Magnetic field device and method for regulating and controlling glow discharge mass spectrum deep sputtering

Abstract

The invention discloses a magnetic field device and method for regulating and controlling glow discharge mass spectrometry deep sputtering, and the device comprises a housing which is of a hollow structure; the cover body covers the opening of the shell in an adaptive manner, and a limiting part is arranged on one side, far away from the shell, of the cover body; the insulating plate is adaptively arranged in the shell, a first through hole and six second through holes are formed in the insulating plate in the height direction, the six second through holes uniformly surround the periphery of the first through hole, a first spherical magnet is adaptively arranged in the first through hole, and a second spherical magnet is adaptively arranged in each second through hole; the magnetic pole directions of the six second spherical magnets are the same and are all parallel to the insulating plate in the height direction, and the magnetic pole direction of the first spherical magnet is opposite to the magnetic pole direction of the second spherical magnets. According to the invention, the problem of uneven shape of the sputtering pit can be effectively improved, and the depth resolution is improved on the basis of improving the signal strength.

Description

Technical Field

[0001] The invention relates to the technical field of inorganic mass spectrometry analysis, and further to a magnetic field device and method for regulating deep sputtering of glow discharge mass spectrometry. Background Art

[0002] In recent years, the rapid development of advanced materials has put forward higher and higher requirements for material characterization technology and methods. For the composition of materials, the concentration and depth distribution of trace or trace elements have a great influence on the performance of materials, such as optical, electrical, acoustic, and mechanical properties. The development of efficient characterization devices and methods to achieve accurate characterization of the concentration and depth distribution of trace or trace elements not only helps to reveal the performance, preparation process and mechanism of materials, but is also crucial to optimize the performance of materials and design and prepare higher performance materials.

[0003] Glow discharge mass spectrometry has the advantages of direct analysis of solid materials, low resolution, detection limit, wide linear dynamic range, one-time analysis of major, minor and trace elements, and small matrix effect. It has become an indispensable and important characterization and research method in the field of material research and production. In the process of in-depth analysis of materials, glow discharge mass spectrometry can provide concentration and depth distribution information of major, minor and trace elements from the surface to the inside, providing an effective means to reveal the diffusion and segregation processes of elements and performance prediction.

[0004] During the depth analysis of glow discharge mass spectrometry, the sputtering pits generated on the sample surface generally have a morphological feature of deep edges and shallow middles, that is, there are different degrees of unevenness at the bottom of the sputtering pits. The nature of the uneven sputtering affects the resolution and accuracy of the depth analysis of glow discharge mass spectrometry.

[0005] Therefore, it is necessary to design a magnetic field device and method for regulating deep sputtering of glow discharge mass spectrometry to solve the above problems. Summary of the invention

[0006] In view of the above technical problems, the purpose of the present invention is to provide a magnetic field device and method for regulating deep sputtering of glow discharge mass spectrometry, which can effectively improve the problem of uneven sputtering crater shape and improve the depth resolution on the basis of improving signal intensity.

[0007] In order to achieve the above object, the present invention provides a magnetic field device for regulating glow discharge mass spectrometry deep sputtering, comprising:

[0008] A shell, wherein the shell is conductive and is a hollow structure with an opening at one end;

[0009] A cover body, the cover body is conductive, the cover body is adapted to cover the opening of the shell, a limiting portion is provided on a side of the cover body away from the shell, and the limiting portion is used to limit the sample;

[0010] an insulating plate adapted to be installed in the housing, the insulating plate being provided with a first through hole and six second through holes along the height direction, the six second through holes being evenly arranged around the first through hole, a first spherical magnet being adapted to be installed in the first through hole, the diameter of the first spherical magnet being smaller than the depth of the first through hole, and a second spherical magnet being adapted to be installed in each of the second through holes, the diameter of the second spherical magnet being smaller than the depth of the second through hole;

[0011] The magnetic pole directions of the six second spherical magnets are the same and are all parallel to the insulating plate in the height direction. The magnetic pole direction of the first spherical magnet is opposite to the magnetic pole direction of the second spherical magnet.

[0012] In some embodiments, the shell and the cover are both made of copper material, and the shell and the insulating plate are both cylindrical structures.

[0013] In some embodiments, the limiting portion includes a plurality of bosses, and the plurality of bosses surround and form a receiving space adapted to the outer contour of the sample, and the sample is adapted to be installed in the receiving space so that the plurality of bosses limit the sample.

[0014] In some embodiments, four bosses are provided, and all of the four bosses are square structures. The four bosses are arranged to form a square accommodating space, and the four bosses are equidistant from the center of the top of the cover body.

[0015] In some embodiments, the insulating plate is a polytetrafluoroethylene plate, and the diameter of the first through hole is smaller than the diameter of the first spherical magnet, so that the first spherical magnet and the first through hole have an interference fit;

[0016] The diameter of the second through hole is smaller than the diameter of the second spherical magnet, so that the second spherical magnet is interference-fitted with the second through hole.

[0017] In some embodiments, the insulating plate can be detachably installed in the shell, and a plurality of the insulating plates are provided, and the distances between two adjacent second through holes on the plurality of insulating plates are different, so that when the second spherical magnets are installed on different insulating plates, the distances between the second spherical magnets are different.

[0018] In some embodiments, the first spherical magnet and the second spherical magnet are both sintered NdFeB spherical magnets, the six second spherical magnets are of the same model, and the first spherical magnet and the second spherical magnet are of the same or different models.

[0019] In some embodiments, it further comprises:

[0020] A first shell, wherein the first shell is conductive, is a hollow structure, and has an opening at one end, and a tantalum sheet, a first insulating ceramic sheet, and a second insulating ceramic sheet are sequentially arranged in the first shell;

[0021] A second shell, the second shell is made of insulating material, one end of the second shell is inserted into the first shell and is threadedly connected to the first shell, so that the second shell clamps and fixes the tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet between the bottom of the first shell and the end of the second shell;

[0022] A third shell, the third shell is made of insulating material, the third shell is detachably connected to the end of the second shell away from the first shell, an elastic member is arranged inside the third shell, and the end of the third shell away from the second shell is connected to an injection rod;

[0023] The sample, the cover, the insulating plate and the shell are assembled into one and installed in the second shell. The overall structure is supported on the second insulating ceramic sheet by the elastic member, wherein the sample is located on a side close to the second insulating ceramic sheet and the shell is located on a side close to the elastic member.

[0024] According to another aspect of the present invention, the present invention further provides a method for using the magnetic field device for regulating glow discharge mass spectrometry deep sputtering as described in any one of the above, comprising the steps of:

[0025] Installing a first spherical magnet in the first through hole, and installing six second spherical magnets in the corresponding second through holes, wherein the magnetic poles of the six second spherical magnets have the same direction and are parallel to the insulating plate in the height direction, and the magnetic pole direction of the first spherical magnet is opposite to the magnetic pole direction of the second spherical magnet;

[0026] Putting the insulating plate fixed with the first spherical magnet and the second spherical magnet into the shell, and then fitting the cover body to the opening of the shell;

[0027] The sample is placed in the middle position of the cover body on the side away from the shell, so that the limiting part limits the sample, thereby preventing the sample from being displaced during the filling, injection and analysis processes.

[0028] In some embodiments, the steps are further included:

[0029] The tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet are sequentially placed in the first shell, one end of the second shell is inserted into the first shell and is threadedly connected to the first shell, so that the second shell clamps and fixes the tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet between the bottom of the first shell and the end of the second shell;

[0030] The assembled shell is placed in the second shell, and the third shell is threadedly connected to the end of the second shell away from the first shell, so that the whole structure is supported on the second insulating ceramic sheet by the elastic member, wherein the sample is located on the side close to the second insulating ceramic sheet, and the shell is located on the side close to the elastic member;

[0031] The injection rod is threadably connected to the third shell, and the whole structure assembled from the first shell, the second shell and the third shell is pushed into the glow discharge mass spectrometer cell through the injection rod.

[0032] Compared with the prior art, the magnetic field device and method for regulating deep sputtering of glow discharge mass spectrometry provided by the present invention have the following beneficial effects:

[0033] In the present invention, by arranging a limiting portion on the cover body, the sample can be effectively restricted to the center position of the cover body, thereby avoiding the uneven sputtering caused by sample displacement during the sample preparation process; by adopting insulating plates with different through-hole spacings, the distance between the second spherical magnets is indirectly adjusted, that is, different spacings can be selected in combination with the discharge aperture; the horizontal component of the magnetic flux density is concentrated in the central area, and part of the electrons can be bound in the area, the electron motion trajectory in the area is bent, and the collision frequency with neutral particles, especially argon atoms, is increased, which promotes more argon atoms to be ionized and increases the number density of argon ions. The increase in the number density of argon ions can increase the sputtering flux in the area; the sputtering flux obtained by magnetic field enhancement is used to balance the local high sputtering flux caused by the electric field effect at the edge of the sample, so as to achieve layer-by-layer sputtering and obtain a sputtering pit with a flat bottom, thereby obtaining excellent signal strength and depth resolution. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The preferred implementation modes will be described below in a clear and understandable manner with reference to the accompanying drawings to further illustrate the above-mentioned characteristics, technical features, advantages and implementation methods of the present invention.

[0035] Figure 1 It is a schematic structural diagram of a magnetic field device for regulating deep sputtering of glow discharge mass spectrometry according to a preferred embodiment of the present invention;

[0036] Figure 2is a structural schematic diagram of a cover body of a preferred embodiment of the present invention;

[0037] Figure 3 is a schematic structural diagram of an insulating plate according to a preferred embodiment of the present invention;

[0038] Figure 4 This is a sputtering pit morphology image obtained when analyzing an aluminum sheet by glow discharge mass spectrometry without magnetic field regulation in a preferred embodiment of the present invention;

[0039] Figure 5 This is a sputtering pit morphology diagram obtained when analyzing an aluminum sheet by glow discharge mass spectrometry under magnetic field control in a preferred embodiment of the present invention;

[0040] Figure 6 It is the signal intensity of aluminum element obtained in the comparative example and the embodiment of the preferred embodiment of the present invention.

[0041] Description of Figure Numbers:

[0042] Shell 1, cover 2, insulating plate 3, first spherical magnet 4, second spherical magnet 5, boss 6, sample 7, first shell 8, tantalum sheet 9, first insulating ceramic sheet 10, second insulating ceramic sheet 11, second shell 12, third shell 13, elastic member 14, injection rod 15. DETAILED DESCRIPTION

[0043] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the specific implementation methods of the present invention will be described below with reference to the accompanying drawings. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings and other implementation methods can be obtained based on these drawings without creative work.

[0044] In order to simplify the drawings, only the parts related to the invention are schematically shown in each figure, and they do not represent the actual structure of the product. In addition, in order to simplify the drawings and facilitate understanding, in some figures, only one of the parts with the same structure or function is schematically drawn or marked. In this article, "one" not only means "only one", but also means "more than one".

[0045] It should be further understood that the term “and / or” used in the specification and appended claims refers to any combination and all possible combinations of one or more of the associated listed items, and includes these combinations.

[0046] In this document, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0047] In addition, in the description of the present application, the terms "first", "second", etc. are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0048] In one embodiment, the reference specification Figures 1 to 3 The present invention provides a magnetic field device for regulating deep sputtering of glow discharge mass spectrometry, comprising: a shell 1, a cover 2 and an insulating plate 3. The shell 1 is conductive, and the shell 1 is a hollow structure with an opening at one end; the cover 2 is conductive, and the cover 2 is adapted to cover the opening of the shell 1, and a limiting portion is provided on the side of the cover 2 away from the shell 1, and the limiting portion is used to limit the sample 7. The insulating plate 3 is adapted to be installed in the shell 1, and the insulating plate 3 is provided with a first through hole and six second through holes along the height direction, and the six second through holes are evenly surrounded by the first through hole, and a first spherical magnet 4 is adapted to be installed in the first through hole, and the diameter of the first spherical magnet 4 is smaller than the depth of the first through hole, and a second spherical magnet 5 is adapted to be installed in each second through hole, and the diameter of the second spherical magnet 5 is smaller than the depth of the second through hole. The magnetic poles of the six second spherical magnets 5 are in the same direction and are parallel to the insulating plate 3 in the height direction. The magnetic poles of the first spherical magnet 4 are opposite to the magnetic poles of the second spherical magnet 5. By adopting the annular magnet array, the performance of the glow discharge mass spectrometer for material analysis is improved. The structure is simple and reasonable, and the sputtering crater morphology can be effectively controlled while the signal strength is enhanced. The method is suitable for glow discharge mass spectrometers or similar devices.

[0049] Specifically, refer to the attached manual Figure 1 The shell 1 and the cover 2 are made of metal or alloy materials, preferably copper materials. The shell 1 and the insulating plate 3 are cylindrical structures, square structures, etc., preferably cylindrical structures. The opening of the shell 1 is located at the left end of the shell, and the shell 1 and the cover 2 are connected by snaps or threads. The specific dimensions of the shell 1 and the cover 2 can be set according to actual needs. For example, the thickness of the shell 1 is 1.00mm, the outer diameter is 35.00mm, and the height is 7.00mm; the thickness of the cover 2 is 1.00mm, the outer diameter is 35.00mm, and the height is 3.00mm.

[0050] The insulating plate 3 is a polytetrafluoroethylene plate, and the height direction of the insulating plate 3 is Figure 1The left and right direction in the figure is the thickness direction of the insulating plate 3. If the insulating plate 3 is a cylinder, the center of the first through hole coincides with the center of the cylinder, and the six second through holes are evenly surrounded by the first through hole, that is, the centers of the six second through holes are distributed on the six vertices of a regular hexagon centered on the first through hole. For example: the height of the insulating plate 3 is 5.00mm and the diameter is 30.50mm. The diameters of the first through hole and the second through hole are both 4.70mm, and the distances between the centers of two adjacent second through holes are 5.20mm, 5.70mm, 6.20mm and 6.70mm, respectively, and may also be other reasonable sizes, such as 5.30mm, 5.40mm, 5.50mm, 5.60mm, 5.80mm, 5.90mm, etc.

[0051] The first spherical magnet 4 and the second spherical magnet 5 are both sintered NdFeB spherical magnets, and their models can be sintered NdFeB N35, N42, N45 and other types. The six second spherical magnets 5 are of the same model, and the first spherical magnet 4 and the second spherical magnet 5 are of the same or different models.

[0052] Furthermore, the diameter of the first through hole is smaller than the diameter of the first spherical magnet 4, so that the first spherical magnet 4 is interference-fitted with the first through hole; the diameter of the second through hole is smaller than the diameter of the second spherical magnet 5, so that the second spherical magnet 5 is interference-fitted with the second through hole. The diameter of the spherical magnet is slightly larger than the corresponding through hole diameter. If the through hole diameter is 4.70 mm, the diameter of the spherical magnet can be set to 4.76 mm. Since the polytetrafluoroethylene plate has a certain elasticity, the spherical magnet is installed in the corresponding through hole by interference fit, which has the advantage of simple loading and unloading.

[0053] The limiting part includes a plurality of bosses 6, which surround and form a receiving space adapted to the outer contour of the sample. The sample 7 is adapted to be installed in the receiving space, so that the plurality of bosses 6 limit the sample 7. For example, there are four bosses 6, and the four bosses 6 are all square structures. The bottoms of the four bosses 6 are fixed on the cover body 2 to form a square receiving space. The four bosses 6 are located on the side of the cover body 2 away from the shell 1, and the four bosses 6 are at the same distance from the center of the top of the cover body 2. For example: the distance between the four bosses 6 and the center of the top of the cover body 2 is 11.00mm, the size of the four bosses 6 is 1.00mm×1.00mm×0.50mm, and the bottom surface of the sample 7 is a square, with a size of 20.00×20.00mm, and a height of not less than 0.50mm.

[0054] The insulating plate 3 is detachably installed in the housing 1 . There are multiple insulating plates 3 . The distances between two adjacent second through holes on the multiple insulating plates 3 are different, so that when the second spherical magnets 5 are installed on different insulating plates 3 , the distances between the second spherical magnets 5 are different.

[0055] In this embodiment, the magnetic field design is used to enhance the sputtering in the central area of ​​the sputtering pit of the glow discharge mass spectrometry depth analysis, and the sputtering unevenness caused by the edge electric field effect is corrected. The magnetic field control device includes a shell 1, a cover 2, an insulating plate 3, and a spherical magnet array. The top of the cover 2 has four copper small rectangular parallelepiped bosses 6 distributed at equal distances from the center of the circle, and the cylindrical polytetrafluoroethylene insulating plate 3 has seven through holes that are centrally symmetrical. Seven sintered NdFeB spherical magnets are fixed in the holes, and the magnetic pole direction is perpendicular to the height direction of the through hole. The magnetic pole direction of the central magnet is opposite to that of the surrounding magnets, and the distance between the centers of the through holes can be set to 5.20 mm, 5.70 mm, 6.20 mm, and 6.70 mm. The combination of the shell 1, the cover 2, the insulating plate 3, and the spherical magnet array can achieve the purpose of regulating sputtering and optimizing the shape of the sputtering pit, and ultimately improve the depth resolution and accuracy of the glow discharge depth analysis.

[0056] In one embodiment, the reference specification Figure 1 , a magnetic field device for regulating deep sputtering of glow discharge mass spectrometry provided by the present invention also includes: a first shell 8, a second shell 12 and a third shell 13, the first shell 8 is conductive, the first shell 8 is a hollow structure, one end of which has an opening, and a tantalum sheet 9, a first insulating ceramic sheet 10 and a second insulating ceramic sheet 11 are sequentially arranged in the first shell 8. The first insulating ceramic sheet 10 and the second insulating ceramic sheet 11 both have holes, and the aperture of the first insulating ceramic sheet 10 is larger than the aperture of the second insulating ceramic sheet 11. The second shell 12 is made of insulating material, one end of the second shell 12 is inserted into the first shell 8, and is threadedly connected to the first shell 8, so that the second shell 12 clamps and fixes the tantalum sheet 9, the first insulating ceramic sheet 10 and the second insulating ceramic sheet 11 between the shell bottom of the first shell 8 and the end of the second shell 12. The third housing 13 is made of insulating material. The third housing 13 is detachably connected to the end of the second housing 12 away from the first housing 8. An elastic member 14 is provided in the third housing 13. The elastic member 14 can be a metal spring. The end of the third housing 13 away from the second housing 12 is connected to an injection rod 15. The injection rod 15 and the third housing 13 can be fixedly connected by threads. The sample 7, the cover 2, the insulating plate 3, and the shell 1 are assembled into one and installed in the second housing 12. The whole structure is supported on the second insulating ceramic sheet 11 by the elastic member 14, wherein the sample 7 is located on the side close to the second insulating ceramic sheet 11, and the shell 1 is located on the side close to the elastic member 14. The entire device is pushed into the glow discharge mass spectrometer cell by the injection rod 15, and the sample filling is completed.

[0057] The deep sputtering of the glow discharge mass spectrometer is regulated by using a device with a specific spherical magnet array. The plasma density is locally increased by applying a magnetic field with a specific spatial distribution to the ion source of the glow discharge mass spectrometer, thereby achieving sputtering enhancement in the local area. In addition, the structural parameters of the device are changed to adapt to different discharge conditions and analysis samples, and a relatively flat sputtering pit is obtained, that is, the effect of layer-by-layer sputtering peeling, ultimately achieving the purpose of improving the depth resolution and accuracy of the deep analysis of the glow discharge mass spectrometer.

[0058] By adding an additional small rectangular boss 6 on the top of the cover 2, the sample 7 can be effectively fixed at the center of the cover 2, avoiding the uneven sputtering caused by sample displacement during sample preparation; by using different through-hole spacings, the distance between the spherical magnets is indirectly adjusted, that is, different spacings can be selected in combination with the discharge aperture, such as 7.5mm, 10.0mm, 12.5mm, 15mm, etc.; the horizontal component of the magnetic flux density is concentrated in the central area, which can bind some electrons in this area, and the electron motion trajectory in this area is bent, and the collision frequency with neutral particles, especially argon atoms, is increased, which promotes more argon atoms to be ionized, and increases the number density of argon ions. The increase in the number density of argon ions can increase the sputtering flux in this area. The sputtering flux obtained by magnetic field enhancement balances the local high sputtering flux caused by the electric field effect at the edge of the sample, realizes layer-by-layer sputtering and obtains a sputtering pit with a flat bottom, thereby obtaining excellent signal strength and depth resolution.

[0059] It should be noted that the control effect of the above-mentioned control device on the sputtering pit morphology is related to the glow discharge mass spectrometry discharge parameters, especially the pressure of argon gas, that is, the number density of argon atoms. Therefore, the control effect of a specific spherical magnet array control device on sputtering is only more obvious within a certain range of argon gas pressure. Therefore, the present invention designs different through-hole spacings and does not limit the model and size of the spherical magnet used.

[0060] According to another aspect of the present invention, Figures 1 to 3 The present invention further provides a method for using the magnetic field device for regulating glow discharge mass spectrometry deep sputtering as described in any one of the above, comprising the steps of:

[0061] The first spherical magnet 4 is installed in the first through hole, and the six second spherical magnets 5 are installed in the corresponding second through holes, wherein the magnetic poles of the six second spherical magnets 5 have the same direction and are all parallel to the insulating plate 3 in the height direction, and the magnetic pole direction of the first spherical magnet 4 is opposite to the magnetic pole direction of the second spherical magnet 5. For example: the N pole of the first spherical magnet 4 is facing upward, and the magnetic poles of the six surrounding second spherical magnets 5 are facing upward; or the S pole of the first spherical magnet 4 is facing upward, and the N poles of the six surrounding second spherical magnets 5 are facing upward, such as Figure 2As shown, a ring-shaped permanent magnet array is formed according to the above method.

[0062] The insulating plate 3 fixed with the first spherical magnet 4 and the second spherical magnet 5 is placed in the housing 1, and the cover 2 is fitted and covered on the opening of the housing 1. The cylindrical polytetrafluoroethylene insulating plate 3 fixed with the annular permanent magnet array is placed in the hollow cylindrical copper housing 1. The cylindrical polytetrafluoroethylene insulating plate 3 is wrapped with the copper cover 2, and the outer cylindrical copper housing 1 and the copper cover 2 play the role of container and conductor.

[0063] The sample 7 is placed in the middle of the side of the cover 2 away from the housing 1, so that the limiting part limits the sample 7, thereby preventing the sample 7 from being displaced during the filling, injection and analysis process. By placing the sample 7 on the top of the cover 2, the sample 7 is fixed to the central area of ​​the upper surface of the cover 2 by four small rectangular bosses 6, ensuring that the sample will not be displaced during the filling, injection and analysis process, and at the same time, it can always be in a specific area with a specific spatial distribution magnetic field, such as Figure 3 As shown, at this time, the height between the upper surface of the sample 7 and the spherical magnet array is 2.00 mm, which is the sum of the thickness of the cover 2 and the thickness of the sample 7. The annular permanent magnet array control device is built and then needs to be fixed to the sample injection device.

[0064] Furthermore, the method further comprises the steps of:

[0065] The tantalum sheet 9, the first insulating ceramic sheet 10 and the second insulating ceramic sheet 11 are sequentially placed in the first housing 8, one end of the second housing 12 is inserted into the first housing 8 and is threadedly connected to the first housing 8, so that the second housing 12 clamps and fixes the tantalum sheet 9, the first insulating ceramic sheet 10 and the second insulating ceramic sheet 11 between the bottom of the first housing 8 and the end of the second housing 12;

[0066] The assembled housing 1 is placed in the second housing 12, and the third housing 13 is threadedly connected to the end of the second housing 12 away from the first housing 8, so that the whole structure is supported on the second insulating ceramic sheet 11 through the elastic member 14, wherein the sample 7 is located on the side close to the second insulating ceramic sheet 11, and the housing 1 is located on the side close to the elastic member 14;

[0067] The injection rod 15 is threadedly connected to the third housing 13 , and the whole structure assembled by the first housing 8 , the second housing 12 , and the third housing 13 is pushed into the glow discharge mass spectrometer cell through the injection rod 15 .

[0068] In this embodiment, an external voltage is applied to the injection rod 15, and the elastic member 14, the housing 1 of the annular permanent magnet array control device, and the sample 7 are all made of conductive metal, and the surface of the sample 7 is charged. The injection rod 15 is connected to the negative electrode of the high-voltage power supply, and the sample 7 serves as the cathode part of the glow discharge. The sample 7 serves as the cathode, and the first metal shell 8 and the discharge battery are grounded as the anode. The circular openings of the tantalum sheet 9, the first insulating ceramic sheet 10, and the second insulating ceramic sheet 11 determine that the portion of the sample 7 exposed to the plasma is a circular area, and the size of the circular area is determined by the diameter of the circular openings of the tantalum sheet 9 and the second insulating ceramic sheet 11. The annular permanent magnet array will excite a magnetic field with a specific spatial distribution on the surface of the sample 7, and the magnetic field presents a centrally symmetrical distribution. Considering the transverse magnetic field, that is, the magnetic field component perpendicular to the electric field direction, the distribution characteristics of the transverse magnetic field of the designed annular permanent magnet array are as follows: the intensity is relatively small in a very small range in the center, which is 10.0mT~20.0mT, while in the annular area of ​​about 5.00mm on the periphery, the intensity of the transverse magnetic field can reach about 80.0mT, and then there will be a weak magnetic field area with a width of about 2.00mm~3.00mm, and the magnetic field strength is about 10.0mT~40.0mT.

[0069] Example

[0070] A permanent magnet magnetic field control device was formed using a sintered NdFeB N35 spherical magnet according to the above description. The argon pressure was 4.7 mPa, the discharge voltage was 1.8 kV, the discharge current was 1.0 mA, the opening diameter of the tantalum sheet 9 and the second insulating ceramic sheet 11 was 15.00 mm, that is, the sputtering aperture was 15.00 mm, the sample 7 was an aluminum sheet, and the duration of the glow discharge mass spectrometry depth analysis was 25 min.

[0071] Comparative Example

[0072] The only difference compared to the embodiment is that the annular magnetic bead array is not applied.

[0073] The sputtering pits left on the sample surface after sputtering in the embodiment and the comparative example were detected by profilometer. The detection results are as follows: Figure 4 , Figure 5 shown. Figure 4 and Figure 5 The sputtering pit morphologies obtained after in-depth analysis of the comparative example and the embodiment are shown respectively. The designed annular magnetic bead array control device can improve the sputtering morphology to a certain extent and make the bottom of the sputtering pit flatter. In addition, it is worth noting that Figure 4 The depth of the sputtering pit shown is about 2.5 μm. When the designed permanent magnet array control device is not used, the edge sputtering intensity is greater than the center sputtering intensity. After applying the designed permanent magnet array magnetic field control device, Figure 5The depth of the sputtering pit shown reaches about 3.5 μm, and the difference between the sputtering depth in the center area and the sputtering depth in the edge area is narrowed. According to existing research and technology, the increase in sputtering depth will aggravate the non-uniformity of sputtering, resulting in an uneven bottom of the sputtering pit.

[0074] The unevenness of the sputtering crater for GDS depth analysis is defined as δ:

[0075]

[0076] Among them, Hmax and Hmin represent the distance from the lowest and highest points of the sputtering pit to the top of the sputtering pit, respectively. The greater the height difference (Hmax-Hmin) at the bottom of the sputtering pit, the more uneven the sputtering pit is; when the height difference is the same, the smaller the average depth of the sputtering pit 0.5×(Hmax+Hmin), the more uneven the sputtering pit is.

[0077] By comparing the embodiment and the comparative example, it is calculated that the unevenness of the sputtering pits of the two are 0.092 and 0.184 respectively, indicating that the shape of the sputtering pit is improved after using the annular magnetic bead array control device designed by the present invention, which is beneficial to improving the accuracy of depth analysis.

[0078] like Figure 6 As shown, by comparing the signal strength of the embodiment and the comparative example (without using the magnetic field control device), the signal strength of the major element aluminum is 1.25×10-11A and 7.73×10-12A respectively, and the signal strength of the major element is increased by nearly 1.6 times. The designed permanent magnet array magnetic field control device can enhance the element signal strength.

[0079] The annular magnetic bead array magnetic field control device involved in the patent of this invention is based on the basic principle of magnetic field enhanced sputtering. By designing a permanent magnet array with a specific spatial magnetic field distribution, the shape of the sputtering pit is improved, and the signal intensity is enhanced. It is suitable for glow discharge mass spectrometers or similar instruments.

[0080] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described or recorded in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0081] It should be noted that the above embodiments can be freely combined as needed. The above are only preferred embodiments of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be regarded as the protection scope of the present invention.

Claims

1. A magnetic field device for regulating deep sputtering of glow discharge mass spectrometry, characterized in that: include: A shell, wherein the shell is conductive and is a hollow structure with an opening at one end; A cover body, the cover body is conductive, the cover body is adapted to cover the opening of the shell, a limiting portion is provided on a side of the cover body away from the shell, and the limiting portion is used to limit the sample; an insulating plate adapted to be installed in the housing, the insulating plate being provided with a first through hole and six second through holes along the height direction, the six second through holes being evenly arranged around the first through hole, a first spherical magnet being adapted to be installed in the first through hole, the diameter of the first spherical magnet being smaller than the depth of the first through hole, and a second spherical magnet being adapted to be installed in each of the second through holes, the diameter of the second spherical magnet being smaller than the depth of the second through hole; The magnetic pole directions of the six second spherical magnets are the same and are all parallel to the insulating plate in the height direction. The magnetic pole direction of the first spherical magnet is opposite to the magnetic pole direction of the second spherical magnet.

2. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 1, characterized in that: The shell and the cover are both made of copper material, and the shell and the insulating plate are both cylindrical structures.

3. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 2, characterized in that: The limiting portion includes a plurality of bosses, and the plurality of bosses surround and form a containing space adapted to the outer contour of the sample. The sample is adapted to be installed in the containing space, so that the plurality of bosses limit the sample.

4. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 3, characterized in that: There are four bosses, all of which are square structures. The four bosses are arranged to form a square accommodating space, and the distances between the four bosses and the center of the top of the cover body are equal.

5. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 2, characterized in that: The insulating plate is a polytetrafluoroethylene plate, and the diameter of the first through hole is smaller than the diameter of the first spherical magnet, so that the first spherical magnet and the first through hole are interference fit; The diameter of the second through hole is smaller than the diameter of the second spherical magnet, so that the second spherical magnet is interference-fitted with the second through hole.

6. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 5, characterized in that: The insulating plate is detachably installed in the shell, and a plurality of insulating plates are provided. The distances between two adjacent second through holes on the plurality of insulating plates are different, so that when the second spherical magnets are installed on different insulating plates, the distances between the second spherical magnets are different.

7. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to claim 5, characterized in that: The first spherical magnet and the second spherical magnet are both sintered NdFeB spherical magnets, the six second spherical magnets are of the same model, and the first spherical magnet and the second spherical magnet are of the same or different models.

8. The magnetic field device for regulating glow discharge mass spectrometry deep sputtering according to any one of claims 1 to 7, characterized in that: Also includes: A first shell, wherein the first shell is conductive, is a hollow structure, and has an opening at one end, and a tantalum sheet, a first insulating ceramic sheet, and a second insulating ceramic sheet are sequentially arranged in the first shell; A second shell, the second shell is made of insulating material, one end of the second shell is inserted into the first shell and is threadedly connected to the first shell, so that the second shell clamps and fixes the tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet between the bottom of the first shell and the end of the second shell; A third shell, the third shell is made of insulating material, the third shell is detachably connected to the end of the second shell away from the first shell, an elastic member is arranged inside the third shell, and the end of the third shell away from the second shell is connected to an injection rod; The sample, the cover, the insulating plate and the shell are assembled into one and installed in the second shell. The overall structure is supported on the second insulating ceramic sheet by the elastic member, wherein the sample is located on a side close to the second insulating ceramic sheet and the shell is located on a side close to the elastic member.

9. A method for using the magnetic field device for regulating glow discharge mass spectrometry deep sputtering as claimed in any one of claims 1 to 8, characterized in that: Includes steps: Installing a first spherical magnet in the first through hole, and installing six second spherical magnets in the corresponding second through holes, wherein the magnetic poles of the six second spherical magnets have the same direction and are parallel to the insulating plate in the height direction, and the magnetic pole direction of the first spherical magnet is opposite to the magnetic pole direction of the second spherical magnet; Putting the insulating plate fixed with the first spherical magnet and the second spherical magnet into the shell, and then fitting the cover body to the opening of the shell; The sample is placed in the middle position of the cover body on the side away from the shell, so that the limiting part limits the sample, thereby preventing the sample from being displaced during the filling, injection and analysis processes.

10. The method according to claim 9, characterized in that Also includes the steps: The tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet are sequentially placed in the first shell, one end of the second shell is inserted into the first shell and is threadedly connected to the first shell, so that the second shell clamps and fixes the tantalum sheet, the first insulating ceramic sheet and the second insulating ceramic sheet between the bottom of the first shell and the end of the second shell; The assembled shell is placed in the second shell, and the third shell is threadedly connected to the end of the second shell away from the first shell, so that the whole structure is supported on the second insulating ceramic sheet by the elastic member, wherein the sample is located on the side close to the second insulating ceramic sheet, and the shell is located on the side close to the elastic member; The injection rod is threadably connected to the third shell, and the whole structure assembled from the first shell, the second shell and the third shell is pushed into the glow discharge mass spectrometer cell through the injection rod.

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