Patent Publication Number: US-9852882-B2

Title: Annular cooling fluid passage for magnets

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This is a continuation of pending U.S. non-provisional patent application Ser. No. 13/966,611, filed Aug. 14, 2013, claiming priority to U.S. provisional patent application Ser. No. 61/835,089, filed Jun. 14, 2013, the entire contents of the applications incorporated by reference herein. 
    
    
     FIELD OF THE DISCLOSURE 
     Embodiments of the present disclosure generally relate to the field of substrate processing, and more particularly to the cooling of magnets used in conjunction with substrate processing for manufacturing semiconductor devices. 
     BACKGROUND OF THE DISCLOSURE 
     Ions are often used during manufacturing of semiconductor devices. For example, ions may be implanted into a substrate to dope the substrate with various impurities. Ions may be deposited onto a substrate to build up features on the substrate. Ions may also be used to etch away material during the manufacturing process. In general, ions are emitted from an ion source chamber. Magnets are often used to filter the ions and also shape the ions into an ion beam having intended characteristics and direct the ion beam at the substrate. Some of these magnets are formed by wrapping conductive wire around a metal core. Current is then passed through the conductive wire to create a magnetic field. During operation, the magnets often need cooling in order to operate at the power levels necessary to create magnetic fields having intended characteristics. As such, a cooling passage is formed in the metal core for passing cooling fluid during operation. One deficiency in some current designs stems from a cooling passage used at the centerline of the core. As such, heat generated in the windings is be conducted through the thickness of the core in order to reach the cooling fluid. The removal of a relatively large amount of material in order to form a cooling passage of requisite size, as will be appreciated, reduces the amount of material in the metal core and undesirably reduces the strength and effectiveness of the magnetic field created by the magnet. Thus, there is a need for an improved cooling arrangement for magnets used in substrate processing operations. 
     SUMMARY 
     This Summary is provided to introduce a selection of concepts in a simplified form as further described below in the Detailed Description. This Summary is not intended to identify key features or essential features of the claimed subject matter, and is not intended as an aid in determining the scope of the claimed subject matter. 
     In general, various embodiments of the present disclosure provide a magnet comprising a metal core having a cavity therein, one or more conductive wire wraps disposed around the metal core, and an annular core element configured to be inserted into the cavity, wherein an annular coolant fluid passage is formed between the cavity and the annular core element. Furthermore, the annular core element may have a first diameter and a middle section having a second diameter, the second diameter being less than the first diameter. 
     As an alternative example, some embodiments disclose a magnet for use with an ion implant apparatus comprising an ion beam coupler having an aperture disposed there through, a first magnet disposed adjacent to the ion beam coupler, and a second magnet disposed adjacent to the ion beam coupler and the first magnet. The first and second magnets can each include a metal core having a cavity therein, one or more conductive wire wraps disposed around the metal core, and an annular core element configured to be inserted into the cavity. An annular coolant fluid passage may be formed between the cavity and the annular core element. Furthermore, the annular core element may have a first diameter and a middle section having a second diameter, where the second diameter is less than the first diameter. 
     Another example embodiment discloses an apparatus comprising an ion source configured to emit an ion beam, and a magnet positioned downstream of the ion source in a direction of travel of the ion beam, the magnet configured to shape the ion beam. The magnet may have an annular coolant fluid passage defined therein. A coolant fluid reservoir containing a coolant fluid may be connected to the annular coolant fluid passage. A coolant fluid pump may be connected to the coolant fluid reservoir, and may be configured to pump the coolant fluid through the annular coolant fluid passage. The magnet may include a first magnet disposed adjacent to an ion beam coupler and a second magnet disposed adjacent to the ion beam coupler and the first magnet. The first and second magnets may each include a metal core having a cavity therein, one or more conductive wire wraps disposed around the metal core, and an annular core element configured to be inserted into the cavity. An annular coolant fluid passage may be formed between the cavity and the annular core element. Furthermore, the annular core element may have a first diameter and a middle section having a second diameter, where the second diameter is less than the first diameter. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       By way of example, various embodiments of the disclosed device will now be described, with reference to the accompanying drawings, wherein: 
         FIG. 1  is a block diagram of an exemplary ion implant apparatus; 
         FIGS. 2A-2B  are block diagrams of an exemplary quadrupole magnet; 
         FIG. 3  is a block diagram of an exemplary coolant fluid flow path through the quadrupole magnet of  FIGS. 2A-2B ; 
         FIG. 4  is a block diagram of another exemplary coolant fluid flow path through the quadrupole magnet of  FIGS. 2A-2B ; and 
         FIGS. 5A-5I  are block diagrams of an annular coolant fluid passage through a magnet, all arranged in accordance with embodiments of the present disclosure. 
     
    
    
     DETAILED DESCRIPTION 
     The disclosed magnets and methods of cooling magnets are described in connection with a general ion implant apparatus and a quadrupole magnet. As will be appreciated, various embodiments of the present disclosure may be applied to other magnets of an ion apparatus. For example, various embodiments of the present disclosure may be used in an ion deposition apparatus, such as, a plasma-ion deposition apparatus. As another example, various embodiments of the present disclosure may be used in an ion etching apparatus. Furthermore, as described above, various embodiments of the present disclosure provide an annular cooling passage through a metal core of a magnet. Illustrative examples of annular coolant fluid passages are described in greater detail below, particularly with reference to  FIGS. 5A-5H . Overall systems and illustrative configurations of the magnets having such annular cooling passages are described first with reference to  FIG. 1  and  FIGS. 2A-2B . Additionally, illustrative examples of coolant fluid flow paths through an example magnet are described with reference to  FIGS. 3-4 . 
       FIG. 1  illustrates a block diagram of an example ion implant apparatus  100 , arranged in accordance with at least some embodiments of the present disclosure for generate a ribbon beam. Other ion implant apparatus may generate a scanned spot beam having diverging trajectories deflected to be approximately parallel before striking a workpiece. In general, some or all of the components of the ion implant apparatus  100  may be enclosed in a process chamber  102 . As depicted, the ion implant apparatus  100  includes an ion source  104  configured to generate ions of a particular species. The ion source  104  may include a heated filament for ionizing a feed gas introduced into the process chamber  102  to form charged ions and electrons (plasma). The heating element may be, for example, a Bernas source filament, an indirectly heated cathode (IHC) assembly or other thermal electron source. Different feed gases may be supplied to the ion source chamber to obtain ion beams having particular dopant characteristics. For example, the introduction of H 2 , BF 3  and AsH 3  at relatively high chamber temperatures are broken down into mono-atoms having high implant energies. High implant energies are usually associated with values greater than 20 keV. For low-energy ion implantation, heavier charged molecules such as decaborane, carborane, etc., may be introduced into the source chamber at a lower chamber temperature, thus preserving the molecular structure of the ionized molecules having lower implant energies. Low implant energies may have values below 20 keV. 
     The generated ions are extracted from the source through a series of electrodes  106  and formed into an ion beam  108  passing through a first magnet  110 . In some examples, the first magnet  110  may be a mass analyzer magnet configured with a particular magnetic field so just the ions with an intended mass-to-charge ratio are able to travel through the analyzer for maximum transmission through a quadrupole magnet  112 . The quadrupole magnet  112  may comprise a metal core wound with conductive wire configured to shape the ion beam  108  to have specific dimensions. 
     Upon exiting the quadrupole magnet  112 , the ion beam  108  may pass through a mass resolving slit and onto a deceleration stage  114 . The deceleration stage  114  may comprise multiple electrodes  116  with defined apertures for allowing ion beams having specific characteristics to pass there through. By applying different combinations of voltage potentials to the electrodes  116 , the deceleration stage  114  manipulates the ion energies in the ion beam  108 . 
     A corrector magnet  118  may be disposed downstream of the deceleration stage  114 . The corrector magnet  118  may be configured to deflect ion beamlets in accordance with the strength and direction of the applied magnetic field to provide a ribbon beam targeted toward a substrate  120  positioned on a platen  122  (i.e., support structure). As will be appreciated, the corrector magnet  118  “shapes” the ion beam  108  after the ion beam  108  leaves the deceleration stage  114  into the correct form for deposition onto the substrate  120 . In addition, the corrector magnet  118  may be configured to filter out any ions from the ion beam  108  neutralized when traveling through the beam line. 
     During operation, the magnets and other components of the ion implant apparatus may need cooling. For example, the ion source  104 , the first magnet  110 , the quadrupole magnet  112 , the corrector magnet  118 , or the platen  122  may need cooling. As a particular example, the quadrupole magnet  112  may in some instances be configured to draw over 50 Amps of current. The amount of current flowing through the conductive wire of the quadrupole magnet may therefore cause an excess amount of heat to be generated. As a result, coolant fluid may be passed through the quadrupole magnet  112  in order to draw the generated heat away from the quadrupole magnet  112 . 
     As such, the ion implant apparatus  100  may include a coolant reservoir  124  configured to hold coolant fluid  126  and a corresponding coolant path  128 . A coolant pump  130  for circulating coolant fluid  126  through the coolant path  128  may also be included in the ion implant apparatus  100 . The coolant pump  130  can be a centrifugal pump, a positive displacement pump, or any other type of pump appropriate to provide an intended flow rate and coolant pressure for circulating coolant fluid  126  through the coolant path  128 . As depicted, the coolant path  128  passes through various components of the ion implant apparatus  100 . Accordingly, during operation, coolant fluid  126  may be pumped through the components by the coolant pump  130  in order to cool the components. In some examples, the coolant fluid  126  may be water, water with glycol, galdin, flourinert, or another fluid having desirable heat absorption and dielectric properties. 
     As the coolant path  128  passes through various component of the ion implant apparatus  100  (e.g., the quadrupole magnet  112 ,) a coolant passage may exist in the various components. An annular coolant fluid passage (described in greater detail below) may exist in at least one of the components. Accordingly, as coolant is passed through the component during operation heat from the components may be transferred to the coolant and carried away from the components along the coolant path  128 . In some examples, a heat exchanger and/or chiller (not shown) may also be provided to cool the coolant fluid  126 . For example, the coolant fluid reservoir may be a combined reservoir and heat exchanger. The illustrated arrangement is merely exemplary, and the particular coolant path  128 , arrangement of the coolant reservoir  124 , and arrangement of the coolant pump  130  can be modified from the illustrated approach as intended for a specific application. Further, multiple coolant paths, coolant pumps, and/or coolant reservoirs can also be provided, as intended. For example, although the illustrated system shows a closed loop recirculating cooling system, a “once-through” system could also be used. 
       FIG. 2A  illustrates an exemplary quadrupole magnet  200 , arranged according to various embodiments of the present disclosure. In some examples, the quadrupole magnet  200  may correspond to the quadrupole magnet  112  shown in  FIG. 1 . As depicted, the quadrupole magnet  200  includes a first magnet  210  and a second magnet  220  disposed around an ion beam coupling  230  having an aperture  232 . In general, during operation, the ion beam  108  passes through the aperture  232  and the magnetic field created by the first magnet  210  and the second magnet  220  shapes the ion beam  108  to have specific properties (e.g., intended height and/or width). 
     The first and second magnets  210 ,  220  include metal cores  211 ,  221 , wrapped by conductive wire, forming conductive wire wraps  212 ,  222 . One will appreciate the number of conductive wire wraps  212 ,  222  are shown for illustrative purposes and are not intended to be limiting. Furthermore, the quadrupole magnet  200  may be configured to have either a quadrupole or a dipole function depending upon the polarity of voltage applied to the conductive wire wraps  212 ,  222 . The geometry of the metal cores  211 ,  221  and positioning of the conductive wire wraps  212 ,  222  may also be adjusted to achieve a magnetic field having an intended shape and strength. 
     The first and second magnets  210 ,  220  are disposed inside a housing  240 . The housing  240  can be configured to hold the first and second magnets  210 ,  220  in an intended position with respect to the ion beam coupling  230  and to enable the quadrupole magnet  200  to be mounted within the ion implant apparatus  100 . 
     The first and second magnets  210 ,  220  can further include coolant fluid couplings  213 ,  223 ,  214 ,  224 . In general, the coolant fluid couplings  213 ,  223 ,  214 ,  224  are configured to facilitate passage of coolant fluid  126  through the metal cores  211 ,  221 . As previously noted, during operation of the quadrupole magnet  220 , as current is passed through the conductive wire wraps  212 ,  222 , the conductive wire wraps will heat up. If the heat is not dissipated (e.g., by passage of coolant fluid through the metal cores  211 ,  221 ) then the quadrupole magnet  200  may shut down, melt, or otherwise malfunction. Coolant fluid couplings  213 ,  223 ,  214 ,  224  are shown for directing coolant fluid  126  through the metal cores  211 ,  221  along respective coolant flow paths  215 ,  225 . As will be described in greater detail below, the coolant flow paths  215 ,  225  illustrated in these figures are representational, and may correspond to annular coolant fluid passages within the metal cores  211 ,  221 , as will be described in greater detail in relation to  FIGS. 5A-5I . 
       FIG. 2B  is a top view of the quadrupole magnet  200  shown in  FIG. 2A . As depicted, the first and second magnets  210 ,  220  are shown disposed around the ion beam coupling  230 . The housing  240  is shown disposed around the first and second magnets  210 ,  220 . Furthermore, coolant fluid couplings  213 ,  223  are also shown, associated with the first and second magnets  210 ,  220 , respectively. 
     With some examples, the metal cores  211 ,  221  may be formed from a steel alloy, such as, low carbon steel, or other metal having properties suitable for the core of a magnet. The conductive wire wraps  212 ,  222  may be formed from a conductive wire, such as, copper. Furthermore, with some embodiments, the metal cores  211 ,  221  and the conductive wire wraps  212 ,  222  may be encased in an epoxy or other suitable dielectric material. 
     In some examples, the coolant flow paths  215 ,  225  may be configured in a parallel manner. For example,  FIG. 3  illustrates the quadrupole magnet  200  having the coolant flow paths  215 ,  225  arranged in a parallel manner. As depicted, the quadrupole magnet  200  includes an inlet tee  302  connected with the coolant fluid couplings  213 ,  223  and an outlet tee connecting the coolant fluid couplings  214 ,  224 . Coolant fluid  126  may enter through inlet tee  302 , where the coolant fluid is directed along the coolant flow paths  215 ,  225  simultaneously. Coolant fluid  126  flows through the metal cores  211 ,  221  and exits through outlet tee  304 . As one will appreciate, such an arrangement of coolant flow ensures the first and second magnets  210 ,  220  are subjected to coolant fluid  126  at approximately the same temperature, thus resulting is relatively even cooling of the first and second magnets. 
     In some examples, the coolant flow paths  215 ,  225  may be configured in a series manner. For example,  FIG. 4  illustrates the quadrupole magnet  200 . As depicted, the quadrupole magnet  200  includes a return pipe  402  connecting the coolant fluid couplings  214 ,  224 . Accordingly, during operation, coolant fluid  126  may be passed through metal cores  211 ,  221  along coolant flow paths  215 ,  225  in a series manner. For example, coolant fluid  126  may enter metal core  211  of the first magnet  210  via coolant fluid coupling  213 , may pass through the metal core  211  along the coolant passage  215 , and may exit the metal core  211  via coolant fluid coupling  214 . Coolant fluid may then pass through the return pipe  402  to coolant fluid coupling  224 , may enter the metal core  221  of the second magnet  220  at coolant fluid coupling  224 , may pass through the metal core  221  along coolant flow path  225 , and may exit the metal core  221  through coolant fluid coupling  223 . This arrangement may be slightly less complex to implement as compared to the parallel flow arrangement described in relation to  FIG. 3 . With the arrangement of  FIG. 4 , the coolant fluid  126  may have a slightly higher temperature when the coolant fluid  126  passes through the second metal core  221  as compared to when the coolant fluid  126  passes through the first metal core  211  (owing to the heat transferred away from the first metal core). Thus, overall cooling of the second metal core  221  may be slightly less than the overall cooling of the first metal core  211 . This, of course, could be compensated for by providing flow channels in the second metal core  221  being larger, or having different geometry, as compared to those of the first metal core  211 . 
       FIG. 5A  is an exploded view of a magnet  500  (minus the conductive metal wraps, for clarity) arranged according to various embodiments of the present disclosure. As depicted, the magnet  500  may correspond to either the first magnet  210  and/or the second magnet  220  of the quadrupole magnet  200  described in relation to the previous figures. The magnet  500  includes a metal core  502 , having conductive wire wrapped around the metal core  502 , forming conductive wire wraps  504 . The metal core  502  has material removed from it, forming a cavity  506  running from a top of the metal core to a bottom of the metal core. The magnet  500  also includes an annular core element  508 , configured to fit within the cavity  506 . Upper and lower o-rings  510 ,  512  as well as end caps  514  are also shown (just one end cap can be seen in this view). As depicted, the upper and lower o-rings  510 ,  512  may fit within corresponding circumferential grooves in the annular core element  508  that may be inserted into the cavity  506  and secured with an end caps  514  (see  FIG. 5H ). 
       FIG. 5B  is a top view of the metal core  502  alone, showing the cavity  506 . The cavity  506  may have a cavity diameter  507  sized to receive the annular core element  508 . As will be appreciated, the top view of the metal core  502  shown in  FIG. 5B  may also correspond to the bottom view (not shown) of the metal core  502 .  FIG. 5C  illustrates a cross-section view of the metal core  502 . The cross-section view of the metal core  502  is shown with the cut along the length of the cavity  506 . As can be seen from these figures, the cavity  506  extends along the entire length of the metal core  502 . 
       FIG. 5D  illustrates a top view of the annular core element  508 . As will be appreciated, the top view of the annular core element  508  shown in  FIG. 5D  may also correspond to the bottom view (not shown) of the annular core element  508 . As can be seen, an external coolant fluid opening  516  is centrally disposed in the top end of the annular core element  508  for admitting coolant fluid  126  into the annular core element. A similar opening is provided in the bottom end of annular core element  508  (used as an outlet for coolant fluid  126 ) as can be seen in  FIG. 5H .  FIG. 5E  illustrates a side view of the annular core element  508 . The annular core element  508  is shown having a first diameter  520  associated with a top end of the annular core element. As depicted, the annular core element  508  also includes upper and lower circumferential o-ring receiving recesses  522 ,  524  as well as internal coolant fluid openings  526 . The internal coolant fluid openings  526  are coupled to the external coolant fluid openings  516  positioned at the top and bottom of the annular core element  598 , and can be employed to direct coolant fluid  126  to and from an annulus formed between the metal core  502  and the annular core element  508 , as will be described in greater detail later. The annular core element  508  may includes a middle section  528  having a second diameter  530  smaller than the first diameter  520 . The first diameter  520  may be slightly smaller than the cavity diameter  507  of the metal core  502  (see  FIG. 5I ) so the annular core element  508  can be slid into engagement with the cavity  506  of the metal core. As will be appreciated, the difference in diameters between the middle section  528  of the annular core element  508  and the metal core  502  creates an annular coolant fluid passage  538  (best seen in  FIG. 5H ) for effectively cooling the metal core during operation. 
       FIG. 5F  is a cross-section view of the annular core element  508 . The cut away view depicted in  FIG. 5F  is shown with the cut along the length of the annular core element and parallel to the internal coolant fluid holes  526 . As can be seen, the annular core element  508  includes internal coolant passages  532  formed between the external coolant fluid openings  516  and the internal coolant fluid openings  526 .  FIG. 5G  illustrates another cross-section view of the annular core element  508 . The cross-section view depicted in  FIG. 5G  is shown rotated 90-degrees with respect to the view depicted in  FIG. 5F . 
       FIG. 5H  is a cross-section view of the metal core  502  with the annular core element  508  disposed within the cavity  506 . As can be seen, the annular core element  508  is secured to the metal core  502  with end caps  514 , and is fluidically sealed to the metal core via upper and lower o-rings  510 ,  512  disposed in the upper and lower circumferential o-ring receiving recesses  522 ,  524 . External coolant fluid openings  516  and internal coolant fluid openings  526  are also shown. In some examples, the external coolant fluid openings  516  may be configured (e.g., threaded, tapered, or the like) to receive one of the previously described coolant fluid couplings  213 ,  223 ,  214 , or  224 . As such, the annular core element  508  may be fluidly connected to coolant fluid lines (e.g., the coolant fluid path  128  shown in  FIG. 1 ).  FIG. 5I  illustrates a top view of the metal core  502  having the annular core  508  disposed thereon and secured with one of the end caps  514  having one of the external coolant fluid opening  516  exposed. 
     An exemplary coolant fluid flow path (represented by dotted arrow  538 ) through the annular coolant fluid passage  536  is shown. In some examples, the coolant fluid flow path  538  may generally correspond to either of coolant paths  215  or  225  shown in  FIGS. 2A-2B  and  FIGS. 3-4 . During operation, coolant fluid  126  may be pumped into one of the external coolant fluid openings  516  (at the top of the magnet, in the illustrated embodiment). The coolant fluid  126  may then pass through the corresponding internal coolant passages  532 , out the corresponding internal coolant openings  526 , and into the annular coolant fluid passage  536 . As can be seen, the annular coolant fluid passage  536  is disposed adjacent the region of the metal core  502  including the conductive wire wraps (not shown in this view, for clarity), and thus most of the heat transfer from the magnet  500  to the coolant fluid  126  occurs as the coolant fluid navigates the annular coolant fluid passage  536 . Heated coolant fluid  126  may then pass into the internal coolant openings  526  in the lower portion of the annular core element  508 , through the corresponding internal coolant passages  532  and out the external coolant fluid opening  516  (at the bottom of the magnet in the illustrated embodiment). One will appreciate coolant fluid flow needn&#39;t be from top to bottom, and instead could be arranged to flow from the bottom of the magnet to the top. 
     In some embodiments, effective cooling of the magnet  500  is accomplished when the coolant fluid  126  is perturbed into the turbulent flow regime within the annular coolant fluid passage  536 . As will be appreciated, this coolant fluid passage  536  allows the coolant fluid  126  to be close to the heat source (i.e., the conductive wire wraps) and still have the necessary core steel to maintain intended magnetic field performance. This is an advantage over standard cooling arrangements having one cylindrical passage through the metal core on the center line, limiting the overall heat transfer surface and places the coolant fluid a large distance from the heat source (i.e., the conductive wire wraps), and limiting cooling capacity by the conduction of the heat through the core. 
     In some examples, the first diameter  520  and the second diameter  530  may be selected so a flow rate of between 0.25 gallons per minute and 3 gallons per minute are achieved when coolant fluid is  126  is passed through the annular coolant fluid passage  536 . In some examples, the first diameter  520  and the second diameter  530  may be selected so coolant fluid  126 , having a temperature of between 15 and 30 degrees Celsius, enters the coolant fluid passage  536 , absorbs heat from the metal core  502  and the annular core  508 , and then exists the coolant fluid passage  536  with an elevated temperature of between 26 and 42 degrees Celsius. 
     As will be appreciated the annular coolant fluid passage  536  may be circular in shape. More specifically, the annular coolant fluid passage  536  may correspond to the space formed between the middle section  528  of the annular core element  508  and the cavity diameter  507  of the metal core  502 , as described in relation to  FIG. 5B . 
     One will appreciate, the dimensions of the annular core element  508 , and particularly the first diameter  520  and the second diameter  530 , may be selected so the coolant fluid flow rate through the annular coolant fluid passage  536 , and the heat transfer parameters, allow for an intended level of heat dissipation from the metal core  502 . As an illustrative example, the first diameter  520  may be 1.25 inches while the second diameter  530  may be 1.20 inches. Such an arrangement would result in an annular coolant fluid passage  536  having a radial width (i.e., distance between the outer surface of the annular core element  508  and inner surface of the metal core  502 ) of approximately 0.025 inches. As another illustrative example, the first diameter  520  may be 1.25 inches while the second diameter  530  may be 1.00 inches. Such an arrangement would result in an annular coolant fluid passage  536  having a radial width (i.e., distance between the outer surface of the annular core element  508  and inner surface of the metal core  502 ) of approximately 0.125 inches. With some examples, the ratio of the first diameter  520  to the second diameter  530  may be determined based on balancing the amount of coolant flow through the annular coolant fluid passage  536  and removing as little material from the middle section  528  as possible. For example, the scenario described above where the first diameter  520  is 1.25 inches and the second diameter  530  is 1.20 inches may be preferable over the other scenario as less material is removed from the annular core  508  in the first scenario. 
     In some examples, the metal core  502  and the annular core element  508  may be formed from the same material (e.g., low carbon steel, or the like). Accordingly, the material available to form the magnetic field during operation of the magnet  500  (e.g., the combined material of the metal core  502  and the annular core element  508 ) may be similar to a solid metal core  502  (i.e., metal core not including the cavity  506 ). As such, the characteristics of the magnetic field formed by magnet  500  may be improved over prior devices, while still maintaining an ability to effectively cool the magnet  500 . In some examples, the amount of current passing through the conductive wire wraps  504  may be advantageously increased as compared to prior devices due to the increase in cooling capacity of the disclosed magnet  500 . 
     The present disclosure is not to be limited in scope by the specific embodiments described herein. Indeed, other various embodiments of and modifications to the present disclosure, in addition to those described herein, will be apparent to those of ordinary skill in the art from the foregoing description and accompanying drawings. Thus, such other embodiments and modifications are intended to fall within the scope of the present disclosure. Furthermore, although the present disclosure has been described herein in the context of a particular implementation in a particular environment for a particular purpose, those of ordinary skill in the art will recognize its usefulness is not limited thereto, and the present disclosure may be beneficially implemented in any number of environments for any number of purposes. Accordingly, the claims set forth below may be construed in view of the full breadth and spirit of the present disclosure as described herein.