vsy: Y-axis direction astigmatism correction voltage,
Vf: X-axis direction convergence voltage, a: an arbitrary coefficient.

Looking at + Vm and -Vm, in FIG. 6, the right magnets 17, 18, 23, and 24 have a potential of + Vm, and the left magnets 19, 20, 21, and 22 have a potential of -Vm.
Magnets 17 and 18 and magnets 23 and 24 and magnets 19 and 2
Since 0 and the magnets 21 and 22 are line-symmetric with respect to the horizontal direction in FIG. 6, the electric force lines are in the horizontal direction near the center. Therefore, a substantially uniform electric field in the horizontal direction is formed near the center portion by + Vm and -Vm.

Therefore, as described above, a substantially uniform magnetic field from the bottom to the top in FIG. 6 near the center of the magnets 17 to 24 and a substantially uniform electric field in the horizontal direction near the center in FIG. , Mass separation is performed as ExB.

As described above, in order to apply different voltages to the eight magnets 17 to 24 to form electric fields, the magnets 17 to 24 are electrically insulated as described above. There is a need.

In this embodiment, the magnets 17 to 24
Are electrically insulated from each other by arranging a gap between each of them. The spacing of this gap is determined by the magnet 17
It suffices that the discharge is not generated between each of the first to fourth embodiments and that the electric field can be maintained. It is to be noted that an electrical insulation can be achieved by interposing an insulating film between each of the magnets 17 to 24 without using a configuration in which a gap is arranged.

+ Vdx, -Vdx, + Vdy, -Vdy
Although the detailed description is omitted, the principle of operation is well known as an octupole electrostatic astigmatism corrector for large deflection angles. In conclusion, +
Vdx, -Vdx causes deflection in the X-axis direction to be + Vdy,-
The deflection in the Y-axis direction is performed by Vdy.

+ Vsx, -Vsx, + Vsy, -Vsy
Although the detailed description is omitted here, this operation principle
It is well known as a polar electrostatic stigmator. As a result, secondary astigmatism correction for adjusting the shape of the ion beam in the two-dimensional direction is performed based on + Vsx, -Vsx, + Vsy, and -Vsy.

It is known that an E × B type mass analyzer having a uniform electromagnetic field space has a function of converging an ion beam in the direction of a magnetic field, but has no function of converging in a direction of an electric field. Therefore, a method is known in which a curved electrode is used to slightly curve the electric field in the electrode field space so as to have a convergence effect also in the direction of the electric field. According to the conventional example shown in FIG. 7, the electrodes 51 and 52 are not flat plates but curved in an arc shape. By this method, so-called three-dimensional convergence in which the ion beam converges in two-dimensional directions is achieved.

In this embodiment, the conductive magnets 17 to 24, which also function as electrodes, have the same shape.
This function can be realized. That is, by applying + Vf to the two rightmost magnets and applying -Vf to the four leftmost magnets, the electric field in the electromagnetic field space is slightly curved rightward. Thus, in the present embodiment, three-dimensional convergence of the ion beam is achieved.

The present invention described above with reference to the accompanying drawings is substantially completely different from the technical concept disclosed in the above-mentioned patent application relating to the conventional E × B mass spectrometer. .

That is, in JP-A-4-351840 and JP-A-7-161337, a plurality of magnetic poles are used, but the additional magnetic pole is provided on the back side of the electrode. It does not itself generate or correct the electric field.

In JP-A-6-132007, a voltage is applied to the magnetic pole itself. However, the electric field caused by this voltage only functions to deflect the ion beam. The applied voltage does not generate an electric field for mass separation orthogonal to the magnetic field.

In the above description, a magnet that does not use magnetic poles is used for generating a magnetic field. However, the present invention is not limited to such an embodiment. A magnet using magnetic poles can be used, and an electromagnet can be used instead of a magnet.

When a magnetic pole is used, the formation of a silicon carbide film as a quasi-conducting film provided on the magnet surface facing the electromagnetic field space in the first and second embodiments shown in FIGS. 3,
The shapes and arrangements of the magnets in the vicinity of the electromagnetic field space performed in the embodiments 3, 4, 5, and 6 shown in FIGS. 4, 5, and 6 may be realized for the magnetic poles.

In Examples 1 and 2, the silicon carbide films 55 and 56 having uniform sheet resistance were formed on the surfaces of the magnets 2 and 3, but the present invention is not limited to such an embodiment. For example, a plurality of elongated conductive films may be formed side by side along the direction of the electric field in an insulated state, and a divided potential may be applied to each conductive film using another silicon carbide film or a resistor. Alternatively, a quasi-conductive film having a small sheet resistance value may be formed so as to be folded in a single stroke along the direction of the electric field. In addition, whatever the configuration, the thin film formed on the surface of the magnet facing the electromagnetic field space may cause the potential on the surface of the magnet to change monotonically along the direction of the electric field.

In Examples 3 and 4, two magnets are arranged in the same magnetic pole direction, but the present invention is not limited to such an embodiment. Three or more magnets can be arranged in the same magnetic pole direction. In addition, any configuration may be used as long as a plurality of electrically insulated magnets can be arranged in the same magnetic pole direction to generate an electric field in the electrode boundary space and correct the electric field.

The size and angle of the angle cut of the magnet for improving the uniformity of the electric and magnetic fields employed in the third and fourth embodiments shown in FIGS. 3 and 4 can be changed. It can also be a curved cut. Preferably, the optimum shape is determined by computer simulation.

In Examples 5 and 6, four or eight magnets of the same shape were used symmetrically, but the present invention is not limited to such an embodiment. Different shaped magnets can be used, or six or ten magnets can be used. In any other configuration, the potentials of a plurality of electrically insulated magnetic poles or magnets are changed with a certain relationship, so that not only electric field generation in the electromagnetic field space, electric field correction, but also ion beam It is only required that deflection, astigmatism correction, and convergence can be performed.

In the above description, the EXB apparatus of the present invention has been described as a mass spectrometer which operates even in a high-pressure atmosphere. However, the EXB apparatus of the present invention is used only in such a high-pressure atmosphere. Not something. It can also be used as a mass spectrometer operating in a normal pressure atmosphere or for purifying an ion beam.

Further, the application of the ExB apparatus of the present invention is not limited to the mass spectrometer. That is, in the above-described embodiment, only the case where the ExB apparatus of the present invention is used for the purpose of mass separation of ions having the same energy has been described, but the present invention is not limited to this. It can also be used for energy separation of ions and electrons with the same mass.

[0122]

According to the present invention, it is possible to provide a mass spectrometer which can be operated in a high pressure atmosphere during a process such as sputtering, has sufficient performance, and has a low production cost. I can do it.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram of a first preferred embodiment of an E × B apparatus of the present invention.

FIG. 2 is a schematic configuration diagram of a second preferred embodiment of the E × B apparatus of the present invention.

FIG. 3 is a schematic configuration diagram of a third preferred embodiment of the E × B apparatus of the present invention.

FIG. 4 is a schematic structural diagram of a fourth preferred embodiment of the E × B apparatus of the present invention.

FIG. 5 is a schematic configuration diagram of a fifth preferred embodiment of the E × B apparatus of the present invention.

FIG. 6 is a schematic configuration diagram of a sixth preferred embodiment of the E × B apparatus of the present invention.

FIG. 7A is a schematic configuration diagram of a conventional E × B apparatus,
FIG. 8B is an enlarged view of a part of the E × B apparatus shown in FIG.

FIG. 8 is a schematic configuration diagram illustrating a case where a magnetic pole gap is reduced in a conventional E × B apparatus.

[Explanation of symbols]

1 yoke 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12,
13, 14, 15, 17, 18, 19, 20, 21, 2
2, 23, 24 Conductor magnet 16 Magnet mounting ring 51, 52 Nonmagnetic electrode 53, 54 Nonmagnetic insulating film 55, 56 Nonmagnetic silicon carbide film 57, 58, 59, 60 Terminal 61, 62 Non-magnetic electrode 100 Electromagnetic field 101 Range through which ion beam passes 102 Line of electric force 103 Line of magnetic force

Claims (4)

[Claims] 1. An electronic device comprising an electrode for forming an electric field and a magnetic pole or a magnet for forming a magnetic field, and performing mass / energy separation of charged particles in an electromagnetic field space in which an electric field and a magnetic field are orthogonal to each other. An E × B apparatus, wherein the magnetic pole or the surface of the magnet facing the electromagnetic field space functions as an electrode for forming an electric field. 2. The method according to claim 1, wherein a quasi-conductive film is provided on a surface of the magnetic pole or the magnet facing the electromagnetic field space so that the surface of the magnetic pole or the magnet facing the electromagnetic field space functions as an electrode for forming an electric field. The E × B apparatus according to claim 1. 3. A magnetic pole or magnet for forming a magnetic field,
A plurality of magnetic poles or magnets each electrically insulated are arranged in the same magnetic pole direction, and a plurality of magnetic poles or magnets respectively electrically insulated such that different magnetic poles face the plurality of magnetic poles or magnets. 2. The E.times.B apparatus according to claim 1, wherein the apparatus is arranged side by side in the same magnetic pole direction, and a plurality of opposing magnetic poles or surfaces of magnets function as electrodes for forming an electric field. 4. A plurality of electrically-conductive magnetic poles or magnets, each of which is electrically insulated, are arranged point-symmetrically, and an electric field and a magnetic field are orthogonal to a central portion where the plurality of conductive magnetic poles or magnets face each other. An E × B apparatus for forming a field space to separate mass and energy of charged particles, wherein the plurality of conductive magnetic poles or magnets which also function as electrodes for forming an electric field have a surface facing an electromagnetic field space. The potential is adjusted so as to have a linear relationship between the deflection voltage and the astigmatism correction voltage, or a linear relationship between the deflection voltage, the astigmatism correction voltage and the convergence voltage, in addition to the mass separation voltage. An E × B apparatus characterized in that: