CN111621760A

CN111621760A - Rotary cathode magnetic bar for magnetron sputtering

Info

Publication number: CN111621760A
Application number: CN202010619377.0A
Authority: CN
Inventors: 来华杭; 俞峰; 刘杰; 施成亮; 江嘉; 周海龙
Original assignee: Zhejiang Shangfang Electronic Equipment Co ltd
Current assignee: Zhejiang Shangfang Electronic Equipment Co ltd
Priority date: 2020-06-30
Filing date: 2020-06-30
Publication date: 2020-09-04

Abstract

The invention relates to a rotary cathode magnetic rod for magnetron sputtering, which comprises a magnetic rod bracket and magnets fixed on the surface of the magnetic rod bracket, wherein the magnets comprise a middle magnet and end magnets along the length direction of the magnetic rod bracket, the middle magnets are three rows which are sequentially arranged, namely a middle row and two side rows, and the polarities of the magnets in the middle of the adjacent rows are reversely arranged relative to the direction of the surface of the magnetic rod bracket. The end magnet includes: the polarity direction of the middle group is the same as that of the middle row, and the middle row further extends to the end part of the magnetic rod bracket; and the polarity direction of the peripheral group is the same as that of the two side rows, and the two side rows further extend to the end part of the magnetic bar bracket along a linear enclosing path and are intersected and enclosed on the periphery of the middle group. The magnet cloth at the end parts of the two ends of the magnetic rod support in the length direction is fixed in a specific arrangement mode, so that the magnetic fields at the two ends are attenuated, and the effective utilization rate of the target material is improved under the condition that the length of the effective coating area is not shortened.

Description

Rotary cathode magnetic bar for magnetron sputtering

Technical Field

The invention relates to the field of sputtering coating processes, in particular to a rotary cathode magnetic rod for measuring and controlling sputtering.

Background

Magnetron sputtering coating is a widely-used coating deposition process at present. The sputtering coating is far away from that the inert gas bombards the surface of the target under the action of an electric field, and molecules, atoms, ions, electrons and the like on the surface of the target are sputtered out and splashed onto the substrate to deposit and form a film.

In the coating process, the quality requirement on the magnetron sputtering coating equipment is high, wherein the magnetic field intensity distribution of a magnetron sputtering cathode is particularly important. In general, in the coating process, due to the fact that the ratio of the magnetic field intensity at the two end parts of the target material to the magnetic field intensity in the middle part of the target material is not proper, the etching speed of the end part area of the target material is higher than that of the middle part area of the target material, the surface finishing etching profile of the target material is not uniform, too-deep etching grooves appear at the two end parts of the target material, and a shallow etching groove appears in the middle part of the. When the target material is replaced, the target material is replaced according to the condition that the deepest etching groove is close to the thickness of the target material, and at the moment, most of the etching grooves in the middle are still shallow, so that the utilization rate of the target material is reduced, waste is caused, and the coating cost is increased.

Disclosure of Invention

In view of this, it is necessary to provide a rotary cathode bar for magnetron sputtering, which is directed to the problem of low target utilization.

A rotary cathode magnetic rod for magnetron sputtering comprises a magnetic rod support and magnets fixed on the surface of the magnetic rod support, wherein the magnets comprise middle magnets and end magnets along the length direction of the magnetic rod support, the middle magnets are sequentially arranged in three rows, namely a central row and two side rows, and the polarities of the magnets in the middle of adjacent rows are reversely arranged relative to the direction of the surface of the magnetic rod support;

the end magnet includes:

the polarity direction of the middle group is the same as that of the middle row, and the middle row further extends to the end part of the magnetic rod bracket;

and the polarity direction of the peripheral group is the same as that of the two side rows, and the two side rows further extend to the end part of the magnetic bar bracket along a linear enclosing path and are intersected and enclosed on the periphery of the middle group.

Preferably, in the length direction of the magnetic rod support, the middle magnets in the same row are located in the middle of the magnetic rod support and adjacent to the end of the magnetic rod support are a plurality of magnets arranged at intervals.

Preferably, the middle group has at least two magnets, and the size of each magnet of the middle group extending to the end of the magnetic rod bracket is gradually reduced and the magnetic field is gradually weakened.

Preferably, the middle group is two magnets.

Preferably, the peripheral group comprises two enclosure units at two sides of the middle group and an end point magnet aligned with the middle group, and the two enclosure units extend towards the end part of the magnetic rod bracket and are intersected with the end point magnet.

Preferably, the two enclosure units are symmetrically arranged, and in the length direction of the magnetic rod bracket, the end point magnet and the nearest magnet in each enclosure unit are arranged in a staggered manner.

Preferably, each enclosure unit comprises a plurality of magnets arranged along the enclosure path, and the magnets of the same enclosure unit are the same or different in size.

Preferably, the inclination angle of the enclosing path is 15-60 degrees relative to the length direction of the magnetic rod bracket.

Preferably, the inclination angle of the encircling path is 25-45 degrees.

The application also provides a magnetron which comprises a cylindrical target material, wherein the inside of the target material is used as an installation chamber, and a rotary cathode magnetic rod for magnetron sputtering is arranged in the installation chamber.

According to the rotary cathode magnetic rod for magnetron sputtering, the magnet cloth at the end parts of the two ends in the length direction of the magnetic rod support is fixed in a specific arrangement mode, so that the magnetic fields at the two ends are attenuated, and the effective utilization rate of a target material is improved under the condition that the length of an effective coating area is not shortened.

Drawings

FIG. 1 is a schematic structural diagram of a rotating cathode bar magnet according to an embodiment;

FIG. 2 is an enlarged schematic view of detail A of FIG. 1;

fig. 3 is another angle view of fig. 2.

FIG. 4 is a graph illustrating the relationship between the target position and the magnetic field strength in one embodiment;

FIG. 5 is a schematic cross-sectional view of a magnetic rod of a rotating cathode in the length direction according to an embodiment;

FIG. 6 is a schematic diagram of a magnetron in one embodiment;

FIG. 7 is a schematic cross-sectional view taken at B in FIG. 6;

FIG. 8 is a schematic diagram of an embodiment of a magnetron with the target removed;

FIG. 9 is a schematic cross-sectional view taken at C of FIG. 8;

FIG. 10 is a schematic view of a spacing adjustment base according to an embodiment of the present invention;

the reference numbers illustrate:

1. rotating the cathode magnetic rod; 2. a magnetic bar support; 3. a magnet; 4. a middle magnet; 41. a compensation magnet; 5. An end magnet; 51. an intermediate group; 52. a peripheral group; 53. a gasket;

6. an end point magnet;

7. a magnetron; 8. a target material;

9. a support frame; 91. a bayonet; 92. an avoidance groove;

10. a cooling water pipe;

11. a space adjusting seat; 111. a U-shaped support; 112. an adjusting block; 113. adjusting the screw rod; 114. cushion blocks;

12. a sealing cover; 121. a housing; 1211. flanging; 122. sealing the end;

13. a fastener;

14. a connecting member.

Detailed Description

As shown in fig. 1-2, the present application provides a rotary cathode magnetic rod 1 for magnetron sputtering, including a magnetic rod support 2 and magnets 3 fixed on the surface of the magnetic rod support 2, along the length direction of the magnetic rod support 2, the magnets 3 include middle magnets 4 and end magnets 5, the middle magnets 4 are arranged in three rows in sequence, respectively in the middle and two side rows, and for the direction of the surface of the magnetic rod support 2, the polarities of the middle magnets 4 in adjacent rows are arranged in opposite directions. The end magnet 5 includes:

the middle group 51 has the same polarity direction as the middle row and is further arranged from the middle row to the end part of the magnetic rod bracket 2 in an extending way;

the polarity direction of the peripheral group 52 is the same as that of the two side rows, and the two side rows extend to the end of the magnetic bar bracket 2 along the straight enclosing path and are intersected and enclosed on the periphery of the middle group.

In this embodiment, be in 5 peripheral groups of tip magnet at bar magnet support 2 along length direction both ends, magnet 3 that is in both sides limit row by middle part magnet 4 respectively draws close to the intersection along the straight line to the centre, the effective decay of magnetic field intensity at both ends like this for with the magnetic field intensity evenly distributed of middle part magnet 4 production, at the sputter coating in-process, the etching groove degree of depth that the sputtering left on the target distributes unanimously, the target effective utilization rate has been improved, it improves to 80% to obtain the target utilization rate through the experiment.

In this embodiment, the magnetism of the magnet 3 in the central row of the magnetic rod support 2 is opposite to that of the magnet 3 in the two side rows, so that the magnetic lines of force are respectively led to the middle from the two side edges or to the two side edges from the middle, and the magnetic lines of force parallel to the surface of the target are formed on the surface of the target, so that the movement direction of electrons is constrained under the action of orthogonal electromagnetic fields, thereby controlling the area and concentration of the plasma track and making the magnetic field intensity distribution on the surface of the target more uniform.

In the embodiment, the middle magnets 4 in the same row in the length direction of the magnetic rod support 2 are the whole magnets 3 in the middle, and the adjacent ends are a plurality of magnets 3 arranged at intervals.

The whole magnet 3 is also understood as that a plurality of magnets 3 with the same specification and size are sequentially arranged along the length direction of the magnetic rod bracket 2 due to the limitation of the length and size of the magnet 3, and a magnetic field with the uniform intensity is generated.

As shown in fig. 3, when the length dimension of the effective coating area changes, the target length dimension also changes, so that when the distance between the middle magnets 4 adjacent to the end magnets 5 is not enough to arrange the next middle magnet 4, the compensation magnet 41 is further disposed between the middle magnets 4 adjacent to the end magnets.

In the present embodiment, the compensation magnets 41 are a plurality of magnets 3 with smaller length, which are arranged at intervals, and may be rectangular or square, and the number of the compensation magnets is based on the gap that can be filled between the middle magnet 4 and the end magnet 5.

In this embodiment, the middle group 51 at both ends has at least two magnets 3, and the size of each magnet 3 of the middle group 51 extending to the end of the bar magnet holder 2 becomes gradually smaller and the magnetic field becomes gradually weaker. The strength of the magnetic field generated by the magnets 3 depends on their magnetism and volume, and the intermediate group 51 can adjust the strength of the magnetic field and the magnetic flux by arranging the magnets 3 of specific magnetism and size according to the requirements.

In one embodiment thereof, the middle set 51 is two magnets 3.

In this embodiment, the peripheral group 52 includes two enclosure units at two sides of the middle group 51, and the end magnets 6 aligned with the middle group 51, and the two enclosure units extend toward the end of the magnetic rod bracket 2 and meet the end magnets 6.

Furthermore, the two surrounding units are symmetrically arranged, and in the length direction of the magnetic rod bracket 2, the end point magnet 6 and the magnet 3 which is most adjacent to each surrounding unit are arranged in a staggered mode.

Specifically, the enclosure unit comprises a plurality of magnets 3 arranged along an enclosure path, and the magnets 3 of the same enclosure unit are the same in size or different in size. According to the requirement of the magnetic field intensity, the size or the material of each magnet in the enclosure unit can be flexibly replaced.

As shown in fig. 4, the magnets of the enclosing units at the two ends are linearly closed and converged by the end point magnets 6, so that the magnetic fields at the two ends of the magnetic rod bracket 2 are closed, and the magnetic field intensity at the two ends can be smoothly attenuated. The magnetic lines of force corresponding to the end surface of the target material are uniformly distributed, so that the magnetic field intensity on the surface of the target material is uniform. The uniform magnetic field intensity enables the etching of the target material at the end part to be consistent with the etching of the target material in the middle section, namely the effective coating area, and the phenomenon that the utilization rate of the target material is reduced due to the fact that the etching groove is too deep caused by the serious etching of the end part of the target material because the magnetic field at the end part is too strong can be avoided.

In the embodiment, in order to further adjust the magnetic field intensity at the end part and match the adjustment of the length of the effective coating area, the inclination angle of the encircling path relative to the length direction of the magnetic rod bracket 2 is 15-60 degrees.

In one embodiment, the inclination angle of the encircling path is 25-45 degrees.

As shown in fig. 5, the magnet 3 is installed on the magnet holder 2, and the magnet is protruded toward the magnet, and has a curve with a certain radian or a trapezoid shape. The magnets 3 in the central row are arranged at the highest position of the convex position, and the magnets 3 in the two side rows are symmetrically distributed on two sides of the position, slightly lower than the magnets 3, of the central row. The magnet surfaces of the central row and the two side rows are made to present a certain radian, so that the distance from the surface of each magnet 3 to the target is different, the magnetic field intensity corresponding to the target is different, and the magnetic field intensity is adjusted by adjusting the arching degree of the magnet rod bracket 2 on one surface of the magnet 3.

In this embodiment, the magnet bar holder 2 and the magnet 3 are each provided with a mounting hole for fixing the same by engaging with a screw. Other fastening methods may be used in other embodiments.

In the present embodiment, the bar magnet holder 2 is made of a non-magnetic material.

Above-mentioned rotary cathode bar magnet 1 that magnetron sputtering used, through to 5 peripheral groups 51 of tip magnet along 2 length direction both ends of bar magnet support, the magnet that is in both sides limit row by middle part magnet 4 respectively draws close to the centre along the straight line and crosses, and the magnetic field intensity at both ends is effectively attenuated like this for with the magnetic field intensity evenly distributed that 2 middle part magnet 3 of bar magnet support produced, thereby under the condition of not shortening effective coating area length, improve target effective utilization.

As shown in fig. 6 to 9, the present application also provides a magnetron 7 including a cylindrical target 8, the inside of the target 8 is used as a mounting chamber, and the rotary cathode magnetic rod 1 for magnetron sputtering is arranged in the mounting chamber.

In the embodiment, a plurality of support frames 9 are arranged in the mounting chamber at intervals along the axial direction of the target material 8, and cooling water pipes 10 extending along the axial direction of the target material 8 are fixed on the plurality of support frames 9; the bottom surface of the magnetic rod bracket 2 is connected with a cooling water pipe 10 through an interval adjusting seat 11, and the top surface of the magnetic rod bracket 2 is also buckled with a sealing cover 12 for shielding each magnet 3.

In this embodiment, the magnetron sputtering coating needs to work under a high power, so that the whole magnetron 7 will be in a high temperature state, and then the magnet 3 in the inside needs to be kept at a certain stability and will keep a certain magnetism to ensure that a preset magnetic field strength is reached. Therefore, a cooling water pipe 10 is installed inside the magnetron 7 along the axial direction of the target 8, and the inside thereof is cooled by circulating cold water.

Because the magnetism of each magnet 3 can not guarantee that the magnetic field generated by each magnet is the same as that generated when the cathode magnetic steel works, the generated magnetic fields can not be uniformly distributed. In order to solve the problem, an adjusting seat 11 for adjusting the specific distance between the magnet 3 and the surface of the target material 8 is further installed on the bottom surface of the magnetic rod bracket 2. The distance between each magnet 3 and the surface of the corresponding target 8 is adjusted to change the intensity of the magnetic field on the target 8, so that the magnetic field intensity in the coating effective area can be consistent.

Since the magnetron 7 is internally provided with the cooling water pipe 10, there is a risk that cold water therein overflows and the magnet 3 will affect its magnetism upon contact with water. In order to solve this problem, a sealing cover 12 for shielding each magnet 3 is provided on the top surface of the magnet 3, and the normal operation of each magnet 3 is not affected even if water in the cooling water pipe 10 overflows in a completely sealed state of the magnet 3.

In this embodiment, the support frame 9 is a guide ring, and after the magnetron 7 is installed, a certain gap is formed between the outer wall of the guide ring and the inner wall of the target, and the gap is small, so that the guide ring and the connecting piece 14 are centered.

Furthermore, the support frame 9 is provided with a bayonet 91, the cooling water pipe 10 is a single pipe and is embedded in the bayonet 91, and a fastening piece 13 fixed with the cooling water pipe 10 is installed on the side wall of the bayonet.

In this embodiment, the inner wall of the bayonet 91 is matched with the outer peripheral wall of the cooling water pipe 10 to play a role of positioning.

In one embodiment, the fastening member 13 penetrates the cooling water pipe 10 along the radial gap of the cooling water pipe 10.

Specifically, fastener 13 is the screw rod, has seted up on the double-phase opposite side wall of support frame 9 back to bayonet socket 91 and has dodged the hole for the screw rod runs through support frame 9 to and set up condenser tube 10 at bayonet socket 91 inner wall, and the one end of screw rod head offsets with a support frame 9 lateral wall, has the screw thread on the screw other end periphery wall through further fastening condenser tube 10 with the nut cooperation. Wherein, the screw part penetrating through the cooling water pipe 10 is in sealing fit with the cooling water pipe 10.

In this embodiment, the outer edge of the supporting frame 9 facing away from the bayonet 91 abuts against the inner wall of the installation chamber, the rotary cathode magnetic rod 1 faces away from the bayonet 91, and the magnet 3 on the rotary cathode magnetic rod 1 faces the inner wall of the installation chamber.

Specifically, an avoiding groove 92 is further formed on one side of the supporting frame 9 facing away from the bayonet 91 to accommodate the rotary cathode magnetic rod 1. Wherein, the bottom surface of the magnetic rod bracket 2 of the rotary cathode magnetic rod 1 faces the avoiding groove 92, and the top surface of the magnetic rod bracket 2 is provided with a magnet 3 facing the inner wall of the installation chamber.

As shown in fig. 9 to 10, the spacing adjustment base 11 includes: a U-shaped holder 111, wherein the cooling water pipe 10 is clamped and fixed in the U-shaped holder 111; two adjusting blocks 112 respectively fixed on two sides of the opening of the U-shaped support 111; and the adjusting screw 113 acts between each adjusting block 112 and the bottom surface of the magnetic rod bracket 2 to change the distance between the magnet 3 and the target 8 on the magnetic rod bracket 2.

In this embodiment, two connecting portions are sequentially disposed on two sides of the opening of the U-shaped bracket 111 along the axial direction of the cooling water pipe 10, and each connecting portion is provided with a connecting hole, and each connecting hole is respectively matched with a bolt to fix two sides of the opening of the U-shaped bracket 111 to the bottom surface of a corresponding adjusting block 112.

In this embodiment, the bottom surfaces of the magnetic rod supports 2 are provided with a pair of spacers 114, and the adjusting screws 113 at two sides of the opening of the U-shaped holder 111 abut against and/or are in threaded engagement with the corresponding spacers 114.

Furthermore, the two cushion blocks 114 in the interval adjusting seat 11 respectively correspond to the two adjusting blocks 112, and are respectively disposed on the top surfaces of the two corresponding adjusting blocks 112, and two ends of the adjusting blocks 112 along the length direction thereof are respectively provided with a through hole, so that one end of the adjusting screw 113 can sequentially penetrate through the adjusting blocks 112 and be connected with the cushion blocks 114. The distance between the adjusting block 112 and the corresponding cushion block 114 is adjusted by using the adjusting screw 113, so as to adjust the distance between the top surface of the magnetic rod bracket 2 and the target 8, and finally achieve the aim of adjusting the magnetic field intensity.

As shown in fig. 8, a plurality of distance adjusting seats 11 are arranged along the length direction of the target 8, and each distance adjusting seat 11 can be adjusted according to the actual magnetic field intensity distribution, so that the magnetic field intensity on the surface of the target 8 at a plurality of positions is adjusted, and finally, the magnetic field intensity on the surface of the target 8 is uniformly distributed in the whole effective film area.

The adjusting screw 113 and the cushion block 114 can be connected in an abutting manner or in a thread fit manner.

Specifically, a hole is formed in the cushion block 114 and is fixed to the bottom surface of the magnetic rod bracket 2 through matching with a bolt.

In this embodiment, the two opposite side outer walls of the cooling water pipe 10 are provided with positioning slots, and the two adjusting blocks 112 are respectively matched with the corresponding positioning slots. Therefore, the cooling water pipe 10 is further positioned and fastened, the outer wall of the cooling water pipe 10 is more closely matched with the opposite inner walls of the two adjusting blocks 112, and unnecessary friction caused by relative movement is avoided in the sputtering coating process.

In this embodiment, because the screw rod is clearance fit with condenser tube 10, does not have good sealing effect, so water in condenser tube 10 will overflow, in order to make the water that magnet 3 can not contact, the caulking groove has been seted up at the periphery of magnet 3 at bar magnet support 2 top surface, is provided with sealed pad 53 in the caulking groove, and the bottom of sealed cowling 12 compresses tightly sealed pad 53, plays sealed effect, and the water in the isolated condenser tube 10 overflows and contacts magnet 3 and causes the damage to magnet 3.

In the present embodiment, the seal cover 12 includes: a housing 121 extending axially along the target 8 to a respective end of the pole piece 31; and two seal heads 72 which are hermetically matched at the ends of the shell 121 and the pole piece 31.

Further, the housing 121 of the sealing cover 12 is arched upward, and the curvature of the housing is matched with the curvature of the top surface of the magnetic rod support 2. The outer contour of the outer wall of the housing 121 and the outer side wall of the support frame 9 is adapted to the inner wall of the mounting chamber.

In this embodiment, the two opposite sides of the housing 121 are provided with flanges 1211, and the flanges 1211 press the sealing gaskets 53, and the flanges 1211 are fixed to the top surface of the magnetic rod bracket 2 by screws.

In the magnetron 7 for magnetron sputtering, the top surface of the magnetic rod bracket 2 and the periphery of the magnet 3 are provided with the caulking grooves, and the sealing gaskets 53 which are in sealing fit with the bottom of the sealing cover 12 are arranged in the caulking grooves, so that the magnet arranged in the sealing area cannot be damaged due to overflow of water in the external cooling water pipe 10. And a plurality of spacing adjusting seats 11 are arranged on the bottom surface of the magnetic rod bracket 2 along the length direction of the target material 8 so as to adjust the spacing between the magnet 3 and the target material 8, thereby adjusting the magnetic field intensity on the surface of the target material 8.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The rotary cathode magnetic rod for magnetron sputtering comprises a magnetic rod bracket and magnets fixed on the surface of the magnetic rod bracket, wherein the magnets comprise a middle magnet and end magnets along the length direction of the magnetic rod bracket;

the end magnet includes:

2. The rotating cathode magnetic rod according to claim 1, wherein the middle magnets in the same row in the length direction of the magnetic rod bracket are located at the middle of the whole magnet, and the adjacent ends of the middle magnets are provided with a plurality of magnets arranged at intervals.

3. The rotating cathode bar magnet of claim 1, wherein the middle group has at least two magnets, and each magnet of the middle group has a gradually decreasing size and a gradually decreasing magnetic field extending toward the end of the bar magnet holder.

4. A rotary cathode magnetic rod according to claim 3 wherein the middle group is two magnets.

5. A rotary cathode magnetic rod as claimed in claim 1 wherein the peripheral group comprises two enclosure units on either side of the central group and end magnets aligned with the central group, the two enclosure units extending towards the ends of the rod holder and meeting at the end magnets.

6. The rotating cathode magnetic rod according to claim 5, wherein the two enclosure units are symmetrically arranged, and the end point magnet is arranged in a staggered manner with the nearest magnet in each enclosure unit in the length direction of the magnetic rod bracket.

7. The rotating cathode magnetic rod according to claim 6, wherein each of the enclosure units comprises a plurality of magnets arranged along an enclosure path, and the magnets of the same enclosure unit are the same or different in size.

8. The rotating cathode magnetic rod according to claim 7, wherein the angle of inclination of the enclosed path is 15-60 degrees with respect to the length direction of the magnetic rod support.

9. The rotating cathode bar magnet of claim 8, wherein the enclosed path is inclined at an angle of 25-45 degrees.

10. Magnetron, including a cylindrical target material, the inside of which is used as a mounting chamber, characterized in that a rotary cathode magnetic rod for magnetron sputtering according to any one of claims 1 to 9 is arranged in the mounting chamber.