TW201528331A - C-shaped yoke coil mass analyzer apparatus for separating desired ion species from unwanted ion species in ribbon ion beams of arbitrary breadth - Google Patents

Abstract

The present invention is a C-shaped yoke-coil assembly which operates as a markedly improved mass analyzer device; and is able to achieve at least one identifiable modification (such as an effective separation of dissimilar charged ion species) in an adjacent traveling ribbon-shaped beam. The C-shaped yoke coil assembly offers a commercially useful resolving power; is far easier and less expensive to manufacture; and is quickly positioned, aligned, and operated in comparison to conventionally known mass analyzer devices.

Description

C-type yoke coil mass analyzer device for separating desired ion species from unwanted ion species of any width of a ribbon ion beam [related application]

The present invention was first filed on December 20, 2013 with the U.S. Patent Office as U.S. Provisional Application No. 61/963,986, and the legal benefit of this prior application is claimed herein.

The present invention is filed on Feb. 27, 2012, entitled "Mass Analyzer Apparatus And Systems Operative For Focusing Ribbon Ion Beams And For Separating Desired Ion Species From Unwanted Ion Species In Ribbon Ion Beams", US Non-Temporary Application No. 13/ Part of the continuation of 385,618, all of the legal benefits and benefits of this earlier patent application are expressly claimed in this document.

The present invention relates to a magnetic mass analyzer that is Used to stream high current ribbon ion beams in various systems and applications. The ribbon beam poses a unique problem for the analysis magnet designer compared to a beam that is used in a mass spectrometry system with a cylindrical beam. All of these mass analyzer devices are often used to separate a desired ion beam from an unwanted ion beam, then present within the ribbon ion beam, and the ballistic path of the moving ion beam ( The trajectory pathways) deflect and change and provide a focus of the ions within the moving ion beam. In all cases, the skew and focus are dependent on mass, energy, and charge of the ions.

The first analysis of the ribbon beam was in the Calutron system for uranium isotope separation in the Manhattan project. The ion source is immersed in a uniform magnetic field that deflects the extracted ribbon beam 180 degrees and bends it into its narrow (width) dimension plane. The magnetic field is aligned with its wide dimension. Subsequent systems (their ion sources are moved away from the analysis magnet for a distance) use different designs.

The use of magnetic mass analyzer devices in ion implantation systems and methods to alter the characteristics and characteristics of ribbon ion beams (also referred to as 'sheet beams' or 'belt beams') has become very It is common and routine, and is therefore particularly well known. It is apparent from the conventional practice in the related art that the preferred known magnetic devices used for this purpose are disclosed and described in the individual configurations listed below: U.S. Patent No. 4,578,589 (Aitken); 5,126,575 (White); 5,350,926 (White et al.); 5,834,786 (White et al.); 6,162,262 (Aoki); 6,498,348 (Aitken); 7,112,789 (White); No. 8, 263, 941 (Benveniste); No. 8, 723, 135 (Glavish); U.S. Patent Publication No. 20120235053 (White) - the entire contents of each of which are hereby incorporated by reference.

Technical considerations

In order to implant ions in large substrates (such as flat panel displays and solar panels), it is desirable in the industry to purify broadband ion beams by mass selection. In the context of these system applications, the most important feature for selecting a mass analyzer is the ability to increase in size; in particular, from linear extension on the breadth scale to any arbitrary The ability to choose the scale that can be measured. Another very important feature of this device is its ability to perform its high resolution resolution separation function without any magnetic components aligned with the major lateral dimensions of the beam (i.e., the width dimension).

The following is provided for informational and comparative resolution purposes only: a low intensity magnetic field is conventionally in the range of about 0 to 0.05 T; a moderate intensity magnetic field is typically in the range of about 0.05 T to 0.5 T; And a high-intensity magnetic field is traditionally in the range of about 0.5T to 1.2T; and higher magnetic fields are beyond the scope of this article because of the available Ferromagnetic materials are saturated at 1.8T, which provides a limit beyond which complexity and cost can be excessively increased.

Mass spectrometry is typically performed for ion beams having energies between about 5 keV and 100 keV, even when the final desired ion energy is above or below this range. The magnetic field required to perform this work is inversely proportional to the charge and radius and is proportional to the mass of the ion and the square root of the energy. The ampere-turns in the electromagnet winding are proportional to the distance (which is measured in a direction perpendicular to the direction of the movement of the ions that establish the magnetic field and the direction of the skew plane). This distance must be greater than the dimensions of the beam. Typically, a conventional ferromagnetic yoke is used to minimize this ampere-turn number requirement for controlling the shape of the magnetic field and thereby accurately controlling the focus quality of the magnetic field and stray magnetic field )minimize.

The use of this ferromagnetic yoke requires at least 80,000 amps-turns to produce a Tesla magnetic field at a distance of 100 mm between the two poles. This magnetic field is sufficient to deflect a commercially interesting ionic species and energy in a path having a radius of approximately 300 mm. Therefore, generating a high-intensity magnetic field across a large gap and spatial distance (for example, 1 to 2 meters) requires sufficient power and cooling, which may be greater than 1 million amps.

Thus, as clearly stated in the published technical article: when the mass analyzer device is sized to accommodate a larger arbitrary beam width dimension and the direction of the magnetic field remains and the beam Alignment in the width direction (which facilitates high resolution power and the band When the beam has a high aspect ratio, the number of ampere turns in the electronic coil necessary to generate the desired magnetic field strength in the device is significantly increased, and the device becomes larger on three scales, And there is a tendency for magnetic flux to leak further from the device; and both the overall size and weight of the device are greatly increased and become extremely inconvenient, to the extent that it is not only difficult to transport; and it is impossible to transport complete components. Things. See, for example, Alexeff, IEEE Transactions on Plasma Science 07, 1983; Banford, Transport of Charged Particles, Spon, 1966; Livingood, Optics of Dipole Magnets, AP, 1969; Septier and Septier, ed. Focusing of Charged particles, AP, 1967; and Stanley Humphries Jr., Charged Particle Beams, Wiley, 1990.

Any of these events are extremely undesirable and should be avoided as much as possible. However, in many mass analyzer devices, most, if not all, of these unfavorable or unwanted events occur normally and repeatedly, thus separating the masses in large sizes for mass separation. There is still a need for different ionic species within the beam.

A system that has been successfully commercialized, with a magnetic field and a narrow band beam alignment (see U.S. Patent Nos. 5,350,926 and 5,834,786), which reduce the ampere-turn requirements and can be extended to 300 mm and 800 mm, respectively. The width is wide. In the first of these two examples, two magnets are required to produce a 300 mm wide beam with a resolution of about 80, and in the second, a single magnet is used. The 800mm wide beam, but the resolution is only 5.

Another technical information point should also be proposed herein: the focusing of the ion ballistic path typically occurs when a magnetic field gradient is applied to produce charged particles. An important prior art example of this result is a conventional example of focusing that occurs between the oblique entrance and exit magnetic poles of a bipolar magnet, i.e., the focus occurs in a fringe field. This focusing effect is described in detail by Enge in technical articles in several publications [see, for example, Septier and Septier eds., Facusing of Charged Particles, Chapter 4.2, Vol 2 p. 203, AP (1967)]; and also by AP Banford, [see for example, Transport of Charged Particle Beams (Spon, 1966)].

A brief historical overview of related prior art devices

In magnetic field beam bending or focusing devices, the deflection of charged ions is proportional to the charge value of the ions and inversely proportional to the ion momentum.

Prior art Figure 1 (which is taken from U.S. Patent No. 5,126,575) shows how a strip beam (by a particular ion source shape) is focused such that its major dimension (which is referred to herein as Its width is focused to have a minimum dimension in the middle of the gap between the bend and the analysis magnet; then, it is then diverged again to provide a large-scale, high aspect ratio analyzed beam beam . Unfortunately, it is known that this very high current density at the center of the analytical magnet is a source of major beam instability, as further described in the examples below.

Prior art Figure 2 (which is taken from U.S. Patent No. 5,350,926) shows how a strip beam is transmitted such that its width dimension is parallel to the width of the pole; therefore, the gap between the poles can be The width of the beam is a quarter or less. However, the large aspect ratio of the desired beam is recovered only by subsequently passing the beam through a second largest magnet whose primary function is to expand the expanded beam beam. Focus in parallel. This '926 patent discusses why it is desirable to have a low current density in a strong magnetic field to avoid plasma instability, which limits the maximum current density to a substantial maximum. It should be noted that the current density at the focal point between the magnets may be 200 to 1000 times greater than the current density at the center of the magnets - but the worst beam degradation may occur within the magnets. . This system has been commercially mass-produced, in part because of its success in avoiding this current limitation; however, even for a 300mm beam, the weight of the magnet weighs 10 tons and the system does not easily expand to larger The beam.

Prior art Figure 3 (which is taken from U.S. Patent No. 7,112,789) shows how a ribbon beam is encoded in its narrow-scale direction while still expanding in its wide-scale direction; Resolving power. In this example, a very large coil with a complex three-dimensional shape is required (because of the large magnetic pole gap) to wrap around the tall ion beam at the entrance and exit of the magnet. This approach has so far been successful in the case of a beam width of up to 1.2 m, but further expansion has become very heavy and very expensive. In addition, U.S. Patent No. 6,162,262 describes a "window frame" magnet that is used in a similar manner. Iron; but it suffers from the problem of larger stray magnetic fields, which require a lot of ferromagnetic material in the yoke.

Prior art Figure 4 (which is taken from U.S. Patent No. 8,723,135) has similar coil bending above and above the ends of the beam; has a large bend radius which is three to the beam height Four times; and has been used in larger sizes. But its weight exceeds 100 tons for large commercial sizes, which creates considerable difficulty; and the resolution is much smaller than 10.

In U.S. Patent Application Serial No. 13/385,618 (U.S. Patent Publication No. 20120235053), several other methods are inspected, which generally use the aberrations of the magnetic lens (the beam is eccentrically transmitted in the lens) to separate the differences. Type of ion. These methods achieve low resolution; but have the advantage of small size.

Many of these prior art devices have been successfully used to reach certain sizes. However, as the beam size has grown, it is clear that the required power is increased faster than the linear ratio of the beam size; the aberration is increasing by the square of the beam size; and the weight is increasing It is faster than the square of the beam size, in some cases the cube of the beam size is increasing, and the resolving power achieved is reduced in most cases.

Current outlook and needs

Thus, in today's technology, for a measurable width dimension capable of a moving ribbon beam (ie, its main lateral direction) The scale) is arbitrarily extended to any desired useful size (ie, a current size variation of about 150 mm to 3000 mm or more) to separate unwanted ion species from the ion beam and There is still a high demand for the use of an operable magnetic analyzer device that is removed.

Thus, in today's technology, an unwanted ion can be separated from a desired dopant or other treated ion species beam in a ribbon ion beam having a width greater than about 1 meter. There is still an unmet need for a variety of devices that utilize sufficient resolution to, for example, separate P ⁺ from BF ⁺ without using more power than 100000A-t, and the coverage area of the beam system ( The footprint) is 1 to 2 square meters instead of 10 to 20 square meters, and the total weight is less than about 10 tons, making transportation and installation using traditional lifting tools simple and easy.

Furthermore, there is a continuing need for a magnetic field generating device whose magnetic field profile does not change in the direction of the dimension that is expanded along the width dimension, i.e., during beam focusing or skewing, along the main transverse dimension of the beam. Systematic changes; and few, if any, inincacencies or errors introduced by artifacts produced by the operating device are introduced.

In any case, as far as is known, none of these important goals and desired results have been successfully achieved by today's mass analyzer devices.

The invention has several aspects.

The first aspect is a mass analyzer device adapted to apply a wanted beam of a desired beam of ions (having an energy value ranging between about 5 and 80 keV) from unwanted magnetic ions of different magnetic rigidity. (ie, ions having meaningfully different masses and/or energy and/or state of charge) separated by the moving ribbon beam passing through the adjacent device, the mass analyzer device comprising: a substantially C-type a yoke coil assembly that is disposed adjacent to a path of movement of the ribbon beam and thereby spans a width dimension of the adjacent ion beam, the substantial C-yoke coil assembly comprising: a form and scale a tunnel-shaped yoke having (a) having a C-shaped cross-section that surrounds more than 180 degrees and typically 190 to 210 degrees, and which surrounds three sides of a tunnel-shaped recess and is uniform on a straight line Extending to each end of the two separate ends, (β) has two identifiable solid wall arm members as tunnel side faces and a solid central bridge segment, (γ) providing two separate arm face surfaces, It has a clip ranging between about 150 and 175 degrees (included angle), and (δ) are made of at least one magnetic metal material; and at least one wound coil disposed on the tunnel yoke, wherein each of the wound coils (i) provided is a runway An obround loop that is wound by a multi-turn conductor and includes parallel straight length sections of two conductor windings And two separate curved ends, wherein each of the linear length segments has a length greater than a width dimension of the moving ribbon beam, and each curved end is bent 180 degrees and is engaged with the linear length segments, Ii) extending around and surrounding the yoke, (iii) being arranged such that one of the two linear length segments is located within the tunnel space of the yoke, and the other linear length segment is located outside the yoke, (iv) Generating an on-demand magnetic field that is emitted at right angles from the surface of the yoke, the spatial regions in which the plurality of magnetic fields are directed are thereby generated and arranged in a continuous series, the plurality of magnetic fields being The volume, magnetic field strength, and directional effects of the oriented spatial regions are generally sufficient to achieve substantial changes in the adjacent moving ion beam.

A second aspect of the present invention provides an operating system adapted to change the direction and convergence of a contiguous moving strip of ion beam selected arbitrarily, the operating system comprising: a moving strip beam, Included in at least one desired ion species and at least one unwanted ion species, wherein the ion beam has a width dimension pre-selected and the size is fixed from less than 100 mm to greater than 3000 mm, the thickness dimension of the ion beam being Preselected and dimensioned from about 1 mm to 10 mm, and the thickness of the ion beam is only divergent by about ±2° or more; a mass analyzer device constructed to form a substantially C-yoke coil assembly, and The moving path of the ribbon ion beam is adjacent and thereby spans the width dimension of the adjacent moving ion beam, the substantial C-yoke coil assembly comprising: a tunnel-shaped yoke having a shape and a dimension, the (α) having a C-shaped cross section that surrounds more than 180 degrees and typically 190 to 210 degrees, and which surrounds three sides of a tunnel-shaped recess and Uniformly extending in a straight line to each end of the two separate ends, (β) has two identifiable solid wall arm members as tunnel sides and a solid central bridge segment, (γ) providing two separate An arm face surface having an included angle ranging from about 150 to 175 degrees, and (δ) being made of at least one magnetic metal material; and at least one wound coil disposed on the tunnel yoke, wherein Each of the wound coils (i) to be disposed is a racetrack-type obround loop which is wound by a multi-turn conductor and includes parallel straight length sections of two conductor windings and two separate loops. a curved end, wherein each of the linear length segments has a length greater than a width dimension of the moving strip beam, and each curved end is bent 180 degrees and engaged with the linear length segments, (ii) extending around And surrounding the yoke, (iii) is set such that two straight length sections One is located in the tunnel space of the yoke, and the other straight length section is located outside the yoke, (iv) can generate an on-demand magnetic field, which is emitted from the surface of the yoke at right angles, A spatial region in which a plurality of magnetic fields are directed is thereby generated and arranged in a continuous series, the volume, magnetic field strength, and directional effect of the spatial region of the magnetic field being oriented The upper system is sufficient to achieve substantial changes in the adjacent moving ion beam, and a current source that is in electrical communication with the oblong coil.

1‧‧‧Bridge section

13‧‧‧ surface

7a‧‧‧arms

7b‧‧‧arms

15‧‧‧ surface

2‧‧‧Electromagnetic coil

52a‧‧‧Line length section

52b‧‧‧Line length section

2a‧‧‧Electromagnetic coil

2b‧‧‧Electromagnetic coil

10‧‧‧C type yoke coil assembly

113‧‧‧ Space area

115‧‧‧ Space area

112‧‧‧Intermediate space area

3a‧‧‧ stick

3b‧‧‧ stick

4‧‧‧ stick

50‧‧‧ traversely mounted coils

112b‧‧‧ middle volume area

113b‧‧‧End Space Area

The present invention may be more readily understood and appreciated when in conjunction with the accompanying drawings, wherein: prior art Figure 1 shows a proposed and discarded system that uses a convergent strip beam with an analytical magnet The center of the field region has a minimum width that expands to produce a high aspect ratio broadband beam; prior art Figure 2 illustrates a conventionally known device using two magnets, the first magnet of which is borrowed The strip beam is analyzed by deflecting the strip beam onto a plane of its width, the second magnet of the magnets allowing the strip beam to expand prior to focusing to become a high aspect ratio Parallel strip beam; prior art Figure 3 shows a conventionally known White and Chen magnetic analyzer that uses a 'bedstead' coil and an optional expansion profile to analyze a high aspect ratio High current strip beam; prior art Figure 4 shows a conventionally known Glavish magnet analyzer for very high ribbon ion beams; Figure 5a shows a side view of the substantially C-yoke coil assembly of the present invention and Figure 5b shows a perspective view thereof; Figures 6a and 6b show side views of the tunnel yoke with an adjacent moving ion beam; Figure 6c shows the tunnel with an adjacent moving ion beam A cross-sectional view of a yoke illustrating the ability of the yoke coil assembly to deflect and refocus a moving trajectory of an adjacent ion beam; Figure 7 shows a band-shaped moving ion that is altered, deflected, and focused by the present invention. a plurality of perspective views of the molded shape of the beam; FIG. 8 shows a detailed perspective view of the electrical coil traversed within the substantially C-yoke coil assembly having the auxiliary magnetic field shaping bar, wherein an ion beam passes through Between the yoke and the auxiliary bars; Figure 9a shows a cross section of the substantially C-yoke coil assembly, wherein the magnetic flux lines are shown and different regions of the overall magnetic field orientation are shown; Figure 9b shows and three auxiliary magnetic fields shaping A preferred embodiment of the substantially C-yoke coil assembly incorporating the rods exhibits magnetic field concentrations in three consecutive regions through which the beam can traverse; FIG. 10 is a graph showing the magnetic field along a a line diagram of the Y-direction component and the Z-direction component of the projection path of ions on the YZ plane, wherein the magnetic field regions from Figures 9a and 9b are labeled; and Figure 11 shows an embodiment of the C-yoke coil analyzer, In this parser It is extended to the vacuum ring.

The present invention is a substantially C-yoke capable of achieving at least one desired change (e.g., efficient separation of charged ion mass) in any contiguous moving strip beam of any fixed width dimension selected arbitrarily. Coil assembly. The substantial C-yoke coil assembly is a mass analyzer device that is much lighter than previous devices of the same capability; It is easier and cheaper to manufacture and be enlarged in the beam width direction for handling very broad but thin strip beams; and can be mounted, aligned and operated faster than conventional conventional devices.

The value of a mass analyzer component with high resolution

1. Conventionally, in the technical field of the invention is conventional and the operation in many cases, especially in commercial applications, the P ⁺ ions from the P ⁺⁺ ions and P ₂ ⁺ ions, and from a Separation of some other positively charged contaminants is necessary; and it is often necessary to separate B ⁺ ions from B ⁺⁺ ions and from F ⁺ ions. A more convincing example is the separation of ²⁷ Al ⁺ from ³¹ P ⁺ , and the separation of ¹⁹ F ¹¹ B ⁺ (30 amu) from ³¹ P ⁺ may be the most important conventional example, from a previous boron The trace gases of the implant contaminate a subsequent phosphorus implant that is applied to the same ion implant. A high resolution capability greater than 31 is necessary in this illustrative example.

A system for transporting a beam through a resolving aperture that transmits only the desired ion species is defined as transporting the ion beam from a first misaligned position (ie, through a hole in the ion transport) 50% on one side of the maximum) physically moves to a second misaligned position (ie, 50% of the ion transport through one hole is on the other side of the maximum) required for the change in ion mass (or energy) Reciprocal of fractional. This is abbreviated as M/ΔM FWHM, where FWHM is an abbreviation for Full Width at Half Maximum. It usually controls the energy by making very fine changes to the beam accelerating voltage, or The beam flow leaving the magnetic analyzer performs a fine change and measures the transmitted beam current for measurement.

Therefore, a fairly high resolution is important to achieve efficient separation of complex charged particle mixtures, as different kinds of mixtures will always contain a large amount of charged background ions. In these cases, a device with higher resolution is separating and blocking unwanted ion species (the difference in mass between the mass and the desired ion species is small) and does not detect or separate unwanted ion species at all. There is a substantial difference between the two.

For example, in order to detect and separate B ⁺ ions from B ⁺⁺ ions and from F ⁺ ions, a mass analyzer device would require a minimum resolution of about 2. However, in order to achieve high quality separation of the desired charged particles with reliable removal of unwanted ionic contaminants, it is typically necessary to significantly increase the resolution to at least 20. Similarly, in order to effectively detect, separate, and isolate BF ⁺ ions from P ⁺ ions, it is generally desirable that the mass analyzer device has a much greater resolution than 31; and in these operating situations, the resolution Devices with a capacity of 40 or greater are the most popular and highly desirable. Therefore, the higher the resolution of the mass analyzer device, the better the quality of the ion species separation.

In addition, the efficient coupling of this high resolution mass separation device to a high current linear ion source will have significant advantages and advantages for ion implantation of large substrates such as flat panel displays and solar cells.

2. Therefore, a particularly groundbreaking feature provided by the present invention The ability to effectively detect and separate similar but identifiably different ion species from a common contiguous strip beam simply by extending the device over pre-selected dimensions. Moreover, in the foregoing, it will be appreciated that this particular ability is neither a small achievement nor a trivial feature.

The true resolution capability of high current implant equipment for tantalum wafers in the market is based in part on beam energy and current in the range of 20 to 60. The present invention can normally provide a resolving power of about 40 while being capable of extending 10 times the beam width and 10 times the beam current than conventional implanters. Precision mass spectrometers operating at low currents can have much higher resolution (up to 500 or higher), but conventional implanters for flat panel displays typically achieve a resolution that is slightly higher than 3.

Existing implanters for very large flat panel displays use large-width multi-tip ion sources with porous extraction systems (Dohi et al. IIT 2006 (2006) 417-420, Matsumoto et al., IIT 2012 (2012), 324 -327). They use a unique bipolar bending magnet that is quite traditional for mass resolution, which is traditionally bent at an angle of 60 to 90 degrees. The width (main dimension) of the plasma beam is between 1 and 2.2 meters, which is 10 to 20 times the thickness of the beam (about 100 mm) and their bending radius is increased to several Rulers are used to keep their scale proportional to the smaller scale of conventional devices. They achieve a resolution of about 5. This is not suitable for, for example, separating phosphorus ions from PH ⁺ ions, separating boron ions from carbon ions, or separating BF ⁺ ions from P ⁺ ions.

Thus, all embodiments of the present invention will provide a high resolution capability ranging from about 15 to about 30 in a normal and reliable manner; and with this most desirable feature and unique capabilities, a good quality of detection and With a significantly improved separation of one or more individual ion species, the plasma species appear to move together in a mixture of charged particles in a contiguous ribbon beam of arbitrarily selected width width, thus being purer The dopant species can be implanted into the polycrystalline germanium film layer.

II. The capabilities and features provided by the substantial C-yoke coil assembly as a whole

The open three-sided yoke assembly constituting the present invention can be used in many alternative applications and can be used to achieve a variety of different results. In a preferred embodiment, the yoke coil assembly is predominantly in the form of a C, wherein the "C" configuration is an open loop that is bent about 200 degrees. The assembly may additionally be presented in a different form, which is more or less rounded in shape; but in all examples, the yoke encircles three sides of a central tunnel pocket, the central tunnel pocket being The oblong electromagnetic coil or the linear length conductors of the coils are occupied.

The range of versatility of the overall capabilities and characteristics of the present invention thus includes all of the following:

(i) The open yoke assembly is capable of unambiguously changing the angle of the moving ion beam from its incoming or initial ballistic deflection, which is typically greater than about 8 degrees and no greater than about 25 degrees.

(ii) the open yoke assembly is capable of explicitly at least one (and sometimes several) of the desired ion species from one or more unwanted Ion species are separated from impurities.

(iii) The open yoke assembly is capable of explicitly focusing the charged ion beam of the moving ion beam in the Y-Z plane.

(iv) The open yoke assembly is capable of clearly separating B ions from C ions and separating P ions from PH ions.

(v) The open yoke coil assembly is capable of performing the above-described actions explicitly for ion beams of a width of 1 to 2.5 meters, even without substantial limitations.

(vi) The open yoke coil assembly can clearly target a mass-energy product ion beam having a mass of 2.5 amu. MeV (in other words, up to 80 keV phosphor) within a distance of up to 1 meter. Achieve this quality separation.

(vii) The open yoke assembly can achieve all of the above actions in a clear manner as a one-piece device weighing less than about 10 metric tons.

Moreover, on the whole, the unique characteristics of not less than four items of the present invention must be properly recognized and truly understood, and they are:

First, the substantial C-yoke assembly constituting the present invention is a single integral mass analyzer assembly that operates independently and has a complete function and is sufficient for the purpose of altering a moving charged particle beam. The beam will pass spatially adjacent thereto, i.e., without the use of a pair or more of the aforementioned devices, before a high intensity magnetic field sufficient to achieve its intended purpose can be produced.

Second, the volumetric region of the entire magnetic field produced by the substantial C-yoke coil mass analyzer assembly and the variable intensity are The arbitrarily selected fixed-width-scale ribbon ion beam is sufficient in quantity to traverse it, that is, the spatial region of the magnetic field generated by the yoke coil assembly and extending at right angles in an overall size and Both of the magnetic field strength values are suitable for achieving effective separation of different ion species and for achieving (preselected mass) charged ionic particles, and then moving in a beam.

Third, the entire magnetic field produced by the substantial C-yoke coil mass analyser assembly will always exhibit some minimal features, including: (i) a magnetic field extending at an angle that is large enough to cover and evenly spread over the moving shot. (ii) a magnetic field of a predetermined intensity (the magnetic flux line is always flat in the YZ plane), and the magnetic field profile extends uniformly along the X-axis direction; and (iii) along the The effective zero value of the magnetic field component of the X-axis direction (width, traverse direction) of the moving ion beam.

Fourth, the substantial C-yoke coil assembly as a whole is by no means operational in operation and never operates like a solenoid, ie a charged ion beam beam will not enter the assembly at any time. Within the spatial volume of a coil that is placed, it will never pass through the material of a coil of the device that is placed. Conversely, the yoke coil assembly as a whole and the moving ion beam are juxtaposed and disposed adjacent to the moving ion beam. A magnetic field enhancement rod that is optionally disposed on the opposite side of the beam from the yoke coil is primarily a passive member that increases the strength of the magnetic field at a given coil current, but it does not Play its important role.

III. Structure of the substantial C-type yoke coil assembly

The present invention can be best understood by considering an operating system in which a ribbon ion beam of a plurality of ion species is moved a predetermined distance in a forward moving direction. In this operating system, the moving ion beam can be identified and characterized using a right angle coordinate system.

It is common to use a curvilinear Z-axis based on a reference ion trajectory in an ion beam system. However, because the beam is bent at a relatively small angle (eg, 16 degrees), this method is not used here for simplicity; and the z-axis represents the direction of movement of ions into and out of the device. Average (mean).

Thus, the Z axis is an approximately average predetermined moving direction of the ion beam; and the Y axis is the average direction of the narrow thickness dimension of the beam; and the X axis is the direction of the beam width dimension of the beam. Therefore, the space and direction of the right angle coordinate system are fixed.

Right angle coordinate system of the operating system

The ion source emits the ion beam at a small angle of about 5 to 15 degrees with respect to the Z axis, which has a motion component in the positive Y-axis direction. However, the intention is that after the beam traverses the device, the beam will have an opposite component of motion in the Y direction; therefore, the Z-axis direction is where ions enter and exit the C-yoke coil assembly structure. The average of the directions.

The main linear traverse dimension of the beam is its fixed width dimension, and its magnitude can be arbitrarily selected from less than 100 mm to more than 3000 mm; and this width dimension is always parallel to the X axis.

In contrast, the minor traverse dimension of the beam is its thickness dimension, and the magnitude of its size typically varies from about 3 mm to 30 mm or more when the ion beam diverges, and will generally align with the Y axis. However, if the ion beam is deflected by about 16° in the negative Y-axis direction while traversing the mass analyzer device, the Y-axis is arbitrarily selected (as shown in the figure), the shot The Y-axis length of the beam is its actual thickness divided by the cosine of the direction of movement of the beam and the angle between the Z-axis.

In each of the examples, it is contemplated and contemplated that the moving ribbon beam will contain at least one (and sometimes several) of the desired ion species, as well as one or more unwanted ion species impurities. . When the strip beam is extracted by its ion source, the strip beam has a typical thickness scale of 2 to 5 mm, but diverges by ±2° on this scale (but this value depends on and Many factors related to the construction of ion physics and thermal expansion related to the problem). The size of the primary width dimension for the beam can range from about 80 mm to greater than 3000 mm. These right angle coordinates are more precisely described below as desired.

Construction of the yoke coil assembly

Within this exemplary right angle coordinate system, the mass analyzer apparatus of the present invention is purposefully used. In this case, the present invention is as follows A separate yoke coil is presented that includes two main components: a tunnel yoke; and at least one laterally mounted electromagnetic coil disposed thereon. A perspective view of the entirety of the present invention is illustrated in Figure 5b.

As shown in Figure 5, the tunnel yoke typically looks like a three-part symmetrical support structure. As seen in the figure, the tunnel yoke: (α) has a C-shaped cross section that surrounds more than 180 degrees and typically 190 degrees to 210 degrees, and which surrounds three sides of a tunnel-shaped recess, and Uniformly extending in a straight line to each of its two separate ends, (β) has two identifiable solid wall arms as a tunnel side and a solid central bridge, (γ) providing two The separate arm face surfaces are provided with an included angle ranging from about 150 to 175 degrees, and (δ) is made of at least one magnetic metal material or metal alloy material.

Typically, the tunnel yoke is fabricated or cast from iron or mild steel or other (more expensive) magnetic materials. It can be manufactured in a single piece; or it can be assembled from two arm members 7a and 7b and a central connecting bridge 1. The individual arm members 7a terminate in a face surface 13; and the separate arm members 7b terminate at the face surface 15.

In contrast, the electromagnetic coil 2 is a racetrack-type loop winding made of an electrical conductor; and becomes part of the tunnel-type yoke structure, which is a portion of the coil that occupies the tunnel pocket, as shown in FIGS. 5a and 5b. Show. The coil 2 typically comprises parallel straight length sections of two wound electrical conductors 52a and 52b, the linear length of each linear length section being greater than the linear length of the width of the moving strip beam, a section (52b) occupying at least a portion of the tunnel pocket of the yoke; Two curved ends, each curved end is bent 180 degrees and seamlessly engages the linear length sections 52a and 52b into a shape known as an 'obround'.

Although a discernible coil is functionally sufficient, the two smaller-sized electromagnetic coils 2a and 2b may be replaced, as shown in FIG. 8, each coil of the two coils respectively surrounding the tunnel-shaped yoke. One of the side arms of the two side arms, and the straight length section of each coil is seated within the yoke tunnel pocket. These two coil configurations have been discovered to reduce the magnetic field generated in the non-productive region; however, it does not affect the basic principle of operation of the yoke coil assembly.

The current is selectively passed through the electromagnetic coil or the electromagnetic coils from any conventional and controllable source, and a magnetic field extending at an angle is thereby generated, which not only surrounds the current carrying conductor material; The ferromagnetic material of the yoke structure is shaped to become gathered at the separated ends near the two exposed wall surfaces 13 and 15, whereby the surface of one arm end becomes 'North' according to the flow direction of the current The surface of the pole and the other arm end serves as the 'South' pole. A high intensity magnetic field is created by the electromagnetic coil between the two arm face surfaces 13 and 15, which deflects the beam in a complex three dimensional path as described below.

The assembly is over the entire width dimension of an adjacent moving ion beam and Positioning across the width of the width

In each used example, the C-yoke coil assembly will be traversed as a magnetic analyzer unit that spatially passes over and over the entire width dimension of a moving sub-beam that is disposed adjacently The ground spans the width of the width.

As shown in Figures 6a and 6b, the adjacent beam system is initially deflected in the negative X-axis direction; then deflected back in the opposite direction to become an S-curve, so the net velocity in the X-direction is back. To zero. However, as a result, the moving path of the beam becomes significantly deviated in the X direction, which is about 200 mm in this example.

Therefore, the X-axis length of the C-yoke coil assembly must be the entire fixed width dimension of the beam; plus about 200 mm of the offset; plus a generous extra amount to ensure that the magnetic field is uniform to the beam edge It is not distorted by the presence of the edge of the magnetic field.

In order to achieve this, the C-yoke coil assembly 10 will be traversed across the path of movement of the adjacent ion beam and then moved in the Z direction with a small Y motion component; and through this lateral arrangement, The appropriately preselected dimensions of the yoke coil assembly will completely bridge and span the entire width dimension of the adjacent moving ion beam, including the offset distance caused by the action of the S-type deflection.

The spanning settings and spatially adjacent lateral placements in this plan are explicitly illustrated in Figures 6a, 6b, 6c and 8, respectively. In particular, Figures 6a and 6b show that the yoke coil assembly of the present invention is traversed across the entire beam width dimension as the adjacent ion beam moves in the Z-axis direction. And the case of crossing it; and Figures 6c and 8 illustrate the ability of the C-yoke coil assembly disposed at the bridging position to deflect the ballistics of the adjacent moving ion beam.

Figure 7 is a set of different perspective views of a very wide strip beam showing the shape as it is deflected and focused by the C-yoke coil assembly. These figures are used to show the complex three-dimensional shape of the path of the beam. These drawings were generated based on the results of the computer program TOSCA sold by Cobham.

It is important to understand the single wound coil of Figure 6 or the plurality of wound coils clearly shown in Figure 8 surrounding the ferromagnetic material of the tunnel yoke; and it is important to almost fill the central space surrounded by its arched structure. of. The single or multiple electromagnetic coils are not in any operating environment, even if they are surrounded or surrounded by the moving ion beam.

It will also be appreciated that the tunnel yoke and solenoid can be placed in the ambient air atmosphere. Therefore, in the embodiment shown in Figures 6 and 11, only the surface of the two arm members with the 'North' pole and the 'South' pole must be exposed to a vacuum environment; and by inserting a thin vacuum It is also entirely possible that the wall keeps the entire tunnel yoke outside of the vacuum environment.

It should also be noted that the solenoid is only placed on one side of the adjacent moving ion beam (see Figures 6 and 11). No magnetic field component is applied along the main width of the ion beam. This is completely unique and different from all other conventionally known devices in the field.

Skew of an adjacent moving ion beam

Those skilled in the art to work properly understand and recognize that the C-yoke coil assembly produces a shape of the detailed shape of the magnetic field in the contiguous spatial region through which the parallel ion beam will pass.

Referring first to the illustration of Figure 5a, the adjacent moving ion beam will first pass adjacent the arm face surface 13 of the tunnel yoke; then through a central intermediate space region; then will pass immediately adjacent the arm face surface 15; Continue to leave the device. It will be recalled here that a magnetic field can deflect an ion in a direction perpendicular to the direction of movement of the magnetic field and the ion, but the imposed static magnetic field neither accelerates the ion nor Slow it down.

Referring now to the illustration of Figures 6c and 9a, the spatial region in front of the arm face surface 13 is indicated by a rectangular frame designated 113. This spatial region 113 generally depicts the direction of the magnetic field transversely through the beam trajectory; the magnetic field is oriented at right angles to the surface of the arm pole; and the magnetic field extends in the negative Y-axis direction (but tilted) About 8°). The magnetic field lines are curved; therefore, the events and results are approximate but retain substantial accuracy.

Next, the ballistic force path of the adjacent moving beam moves into the intermediate space region of the center, as indicated by the rectangle 112 in Figure 9a. Within the intermediate space region 112 of this center, the magnetic field is substantially (and evenly) aligned with the Z axis.

Finally, a third spatial region beside the pole surface 15 of the arm member In domain 115, the magnetic field is substantially oriented in the positive Y-axis direction, which is perpendicular to the pole surface; and is inclined 8° in the opposite direction to the spatial region 113.

After understanding the above-described series of skews and changes in path direction of the adjacent moving beam, practitioners of the art must now consider the effects on individual ion trajectories.

An ion moving in the adjacent beam generally moves in the Z-axis direction but has a moving path inclined by an angle β ₁ = 8 degrees in the Y-axis direction. Thus, as shown in Figures 5a and 6 (which show different views (and sometimes a complete band beam)), the ions then enter the spatial field region 113.

In this spatial region 113, the ions move evenly at right angles to the magnetic field; at this point, the ions are deflected away, entering the paper of Figure 5a, away from the viewer of Figure 5a; but in this manner and the direction of ion deflection Cannot be seen in the schema of Figure 5a. However, the direction of this ion deflection can be clearly seen in Figure 6b, the spatial region 113 is indicated in Figure 6b; and the magnetic field strength is adjusted such that in the spatial region 113, the ions are in the negative X-axis direction The upper one is skewed by an angle between about 25 and 45 degrees; and is skewed by about 30 degrees in the illustrated example.

The plasma quickly exits the spatial region 113; then enters the central intermediate space region 112 where the magnetic field is aligned in the Z-axis direction. If the plasma system moves evenly and moves in a planar path in the Z-axis direction, then they will be unbiased within this spatial region 113. However, the plasma is actually tilted The angle moves within the spatial region 113; the component of the velocity that is X-axis oriented is thus the original ion velocity multiplied by -sin 30°. In other words, in the spatial region 113, half of the initial velocity is now oriented in the negative X-axis direction.

The component of this velocity is at right angles to the Z-axis oriented magnetic field and causes a skew in the negative Y-axis direction. Again, this deflection in the spatial region 113 is not visible in Figure 6b because the ion skewing action is directed away from the viewer; however, this skew is very clear in Figure 6c. The degree of skew depends on many factors, including the actual shape of the yoke and the current in the coil.

The ions in this motion then proceed into a spatial region 115 in which the B magnetic field is at right angles to its motion; and the B magnetic field is oriented toward the face 15; and extends generally in the Y-axis direction of the system. It will be noted and appreciated that this spatial region 115 is the operational inverse of the spatial region 113. In the spatial region 115, the ions are deflected by 30 degrees in the opposite direction until they have no X-axis motion component; and the plasma is moved in the Z-axis direction by being inclined by 8 degrees with respect to the negative Y-axis direction.

This ion S skew motion is actually three-dimensional, so it is often difficult to instantiate and visualize. Thus, Figure 7 shows a number of projection perspective views of a sample ion beam for an example having a width of more than 2200 mm. This "S"-type deflection between transitions between three separate spatial regions is not abrupt, but varies very smoothly and seamlessly between each other. Thus, the above description provides an accurate and appropriate description of the average ion deflection and a correct explanation of why they occur.

Therefore, in summary, the overall skew effect on the ion ballistics and the results are:

(1) the ion trajectory is initially offset by a distance in the negative X-axis direction, which is about 200 mm in this particular example;

(2) the ion trajectory is subsequently deflected by an angle in the negative Y-axis direction, which is 16 degrees in a second specific example;

(3) If the mechanical symmetry is actually well preserved and the magnetic field strength is adjusted such that the y-direction skew is also symmetrical in the intermediate plane (ie, angle β ₁ = angle β ₂ ), then it will be in the X-axis direction. Zero skew (but there will be a deviation), and this is the intended operating condition;

(4) If the initial angle of the ballistic in the YZ plane is increased from 8 degrees to 10 degrees, then the amount of Y-axis skew experienced will be greater because the ions are closer to the yoke (especially When the space region 112 passes, the magnetic field will be longer. Therefore, if the angle is reduced from 8 degrees to 6 degrees, the amount of skew in the Y-axis direction will be small. This effect affects the beam that will be focused in the Y-axis direction; and the beam that initially diverges converges away from the region 115 in the Y-axis direction, as best seen in Figure 6c.

(5) Moreover, the deviation of the X-axis direction experienced by the ion is slightly different when the angle is changed (as seen in Figures 6b and 6c, which shows the same calculated different pattern of a large ion ballistic array) ). Therefore, if the ion beam is a long strip beam, this effect is actually not an important consideration, since a 10 mm width in a 2000 mm long beam becomes a small percentage increase. .

(6) Furthermore, for all magnetic devices used to focus the plasma beam, the skew effect is proportional to the magnetic field and ion charge; and inversely proportional to the square root of the product of mass and energy.

(7) It should be noted, however, that the three-dimensional skew now results in a significant unexpected benefit, as follows: the initial skew in the spatial region 113 follows the aforementioned rules, This means that an unwanted ion (which is 10% heavier than the desired ion) will be skewed by 5% less than 30 degrees, ie, 28.5 degrees of deflection. However, this ion will now have a smaller velocity component in the X-axis direction as it traverses the central intermediate space region 112.

Therefore, the ion is deflected by a small angle because it traverses the central intermediate space region 112; however, the amount of reduction is about 5% because the mass is increased; plus because the velocity is reduced in the X direction 5% results in a net 10% reduction in angle, which means that the ion is skewed 16-1.6 = 14.4 degrees in the negative Y-axis direction. The distance from the central symmetry plane of the C-yoke coil assembly to the focus within the beam is 500 mm in this example; and the 1.6 degree angle change represents that the unwanted ions are displaced by 14 mm. In the jargon of the mass analyzer, the mass dispersion of the system is 14/10% = 140 mm.

Moreover, because of the combination of the finite size of the beam from an actual ion source and the imperfection of focus, the beam focus is actually about 4 mm wide.

We can use this particular working example to estimate that the resolution of this device will be 140/4=35M/ΔM FWHM, as previously defined of. This means that the pair of baffles 6a and 6b in Figure 6c will provide a resolving power of approximately 35 if placed just to be tangent to the desired beam. This value is unexpectedly high for devices with a total length of only 1 meter, a skew of only 16 degrees, and the processing of such large scale zero beam.

Power consumption of the traversely mounted electromagnetic coil

The power consumed by a coil of a magnet used to analyze an ion beam (which is also dependent on design details) can be generalized in general terms: the magnetic rigidity of the ion multiplied by the magnetic pole gap of the coil magnet (between The square of the effective distance between the faces of the two arms is multiplied by the width of the magnet and then multiplied by the length of the path through the magnet. It is inversely proportional to the square of the profile of the coil. There is a trade-off between the size and weight of the ferromagnetic winding coil that is traversed on the yoke bow and the required cooling.

In the present invention, the effective magnetic pole gap distance is proportional to the thickness of the ribbon ion beam of 2 to 3 times. This calculated value is much smaller than the fixed width dimension of the beam; therefore, the practitioner can estimate the power saving benefits of the current design as described below. If the term 'aspect ratio' denoted by A is used to describe the ratio of the width to thickness of the ion beam, the magnet according to the invention has the required power compared to a conventional bipolar magnet. The reduction on is a factor of 3/A ² .

For this purpose, the practitioner must use an aspect ratio at the approximate center of the center where the thickness dimension of the beam is greatest; And the beam divergence there will raise the measurable thickness of the beam to a size of about 35 to 40 mm, a significant safety margin is needed. Thus, for a beam of 2 meters width x 50 mm thickness, the aspect ratio is 40. Moreover, the present invention requires a smaller path length, typically about 1/3 of the path length, as compared to conventional magnets capable of analyzing this wide ion beam.

Therefore, for a ribbon beam having an aspect ratio of 40, the present invention requires 1/500 of the power of a conventional magnet, assuming that the two magnets used in the coil have the same cross-sectional area. In fact, a much smaller number of coils can be used and a balance can be found between manufacturing cost and power consumption.

Use an auxiliary iron rod to change performance

In Figure 9b (which should be compared to Figure 9a), three additional iron or low carbon steel bars 3a, 3b and 4 are placed where they can change the magnetic field but do not obstruct the passage of the ion beam. These separate bars 3a, 3b and 4 have a uniform prismatic profile; and have the same X-axis length as the C-yoke coil assembly. They are also oriented and aligned with the X axis.

It will be noted that the rod 3a provides a face on the opposite side of the beam from the face 13 of the C-yoke; and the bar 3b provides a face opposite the face 15 of the C-yoke. The face on one side. The rod 4 is disposed between two separate rods 3a and 3b; and the shapes of the rods are in parallel or nearly parallel to each other. The gap between the three bars 3a, 3b and 4 is preferably uniform and will generally have exactly the same value at the opposite end of the C-yoke coil assembly.

The role of these separate sticks in one fell swoop

Their first important role is that the magnetic field in the spatial regions 113 and 115 is increased relative to the magnetic field in the intermediate intermediate region 112 of the center because of the arm face surfaces 13 and 15 (which are magnetic flux bridges). The air gap between them is greatly reduced, which is replaced by a magnetizable iron species. This result increases the amount of beam deflection that is oriented by the X-axis due to a given skew in the Y-axis direction. For a given skew in the Y-axis direction, it also reduces the need for a magnetic field in the central intermediate space region 112 because the presence of the bars increases the application to the end space region 113. The amount of X-axis motion of the beam (and corrected in the opposite direction within the end space region 115).

Their second important role after the first character above is that for a given Y-axis skew, it requires a smaller number of amps, saving power and reducing Coil size requirements.

Their third important role is that the shape of the auxiliary bars can be fine-tuned to change the focusing characteristics because the Z-axis oriented magnetic field in the central intermediate space region 112 is accurately aligned with the Y-axis coordinates. The mode change is important for the intensity and aberration of this focus. This fine tuning of the focus characteristics can be accomplished, for example, by using a 3D finite element nonlinear computer program (e.g., Cobham's OPERA/TOSCA).

Another structural format of the component

A permanent magnet or a plurality of magnets can be introduced into the C-yoke coil assembly by replacing a portion of the metal structure as an alternative construction using an electromagnetic winding coil in the assembly. A simple version of this alternative mode is to cancel the electromagnetic winding coil and replace the central arcuate section of the yoke structure with a permanent magnetic material that is magnetized along the linear length dimension of the tunnel yoke.

With regard to the electromagnetic winding coil format described above, the permanent magnetic material has the possibility of two different magnetic pole orientations, namely a 'north' pole followed by a 'south' pole or a 'south' pole, followed by A 'north' pole. These two alternative configurations do not differ substantially in terms of operation or performance; conversely, the only relative difference is that one configuration shifts the beam in a downward direction, while the other magnetic pole configuration is biased. It is inclined in the upward direction (see Figures 6a and 6b). These two pole configurations will cause a deflection of approximately 16 degrees from the pole when set for optimal focus and resolution.

The use of a permanent magnet is possible because the magnetic field integrated along the Z-axis of the beam defined in the drawing is zero, which satisfies the requirement of ʃH.dl=0. According to Busch's theory, this should mean that no angular momentum is applied to the ion beam.

IV. Representative and exemplary series of alternative embodiments

The invention can be prepared with a range of different components and constructed in a variety of different formats. However, what will be clearly understood is that these The scope of the embodiments is broad; the types of these embodiments are numerous; and the details of these embodiments are represented only by the device versions 1-3 described below.

Device version 1:

While any type of magnetic pole can be used, the description of device version 1 will consistently follow and use only a single alternating magnetic pole.

In the device version 1 format of the present invention illustrated in Figures 5, 6 and 9a, a C-yoke coil assembly 10 is disposed adjacent to the ion beam moving in the Z direction. The yoke coil assembly completely spans the width dimension of the contiguous ion beam; and when a current is passed through the traversed electromagnetic winding coil, three different and separate volume regions of the magnetic field are independently generated, The contiguous ion beams sequentially pass through each of the regions of the equal volume region in series.

The three different and separate volume regions of the magnetic field sequentially extend from the 'North' and 'South' poles at the tip of the two separate arms present within the tunnel yoke; and the magnetic field The three volumetric regions are in close proximity to one another, which allows the separate regions to merge with each other through a smooth transition zone.

Furthermore, each separate volumetric region of the magnetic field that is sequentially extended from the assembly has its own characteristics, as shown in Figure 8a. Therefore, the end volume magnetic region 113 is characterized by a magnetic field that spatially extends in a direction at right angles to the pole face surface 13.

In contrast, the second intermediate volume magnetic region 112 occupies between the pole face surface 13 and the pole face surface 15 in the middle Space; adjacent to an exposed face of the traversely mounted coil 50; and providing a magnetic field substantially perpendicular to the plane of symmetry of the assembly aligned with the Z direction, as shown in FIG.

Finally, the third end volume region 115 is a magnetic field that is substantially perpendicular to the pole face 15 but spatially extends in a direction opposite to the direction of the magnetic field appearing in the pole face 13. The magnetic field lines in the third volume region 115 are continuous; and the lines flow spatially from the pole face 13 to the pole face 15, and also from the edges of the two pole faces.

Figure 9a shows the magnetic field components in these three different and separate volume regions. In the second intermediate intermediate volume region 112, the Z-axis component "Bz" of the magnetic field is large and numerically greater than the magnitude of the Y-axis magnetic field, which passes through zero in this region 112 and is everywhere Very small. In contrast, it should be noted that in the outer two volume regions 113 and 115, the opposite is true, that is, the value of the Z-axis component of the magnetic field is close to zero, and in fact the magnetic field is initially moved in the beam. The component in the direction is still substantially smaller. In the volume region 113, the Y-axis component "By" is negatively directed and has a large value; and in the volume region 115, the Y-axis component "By" is forwardly directed and has a large value.

As described above and based thereon, by placing the stopper adjacent to the desired beam path, unwanted ion species (contaminants) in the moving beam can be desired. Or the desired ion species are effectively separated. This is particularly important in this device version 1 format to block the ion path from the traversely mounted coils from passing and supporting the arch yoke frame.

Device version 2:

The second format model version of the component is shown in Figures 7 and 8b, respectively; and includes the structure of the device version 1 format plus at least two shaped ferromagnetic bars 3a and 3b, and preferably also The third stick 4.

The magnetic field is effectively terminated at a right angle to the exposed surface of the ferromagnetic bar. These ferromagnetic bars control the shape of the magnetic field; and by occupying a portion of the magnetic circuit, they locally reduce the value of the magnetic induction H, they raise the magnetic field within the gap and change its shape. In this manner, the ferromagnetic bars 3a, 3b and 4 further save power and allow for precise focusing for a particular application or application.

As shown in Fig. 9b, in the end volume regions 113 and 115 defined by the ferromagnetic bars 3a, 3b and the C-shaped coil 1, the X-axis deflection of the plasma is strong and fairly uniform. In the intermediate volume region 112, the Y-axis deflection of the plasma will be greater due to an increase in the X-axis component from the velocity of the higher magnetic field in the end space region 113b; but between two ferromagnetic The gap distance between the rods 3a, 3b has the effect of changing the spatial variation of the z-axis component of the magnetic field as a function of the Y value. Thus, by varying the shape and/or spacing of the ferromagnetic bars 3a, 3b, the spatial variation of the magnetic field within the intermediate volume region 112 can be varied; and the sub-space changes then change the amount of Y-axis focus provided.

Even if the intermediate Y-axis skew angle is almost constant, the gap distance between the two ferromagnetic bars 3a, 3b and the rod 4 is adjusted (and The coil current is also adjusted, if necessary, to change the amount of focus. The intermediate Y-axis skew angle can be adjusted by changing the current in the coil of the assembly; and this change in current within the coil can also change the X-axis offset of the entire beam.

Device version 3:

A third formatted version of the apparatus dispenses with the ferromagnetic coils and replaces a portion of the steel structure within the yoke arch bridge by replacing the electromagnetic winding with a permanent magnet material. This change and substitution means that the magnetic rigidity of the device can no longer be adjusted quickly.

However, some adjustments by varying the spacing of the permanent magnet material members are possible over a narrow range.

However, for large-sized ion beams, the cost of charging a traversely mounted electromagnetic coil can be high; therefore, if there is an application that requires a single beam ion species, then the permanent magnet format version will It is very beneficial.

V. Summary comparison of three exemplary device versions

A summary review of the overall application and material information of the present invention is set forth below. A substantial quality and quantity of the details are provided in summary herein to enable the true advantages of the present invention to be properly recognized; and the true benefits and benefits provided by the present invention may be It is understood by the practitioners working in this field of technology.

1. When considering the present invention, the Y-axis skewing ability and Y focusing The characteristics are produced in such a way that these magnetic fields are not completely parallel to the YZ plane at all points except for the curved ends of the electromagnetic winding coils (or permanent magnets). It is possible to apply any Y-axis direction skew to the charged ion particles and then move in the Z-axis moving direction in the YZ plane. However, even if the input or upstream beam content contains only charged particles moving parallel or nearly parallel to the YZ plane (when these ions begin to traverse the magnetic field generated by the C-yoke coil assembly), the magnetic field The Y-axis component substantially deflects the charged particles in the (positive or negative) X-axis direction.

It should be noted that a component in the X-axis direction of an ion motion in a region having a Z-axis direction component of the magnetic field will cause a skew in the Y-axis direction. Therefore, if, for the sake of example, the ions in the motion are deflected by 30 in the X-axis direction, the component of the ion velocity in this X-axis direction is half of its total velocity.

The amount of X-axis skew is almost independent of the Y-axis coordinate of the plasma, but only a slight correlation is observed. In all cases, the magnitude of the Z-axis component of the magnetic field is related to the Y-axis coordinate, but this change can be changed to some extent by changing the spacing of the bars; and the shape of a bar allows it to be moved to adjust This spacing allows the other bars that are not moved to remain in their most suitable position.

2. The net skew in the X-axis direction is zero; however, the physical offset in the X-axis direction is twice the offset from the first pole and depends on the coil current direction. The net skew in the Y-axis direction is proportional to the square of the current in the coils; therefore, the poles of the currents in the coils Nothing about sex.

As shown in the figure, the net deflection in the Y-axis direction and the amount of motion in the X-axis direction obtained in the end space region 113 are proportional to the Z-axis component of the magnetic field in the intermediate spatial region 112. Since each of these is proportional to the current in the magnet, the total skewing effect in the Y-axis direction is proportional to the square of the current in the coils. The role of the end space region 115 is to accurately reverse the deflection effect of the other end space region 113.

The square of any real number is always positive. Therefore, if the skew in the Y-axis direction is proportional to the square of the current, the skew in the Y-axis direction is always in the same direction regardless of whether the current is in the positive or negative direction within the coils.

In summary: both the X-axis skew and the X-axis offset effect are proportional to the current in the electromagnetic winding coil. If the practitioner reverses the current, the action and event will also reverse the offset. However, the skew in the Y-axis direction will always be skewed away from the pole of the component and will always be proportional to the square of the current.

If the practitioner continues to increase the current, the result is that the ions are swung and then exit the inlet of the yoke coil assembly.

3. The amount of Y-axis skew will vary substantially linearly with the Y-axis coordinate of the ion. Linear variations produce a focus with little or no aberrations; and by carefully shaping the shape and position of the gap distance between individual bars, there may be some optimization.

This Y-axis skew parameter is extremely important in achieving high resolution because the resolution is due to the dispersion (see above) and beam width. The minimum value (i.e., the ratio of the beam passing through the slits 6a and 6b (see Fig. 6b or 10) is calculated.

4. The maximum resolution that can be obtained is determined by the following considerations:

(a) The dispersion available from the device is calculated for a particular example earlier. For generalization, the dispersion D of the device is D = 2 β L where 2 β is the total deflection in the negative y direction, the unit is degrees, and L is the distance of the point to be determined from the center of the device.

(b) Moreover, the optimum resolution of any device is R = D / t. In this example: R = 2 β L / tt is the thickness scale of the beam at the point where the resolution device is located in the direction of mass dispersion. .

(c) Thus, it is apparent that the resolution is greatest where the beam is focused to a minimum thickness; and if the focus can be moved further away from the center of the device, the spread will be greater. Unfortunately, the constant situation is that the focus becomes larger as you move further away from the device.

Therefore, in order to maximize resolution, we must adjust the focus characteristics of the analyzer device to place the focus at a convenient distance, i.e., a selected position that effectively exceeds the magnetic boundary of the device. Moreover, the focus quality of the beam focus should be as free as possible.

5. A unique feature and feature of the present invention is that it is very strong Focus. Therefore, in the C-yoke coil assembly, when the total bending angle is increased to more than about 16 degrees, the focal length is correspondingly reduced. However, expressions that are still not analytical for this relationship are derived, but at a bend angle of 20 degrees, the conjugate focus is very close to the magnet, causing the line winding to interfere with the ion source and others. The mounting of the associated components, and at larger bend angles, the conjugate focus is completely within the magnetic field regions 113 and 115.

Therefore, it follows that, in some cases, a resolution greater than 35 can be obtained in many embodiments of a C-type yoke assembly; however, at present, a resolution of about 35 is considered for the present invention. Words are a safe and tangible maximum.

The invention is not limited in form and is not limited in scope, but is defined by the scope of the appended claims.

1‧‧‧Bridge section

2‧‧‧Electromagnetic coil

10‧‧‧C type yoke coil assembly

13‧‧‧ surface

15‧‧‧ surface

52a‧‧‧Line length section

52b‧‧‧Line length section

Claims (13)

A mass analyzer apparatus adapted to change at least one characteristic of an contiguous moving ribbon ion beam of an arbitrarily selected fixed width dimension, the mass analyzer apparatus comprising: a C-type yoke coil assembly, It will be arranged adjacent to the path of movement of an adjacent strip of ion beam and thereby uniformly span the width dimension of the side-by-side moving ion beam, the C-yoke coil assembly comprising: a form And a tunnel-shaped yoke whose dimensions are set, the (α) having a C-shaped cross section that surrounds more than 180 degrees, and which surrounds three sides of a tunnel-shaped recess and uniformly extends thereto in a straight line Each end of the two separate ends, (β) has two identifiable solid wall arms as a tunnel side and a solid central bridge, (γ) providing two separate arm face surfaces, Having an included angle ranging from about 150 to 175 degrees, and (δ) is made of at least one magnetic metal material; and at least one wound coil disposed on the tunnel yoke, each of which is disposed The wound coil (i) is a runway type long An obround loop that is wound from a multi-turn conductor and includes parallel linear length sections of two conductor windings, and two separate curved ends, wherein each linear length section has a length greater than the movement The width dimension of the strip beam, and each curved end is bent 180 degrees and is connected to the straight length sections, (ii) extending around and surrounding the yoke, (iii) being arranged such that one of the two linear length sections is flat within the tunnel space of the yoke, and the other linear length section is flat on the yoke Outside, (iv) can generate an on-demand magnetic field that is emitted at right angles to the surface of the yoke, whereby a plurality of spatially oriented spatial regions are thereby generated and arranged in a continuous series. The volume, magnetic field strength, and directional effects of the spatial regions in which the plurality of magnetic fields are oriented are generally sufficient to achieve substantial changes in the adjacent moving ion beam. A mass analyzer apparatus adapted to change a trajectory of an contiguous moving ribbon ion beam of an arbitrarily selected width, the mass analyzer apparatus comprising: a separate C-yoke coil assembly that will Arranged to be adjacent to a moving path of a strip of ion beam and thereby span the width dimension of the side-by-side moving ion beam, the C-yoke coil assembly comprising: a tunnel of a form and scale set a yoke having (α) having a C-shaped cross section that is greater than 180 degrees and that surrounds three sides of a tunnel-shaped recess and that extends uniformly in a straight line to its two separate ends At each end, (β) has two identifiable solid wall arms as a side of the tunnel and a solid central bridge, (γ) providing two separate arm face surfaces with a range of about 150 An angle of between 170 degrees, and (δ) is made of at least one magnetic metal material; And at least one wound coil disposed on the tunnel yoke, wherein each of the disposed wound coils (i) is a racetrack type obround loop wound by a plurality of turns of electrical conductors And a parallel linear length section comprising two conductor windings and two separate curved ends, wherein each linear length section has a length greater than a width dimension of the moving strip beam, and each curved end is curved 180 degrees and engaged with the linear length segments, (ii) extending around and surrounding the yoke, (iii) being arranged such that one of the two linear length segments is flat within the tunnel space of the yoke, And another straight length section is flat on the outside of the yoke, (iv) can generate an on-demand magnetic field, which is emitted from the surface of the yoke at right angles, and the spatial regions in which the plurality of magnetic fields are oriented Thereby generated and arranged in a continuous series, the volume, magnetic field strength, and directional effects of the spatial regions in which the plurality of magnetic fields are oriented are generally sufficient to achieve substantial changes in the adjacent moving ion beam. A mass analyzer apparatus adapted to change at least one characteristic of an adjacent moving ribbon ion beam of an arbitrarily selected width, the mass analyzer apparatus comprising: a separate C-yoke permanent magnet assembly Which will be placed contiguously above the path of movement of the strip-shaped ion beam or at a position immediately below the path of movement and thereby span the width dimension of the side-by-side moving ion beam, the C-shaped yoke The permanent magnet assembly contains: A tunnel-shaped yoke having a shape and a dimension, the (α) having a C-shaped cross section that surrounds more than 180 degrees, and which surrounds three sides of a tunnel-shaped recess and uniformly extends in a straight line To each of its two separate ends, (β) has two identifiable solid wall arms as a tunnel side and a solid central bridge, (γ) providing two separate arm faces Having an included angle ranging from about 150 to 175 degrees, and (δ) is made of at least one magnetic metal material; and a permanent magnet constituting at least a portion of the central bridging section of the tunnel yoke, wherein The permanent magnet (i) is a shaped body made of at least one permanent magnet material, (ii) extends over the entire length of the yoke from one end to the other end, (iii) optionally (on- Reducing a magnetic field that extends angularly, a spatial region in which a plurality of magnetic fields are directed thereby generated and arranged in a continuous series, the volume, magnetic field strength, and directional effects of the spatial regions in which the plurality of magnetic fields are oriented Overall sufficient to achieve an adjacency The substantial change in the trajectory of the moving ion beam. The mass analyzer device of claim 1 or 2, further comprising a current source that is selectively in communication with the coil wound around the C-yoke coil assembly. A mass analyzer as described in claim 1, 2 or 3 The apparatus further includes at least two shaped ferromagnetic bars disposed on opposite sides of the adjacent moving ion beam. An operating system adapted to alter at least one identifiable feature of an adjacent moving strip of ion beam, the operating system comprising: a moving strip beam comprising at least one desired ion species, wherein The size dimension of the ion beam may be arbitrarily fixed at a size of less than 100 mm to more than 3000 mm and the thickness dimension of the ion beam is fixed at a size of less than 50 mm; a juxtaposed mass analyzer device comprising a separate C-yoke coil assembly that is disposed adjacent to a path of movement of a ribbon ion beam and thereby spans a width dimension of the moving ion beam, the C-yoke coil assembly comprising: a tunnel-shaped yoke having a shape and a dimension set, wherein (α) has a C-shaped cross section that surrounds more than 180 degrees, and it surrounds three sides of a tunnel-shaped recess, and extends uniformly to the straight line to At each end of its two separate ends, (β) has two identifiable solid wall arms as a tunnel side and a solid central bridge, (γ) providing two separate arm face surfaces, It has a fan An angle between about 150 and 175 degrees, and (δ) is made of at least one magnetic metal material; and at least one wound coil is disposed on the tunnel yoke, wherein each of the wounds is disposed Coil (i) is a runway-type obround loop that is wound by a multi-turn conductor and includes parallel linear length sections of two conductor windings and two separate curved ends, each of which has a straight length The length of the segment is greater than the width dimension of the moving ribbon beam, and each curved end is bent 180 degrees and engages the linear length segments, (ii) extends around and surrounds the yoke, (iii) is Arranging such that one of the two linear length sections is flat within the tunnel space of the yoke, and the other of the linear length sections is flat outside the yoke, (iv) generating an on-demand A magnetic field that is emitted at right angles to the surface of the yoke, a spatial region in which a plurality of magnetic fields are oriented is thereby generated and arranged in a continuous series, the plurality of magnetic fields being oriented in a spatial region The volume, magnetic field strength, and directional effects are generally sufficient to achieve substantial changes in the adjacent moving ion beam; and a current source that is wrapped around the tunnel yoke within the C-yoke coil assembly The wound coils are selectively electrically connected. An operating system adapted to alter at least one identifiable feature of an adjacent moving strip of ion beam, the operating system comprising: a side-by-side moving strip beam comprising at least one desired ion a type in which the size of the width dimension of the ion beam can be arbitrarily fixed at a size of less than 100 mm to more than 3000 mm and the thickness dimension of the ion beam is fixed at a size of less than 50 mm; a mass analyzer device Includes a separate C-type yoke coil assembly, It will be arranged to abut the path of movement of a strip of ion beam and thereby span the width dimension of the adjacent moving ion beam, the C-yoke coil assembly comprising: a form and a scale set a tunnel-shaped yoke having (α) a C-shaped cross section that surrounds more than 180 degrees and that surrounds three sides of a tunnel-shaped recess and that extends uniformly in a straight line to its two separate ends Each end of the portion, (β) has two identifiable solid wall arm members as a tunnel side and a solid central bridge member, (γ) providing two separate arm face surfaces having a range of approximately An angle between 150 and 175 degrees, and (δ) is made of at least one magnetic metal material; and a permanent magnet constituting at least a portion of the central bridging section of the tunnel yoke, wherein the permanent magnet (i) is a shaped body made of at least one permanent magnet material, (ii) extending over the entire length of the yoke from one end to the other end, (iii) optionally extending on a straight-forward basis. a magnetic field in which a plurality of spatial regions are oriented and thereby Are arranged in series continuous manner, the volume of the space region a plurality of such magnetic field is oriented, sufficient to achieve substantial change for the mobile ions in the beam line adjacent the overall magnetic field strength, direction and effect. The system of claim 6 or 7, wherein the A system is used to separate at least one desired ion species from at least one unwanted ion species within the adjacent moving ion beam. The system of claim 6 or 7, wherein the system is used for ballistic deflection of the adjacent moving ion beam. The system of claim 9, wherein the system is configured to bend the width of the adjacent moving ion beam initially in the X-axis direction by an angle of +α, and then to the adjacent The width of the moving ion beam is then bent at an angle of -α to restore the original direction of movement. The system of claim 9, wherein the system is adapted to vary the adjacent moving ion beam from its original ballistic deflection by a net angle greater than about 4 degrees and no greater than about 30 degrees. The system of claim 6 or 7, wherein the system is used for focusing of the adjacent moving ion beam in the Y-Z plane. The system of claim 12, wherein the adjacent moving ion beam becomes focused in the Y-axis direction and has no focusing effect in the X-axis direction.