A new type of anode layer ion source

Abstract

The present invention discloses a novel anode layer ion source. The anode layer ion source prevents positive ions in the ion channel from bombarding the cathode surface by arranging outer shielding covers on the surfaces of the inner cathode and the outer cathode, thereby reducing metal atoms generated by sputtering, effectively suppressing cathode etching, and preventing sample contamination. At the same time, a magnetic shielding cover is arranged around the inner contours of the inner cathode and the outer cathode inside the ion source to shield the magnetic field near the anode, optimize the electromagnetic field distribution, reduce internal discharge, improve the stability of the process, and thus increase the working life of the anode layer ion source.

Description

Technical Field

[0001] The invention relates to the field of physical vapor deposition, and in particular to a novel anode layer ion source. Background Art

[0002] Anodic layer ion sources offer the advantages of a simple structure, high ion beam current density, and good ion energy controllability. They are widely used in the PVD field for important functions such as sample cleaning, ion etching, ion implantation, and ion beam-assisted deposition. Currently, anodic layer ion sources are being developed towards higher discharge power to achieve a larger ion beam current and thus improve coating quality. However, this increase in discharge power not only brings serious cathode etching problems, leading to sample contamination, but also may cause "sparking" between the anode and cathode, resulting in process instability.

[0003] Among existing designs, the most common method to reduce cathode etching is to optimize the magnetic field distribution of the ion source, that is, to control the ions by changing the magnetic mirror ratio and magnetic field strength to constrain electrons. However, since the ions are always attracted by the cathode, the optimization effect of this solution is limited. Another common method is to press materials with low sputtering yields, such as graphite, into the cathode surface to reduce the cathode atoms introduced by sputtering. However, the bonding strength between graphite and cathode materials is poor, and the conductivity is different, resulting in poor process stability, especially under high-voltage discharge conditions. To address the discharge phenomenon between the cathode and anode of the ion source, a common method is to add a shielding cover with a suspended potential between the cathode and anode. However, this solution has no effect on the magnetic field. There is still a cross-electromagnetic field between the cathode and anode, which cannot completely eliminate the internal discharge of the ion source.

[0004] Therefore, the existing technology still needs to be improved and developed. Summary of the Invention

[0005] In view of the above-mentioned deficiencies in the prior art, the purpose of the present invention is to provide a novel anode layer ion source, aiming to solve how to shield the magnetic field around the anode and how to weaken the etching of the cathode, thereby how to improve the working life of the ion source.

[0006] The technical solutions of the present invention are as follows:

[0007] The present invention provides a novel anode layer ion source, wherein the anode layer ion source comprises:

[0008] Magnetic base plate;

[0009] A magnetic conductive support column is provided on one side of the magnetic conductive base plate;

[0010] An inner cathode connected to a side of the magnetic support column facing away from the magnetic base plate;

[0011] an outer cathode, wherein an ion flow channel is formed between the inner cathode and the outer cathode, and an ion beam is generated in the ion flow channel;

[0012] A magnet frame is provided between the magnetic conductive bottom plate and the outer cathode;

[0013] A permanent magnet is disposed inside the magnet frame;

[0014] An outer shielding cover is provided above the outer surface of the inner cathode and the outer cathode facing the ion flow channel, and is used to prevent positive ions from bombarding the cathode surfaces of the inner cathode and the outer cathode;

[0015] an anode connected to the magnetic base plate via an insulating fastener, the anode being located in a space enclosed by the inner cathode, the outer cathode, the magnet frame, and the magnetic base plate, wherein the inner cathode, the outer cathode, the magnet frame, and the magnetic base plate are all insulated from the anode;

[0016] A magnetic shield is connected to the magnetic base plate via the insulating fasteners. The magnetic shield is arranged around the anode and is insulated from the inner cathode, the outer cathode and the anode. The magnetic shield is used to shield the magnetic field around the anode.

[0017] In some embodiments, the inner cathode, the outer cathode, the magnetic base plate, and the magnetic shield are made of magnetic conductive materials, and the outer shield, the anode, and the magnet frame are made of non-magnetic conductive materials.

[0018] In some embodiments, the thickness of the outer shield is in the range of 0.5 to 10 mm;

[0019] The height of the outer shielding cover from the outer surface of the inner cathode and the height of the outer shielding cover from the outer surface of the outer cathode are both in the range of 1 to 30 mm.

[0020] In some embodiments, the thickness of the magnetic shield ranges from 0.5 to 50 mm;

[0021] The distance between the outer surface of the magnetic shield and the inner surface of the inner cathode and the inner surface of the outer cathode are both in the range of 0.1 to 100 mm;

[0022] The distance between the inner surface of the magnetic shield and the outer surface of the anode is in the range of 0.1 to 100 mm.

[0023] In some embodiments, further comprising:

[0024] a spacing piece connecting the outer cathode and the outer shield, and connecting the inner cathode and the outer shield;

[0025] The height of the outer shield from the inner cathode and the height from the outer cathode are respectively equal to the thickness of the corresponding adjustable piece, and the two end surfaces of the corresponding adjustable piece are respectively located within the relative end surface range of the outer shield and the outer cathode.

[0026] In some embodiments, the material of the outer shield includes at least one of aluminum oxide, titanium oxide, silicon oxide, and boron nitride;

[0027] The material of the magnetic shield includes at least one of pure iron, pure cobalt, pure nickel, magnetic stainless steel and low carbon steel;

[0028] The material of the inner cathode, outer cathode and magnetic conductive bottom plate includes at least one of pure iron, pure nickel, pure cobalt and steel magnetic conductive plate;

[0029] The permanent magnet includes at least one of a rare earth permanent magnet and a ferrite permanent magnet, and the magnetic induction intensity of the magnetic pole surface of the permanent magnet is 20 to 1000 mT.

[0030] In some embodiments, the magnet frame and the permanent magnet are integrally arranged above the center of the magnetic conductive base plate;

[0031] There are multiple permanent magnets, and the multiple permanent magnets are distributed in an array inside the magnet frame.

[0032] In some embodiments, a uniform gas chamber is provided in the anode, and a uniform gas plate is provided in the uniform gas chamber; the anode layer ion source further comprises:

[0033] A vent pipe is connected to the bottom plate, and the vent pipe is in communication with the air-uniform chamber;

[0034] In some embodiments, the anode layer ion source further comprises a power supply, and the power supply mode of the anode layer ion source comprises at least one of direct current discharge, pulse discharge, radio frequency discharge, medium frequency discharge, composite pulse discharge, and high power pulse discharge;

[0035] The discharge voltage range of the power supply to the anode layer ion source is 0-5000V, and the discharge power density range of the anode layer ion source is 10-400W / cm 2 .

[0036] Beneficial effects: The present invention provides a new anode layer ion source, which prevents positive ions in the ion channel from bombarding the cathode surface by arranging outer shielding covers on the inner cathode and outer cathode surfaces, thereby effectively inhibiting cathode etching and preventing sample contamination; at the same time, by arranging magnetic shielding covers around the inner contours of the inner cathode and outer cathode inside the ion source, the magnetic field near the anode is shielded, the electromagnetic field distribution is optimized, the internal discharge of the ion source is reduced, the process stability is improved, and the working life of the anode layer ion source is increased. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a structural schematic diagram of half of the novel anode layer ion source of the present invention.

[0038] Figure 2 This is an overall cross-sectional view of the novel anode layer ion source of the present invention.

[0039] Figure 3 It is a schematic diagram of the installation of the outer shielding cover of the novel anode layer ion source of the present invention.

[0040] Figure 4 It is a schematic diagram of the installation of the magnetic shielding cover of the novel anode layer ion source of the present invention.

[0041] Figure 5 This is a magnetic flux distribution diagram of the novel anode layer ion source of the present invention.

[0042] Figure 6 This is the electric field line distribution diagram of the novel anode layer ion source of the present invention.

[0043] Figure 7 This is the ion distribution diagram of the novel anode layer ion source of the present invention.

[0044] Description of reference numerals:

[0045] 1-Second shielding cover; 2-Outer cathode; 3-Outer magnetic shield; 4-Anode; 5-Gas-uniform chamber; 6-Height-limiting column; 7-Magnet frame; 8-Inner magnetic shield; 9-Gas-uniform plate; 10-Outer shell; 11-Bottom plate; 12-Inner cathode; 13-First shielding cover; 14-Water inlet pipe; 15-Water inlet hole; 16-Ventilation pipe; 17-Sealing assembly; 18-Glass sheet; 19-Mounting card seat; 20-Permanent magnet; 21-Magnetic base; 22-Magnetic support pillar; 23-Magnetic shielding cover. DETAILED DESCRIPTION

[0046] The present invention provides a novel anode layer ion source. To make the purpose, technical solution and effect of the present invention clearer and more specific, the present invention is further described in detail below. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0047] It should be noted that when a component is referred to as being “fixed to” or “disposed on” another component, it may be directly on the other component or indirectly on the other component. When a component is referred to as being “connected to” another component, it may be directly connected to the other component or indirectly connected to the other component.

[0048] It should also be noted that the same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there are terms such as "upper", "lower", "left", "right", etc. indicating directions or positional relationships, they are based on the directions or positional relationships shown in the drawings. This is only for the convenience of describing the present invention and simplifying the description, and does not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction. Therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting this patent. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0049] Currently, the anode layer ion source is developing towards higher discharge power in order to obtain a larger output beam current to improve the cleaning, etching, and deposition effects. However, the enhanced discharge, on the one hand, leads to intensified cathode etching of the anode layer ion source, causing serious contamination of the sample; on the other hand, it is easy to cause strong "sparking" between the anode and cathode, seriously affecting the stability of the process.

[0050] In order to solve the above problems, the present invention provides a new anode layer ion source, which isolates the discharge ions from contacting the cathode surface by adding an insulating shield; and changes the electromagnetic field distribution between the cathode and cathode of the ion source by adding a magnetic shield, shielding the magnetic field near the anode inside the ion source, thereby reducing the contamination caused by cathode sputtering, and improving the service life of the ion source and the quality of the deposited coating; Figure 1 As shown, it includes:

[0051] Magnetic base plate;

[0052] An inner cathode 12 connected to the magnetic conductive bottom plate;

[0053] An outer cathode 2, wherein an ion flow channel is provided between the inner cathode 12 and the outer cathode 2, and the ion flow channel is used for ion beam ejection;

[0054] a magnet frame 7, one end of the magnet frame 7 being connected to the magnetic base plate, and the other end of the magnet structure being connected to the outer cathode 2; the outer cathode 2 being connected to the magnetic base plate and / or the magnet structure;

[0055] The permanent magnet 20 is arranged inside the magnet frame 7;

[0056] An outer shielding cover is provided directly above the inner cathode 12 and the outer cathode 2 to prevent positive ions from bombarding the cathode surfaces of the inner cathode 12 and the outer cathode 2;

[0057] an anode 4 connected to the magnetic base plate, the anode being located in a space enclosed by the inner cathode 12, the outer cathode 2, the magnet structure, and the magnetic base plate, wherein the inner cathode 12, the outer cathode 2, the magnet frame 7, and the magnetic base plate are all insulated from the anode 4;

[0058] The magnetic shielding cover 23 is connected to the magnetic conductive bottom plate. The magnetic shielding cover 23 is arranged around the anode 4 and is used to shield the magnetic field around the anode.

[0059] It is worth noting that the present invention can effectively suppress cathode etching by installing an insulating outer shielding cover with high temperature resistance and low sputtering yield above the inner and outer cathodes of the anode layer ion source; at the same time, the present invention installs a magnetic shielding cover with magnetic conductivity between the inner and outer cathodes and the anode, which can shield the magnetic field between the cathode and the cathode, and effectively prevent the occurrence of "sparking" between the cathode and the cathode.

[0060] In a preferred embodiment of the present invention, the inner cathode 12, the outer cathode 2, the magnetic conductive bottom plate and the magnetic shield 23 are all made of magnetic conductive materials, and the outer shield and the anode 4 are made of non-magnetic conductive materials.

[0061] Specifically, the material of the outer shield includes at least one of aluminum oxide, titanium oxide, silicon oxide, and boron nitride;

[0062] The material of the magnetic shield 23 includes at least one of pure iron, pure cobalt, pure nickel, magnetic stainless steel and low carbon steel;

[0063] The material of the inner cathode 12, the outer cathode 2, and the magnetic conductive bottom plate includes at least one of pure iron, pure nickel, pure cobalt, and SU430 steel magnetic conductive plate;

[0064] The permanent magnet 20 includes at least one of a ferromagnetic rare earth permanent magnet and a ferrite permanent magnet, and the magnetic induction intensity of the magnetic pole surface of the permanent magnet is 20 to 1000 mT;

[0065] The anode 4 and the magnet frame 7 are made of non-magnetic materials.

[0066] It should be noted that the outer shielding cover is made of insulating material, so it has the characteristics of insulation, high temperature resistance, high mechanical properties and low sputtering yield; the magnetic shielding cover 23 is made of soft magnetic material with high magnetic permeability, high temperature resistance and high mechanical properties; the material of the inner cathode 12, the outer cathode 2, the magnetic support 22 and the magnetic base 21 is at least one of all magnetic materials such as soft magnetic pure iron, pure nickel, pure cobalt, SU430 steel magnetic plate, etc.

[0067] Furthermore, the second shielding cover 1 and the first shielding cover 13 of this embodiment are both made of alumina material; the inner cathode 12 and the outer cathode 2 are both made of magnetic conductive material, the outer magnetic conductive cover 3 and the inner magnetic conductive cover 8 are made of magnetic conductive material, and the anode 4 is a circular ring body made of conductive and non-magnetic material, and the anode 4 is a non-magnetic stainless steel material.

[0068] In a preferred embodiment of the present invention, Figure 1 or Figure 2 As shown, the magnetic conductive base plate includes:

[0069] Magnetic base 21;

[0070] The magnetic conductive support 22 is provided on the magnetic conductive base 21;

[0071] A height limiting column 6 is provided on the magnetic base 21;

[0072] The magnet frame 7 is arranged on the magnetic base 21;

[0073] A permanent magnet 20 or an electromagnet is disposed inside the magnet frame 7;

[0074] The magnetic conductive pillar 22 connects the magnetic conductive base 21 and the inner cathode 4 , the height limiting pillar 6 abuts against the magnetic shield 23 , and the outer cathode 2 is connected to the magnet frame 7 .

[0075] The anode layer ion source of this embodiment is arranged in an axisymmetric manner. Figure 1 or Figure 2 As shown, the magnetic conductive pillar 22 is arranged at the center of the magnetic conductive base 21;

[0076] The height limiting column 6 is provided on the upper side of the magnetic base 21;

[0077] The magnet frame 7 is arranged at the edge of the magnetic base 21;

[0078] There are multiple permanent magnets 20 , and the multiple permanent magnets 20 are distributed in an array inside the magnet frame 7 .

[0079] Specifically, the magnetic base 21 is disc-shaped, the axis of the magnetic pillar 22 coincides with the axis of the magnetic base 21, and the inner cathode 12 is located at the axial position, that is, the inner cathode 12 is arranged directly above the magnetic pillar 22; the magnetic pillar 22 is arranged directly above the center of the magnetic base 21; the outer cathode 2 is arranged directly above the magnet frame 7; the magnet frame is arranged directly above the edge of the magnetic base, and a magnet mounting groove is provided inside the magnet frame, and the permanent magnet is arranged in the magnet mounting groove; the height limiting column 6 is located at the upper end of the magnetic base 21, the anode 4 is arranged at the upper end of the height limiting column 6, and the anode 4 is arranged in the space surrounded by the inner cathode 12, the outer cathode 2, the magnet frame 7, the magnetic pillar 22 and the magnetic base 21, and is insulated from the inner cathode 12, the outer cathode 2, the magnet frame 7, the magnetic pillar 22 and the magnetic base 21; the insulating outer shielding cover is arranged directly above the inner cathode 12 and the outer cathode 2, and is separated from the inner cathode 12 and the outer cathode 2 by a certain distance.

[0080] Furthermore, the number of the permanent magnets 20 is set to sixteen, and the sixteen permanent magnets are distributed inside the magnet frame in a circular array;

[0081] It should be noted that the permanent magnet 20 can be shaped like one or more of a cylinder, a cube, or a right prism. The permanent magnet 20 can be directly connected to the outer cathode 12 or the magnetic base 21, or connected to the outer cathode 12 or the magnetic base 21 via a soft magnetic conductive block, without specific limitations herein. The magnetic shield 23 does not directly contact the inner cathode 12, the outer cathode 2, and the anode 4, but is secured thereto via fasteners (i.e., height-limiting posts 6) made of one or more insulating and high-temperature-resistant materials, such as polymers and ceramics.

[0082] like Figure 2 As shown, an outer cathode 2 is provided outside the inner cathode 12. The outer cathode 2 surrounds the outer side of the inner cathode 12. A gap is provided between the inner cathode 12 and the outer cathode 2. The gap serves as an ion flow channel for ion beam ejection. In this embodiment, the outer cathode 2 is specifically located above the outer side of the inner cathode 12. One end of the permanent magnet 20 abuts against the lower surface of the outer cathode 2, and the other end of the permanent magnet 20 is connected to the yoke of the inner cathode 12. It should be noted that the yoke generally refers to a soft magnetic material that does not generate a magnetic field (i.e., magnetic lines of force) itself and only transmits magnetic lines of force in the magnetic circuit. The yoke is generally made of soft iron, A3 steel, and soft magnetic alloy with relatively high magnetic permeability.

[0083] In another preferred embodiment of the present invention, the magnet frame 7 and the permanent magnet 20 can be arranged as a whole just above the center of the magnetic base 21, replacing the position of the magnetic support 22 in the above-mentioned scheme; at the same time, the magnetic support 22 can be arranged as a whole just above the edge of the magnetic base 21, replacing the position of the magnet frame 7 and the permanent magnet 20 in the above-mentioned scheme; 16 permanent magnets 20 are evenly arranged between the inner cathode 12 and the outer cathode 2, and the permanent magnets 20 are surrounded in a circle below the outer cathode 2, and the permanent magnets are columnar permanent magnets or electromagnets.

[0084] In a preferred embodiment of the present invention, the anode layer ion source further comprises:

[0085] A spacing piece connecting the outer cathode 2 and the outer shield, and connecting the inner cathode 12 and the outer shield;

[0086] The height of the outer shield from the inner cathode and the height from the outer cathode are respectively equal to the corresponding thickness of the spacing piece, and the two end surfaces of the corresponding spacing piece are respectively located within the relative end surface range of the outer shield and the outer cathode.

[0087] It should be noted that the outer shielding cover is not in direct contact with the inner cathode 12 and the outer cathode 2, and the insulating shielding cover is fixed by one or more insulating and high-temperature resistant materials such as polymers and ceramics as connecting materials (i.e., spacers).

[0088] Specifically, the spacer in this embodiment is made of glass sheets. The first shielding cover 13 is fixed to the inner cathode 12 by insulating tape and several glass sheets, and the second shielding cover 1 is fixed to the outer cathode 2 by insulating tape and several glass sheets. The thickness of the spacer is determined by the number of glass sheets.

[0089] In a preferred embodiment of the present invention, Figure 1 or Figure 2 As shown, the number of the pitch adjusters is set to at least two; the outer shielding cover includes:

[0090] A first shielding cover 13, wherein a distance adjusting piece is connected between the inner cathode 12 and the first shielding cover 13;

[0091] a second shielding cover 1, wherein another distance adjusting piece is connected between the outer cathode 2 and the second shielding cover 1;

[0092] The magnetic shield 23 includes:

[0093] An inner magnetic conductive cover 8 is connected to the height limiting column 6;

[0094] The outer magnetic conductive cover 3 is connected to the height limiting column 6;

[0095] The first shielding cover 13 is located outside the inner cathode 12 , the second shielding cover 1 is located outside the outer cathode 2 , the inner magnetic conductive cover 8 is located inside the inner cathode 12 , and the outer magnetic conductive cover 3 is located inside the outer cathode 2 .

[0096] It should be noted that the outer shielding cover can be installed only on the inner cathode 12 or above the outer cathode 12 as in the above embodiment, but is not limited thereto. It can also be installed above both the inner cathode 12 and the outer cathode 2, that is, the outer shielding cover is an integrated structure.

[0097] Specifically, if Figure 1 or Figure 2 As shown, an anode 4 is disposed between the inner cathode 12 and the outer cathode 2. The anode 4 surrounds the inner cathode 12, and the outer magnetic shield 3 surrounds the anode 4 and is fixed between the outer cathode 2, the inner cathode 12, and the anode 4 by insulating fasteners (i.e., height limiting columns 6). The anode 4 has a circular ring structure, and the inner cathode 12 is located above the anode 4. The lower surface of the inner cathode 12 is higher than the upper surface of the anode 4. The anode 4, the inner cathode 12, and the outer cathode 2 form a discharge chamber. A vent is provided in the anode 4 for connecting an external working gas.

[0098] like Figure 3 As shown, in this example, the first shielding cover 13 and the second shielding cover 1 are fixed to the inner cathode 12 and the outer cathode 2 by means of insulating tape and glass sheets 18. The distance between the first shielding cover 13, the second shielding cover 1 and the inner cathode 12 and the outer cathode 2 can be adjusted between 5mm, 7mm, 9mm, 11mm and 13mm by increasing or decreasing the number of glass sheets 18. Figure 4 As shown, in this example, the magnetic shield 23 is disassembled into an inner magnetic shield 8 and an outer magnetic shield 3, which are fixed to the anode 4 via a height limiting column 6 and an insulating base 19. The insulating base 19 is connected to the height limiting column 6 and the magnetic base 21 respectively.

[0099] In a preferred embodiment of the present invention, the thickness of the outer shielding cover ranges from 0.5 to 10 mm;

[0100] The height of the outer shield from the outer surface of the inner cathode 12 and the outer surface of the outer cathode 2 are both in the range of 1 to 30 mm;

[0101] The thickness of the magnetic shield 23 ranges from 0.5 to 50 mm;

[0102] The distance between the outer surface of the magnetic shield 23 and the inner surface of the inner cathode 12 and the inner surface of the outer cathode 2 is in the range of 0.1 to 100 mm;

[0103] The distance between the inner surface of the magnetic shield 23 and the outer surface of the anode 4 is in the range of 0.1 to 100 mm.

[0104] It should be noted that the lower surface contour of the outer shielding cover can be parallel to the outer surface contours of the inner cathode 12 and the outer cathode 2, or it can be non-parallel; the outer surface contour of the magnetic shielding cover 23 can be parallel to the inner surface contours of the inner cathode 12 and the outer cathode 2, or it can be non-parallel; the inner surface contour of the magnetic shielding cover 23 can be parallel to the outer surface contour of the anode 4, or it can be non-parallel; no specific limitation is made here.

[0105] Specifically, the thickness of the first shielding cover 13 is 2 mm, and the distance from the inner cathode 12 is 7 mm; the thickness of the second shielding cover 1 is 2 mm, and the distance from the outer cathode 2 is 9 mm; the thickness of the outer magnetic conductive cover 3 and the inner magnetic conductive cover 8 is 3 mm, and the cross-sectional profile is parallel to the inner profile of the outer cathode 2 and the inner cathode 12, and the distance is 2 mm.

[0106] In a preferred embodiment of the present invention, the anode layer ion source further comprises a power supply, and the power supply mode of the power supply to the novel anode layer ion source includes at least one of direct current discharge, pulse discharge, radio frequency discharge, medium frequency discharge, composite pulse discharge, and high power pulse discharge;

[0107] The discharge voltage range of the power supply to the novel anode layer ion source is 0-5000V, and the discharge power density range of the novel anode layer ion source is 10-400W / cm 2 .

[0108] The anode layer ion source of the present invention is equipped with an insulating outer shield with high temperature resistance and low sputtering yield above the inner and outer cathodes, which can effectively suppress cathode etching and prevent sample contamination. Furthermore, a magnetic shield with magnetic conductivity is installed between the inner and outer cathodes and the anode to shield the magnetic field between the cathode and cathode, effectively preventing the occurrence of "sparking" between the cathode and cathode, and improving process stability. The present invention can effectively improve the cleanliness of the ion beam of the anode layer ion source, reduce contamination, and improve stability, providing guidance for the development of high-power clean anode layer ion sources.

[0109] In other words, by providing a first shield 13 and a second shield 1 on the surfaces of the inner cathode 12 and the outer cathode 2, positive ions in the ion channel are prevented from bombarding the cathode surfaces, reducing the amount of metal atoms generated by sputtering. Simultaneously, by adding an outer magnetic shield 3 and an inner magnetic shield 8 around the inner contours of the inner cathode 12 and the outer cathode 2 within the ion source, the electromagnetic field distribution is optimized, shielding the magnetic field near the anode 4 and reducing the sputtering of cathode atoms caused by internal discharge. This also effectively improves the cleanliness of the ion beam during processes such as processing, heating, cleaning, etching, sputtering, and ion implantation.

[0110] like Figure 2 、 Figure 5 and Figure 6 As shown, in this embodiment, a closed magnetic circuit is formed by setting a permanent magnet 20 between the inner cathode 12 and the outer cathode 2, and a magnetic field parallel to the anode chamfered surface is formed between the inner cathode 12 and the outer cathode 2, as shown in FIG. Figure 5 As shown; the anode 4 is connected to a positive voltage to form an anode, the inner cathode 12 and the outer cathode 2 are grounded to form a cathode, and an electric field is formed in the region between the cathode and the anode, that is, an electric field is formed between the anode 4 and the inner cathode 12, and between the anode 4 and the outer cathode 2, as shown Figure 6 As shown, the direction of the electric field is perpendicular to the direction of the magnetic field, forming an electromagnetic coupling field. Under the action of this electromagnetic coupling field, the electron cloud can drift in a closed manner within the range of this electromagnetic coupling field, thereby increasing the number of collisions and significantly increasing the ionization rate. The presence of a high-density electron cloud forms an anode layer with a very high potential gradient on the surface of the anode 4. The working gas enters the interior of the anode 4 through the vent tube 16. When the working gas is ionized in the annular electron cloud, it is immediately pushed by this high potential gradient and emitted along the normal direction of the anode plate surface, thereby becoming the required high-energy charged positive ions. A second shielding cover 1 (i.e., an outer cathode insulating shielding cover) is added to the surface of the outer cathode 2, and a first shielding cover 13 (an inner cathode insulating shielding cover) is added to the surface of the inner cathode 12, isolating the ion flow channel from most of the cathode surface, preventing the positive ions in the ion flow channel from bombarding the cathode surface, thereby reducing the number of cathode sputtered atoms.

[0111] The second shielding cover 1 and the first shielding cover 13 are made of alumina. The sputtering yield of alumina is much lower than that of metal. The second shielding cover 1 and the first shielding cover 13 are suspended and installed by insulating tape and glass sheet 18. The energy of ions bombarding them is very small. Therefore, the sputtering contamination of ceramic materials can be ignored. Figure 7 As shown in the figure, after adding the outer shield, the distribution area of ​​ions is reduced and the ion density in the corresponding area is increased. At the same time, it can also effectively improve the cleanliness of the ion beam during processing, heating, cleaning, etching, sputtering and ion implantation.

[0112] like Figure 5 As shown, an outer magnetic shield 3 is added to the inner side of the outer cathode 2, and an inner magnetic shield 8 is added to the outer side of the inner cathode 12. The magnetic field lines passing through the anode 4 are directed into the interior of the magnetic shield, shielding the magnetic field near the surface of the anode 4. Discharge requires the action of an electromagnetic coupling field. After adding the outer magnetic shield 3 and the inner magnetic shield 8, the magnetic field between the outer cathode 2 and the inner cathode 12 and the anode 4 inside the ion source is shielded. After adding the outer magnetic shield 3 and the inner magnetic shield 8, cathode sputtering caused by discharge inside the ion source and the possible short circuit between the cathode and the cathode are eliminated, thereby improving the service life of the ion source and the quality of the deposited coating.

[0113] In a preferred embodiment of the present invention, Figure 2 As shown, the anode 4 is provided with a uniform gas chamber 5, the uniform gas chamber 5 is provided with a uniform gas plate 9, and the height limiting column 6 is provided with a connecting hole; the anode layer ion source also includes:

[0114] A bottom plate 11, wherein the bottom plate 11 is provided with a through hole;

[0115] The housing 10 is provided on the bottom plate 11;

[0116] A vent pipe 16 is connected to the bottom plate 11 and is connected to the air-uniform chamber 5 through the through hole and the communication hole;

[0117] Two water inlet pipes 14 (circular) are connected to the bottom plate 11. The water inlet pipes 14 are provided with water inlet holes 15. Water is injected through the water inlet holes 15 of the water inlet pipes 14 to achieve the purpose of cooling the ion source. It should be noted that the water inlet holes 15 of the water inlet pipes 14 are not connected to the uniform gas chamber 5.

[0118] The magnetic conductive bottom plate is disposed on the bottom plate 11 , and the magnet structure is disposed on the housing 10 .

[0119] The novel anode layer ion source in the present scheme also includes a base plate 11, which is disc-shaped, and an inner cathode 12 is coaxially fixedly arranged in the middle position of the base plate 11. A permanent magnet frame 7 is arranged above the base plate 11, and the magnet frame 7 is coaxially arranged with the inner cathode 12. A permanent magnet 20 is mounted on the magnet frame 7, and a limited height column 6 is arranged above the chassis and below the lower surface of the anode 4 and coaxial with the vent pipe. A water inlet pipe 14 passes through the limited height column 6 and extends through the base plate 11. The limited height column 6 separates the inner cathode 12 from the anode 4. A sealing assembly 17 is provided at the position where the water pipe 14 passes through the base plate 11. The sealing assembly 17 is used to seal the gap between the water inlet pipe 14 and the vent pipe 16 and the base. An ion source housing 10 is mounted on the base plate 11, and the ion source housing 10 is sleeved on the outside of the magnet frame 7. The upper part of the ion source housing 10 is sleeved on the outside of the outer cathode 2. The novel anode layer ion source is preferably an axisymmetric structure formed about the central axis. The overall magnetic field distribution of the symmetrical structure is uniform, the structure is simple, and it is easy to process.

[0120] In summary, the present invention provides a new anode layer ion source, which prevents positive ions in the ion channel from bombarding the cathode surface by arranging an outer shielding cover on the inner cathode and outer cathode surfaces, thereby effectively suppressing cathode etching and preventing sample contamination; at the same time, by arranging a magnetic shielding cover around the inner contours of the inner cathode and outer cathode inside the ion source, the magnetic field near the anode is shielded, the electromagnetic field distribution is optimized, the internal discharge of the ion source is reduced, the process stability is improved, and the working life of the anode layer ion source is improved.

[0121] It should be understood that the application of the present invention is not limited to the above examples. For those skilled in the art, improvements or changes can be made based on the above description. All these improvements and changes should fall within the scope of protection of the claims attached to the present invention.

Claims

1. A novel anode layer ion source, characterized in that: It includes: Magnetic base plate; A magnetic conductive support column is provided on one side of the magnetic conductive base plate; An inner cathode connected to a side of the magnetic support column facing away from the magnetic base plate; an outer cathode, wherein an ion flow channel is formed between the inner cathode and the outer cathode, and an ion beam is generated in the ion flow channel; A magnet frame is provided between the magnetic conductive bottom plate and the outer cathode; A permanent magnet is disposed inside the magnet frame; An outer shielding cover is provided above the outer surface of the inner cathode and the outer cathode facing the ion flow channel, and is used to prevent positive ions from bombarding the cathode surfaces of the inner cathode and the outer cathode; an anode connected to the magnetic base plate via an insulating fastener, the anode being located in a space enclosed by the inner cathode, the outer cathode, the magnet frame, and the magnetic base plate, wherein the inner cathode, the outer cathode, the magnet frame, and the magnetic base plate are all insulated from the anode; A magnetic shield is connected to the magnetic base plate via the insulating fasteners. The magnetic shield is arranged around the anode and is insulated from the inner cathode, the outer cathode and the anode. The magnetic shield is used to shield the magnetic field around the anode.

2. The novel anode layer ion source according to claim 1, characterized in that: The inner cathode, the outer cathode, the magnetic conductive bottom plate and the magnetic shield are made of magnetic conductive materials, and the outer shield, the anode and the magnet frame are made of non-magnetic conductive materials.

3. The novel anode layer ion source according to claim 1, characterized in that: The thickness of the outer shielding cover ranges from 0.5 to 10 mm; The height of the outer shielding cover from the outer surface of the inner cathode and the height of the outer shielding cover from the outer surface of the outer cathode are both in the range of 1 to 30 mm.

4. The novel anode layer ion source according to claim 1, characterized in that: The thickness of the magnetic shield ranges from 0.5 to 50 mm; The distance between the outer surface of the magnetic shield and the inner surface of the inner cathode and the inner surface of the outer cathode are both in the range of 0.1 to 100 mm; The distance between the inner surface of the magnetic shield and the outer surface of the anode is in the range of 0.1 to 100 mm.

5. The novel anode layer ion source according to claim 2, characterized in that: Also includes: a spacing piece connecting the outer cathode and the outer shield, and connecting the inner cathode and the outer shield; The height of the outer shield from the inner cathode and the height from the outer cathode are respectively equal to the thickness of the corresponding adjustable piece, and the two end surfaces of the corresponding adjustable piece are respectively located within the relative end surface range of the outer shield and the outer cathode.

6. The novel anode layer ion source according to claim 2, characterized in that: The material of the outer shield comprises at least one of aluminum oxide, titanium oxide, silicon oxide, and boron nitride; The material of the magnetic shield includes at least one of pure iron, pure cobalt, pure nickel, magnetic stainless steel and low carbon steel; The material of the inner cathode, outer cathode and magnetic conductive bottom plate includes at least one of pure iron, pure nickel, pure cobalt and magnetic conductive steel plate; The permanent magnet includes at least one of a rare earth permanent magnet and a ferrite permanent magnet, and the magnetic induction intensity of the magnetic pole surface of the permanent magnet is 20 to 1000 mT.

7. The novel anode layer ion source according to claim 2, characterized in that: The magnet frame and the permanent magnet are integrally arranged above the center of the magnetic conductive bottom plate; There are multiple permanent magnets, and the multiple permanent magnets are distributed in the magnet frame in an array.

8. The novel anode layer ion source according to claim 2, characterized in that: The anode is provided with a gas-uniform chamber, and the gas-uniform chamber is provided with a gas-uniform plate; the anode layer ion source further comprises: A ventilation pipe is connected to the bottom plate, and the ventilation pipe is communicated with the air uniforming chamber.

9. The novel anode layer ion source according to claim 2, characterized in that: The anode layer ion source further includes a power supply, and the power supply mode of the anode layer ion source includes at least one of direct current discharge, pulse discharge, radio frequency discharge, and medium frequency discharge; The discharge voltage range of the power supply to the anode layer ion source is 0-5000V, and the discharge power density range of the anode layer ion source is 10-400W / cm 2 .

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