Magnetic solid state electro-migration device and method

Abstract

The application provides a solid-state electromigration device and method caused by magnetism, which comprises a furnace body, a vacuum system, a heating system and a magnetic field generating device. The furnace body is internally provided with a vacuum cavity. The vacuum system is in communication with the vacuum cavity. The heating system comprises an electrode assembly arranged in the furnace body, which is used for clamping a metal rod and passing direct current into the metal rod. The magnetic field generating device is arranged around the vacuum cavity and is used for generating an annular magnetic field around the metal rod. The annular magnetic field is configured to have a preset included angle with the current direction in the metal rod, so that the annular magnetic field and the electric field generated by the direct current jointly drive the directional migration of impurity atoms in the metal rod. By applying the annular magnetic field with the preset included angle and jointly acting with the direct current field, the migration rate and direction of the impurity atoms are effectively controlled, the purification efficiency is improved, and the purification period is shortened.

Description

Technical Field

[0001] This application belongs to the field of metallurgical technology, specifically relating to a magnetostrictive solid-state electromigration device and method. Background Technology

[0002] Solid-state electromigration involves forming the metal to be purified into a rod. When a direct current is applied to the rod, the free electrons and holes in the metal move directionally as current carriers. Under the combined action of electrostatic force, electron collision friction, and hole friction, impurity atoms migrate directionally along the rod and accumulate at one end. After cutting off the end, the purified high-purity metal is obtained.

[0003] However, existing solid-state electromigration equipment relies solely on a single electric field to drive impurity migration, lacking the ability to regulate the direction of electron movement with an external magnetic field. This limits the migration rate of impurity atoms, resulting in long purification cycles and low efficiency, making it difficult to meet the demand for high-efficiency purification. Summary of the Invention

[0004] Therefore, the technical problem to be solved by this application is to provide a magnetostrictive solid-state electromigration device and method, which can regulate the direction of electron movement and accelerate the directional migration of impurity atoms through the synergistic effect of an external magnetic field and a DC electric field, thereby improving purification efficiency and shortening the purification cycle.

[0005] To address the aforementioned problems, a first aspect of this application provides a magnetostrictive solid-state electromigration device, comprising: a furnace body, a vacuum system, a heating system, and a magnetic field generating device; the furnace body has a vacuum cavity inside, and the vacuum system is connected to the vacuum cavity; the heating system includes an electrode assembly disposed within the furnace body, the electrode assembly clamping a metal rod and supplying it with direct current; the magnetic field generating device is arranged around the vacuum cavity to generate a ring magnetic field surrounding the metal rod; The annular magnetic field is configured to have a preset angle with the direction of the current in the metal rod, so that the annular magnetic field and the electric field generated by the direct current jointly drive the directional migration of impurity atoms in the metal rod.

[0006] Optionally, the vacuum system includes a mechanical pump, a molecular pump, an ion pump, and a titanium sublimation pump, which are connected in series to form a four-stage pump group.

[0007] Optionally, the magnetostrictive solid-state electromigration device further includes a pneumatic baffle valve, which is installed on the vacuum pipeline between the vacuum system and the furnace body; the vacuum chamber is provided with a vacuum measurement interface, which is connected to a vacuum gauge.

[0008] Optionally, the electrode assembly includes an electrode rod, a clamp, and a flexible connection assembly, wherein the flexible connection assembly is disposed between the electrode rod and the clamp; the flexible connection assembly has a stacked structure comprising multiple flexible connecting sheets, and is configured to absorb the displacement through interlayer relative sliding or deformation of the stacked structure when the bar stock is displaced due to thermal expansion or contraction.

[0009] Optionally, the flexible connecting piece is a tantalum sheet, and multiple tantalum sheets are stacked to form the laminated structure; wherein, one end of the laminated structure is fixedly connected to the electrode rod by bolts, and the other end is fixedly connected to the clamp by bolts.

[0010] Optionally, the inner wall of the vacuum chamber is provided with a tungsten shielding layer, which is fixed to the vacuum chamber by a fixing flange seat at the bottom.

[0011] Optionally, the magnetostrictive solid-state electromigration device further includes a control system and a water-cooling system; the control system is electrically connected to the vacuum system, the heating system and the magnetic field generator, and is used to monitor and control the operating status of the vacuum system, the heating power and temperature of the heating system and the operating status of the magnetic field generator, respectively; the furnace body and the electrode rod are both provided with water-cooling jackets, and the water-cooling system is connected to the water-cooling jackets inside the furnace body and the electrode rod, respectively.

[0012] Optionally, the magnetic field generating device includes an electromagnetic coil surrounding the vacuum cavity; wherein the preset included angle is 90°, and the direction of the annular magnetic field generated by the electromagnetic coil is perpendicular to the direction of the current in the metal rod.

[0013] A second aspect of this application provides a magnetostrictive solid-state electromigration method using the magnetostrictive solid-state electromigration apparatus as described above, comprising: The metal bars are vertically clamped onto the electrode assembly inside the furnace; Start the vacuum system to evacuate the vacuum chamber inside the furnace. Direct current is supplied to the metal rod through the electrode assembly to heat the metal rod and maintain it at the solid target purification temperature. At the same time, the magnetic field generator is turned on to form a ring magnetic field in the area where the metal rod is located. By maintaining the temperature and continuously drawing a vacuum, impurity atoms in the metal rod are directionally migrated to one end, thus completing solid-state electromigration purification.

[0014] Optionally, activating the vacuum system to evacuate the vacuum chamber inside the furnace includes: The mechanical pump and molecular pump are turned on in sequence to start evacuating the vacuum until the first vacuum level is reached in the vacuum chamber. Turn on the ion pump and continue evacuating the vacuum until the second vacuum level is reached in the vacuum chamber. Turn on the titanium sublimation pump to evacuate until the vacuum chamber reaches the third vacuum level; The first vacuum degree is 10. -4 Pa, the second vacuum degree is 10 -7 Pa, the third vacuum degree is 10 - 8 Pa.

[0015] Beneficial effects The magnetostrictive solid-state electromigration device and method provided in the embodiments of this application, by setting a magnetic field generating device surrounding a vacuum cavity around the furnace body, and configuring the annular magnetic field to have a preset angle with the current direction inside the metal rod, so that during the electromigration process, the electric field generated by the direct current and the annular magnetic field act together on the impurity atoms inside the metal rod. The annular magnetic field can change the direction of electron movement, and together with the electric field force, drive the impurity atoms to migrate in a directional manner, thereby solving the problem of low purification efficiency caused by relying on a single electric field in existing equipment, significantly improving purification efficiency and shortening the purification cycle. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of the magnetostrictive solid-state electromigration device according to an embodiment of this application; Figure 2 This is a flowchart of a magnetostrictive solid-state electromigration method according to an embodiment of this application.

[0017] The reference numerals in the attached figures are as follows: 1. Furnace body; 11. Tungsten shielding layer; 12. Observation window; 2. Vacuum system; 21. Mechanical pump; 22. Molecular pump; 23. Ion pump; 24. Titanium sublimation pump; 3. Electrode assembly; 4. Magnetic field generating device; 5. Pneumatic baffle valve; 6. Control system; 10. Metal bar stock. Detailed Implementation

[0018] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0020] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0021] The embodiments of this application are described below with reference to the accompanying drawings. It should be understood that the embodiments described herein are for illustration and explanation only and are not intended to limit this application.

[0022] like Figure 1 As shown, according to a first aspect of an embodiment of this application, a magnetostrictive solid-state electromigration device is provided, including a furnace body 1, a vacuum system 2, a heating system, and a magnetic field generating device 4; the furnace body 1 is provided with a vacuum cavity, and the vacuum system 2 is connected to the vacuum cavity; the heating system includes an electrode assembly 3, which is disposed in the furnace body 1, and holds a metal rod 10 and supplies direct current to it; the magnetic field generating device 4 is disposed around the vacuum cavity to generate a ring magnetic field around the metal rod 10; wherein the ring magnetic field is configured to have a preset angle with the current direction in the metal rod 10, so that the ring magnetic field and the electric field generated by the direct current jointly drive the directional migration of impurity atoms in the metal rod 10.

[0023] By setting up a magnetic field generating device 4 surrounding the vacuum cavity, a ring magnetic field is applied to the metal rod 10 during the electromigration process. The ring magnetic field forms a preset angle with the current direction inside the metal rod 10, so that the electric field generated by the direct current and the ring magnetic field act together on the impurity atoms inside the metal rod 10. Under the combined action of electric and magnetic forces, the migration rate and direction of the impurity atoms are effectively controlled, thereby significantly improving the purification efficiency and shortening the purification cycle.

[0024] The magnetic field generating device 4 is installed around the periphery of the vacuum cavity, and the metal rod 10 is placed vertically in the central area of ​​the vacuum cavity. The current flows along the axial direction of the metal rod 10, and the annular magnetic field generated by the magnetic field generating device 4 is distributed around the metal rod 10, so that the direction of the magnetic field lines of the annular magnetic field forms a preset angle with the axial direction of the metal rod 10.

[0025] In one specific embodiment, the magnetic field generating device 4 includes an electromagnetic coil surrounding the vacuum cavity, with a preset included angle of 90°, that is, the direction of the annular magnetic field generated by the electromagnetic coil is perpendicular to the direction of the current in the metal rod 10.

[0026] By setting up an electromagnetic coil surrounding the vacuum cavity, a ring magnetic field is generated around the metal rod 10 after being energized. The direction of the magnetic field lines of the ring magnetic field is perpendicular to the axis of the metal rod 10, that is, it forms a 90° angle with the direction of the current. At this time, the Lorentz force on the electrons in the magnetic field is the greatest, and the deflection effect on the direction of electron motion is the most significant. Thus, the purification process is accelerated by controlling the migration rate and direction of impurity atoms.

[0027] Furthermore, the electromagnetic coil is made of copper coil wound around the outer wall of the vacuum cavity. The metal rod 10 is vertically clamped at the center of the vacuum cavity. The current flows vertically along the axis of the metal rod 10. The magnetic field lines of the annular magnetic field generated by the electromagnetic coil after being energized are distributed around the circumference of the vacuum cavity and are perpendicular to the axis of the metal rod 10.

[0028] Vacuum system 2 includes mechanical pump 21, molecular pump 22, ion pump 23 and titanium sublimation pump 24, which are connected in series to form a four-stage pump group.

[0029] A four-stage pump system is used to evacuate the vacuum in stages: mechanical pump 21 performs rough evacuation, molecular pump 22 performs fine evacuation, and ion pump 23 and titanium sublimation pump 24 achieve ultra-high vacuum evacuation, ensuring that the cold-state ultimate vacuum level in the vacuum chamber is not less than 10. -8 Pa, hot ultimate vacuum degree not less than 10 -7 The ultra-high vacuum environment of Pa avoids the oxidation and contamination of active metals at high temperatures, providing environmental conditions for solid-state electromigration purification.

[0030] In one embodiment, the magnetostrictive solid-state electromigration device further includes a pneumatic baffle valve 5, which is disposed on the vacuum pipeline between the vacuum system 2 and the furnace body 1; a vacuum measurement interface is provided on the vacuum chamber, and a vacuum gauge is connected to the vacuum measurement interface.

[0031] The pneumatic baffle valve 5 controls the opening and closing of each section of the vacuum pipeline, realizing the vacuum interlock control between each pump group. The vacuum gauge monitors the vacuum level in the vacuum chamber in real time and feeds the data back to the control system 6, realizing the fully automatic operation of the vacuum system.

[0032] The pneumatic baffle valve 5 includes a first pneumatic baffle valve installed on the vacuum pipeline between the molecular pump 22 and the ion pump 23, and a second pneumatic baffle valve installed on the vacuum pipeline between the ion pump 23 and the titanium sublimation pump 24. The vacuum measurement interface is located on the side wall of the vacuum chamber, and the vacuum gauge is fixedly installed on the vacuum measurement interface. The data of the vacuum gauge is interlocked with each pneumatic baffle valve to achieve interlocked control.

[0033] The electrode assembly 3 includes an electrode rod, a clamp, and a flexible connection assembly. The flexible connection assembly is disposed between the electrode rod and the clamp. The flexible connection assembly has a stacked structure comprising multiple flexible connecting sheets and is configured to absorb displacement by interlayer relative slippage or deformation of the stacked structure when the metal rod 10 is displaced due to thermal expansion or contraction.

[0034] Through the layered structure of the flexible connecting components, when the metal rod 10 undergoes axial or radial displacement due to thermal expansion or contraction during long-term high-temperature energization, the multiple flexible connecting sheets can undergo slight relative slippage or elastic deformation, adaptively absorbing displacement and stress, avoiding sample damage or clamping failure due to thermal deformation, and ensuring continuous and stable clamping of the solid metal rod 10 at high temperatures of 2000℃.

[0035] The electrode rod is vertically arranged in the vacuum chamber. The electrode rod is a water-cooled oxygen-free copper electrode rod with a water-cooled jacket inside. The chuck is a high-temperature resistant chuck located below the electrode rod. The flexible connection component is arranged between the lower end of the electrode rod and the upper end of the chuck. The metal rod 10 is clamped in the chuck. The electrode rod, the flexible connection component, the chuck, and the metal rod 10 are connected sequentially from top to bottom in the vertical direction.

[0036] In one specific embodiment, the flexible connecting piece is a tantalum sheet, and multiple tantalum sheets are stacked to form a layered structure; wherein, one end of the layered structure is fixedly connected to the electrode rod by bolts, and the other end is fixedly connected to the clamp by bolts.

[0037] Tantalum possesses characteristics such as high melting point, high temperature resistance, and good chemical stability, and will not release impurities to contaminate the metal rod material under high temperature and ultra-high vacuum environments. The stacked structure of multiple tantalum sheets is fixedly connected to the electrode rod and clamp respectively by bolts, which is reliable and easy to assemble and disassemble. At the same time, the stacked structure provides flexible deformation capability.

[0038] Each tantalum sheet is 0.1 mm thick. Multiple tantalum sheets are stacked sequentially to form a layered structure. The upper end of the layered structure is fixedly connected to the lower end face of the electrode rod by bolts, and the lower end of the layered structure is fixedly connected to the upper end face of the clamp by bolts. Direct current is conducted sequentially through the electrode rod, the layered structure, and the clamp to the metal rod 10.

[0039] In one specific embodiment, a tungsten shielding layer 11 is provided on the inner wall of the vacuum chamber, and the tungsten shielding layer 11 is fixed to the vacuum chamber by a fixed flange seat at the bottom.

[0040] By using the tungsten shielding layer 11 to thermally shield the inner wall of the vacuum chamber, the heat generated by the high-temperature radiation of the metal rod 10 can be blocked from being transferred to the inner wall of the vacuum chamber, preventing the release of impurity elements due to heat and avoiding secondary pollution of the metal rod 10.

[0041] The tungsten shielding layer 11 has a cylindrical structure and is arranged around the metal rod 10. It is located between the metal rod 10 and the inner wall of the vacuum chamber. The bottom of the tungsten shielding layer 11 is fixedly installed at the bottom of the vacuum chamber by a fixed flange seat.

[0042] In one specific embodiment, an observation window 12 is provided on the furnace body 1. The state of the metal bar 10 inside the vacuum chamber can be observed in real time through the observation window 12, and the temperature of the metal bar 10 can be detected non-contactly with a temperature measuring device. This facilitates timely adjustment of the heating power during the heat preservation process and prevents the metal bar 10 from melting due to temperature rise.

[0043] The observation window 12 is installed on the furnace door of the furnace body 1. The window of the observation window 12 corresponds to the position of the metal bar 10. The temperature measuring device measures the temperature of the metal bar 10 by aiming at the observation window 12.

[0044] In one embodiment, the magnetostrictive solid-state electromigration device further includes a control system 6 and a water-cooling system; the control system 6 is electrically connected to the vacuum system 2, the heating system and the magnetic field generating device 4, and is used to monitor and control the operating status of the vacuum system 2, the heating power and temperature of the heating system and the operating status of the magnetic field generating device 4, respectively; the furnace body 1 and the electrode rod are both provided with water-cooling jackets, and the water-cooling system is connected to the water-cooling jackets inside the furnace body 1 and the electrode rod, respectively.

[0045] The control system 6 centrally monitors and automatically controls the vacuum system 2, heating system, and magnetic field generator 4, enabling precise adjustment of vacuum level, heating power, temperature, and magnetic field strength to ensure stable and controllable purification process parameters. The water cooling system uses circulating cooling water to remove heat from the furnace body 1 and electrode rods, preventing overheating and ensuring safe and stable operation of the device for extended periods at 2000℃.

[0046] The control system 6 includes a control cabinet, a power supply cabinet, and signal transmission lines. The control cabinet is electrically connected to the vacuum system 2, the heating system, and the magnetic field generating device 4 via the signal transmission lines. The water cooling system includes a cooling circulating water system and an emergency water pipeline. The cooling circulating water system consists of a water pump, water pipes, water pipe valves, and a pressure gauge. The cooling circulating water system is connected to the water cooling jacket of the furnace body 1 and the water cooling jacket of the electrode rod via water pipes to achieve circulating cooling.

[0047] like Figure 2 As shown, according to a second aspect of an embodiment of this application, a magnetostrictive solid-state electromigration method is provided, using the above-described magnetostrictive solid-state electromigration apparatus, comprising the steps of: S1: Vertically clamp the metal bar 10 onto the electrode assembly 3 inside the furnace body 1; S2: Start vacuum system 2 to evacuate the vacuum chamber inside furnace body 1; S3: Direct current is supplied to the metal rod 10 through the electrode assembly 3 to heat up the metal rod 10 and maintain it at the solid target purification temperature. At the same time, the magnetic field generator 4 is turned on to form a ring magnetic field in the area where the metal rod 10 is located. S4: Keep the temperature and continuously evacuate the vacuum to cause the impurity atoms in the metal rod 10 to migrate directionally to one end, thus completing the solid-state electromigration purification.

[0048] Through the above steps, after establishing an ultra-high vacuum environment through vacuuming, a DC electric field and a toroidal magnetic field act together on the metal rod 10 throughout the purification process. Impurity atoms migrate directionally along the metal rod 10 under the combined influence of the electric and magnetic forces. After purification, the impurity-rich end is cut off to obtain ultra-high purity metal. After purification, the DC current and toroidal magnetic field are turned off, and the rod is removed after cooling. The entire purification process is completed in a solid state, requiring no crucible or container contact, and generating no waste liquid, waste gas, or waste residue, making it environmentally friendly.

[0049] In one specific embodiment, the vacuum system 2 is activated to evacuate the vacuum chamber inside the furnace body 1, including: sequentially activating the mechanical pump 21 and the molecular pump 22 to begin evacuation until a first vacuum level is reached in the vacuum chamber; activating the ion pump 23 to continue evacuation until a second vacuum level is reached in the vacuum chamber; and activating the titanium sublimation pump 24 to evacuate until a third vacuum level is reached in the vacuum chamber; wherein, the first vacuum level is 10. -4 Pa, the second vacuum degree is 10. -7 Pa, the third vacuum degree is 10. -8 Pa.

[0050] Example like Figure 1As shown, this embodiment provides a magnetostrictive solid-state electromigration device, including a furnace body 1, a vacuum system 2, a heating system, and a magnetic field generating device 4. The furnace body 1 has a vacuum chamber inside, and the vacuum system 2 is connected to the vacuum chamber through a vacuum pipe. The furnace body 1 is a double-layer water-cooled vertical structure, and the furnace shell is made of 304L stainless steel. The furnace body 1 is provided with a furnace door and an observation window 12. The observation window 12 is used to observe the sample inside the vacuum chamber and detect the temperature.

[0051] Vacuum system 2 consists of a four-stage pump group composed of a mechanical pump 21, a molecular pump 22, an ion pump 23, and a titanium sublimation pump 24 connected in series. The mechanical pump 21 is connected to the molecular pump 22, which is connected to the ion pump 23 via a first pneumatic baffle valve. The ion pump 23 is connected to the titanium sublimation pump 24 via a second pneumatic baffle valve. The titanium sublimation pump 24 is connected to the vacuum chamber. The vacuum chamber is equipped with a vacuum measurement interface, which is connected to a vacuum gauge. The data from the vacuum gauge is interlocked with each pneumatic baffle valve 5 and the alarm point, forming a fully automatic vacuum system.

[0052] The heating system includes a power supply and an electrode assembly 3. The electrode assembly 3 includes an electrode anode and an electrode cathode, which are respectively located at the upper and lower parts of the vacuum chamber. The electrode anode includes a water-cooled oxygen-free copper electrode rod with a water-cooled interlayer inside. A tantalum chuck is connected to the lower part of the electrode rod via a flexible connection assembly. The flexible connection assembly is a stacked structure formed by multiple 0.1mm thick tantalum sheets. The upper end of the stacked structure is fixedly connected to the electrode rod by bolts, and the lower end is fixedly connected to the tantalum chuck by bolts. The upper end of the metal rod 10 is clamped in the tantalum chuck of the electrode anode, and the lower end is clamped in the tantalum chuck of the electrode cathode. The metal rod 10 is placed vertically at the center of the vacuum chamber. The electrode assembly 3 has an adjustable lifting function to accommodate metal rods 10 of different lengths.

[0053] The magnetic field generating device 4 includes an electromagnetic coil that surrounds the outer wall of the vacuum cavity. The electromagnetic coil is made of wound copper coil and is electrically connected to the magnetic field power supply. When the electromagnetic coil is energized, it generates a ring magnetic field surrounding the metal rod 10. The magnetic field lines of the ring magnetic field are distributed along the circumference of the vacuum cavity and are perpendicular to the axial direction of the metal rod 10. That is, the direction of the ring magnetic field forms a preset angle of 90° with the direction of the current in the metal rod 10.

[0054] The inner wall of the vacuum chamber is provided with a cylindrical tungsten shielding layer 11, which surrounds the metal rod 10 and is located between the metal rod 10 and the inner wall of the vacuum chamber. The bottom of the tungsten shielding layer 11 is fixedly installed at the bottom of the vacuum chamber by a fixed flange seat.

[0055] The control system 6 includes a control cabinet, a power supply cabinet, and signal transmission lines. The control cabinet is electrically connected to the vacuum system 2, the heating system, and the magnetic field generating device 4 via the signal transmission lines, and is used to monitor and control the heating power, temperature measurement, and the operating status of the vacuum system.

[0056] The water cooling system includes a cooling circulating water system and an emergency water pipeline. The cooling circulating water system consists of a water pump, water pipes, water pipe valves, and a pressure gauge. The water cooling system is connected to the water cooling jacket of the furnace body 1 and the water cooling jacket inside the electrode rod, respectively, to remove the heat generated during the heating process.

[0057] The magnetostrictive solid-state electromigration method provided in this embodiment, using the aforementioned magnetostrictive solid-state electromigration device, includes the following steps: The metal rod 10 to be purified is vertically clamped between the electrode anode and the electrode cathode inside the furnace body 1. The upper end of the metal rod 10 is connected to the electrode anode through a tantalum clamp, and the lower end is connected to the electrode cathode through a tantalum clamp. The tantalum clamp is fixed to the flexible connection assembly by bolts.

[0058] Mechanical pump 21 and molecular pump 22 are turned on in sequence to start evacuation until the vacuum inside the furnace reaches 10. -4 Pa; turn on ion pump 23 and continue pumping high vacuum until the vacuum level reaches 10. -7 Pa; turn on the titanium sublimation pump 24 to draw a high vacuum, so that the vacuum chamber reaches an ultra-high vacuum environment.

[0059] Turn on the heating power supply and slowly increase the current to supply direct current to the metal rod 10 through the anode and cathode electrodes, causing the metal rod 10 to heat up and maintain at the target solid-state purification temperature, which can reach up to 2000℃, and then begin heat preservation. At the same time, turn on the magnetic field power supply and set the magnetic field current and voltage parameters until the magnetic field strength reaches the set value. The electromagnetic coil forms a ring magnetic field around the metal rod 10, and the direction of the ring magnetic field is perpendicular to the direction of the current.

[0060] Under the combined action of the electric field generated by direct current and the ring magnetic field, the metal rod is kept at a constant temperature and continuously evacuated for up to 100 hours. Impurity atoms migrate directionally along the metal rod 10 under the combined action of electric and magnetic forces, accumulating at the anode or cathode end of the metal rod 10.

[0061] After the heat preservation is completed, turn off the heating power supply and magnetic field power supply, and turn off all pump groups and valves of the vacuum system. After cooling, take out the metal rod 10 and cut off the part with high impurity content at the end to obtain the purified ultra-high purity metal.

[0062] It will be readily understood by those skilled in the art that the aforementioned advantageous methods can be freely combined and superimposed without conflict.

[0063] The above are merely preferred embodiments of this application and are not intended to limit this application. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of this application should be included within the protection scope of this application. The above are merely implementation methods of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of this application, and these improvements and modifications should also be considered within the protection scope of this application.

Claims

1. A magnetostrictive solid-state electromigration device, characterized in that, include: The furnace body comprises a vacuum system, a heating system, and a magnetic field generating device; the furnace body has a vacuum chamber inside, and the vacuum system is connected to the vacuum chamber; the heating system includes an electrode assembly disposed inside the furnace body, the electrode assembly clamping a metal bar and supplying it with direct current; The magnetic field generating device is arranged around the vacuum cavity to generate a ring magnetic field around the metal bar. The annular magnetic field is configured to have a preset angle with the direction of the current in the metal rod, so that the annular magnetic field and the electric field generated by the direct current jointly drive the directional migration of impurity atoms in the metal rod.

2. The magnetostrictive solid-state electromigration device according to claim 1, characterized in that, The vacuum system includes a mechanical pump, a molecular pump, an ion pump, and a titanium sublimation pump, which are connected in series to form a four-stage pump group.

3. The magnetostrictive solid-state electromigration device according to claim 1, characterized in that, It also includes a pneumatic baffle valve, which is installed on the vacuum pipeline between the vacuum system and the furnace body; the vacuum chamber is provided with a vacuum measurement interface, which is connected to a vacuum gauge.

4. The magnetostrictive solid-state electromigration device according to claim 1, characterized in that, The electrode assembly includes an electrode rod, a clamp, and a flexible connection assembly. The flexible connection assembly is disposed between the electrode rod and the clamp. The flexible connection assembly has a stacked structure comprising multiple flexible connecting sheets and is configured to absorb the displacement of the bar stock due to thermal expansion or contraction by interlayer relative sliding or deformation of the stacked structure.

5. The magnetostrictive solid-state electromigration device according to claim 4, characterized in that, The flexible connecting piece is a tantalum sheet, and multiple tantalum sheets are stacked to form the laminated structure; wherein, one end of the laminated structure is fixedly connected to the electrode rod by bolts, and the other end is fixedly connected to the clamp by bolts.

6. The magnetostrictive solid-state electromigration device according to claim 1, characterized in that, The inner wall of the vacuum chamber is provided with a tungsten shielding layer, which is fixed to the vacuum chamber by a fixed flange seat at the bottom.

7. The magnetostrictive solid-state electromigration device according to claim 4, characterized in that, It also includes a control system and a water cooling system; the control system is electrically connected to the vacuum system, the heating system and the magnetic field generating device, and is used to monitor and control the operating status of the vacuum system, the heating power and temperature of the heating system and the operating status of the magnetic field generating device, respectively; the furnace body and the electrode rod are both provided with water cooling jackets, and the water cooling system is connected to the water cooling jackets inside the furnace body and the electrode rod, respectively.

8. The magnetostrictive solid-state electromigration device according to claim 1, characterized in that, The magnetic field generating device includes an electromagnetic coil surrounding the vacuum cavity; wherein the preset included angle is 90°, and the direction of the annular magnetic field generated by the electromagnetic coil is perpendicular to the direction of the current in the metal rod.

9. A magnetostrictive solid-state electromigration method, using the magnetostrictive solid-state electromigration apparatus as described in any one of claims 1 to 8, characterized in that, include: The metal bars are vertically clamped onto the electrode assembly inside the furnace; Start the vacuum system to evacuate the vacuum chamber inside the furnace; Direct current is supplied to the metal rod through the electrode assembly to heat the metal rod and maintain it at the solid target purification temperature. At the same time, the magnetic field generator is turned on to form a ring magnetic field in the area where the metal rod is located. By maintaining the temperature and continuously drawing a vacuum, impurity atoms in the metal rod are directionally migrated to one end, thus completing solid-state electromigration purification.

10. The magnetostrictive solid-state electromigration method according to claim 9, characterized in that, The activation of the vacuum system, which evacuates the vacuum chamber inside the furnace, includes: The mechanical pump and molecular pump are turned on in sequence to start evacuating the vacuum until the first vacuum level is reached in the vacuum chamber. Turn on the ion pump and continue evacuating the vacuum until the second vacuum level is reached in the vacuum chamber. Turn on the titanium sublimation pump to evacuate until the vacuum chamber reaches the third vacuum level; The first vacuum degree is 10. -4 Pa, the second vacuum degree is 10 -7 Pa, the third vacuum degree is 10 -8 Pa.

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