X-ray generating device

Abstract

The invention provides an X-ray generating device which comprises a cathode system, a magnetic deflection system, a magnetic focusing system, an anode system and a vacuumizing system, the cathode system comprises a cathode cavity, a cathode high-voltage assembly and a high-voltage connecting assembly, and the cathode high-voltage assembly comprises a lanthanum hexaboride filament assembly; the magnetic deflection system comprises a magnetic deflection unit; the magnetic focusing system comprises a quadrupole focusing unit and a monopole focusing unit; the anode system comprises an anode target assembly, the anode target assembly comprises a transmission target, and electron beams emitted by the lanthanum hexaboride filament assembly sequentially pass through the magnetic deflection unit, the quadrupole focusing unit and the monopole focusing unit to reach the transmission target. According to the X-ray generation device, the lanthanum hexaboride lamp filament with a smaller emission plane is used as a heat emission source, the two combined focusing units are used for highly compressing the electron beam, and a high vacuum environment is provided, so that the focal point finally irradiated on the transmission target is extremely small, and the resolution ratio and the stability of the X-ray generation device are improved.

Description

Technical Field

[0001] This invention belongs to the field of X-ray technology and relates to an X-ray generating device. Background Technology

[0002] An X-ray tube is an X-ray output source that produces X-rays for non-destructive testing of the interior of objects, finding widespread application in various fields such as medical treatment, security inspection, and industrial flaw detection. In an X-ray tube, an electron beam generated by the cathode system is accelerated by the high-voltage electric fields at both ends of the cathode and anode systems before entering the optical path adjustment system. Under the control of functional components responsible for deflection and focusing within the optical path adjustment system, the beam's trajectory is adjusted, ultimately striking the anode target surface in the anode system. The high-energy electron beam striking the anode target surface generates X-rays through bremsstrahlung. An external high-voltage power supply outputs a stable high-voltage electric field between the cathode and anode systems, and the external casing vacuum-encapsulates the entire device to provide a high-vacuum environment, ensuring continuous and stable operation of the electron beam impact event, ultimately resulting in a continuously and stably outputting X-rays.

[0003] Existing technology has developed open-type X-ray sources with a maximum voltage of 160 kV and a minimum image resolution of approximately 0.9 μm. In the global semiconductor packaging market, advanced packaging accounts for an increasingly larger share, thus demanding high-resolution, non-destructive, and dynamic analysis capabilities for detection technologies. Therefore, a new type of X-ray generator is needed to achieve even higher resolution.

[0004] It should be noted that the above introduction to the technical background is only for the purpose of providing a clear and complete explanation of the technical solutions of this application and facilitating understanding by those skilled in the art. It should not be assumed that these technical solutions are known to those skilled in the art simply because they have been described in the background section of this application. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide an X-ray generating device to solve the problem of low resolution in existing X-ray generating devices.

[0006] To achieve the above and other related objectives, the present invention provides an X-ray generating apparatus, comprising:

[0007] A cathode system includes a cathode cavity, a cathode high-voltage assembly, and a high-voltage connection assembly. The cathode high-voltage assembly is located in the cathode cavity. One end of the high-voltage connection assembly is connected to the cathode high-voltage assembly, and the other end is connected to a high-voltage power supply. The cathode high-voltage assembly includes a lanthanum hexaboride filament assembly.

[0008] A magnetic deflection system is connected to the cathode system, and the magnetic deflection system includes a magnetic deflection unit;

[0009] Magnetic focusing systems include quadrupole focusing units and monopole focusing units;

[0010] An anode system is connected to the monopolar focusing unit. The anode system includes an anode target assembly, which includes a transmission target. An electron beam emitted by the lanthanum hexaboride filament assembly passes sequentially through the magnetic deflection unit, the quadrupole focusing unit, and the monopolar focusing unit to reach the transmission target.

[0011] The vacuum system is connected to the cathode system, the magnetic deflection system, the magnetic focusing system, and the anode system.

[0012] Optionally, the high-voltage connection assembly includes a high-voltage cable connector, a ceramic socket, and a sealing structure. The high-voltage cable connector is sealed to one end of the cathode cavity. The high-voltage cable connector is provided with a grid high-voltage wire and a filament high-voltage wire. One end of the ceramic socket is connected to the cathode high-voltage assembly, and the other end is connected to the high-voltage cable connector through the sealing structure. The sealing structure is filled with insulating oil.

[0013] Optionally, the cathode high-voltage assembly further includes a gate assembly, a gate post, and a filament post. The gate assembly includes a gate hole. The gate post, the filament post, and the lanthanum hexaboride filament assembly are all located between the gate assembly and the ceramic socket. The gate post and the filament post are respectively connected to the ceramic socket. The lanthanum hexaboride filament assembly is connected to the filament high-voltage line through the filament post. The gate assembly is connected to the gate high-voltage line through the gate post.

[0014] Optionally, the cathode system further includes an anode plate located at the upper end of the cathode cavity, the magnetic deflection unit is located above the cathode system and connected to the anode plate, the magnetic deflection unit includes a deflection lens and a deflection lens housing that encloses the deflection lens, the deflection lens includes two sets of coils respectively disposed in a first direction and a second direction, the first direction is perpendicular to the second direction, and the plane containing the first direction and the second direction is perpendicular to the movement path of the electron beam.

[0015] Optionally, the quadrupole focusing unit includes a quadrupole focusing lens and a quadrupole focusing lens housing that encloses the quadrupole focusing lens. The quadrupole focusing lens includes two sets of coils respectively disposed in a third direction and a fourth direction. The third direction is perpendicular to the fourth direction, and the plane containing the third direction and the fourth direction is perpendicular to the motion path of the electron beam.

[0016] Optionally, the monopolar focusing unit is connected to the quadrupole focusing lens housing. The monopolar focusing unit includes a monopolar focusing lens, a pole shoe structure, and a pole shoe cover. The pole shoe cover is located above and connected to the pole shoe structure. The pole shoe structure and the pole shoe cover are closed to form a cavity, and the monopolar focusing lens is located in the cavity.

[0017] Optionally, a vacuum cavity is provided between the magnetic deflection system and the magnetic focusing system, with one end of the vacuum cavity connected to the quadrupole focusing lens housing and the other end connected to the pole shoe cover;

[0018] The vacuum system includes an ion pump, a getter pump, and a vacuum valve. The ion pump and the vacuum valve are both located on the outer wall of the cathode cavity and communicate with the cathode cavity. The getter pump is located in the vacuum cavity.

[0019] Optionally, the anode target assembly further includes a target cooling cover and a limiting aperture. The target cooling cover is provided with cooling water channels, and the transmission target is provided with a reserved rotation hole. The limiting aperture includes an aperture opening. The transmission target is located between the target cooling cover and the limiting aperture. The transmission target is connected to the limiting aperture through a sealing ring. The electron beam emitted by the lanthanum hexaboride filament assembly passes through the limiting aperture and reaches the transmission target through the aperture opening.

[0020] Optionally, the anode system further includes a non-magnetic titanium tube, which is inserted into the cavity formed by the pole shoe structure and the closed pole shoe cover through the top opening of the pole shoe cover, and the limiting aperture is located in the channel of the non-magnetic titanium tube.

[0021] Optionally, the connection between the cathode system and the magnetic deflection system includes indium metal cold pressing welding, the connection between the magnetic focusing system and the pole shoe structure includes indium metal cold pressing welding, and the connection between the pole shoe structure and the pole shoe cover includes indium metal cold pressing welding.

[0022] As described above, the X-ray generating device of the present invention includes a cathode system, a magnetic deflection system, a magnetic focusing system, an anode system, and a vacuum system. The cathode system includes a cathode cavity, a cathode high-voltage assembly, and a high-voltage connection assembly. The cathode high-voltage assembly is located within the cathode cavity. One end of the high-voltage connection assembly is connected to the cathode high-voltage assembly, and the other end is connected to a high-voltage power supply. The cathode high-voltage assembly includes a lanthanum hexaboride filament assembly. The magnetic deflection system is connected to the cathode system and includes a magnetic deflection unit. The magnetic focusing system includes a quadrupole focusing unit and a monopole focusing unit. The anode system is connected to the monopole focusing unit and includes an anode target assembly. The anode target assembly includes a transmission target. The electron beam emitted by the lanthanum hexaboride filament assembly sequentially passes through the magnetic deflection unit, the quadrupole focusing unit, and the monopole focusing unit to reach the transmission target. The vacuum system is connected to the cathode system, the magnetic deflection system, the magnetic focusing system, and the anode system. The X-ray generating apparatus of the present invention improves the resolution and stability of the X-ray generating apparatus by using a lanthanum hexaboride filament with a smaller emission plane as a thermal emission source and by using two combined focusing units to highly compress the electron beam and provide a high vacuum environment, so that the focal point that finally hits the transmission target is extremely small. Attached Figure Description

[0023] Figure 1 The diagram shown is a structural schematic of an embodiment of the X-ray generating apparatus of the present invention.

[0024] Figure 2 The diagram shown is a structural schematic of the cathode high-voltage assembly in one embodiment of the X-ray generating apparatus of the present invention.

[0025] Figure 3 The diagram shown is a structural schematic of the anode target assembly in one embodiment of the X-ray generating apparatus of the present invention.

[0026] Figure 4 The diagram shown is a structural schematic of the cooling water channel in one embodiment of the X-ray generating apparatus of the present invention.

[0027] Explanation of reference numerals in the attached figures

[0028] 11 cathode cavity 12 Cathode high voltage assembly 121 Lanthanum hexaboride filament assembly 122 Gate components 123 Gate pillar 124 Filament insert 125 Gate hole 13 High voltage connection components 131 High-voltage cable joint 132 ceramic socket 133 Sealed structure 134 Gate high voltage line 135 Filament high voltage wire 14 anode plate 21 Deflection unit 211 Deflecting lens 212 Deflecting lens housing 31 Quad-Electrode Focusing Unit 311 Quadrupole focusing lens 312 Quadrupole focusing lens housing 41 Anode target assembly 411 Transmission target 4111 Reserved rotating hole 412 Target cooling cover 413 Limiting aperture 414 Non-magnetic titanium tube 415 cooling water channel 4151 Inlet 4152 water outlet 4131 Aperture 51 vacuum chamber 52 Ion pump 52 getter pump 54 Vacuum valves 61 High voltage power supply 62 electron beam Detailed Implementation

[0029] The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention.

[0030] It should be emphasized that the term "including / comprises" as used herein refers to the presence of a feature, whole, step, or component, but does not exclude the presence or addition of one or more other features, wholes, steps, or components.

[0031] Features described and / or illustrated for one embodiment may be used in the same or similar manner in one or more other embodiments, combined with features in other embodiments, or substituted for features in other embodiments.

[0032] In the detailed description of embodiments of the present invention, for ease of explanation, the schematic diagrams illustrating the device structure may be partially enlarged without adhering to the general scale, and the schematic diagrams are merely examples and should not limit the scope of protection of the present invention. Furthermore, in actual manufacturing, the three-dimensional spatial dimensions of length, width, and depth should be included.

[0033] For ease of description, spatial relation terms such as “below,” “under,” “lower than,” “below,” “above,” and “upper” may be used herein to describe the relationship between one element or feature shown in the accompanying drawings and other elements or features. It will be understood that these spatial relation terms are intended to include directions other than those depicted in the drawings for devices in use or operation. Furthermore, when a layer is referred to as being “between” two layers, it may be the only layer between the two layers, or there may be one or more layers in between.

[0034] In the context of this application, the structure described above the first feature may include embodiments in which the first and second features are in direct contact, or embodiments in which additional features are formed between the first and second features, such that the first and second features may not be in direct contact.

[0035] It should be noted that the illustrations provided in this embodiment are only schematic representations of the basic concept of the present invention. Therefore, the illustrations only show the components related to the present invention and are not drawn according to the actual number, shape and size of the components in the actual implementation. In the actual implementation, the form, quantity and proportion of each component can be arbitrarily changed, and the layout of the components may also be more complex.

[0036] Please see Figure 1The diagram shows a schematic representation of the X-ray generating device of the present invention in one embodiment, including a cathode system, a magnetic deflection system, a magnetic focusing system, an anode system, and a vacuum system. The cathode system includes a cathode cavity 11, a cathode high-voltage assembly 12, and a high-voltage connection assembly 13. The cathode high-voltage assembly 12 is located within the cathode cavity 11. One end of the high-voltage connection assembly 13 is connected to the cathode high-voltage assembly 12, and the other end is connected to a high-voltage power supply 61. The cathode high-voltage assembly 12 includes a lanthanum hexaboride filament assembly 121. The magnetic deflection system is connected to the cathode system. The magnetic deflection system includes a magnetic deflection unit 21; the magnetic focusing system includes a quadrupole focusing unit 31 and a unipolar focusing unit 32; the anode system is connected to the magnetic focusing system, and the anode system includes an anode target assembly 41, which includes a transmission target 411. The electron beam 62 emitted by the lanthanum hexaboride filament assembly 121 passes sequentially through the magnetic deflection unit 21, the quadrupole focusing unit 31, and the unipolar focusing unit 32 to reach the transmission target 411; the vacuum system is connected to the cathode system, the magnetic deflection system, the magnetic focusing system, and the anode system.

[0037] As an example, the lanthanum hexaboride filament assembly 121 in the cathode high-voltage assembly 12 generates the electron beam 62. After being accelerated by a high-voltage electric field, the electron beam 62 enters the magnetic deflection system and is adjusted by the magnetic deflection unit 21 in either the X or Y direction. Subsequently, the electron beam 62 enters the magnetic focusing system and is compressed by the quadrupole focusing unit 31 and the monopole focusing unit 32 to reduce its diameter. Finally, the electron beam 62 strikes the transmission target 411 in the anode system and generates X-rays through bremsstrahlung. During the process from the generation of the electron beam 62 to its impact on the transmission target 411, the high-voltage power supply 61 outputs a stable high-voltage electric field between the cathode and anode systems via the high-voltage connection assembly 13. The vacuum system provides an ultra-high vacuum environment for the internal cavity of the entire X-ray generator, thereby enabling the electron beam 62 impact event to operate continuously and stably, ultimately resulting in a continuously and stably outputting X-ray.

[0038] This invention employs a lanthanum hexaboride filament as the thermal emission source. Compared to traditional forked tungsten filaments, the lanthanum hexaboride filament offers higher brightness while having a smaller emission plane. This characteristic allows the electron beam 62 emitted by the lanthanum hexaboride filament to have a smaller effective focal point, which helps improve the resolution of the X-ray generator and thus enhances the clarity of X-ray imaging. Furthermore, compared to traditional forked tungsten filaments, the lanthanum hexaboride filament also has a longer lifespan, helping to reduce replacement frequency. To meet the high vacuum environment requirements of the lanthanum hexaboride filament, a vacuum system is used to evacuate the interior of the X-ray generator. The various systems of the X-ray generator are connected by cold-press welding, achieving an internal vacuum level of up to 10...-9 The ultra-high vacuum level of Pa ensures the stability of the X-rays emitted by the X-ray generator.

[0039] The present invention employs a magnetic focusing system composed of the quadrupole focusing unit 31 and the monopole focusing unit 32 to highly compress the electron beam 62 emitted by the lanthanum hexaboride filament, thereby reducing the diameter of the electron beam 62. The quadrupole focusing unit 31 is used for initial compression, and the monopole focusing unit 32 is used for further compression, so that the focal point that finally hits the transmission target 411 is extremely small, thereby further improving the resolution of the X-ray generating device and thus improving the clarity of X-ray imaging.

[0040] The X-ray generating device of the present invention first reduces the diameter of the emitted electron beam 62 by using a lanthanum hexaboride filament, and then uses two combined focusing units to highly compress the electron beam 62 in the emission path to further reduce the diameter of the electron beam 62, while providing an ultra-high vacuum environment, so that the focal point that finally hits the transmission target 411 is extremely small, thereby improving the resolution and stability of the X-ray generating device.

[0041] The X-ray generating device of the present invention can be used for the inspection of semiconductor packaging structures, and has the advantages of high resolution, non-destructive nature and dynamic analysis capability, thereby meeting the demand of the semiconductor packaging technology field for higher accuracy of the inspection technology performed by the X-ray generating device.

[0042] It should be noted that the X-ray generating device of the present invention is not limited to the detection of semiconductor packaging structures, but can also be applied to other occasions that require X-ray detection, such as in the food industry for detecting foreign objects in food, in the medical technology field for examining diseases such as fractures, and in the manufacturing industry for detecting defects such as cracks and pores inside materials.

[0043] As an example, such as Figure 1As shown, the high-voltage connection assembly 13 includes a high-voltage cable connector 131, a ceramic socket 132, and a sealing structure 133. The high-voltage cable connector 131 is sealed to one end of the cathode cavity 11, and a grid high-voltage wire 134 and a filament high-voltage wire 135 are disposed inside the high-voltage cable connector 131. One end of the ceramic socket 132 is connected to the cathode high-voltage assembly 12, and the other end is connected to the high-voltage cable connector 131 through the sealing structure 133. The sealing structure 133 is filled with insulating oil. Both the high-voltage cable connector 131 and the ceramic socket 132 are connected to the cathode cavity 11 by welding, and the sealing structure 133 is isolated from the cathode cavity 11. As an example, to ensure stable output of high voltage and filament current, the high-voltage connection assembly 13, composed of the high-voltage cable connector 131, the ceramic socket 132, and the sealing structure 133, is connected to the cathode cavity 11 in a closed manner. One end of the ceramic socket 132 is connected to the cathode high-voltage assembly 12 in the cathode cavity 11, and one end of the high-voltage cable connector 131 is connected to the end of the ceramic socket 132 facing away from the cathode high-voltage assembly 12, while the other end is connected to the high-voltage power supply 61. Due to dimensional constraints, the portion where the ceramic socket 132 and the high-voltage cable connector 131 connect has excess space. Filling this space with insulating oil can expel air between the high-voltage cable connector 131 and the ceramic socket 132, preventing high-voltage discharge.

[0044] By filling the sealing structure 133 with insulating oil, the withstand voltage rating of the device can be improved, and the stability of the X-ray generation can be enhanced, ensuring that discharge phenomena will not occur due to the presence of air or impurities. Compared with applying insulating silicone grease between the high-voltage cable connector 131 and the ceramic socket 132, filling the sealing structure 133 between the high-voltage cable connector 131 and the ceramic socket 132 with insulating oil can dissipate the heat generated by the device during operation more quickly. Moreover, there is no need for regular maintenance of the sealing structure 133, eliminating routine maintenance steps.

[0045] In some embodiments, such as Figure 1 As shown, the high-voltage cable connector 131 is internally provided with two grid high-voltage wires 134 and one filament high-voltage wire 135. Each grid high-voltage wire 134 and each filament high-voltage wire 135 is connected to the high-voltage power supply 61 at one end and to the cathode high-voltage assembly 12 at the other end.

[0046] In some embodiments, the ceramic socket 132 is sintered using special ceramics, resulting in a dense structure. After sintering, the surface of the ceramic socket 132 is precision-machined to control its surface roughness within a certain range, which can significantly reduce the probability of creepage on the surface of the ceramic socket 132 under high-voltage conditions.

[0047] Please see Figure 2 The diagram shows a schematic representation of the cathode high-voltage assembly 121 in an embodiment of the X-ray generating apparatus of the present invention, including the lanthanum hexaboride filament assembly 121, the gate assembly 122, the gate post 123, and the filament insert 124. The gate assembly 122 includes a gate hole 125. The gate post 123, the filament insert 124, and the lanthanum hexaboride filament assembly 121 are all located between the gate assembly 122 and the ceramic socket 132. The lanthanum hexaboride filament assembly 121 faces the gate hole 125. The gate post 123 and the filament insert 124 are respectively connected to the ceramic socket 132. The lanthanum hexaboride filament assembly 121 is connected to the filament high-voltage line 135 through the filament insert 124. The gate assembly 122 is connected to the gate high-voltage line 134 through the gate post 123.

[0048] As an example, such as Figure 1 and Figure 2 As shown, the cathode high-voltage assembly 12 is located inside the cathode cavity 11. The gate assembly 122 is connected to the ceramic socket 132 and forms a space to accommodate the gate post 123, the filament insert 124, and the lanthanum hexaboride filament assembly 121. The gate post 123 and the filament insert 124 are both connected to the ceramic socket 132. Two filament inserts 124 are distributed on both sides of the gate post 123, and the lanthanum hexaboride filament assembly 121 is positioned opposite the gate post 123 and the filament insert 124 at the other end of the space. One end of the gate post 123 is connected to the gate assembly 122, and the other end is connected to the gate high-voltage line 134. One end of each filament insert 124 is connected to the lanthanum hexaboride filament assembly 121, and the other end is connected to the filament high-voltage line 135. A small circular hole is formed at the center of the gate assembly 122 as the gate hole 125. The electron beam 62 emitted by the lanthanum hexaboride filament assembly 121 is accelerated by the high-voltage electric field between the anode plate 14 located at the upper end of the cathode cavity 11 and the gate assembly 122 in the cathode system, and then enters the magnetic deflection system and the magnetic focusing system through the gate hole 125 in sequence, and finally hits the transmission target 411.

[0049] In some embodiments, the gate post 123 and the filament post 124 are made of Kovar alloy and are vacuum brazed to the ceramic socket 132. The gate assembly 122 is made of high-quality stainless steel and coated with a high emissivity coating to better radiate heat in a vacuum environment, reducing the heat of the component itself.

[0050] As an example, such as Figure 1 As shown, the magnetic deflection unit 21 is located above the cathode system and connected to the anode plate 14. The magnetic deflection unit 21 includes a deflection lens 211 and a deflection lens housing 212 enclosing the deflection lens 211. The deflection lens 211 includes two sets of coils respectively disposed in a first direction and a second direction. The first direction is perpendicular to the second direction, and the plane containing the first and second directions is perpendicular to the path of the electron beam (i.e., the plane formed by the combination of the first and second directions is perpendicular to the path of the electron beam). Figure 1 The two-dimensional planar diagram shown is located in a plane perpendicular to the plane. Each group of coils is symmetrically distributed in the first or second direction, and the excitation direction of each group of coils is consistent in the same direction. The deflection lens 211 can adjust the deflection direction of the electron beam 62 to ensure the collimation of the electron beam 62 and ensure that the electron beam 62 is correctly injected into the transmission target 411. The deflection lens housing 212 is a protective cover for the deflection lens 211, which can shield the outside of the deflection lens 211 from interfering magnetic fields, thereby reducing the influence of external magnetic fields on the magnetic field of the deflection lens 211.

[0051] In some embodiments, the deflection lens housing 212 is made of a material with high magnetic permeability, which can shield external magnetic fields to the greatest extent and avoid interfering with the deflection magnetic field.

[0052] As an example, such as Figure 1 As shown, the quadrupole focusing unit 31 includes a quadrupole focusing lens 311 and a quadrupole focusing lens housing 312 enclosing the quadrupole focusing lens 311. The quadrupole focusing lens 311 includes two sets of coils respectively disposed in a third direction and a fourth direction. The third direction is perpendicular to the fourth direction, and the plane containing the third direction and the fourth direction is perpendicular to the motion path of the electron beam (i.e., the plane formed by the combination of the third direction and the fourth direction is perpendicular to the motion path of the electron beam). Figure 1The two-dimensional planar diagram shown is located in a plane perpendicular to the plane. Each group of coils is symmetrically distributed in the third or fourth direction, and the excitation directions of each group of coils in the same direction are opposite. The quadrupole focusing lens 311 is used to initially compress the diameter of the electron beam 62 to reduce the diameter of the electron beam 62. The quadrupole focusing lens housing 312 is a protective cover for the quadrupole focusing lens 311, which can shield the outside of the quadrupole focusing lens 311 from interfering magnetic fields, thereby avoiding the influence of external magnetic fields on the magnetic field of the quadrupole focusing lens 311.

[0053] In some embodiments, the quadrupole focusing lens housing 312 is made of a material with high magnetic permeability, which can shield external magnetic fields to the greatest extent and avoid interfering with the focusing magnetic field.

[0054] In some embodiments, the first direction and the third direction indicate the same direction. In other embodiments, the first direction and the third direction indicate different directions.

[0055] Because the quadrupole focusing lens 311 can only compress the length of the electron beam 62 to the required range in one of the third and fourth directions, but cannot compress the length of the electron beam 62 to the required range in the other direction, the present invention further provides a monopole focusing unit 32 used in combination with the quadrupole focusing unit 31 to further compress the electron beam 62.

[0056] As an example, such as Figure 1 As shown, the monopolar focusing unit 32 is located above and connected to the quadrupole focusing unit 31. The monopolar focusing unit 32 includes a monopolar focusing lens 321, a pole shoe structure 322, and a pole shoe cover 323. The pole shoe cover 323 is located above and connected to the pole shoe structure 322. The pole shoe structure 322 and the pole shoe cover 323 close to form a cavity, and the monopolar focusing lens 321 is located within the cavity. The monopolar focusing lens 321, in conjunction with the strong magnetic lens of the pole shoe structure 322 and the pole shoe cover 323, can ultimately compress the electron beam 62, which has been compressed by the quadrupole focusing unit 31, so that the length of the electron beam 62 in both the third and fourth directions reaches the required value.

[0057] In some embodiments, both the pole shoe structure 322 and the pole shoe cover 323 are made of electrical pure iron. Hydrogenation and annealing heat treatment of the material during processing can make the induced magnetic field generated by the pole shoe structure 322 and the pole shoe cover 323 more uniform, reducing the astigmatism of the magnetic lens.

[0058] Please see Figure 3The diagram shows a schematic representation of the anode target assembly 41 in an embodiment of the X-ray generating apparatus of the present invention, including the transmission target 411, a target cooling cover 412, a limiting aperture 413, and a non-magnetic titanium tube 414. The electron beam 62 emitted from the lanthanum hexaboride filament assembly 121 passes through the limiting aperture 413 and reaches the transmission target 411 through the aperture opening.

[0059] As an example, such as Figure 1 and Figure 3 As shown, the non-magnetic titanium tube 414 is inserted into the cavity formed by the closed structure of the pole shoe structure 322 and the pole shoe cover 323 through the top opening of the pole shoe cover 323. The target cooling cover 412 is located above the non-magnetic titanium tube 414, and a cooling water channel 415 is provided on the target cooling cover 412.

[0060] For example, please refer to Figure 4 The diagram shows a schematic of the cooling water channel 415 in one embodiment of the X-ray generating device of the present invention. The cooling water channel 415 is provided with an inlet 4151 and an outlet 4152. By circulating water through the cooling water channel 415, the anode target assembly 41 can be cooled.

[0061] As an example, such as Figure 1 and Figure 3 As shown, the limiting aperture 413 is located within the non-magnetic titanium tube 414, which provides support for the limiting aperture 413. The upper and lower parts of the limiting aperture 413 are designed with an eccentric structure. An opening 4131 is formed at the center of the limiting aperture 413. The central axis of the opening 4131 coincides with the central axis of the lower part of the limiting aperture 413 and the central axis of the X-ray generator. The central axis of the X-ray generator represents the ideal trajectory of the electron beam 62.

[0062] As an example, such as Figure 1 and Figure 3 As shown, the transmission target 411 is located between the target cooling cover 412 and the limiting aperture 413, and the transmission target 411 is connected to the limiting aperture 413. The transmission target 411 has a reserved rotation hole 4111. When the electron beam 62 bombards the target surface of the transmission target 411 for a long time, the target surface will be damaged and aged. At this time, a target rotation operation is required to change the position of the electron beam 62 hitting the target. The target rotation operation can be performed by using the reserved rotation hole and suitable tooling to rotate the transmission target 411, thereby changing the position of the electron beam 62 hitting the target.

[0063] In some embodiments, the transmission target 411 is made of diamond.

[0064] In some embodiments, the transmission target 411 is connected to the limiting aperture 413 via a sealing ring to facilitate target rotation.

[0065] As an example, such as Figure 1 As shown, a vacuum chamber 51 is provided between the magnetic deflection system and the magnetic focusing system. One end of the vacuum chamber 51 is connected to the quadrupole focusing lens housing 312, and the other end is connected to the pole shoe cover 323. The vacuum system includes an ion pump 52, a getter pump 53, and a vacuum valve 54. The ion pump 52 and the vacuum valve 54 are both located on the outer wall of the cathode cavity 11 and communicate with the cathode cavity 11. The getter pump 53 is located in the vacuum chamber 51. By using the ion pump 52 and the getter pump 53 in combination to evacuate the internal cavity of the X-ray generator, the internal cavity can be rapidly brought to an ultra-high vacuum (theoretically reaching a value of 10). -9 (Ultra-high vacuum of Pa). Since the ion pump 52 and the getter pump 53 used in the X-ray generating device both have pressure requirements for startup (requiring a pressure less than 10 Pa),... -2 (It can only be started when Pa), therefore, a vacuum valve 54 is installed on the outer wall of the cathode cavity 11 to evacuate the internal cavity of the X-ray generator by connecting an external vacuum pump (which can achieve a vacuum level of 10 Pa). -2 (below Pa). After the X-ray generating device is assembled, an external vacuum pump is used to evacuate the internal cavity of the X-ray generating device through the vacuum valve 54. Once the required vacuum level is reached, the ion pump 52 and the suction meter pump 53 can be started, and the vacuum valve 54 can be closed and the external vacuum pump removed.

[0066] In some embodiments, the outer wall of the cathode cavity 11 where the ion pump 52 is located and the outer wall of the cathode cavity 11 where the vacuum valve 54 is located are located on opposite sides of the cathode cavity 11.

[0067] As an example, to maintain the internal vacuum of the X-ray generator, the various structural components are cold-pressed together using indium sheets. This welding method has a low leakage rate (less than 10%). -11 Pa·m 3 / s) and safe and reliable characteristics. The connection methods of the cathode cavity 11 and the anode plate 14 in the cathode system, the connection method of the anode plate 14 in the cathode system and the deflection lens housing 212 in the magnetic deflection system, the connection method between the quadrupole focusing lens housing 312 and the pole shoe structure 322 in the magnetic focusing system, and the connection method between the pole shoe structure 322 and the pole shoe cover 323 are all indium cold pressing welding.

[0068] In some embodiments, both the cathode cavity 11 and the vacuum cavity 51 are made of high-quality materials with low outgassing rates. High-gloss treatment of the inner surface of the material can further reduce the outgassing rate in ultra-high vacuum environments.

[0069] The X-ray generator of this invention is a semi-enclosed X-ray source with a maximum voltage of 160 kV. The X-ray generator employs a lanthanum hexaboride filament with a smaller emission plane as the hot emission source and uses two combined focusing units to highly compress the electron beam 62, providing a high vacuum environment. This results in an extremely small focal point that ultimately hits the transmission target 411, thereby improving the resolution and stability of the X-ray generator. The optimal image resolution of the X-ray generator can reach 0.5 μm, and the maximum power is 20 W. Furthermore, its high voltage and tube current output are more stable, making it suitable for long-term online packaging and inspection.

[0070] In summary, the X-ray generating device of the present invention includes a cathode system, a magnetic deflection system, a magnetic focusing system, an anode system, and a vacuum system. The cathode system includes a cathode cavity, a cathode high-voltage assembly, and a high-voltage connection assembly. The cathode high-voltage assembly is located within the cathode cavity. One end of the high-voltage connection assembly is connected to the cathode high-voltage assembly, and the other end is connected to a high-voltage power supply. The cathode high-voltage assembly includes a lanthanum hexaboride filament assembly. The magnetic deflection system is connected to the cathode system and includes a magnetic deflection unit. The magnetic focusing system includes a quadrupole focusing unit and a monopole focusing unit. The anode system is connected to the monopole focusing unit and includes an anode target assembly. The anode target assembly includes a transmission target. The electron beam emitted by the lanthanum hexaboride filament assembly sequentially passes through the magnetic deflection unit, the quadrupole focusing unit, and the monopole focusing unit to reach the transmission target. The vacuum system is connected to the cathode system, the magnetic deflection system, the magnetic focusing system, and the anode system. The X-ray generating apparatus of this invention improves the resolution and stability of the X-ray generating apparatus by employing a lanthanum hexaboride filament with a smaller emission plane as the thermal emission source and by using two combined focusing units to highly compress the electron beam and provide a high vacuum environment, resulting in an extremely small focal point that ultimately hits the transmission target. Therefore, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0071] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. An X-ray generating device, characterized in that, include: A cathode system includes a cathode cavity, a cathode high-voltage assembly, and a high-voltage connection assembly. The cathode high-voltage assembly is located in the cathode cavity. One end of the high-voltage connection assembly is connected to the cathode high-voltage assembly, and the other end is connected to a high-voltage power supply. The cathode high-voltage assembly includes a lanthanum hexaboride filament assembly. A magnetic deflection system is connected to the cathode system, and the magnetic deflection system includes a magnetic deflection unit; Magnetic focusing systems include quadrupole focusing units and monopole focusing units; An anode system is connected to the monopolar focusing unit. The anode system includes an anode target assembly, which includes a transmission target. An electron beam emitted by the lanthanum hexaboride filament assembly passes sequentially through the magnetic deflection unit, the quadrupole focusing unit, and the monopolar focusing unit to reach the transmission target. The vacuum system is connected to the cathode system, the magnetic deflection system, the magnetic focusing system, and the anode system.

2. The X-ray generating apparatus according to claim 1, characterized in that: The high-voltage connection assembly includes a high-voltage cable connector, a ceramic socket, and a sealing structure. The high-voltage cable connector is sealed to one end of the cathode cavity. The high-voltage cable connector is provided with a grid high-voltage wire and a filament high-voltage wire. One end of the ceramic socket is connected to the cathode high-voltage assembly, and the other end is connected to the high-voltage cable connector through the sealing structure. The sealing structure is filled with insulating oil.

3. The X-ray generating apparatus according to claim 2, characterized in that: The cathode high voltage assembly further includes a gate assembly, a gate post, and a filament insert. The gate assembly includes a gate hole. The gate post, the filament insert, and the lanthanum hexaboride filament assembly are all located between the gate assembly and the ceramic socket. The gate post and the filament insert are respectively connected to the ceramic socket. The lanthanum hexaboride filament assembly is connected to the filament high voltage line through the filament insert. The gate assembly is connected to the gate high voltage line through the gate post.

4. The X-ray generating apparatus according to claim 1, characterized in that: The cathode system further includes an anode plate located at the upper end of the cathode cavity. The magnetic deflection unit is located above the cathode system and connected to the anode plate. The magnetic deflection unit includes a deflection lens and a deflection lens housing that encloses the deflection lens. The deflection lens includes two sets of coils respectively disposed in a first direction and a second direction. The first direction is perpendicular to the second direction, and the plane containing the first direction and the second direction is perpendicular to the motion path of the electron beam.

5. The X-ray generating apparatus according to claim 4, characterized in that: The quadrupole focusing unit includes a quadrupole focusing lens and a quadrupole focusing lens housing that encloses the quadrupole focusing lens. The quadrupole focusing lens includes two sets of coils respectively disposed in a third direction and a fourth direction. The third direction is perpendicular to the fourth direction, and the plane containing the third direction and the fourth direction is perpendicular to the movement path of the electron beam.

6. The X-ray generating apparatus according to claim 5, characterized in that: The monopolar focusing unit is connected to the housing of the quadrupole focusing lens. The monopolar focusing unit includes a monopolar focusing lens, a pole shoe structure, and a pole shoe cover. The pole shoe cover is located above the pole shoe structure and connected to the pole shoe structure. The pole shoe structure and the pole shoe cover are closed to form a cavity, and the monopolar focusing lens is located in the cavity.

7. The X-ray generating apparatus according to claim 6, characterized in that: A vacuum chamber is provided between the magnetic deflection system and the magnetic focusing system. One end of the vacuum chamber is connected to the housing of the quadrupole focusing lens, and the other end is connected to the pole shoe cover. The vacuum system includes an ion pump, a getter pump, and a vacuum valve. The ion pump and the vacuum valve are both located on the outer wall of the cathode cavity and communicate with the cathode cavity. The getter pump is located in the vacuum cavity.

8. The X-ray generating apparatus according to claim 7, characterized in that: The anode target assembly also includes a target cooling cover and a limiting aperture. The target cooling cover is provided with cooling water channels, and the transmission target is provided with a reserved rotation hole. The limiting aperture includes an aperture opening. The transmission target is located between the target cooling cover and the limiting aperture. The transmission target is connected to the limiting aperture through a sealing ring. The electron beam emitted by the lanthanum hexaboride filament assembly passes through the limiting aperture and reaches the transmission target through the aperture opening.

9. The X-ray generating apparatus according to claim 8, characterized in that: The anode system also includes a non-magnetic titanium tube, which is inserted into the cavity formed by the pole shoe structure and the closed pole shoe cover through the top opening of the pole shoe cover. The limiting aperture is located in the channel of the non-magnetic titanium tube.

10. The X-ray generating apparatus according to claim 7, characterized in that: The connection between the cathode system and the magnetic deflection system includes indium cold pressing welding; the connection between the magnetic focusing system and the pole shoe structure includes indium cold pressing welding; and the connection between the pole shoe structure and the pole shoe cover includes indium cold pressing welding.

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