Vacuum metal evaporation output window capable of eliminating backscattered electrons and secondary electrons

Abstract

The utility model discloses an output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons, metal steam generated by melting of a target material in a crucible rises and is diffused to a coating substrate through a window body of the conveying window to be cooled and deposited to form a film, the conveying window comprises a frame, two opposite sides of the frame are provided with permanent magnet magnetic circuits, and the permanent magnet magnetic circuits are connected with the conveying window. A window for metal steam to rise is arranged between the two permanent magnet magnetic circuits; the permanent magnet magnetic circuit comprises at least two magnet yokes, a permanent magnet arranged between the two magnet yokes and a partition plate, and pole shoes are arranged at the ends, away from the frame and located on the same horizontal plane with the partition plate, of the magnet yokes; the two permanent magnet magnetic circuits are circumferentially and symmetrically distributed according to the center of the output window, and the pole shoes of the magnetic circuits on the two sides are arranged in a staggered manner, so that the bombardment of back scattering electrons and secondary electrons on a coating substrate through the output window is greatly reduced, and the molecular arrangement structure of the substrate is not damaged; therefore, the tensile mechanical strength of the base material is not obviously reduced.

Description

Technical Field

[0001] The utility model relates to the field of electron beam vacuum metal coating, in particular to an output window for vacuum metal evaporation which can eliminate backscattered electrons and secondary electrons. Background Art

[0002] Vacuum coating technology is widely used in industries such as plastic packaging for electronic components, decorative film materials, thin film capacitors, and current collectors for new energy batteries. Electron beam coating technology has significant advantages in terms of performance, environmental protection, and efficiency. Existing electron beam vacuum coating technology generally uses an electron gun to generate a high-energy electron beam to bombard the target material, causing the target material in the crucible to heat and melt and generate metal vapor. The metal vapor passes through an output window and then cools and deposits on the plastic coating substrate to form a film. The thickness of the coating substrate is generally in the micron level and has low mechanical strength. When the electron beam bombards the target material, strong backscattered electrons and secondary electrons are generated. These electrons will bombard the coating substrate through the output window, destroying the molecular structure of part of the substrate, resulting in a decrease in tensile mechanical strength, affecting the winding speed of the subsequent coating processing, and causing a decrease in service life and safety factor. The problem of reduced mechanical strength of the coating caused by electron bombardment makes it a significant disadvantage when competing with water-based electroplating coating technology. Utility Model Content

[0003] In order to solve the above technical problems, the utility model provides an output window for vacuum metal evaporation that can eliminate backscattered electrons and secondary electrons, greatly reducing the bombardment of backscattered electrons and secondary electrons on the coated substrate through the output window, so that the molecular arrangement structure of the substrate will not be destroyed, thereby ensuring that the tensile mechanical strength of the substrate will not decrease significantly.

[0004] The technical solution of the utility model is: an output window for vacuum metal evaporation that can eliminate backscattered electrons and secondary electrons. The metal vapor generated by the melting of the target material in the crucible rises and diffuses through the window of the delivery window to the coating substrate to cool and deposit into a film. The delivery window includes a frame, and permanent magnetic circuits are provided on opposite sides of the frame. A window for the metal vapor to rise is provided between the two permanent magnetic circuits.

[0005] The permanent magnetic circuit includes at least two magnetic yokes, a permanent magnet and a partition provided between the two magnetic yokes, and one end of the magnetic yoke away from the frame and on the same horizontal plane as the partition is a pole shoe;

[0006] The two permanent magnetic circuits are symmetrically distributed around the center of the output window, and the pole shoes of the magnetic circuits on both sides are staggered.

[0007] Furthermore, one end of the permanent magnet abuts against the inner wall of the frame, and the other end of the permanent magnet abuts against the partition.

[0008] Furthermore, multiple groups of permanent magnetic circuits are provided on the same side, and the multiple groups of permanent magnetic circuits are arranged along the length direction of the frame.

[0009] Furthermore, the magnetic polarities of the pole shoes of the multiple groups of permanent magnetic circuits are arranged in an alternating manner.

[0010] Furthermore, the polarities of the pole shoes on the same side are S pole and N pole in sequence, and the S pole and N pole are alternately arranged on the same side.

[0011] Furthermore, the distance between pole shoes with opposite magnetic polarity is shorter than the distance between pole shoes with the same magnetic polarity, and the distance between two pole shoes on the same side is the same as the distance between two pole shoes on the other side.

[0012] Furthermore, an electron absorption baffle is provided above the output window.

[0013] Furthermore, the frame is a non-magnetic frame.

[0014] Furthermore, the partition is a non-magnetic partition.

[0015] The beneficial technical effects of the utility model are:

[0016] Within a rectangular, non-magnetic frame, a double-sided magnetic field structure is staggered along the length of the window. The pole shoes in the magnetic circuits are asymmetrically distributed; the distance between pole shoes of opposite magnetic polarity is shorter than that between pole shoes of the same polarity. The distance between two pole shoes on one side is comparable to the distance between two pole shoes of opposite polarity on the other side. This arrangement creates a unique permanent magnetic field that significantly reduces the bombardment of the coating substrate by backscattered and secondary electrons through the output window, preventing damage to the substrate's molecular structure and thus ensuring no significant loss of tensile strength. This, in turn, increases the speed and efficiency of the vacuum coating process, improving the quality and safety of the finished coating. This technology gives electron beam metal vacuum evaporation an edge over water-based electroplating.

[0017] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention and to implement it according to the contents of the specification, the following is a detailed description of the preferred embodiments of the present invention in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 This is a schematic diagram of the coating mechanism;

[0019] Figure 2 This is a schematic structural diagram of the output window of the utility model;

[0020] Figure 3 This is a schematic diagram of the magnetic field distribution of the present utility model.

[0021] The accompanying drawings are:

[0022] 1. Crucible; 2. Target; 3. Electron gun; 31. Electron beam; 4. Electrons; 5. Output window; 51. Frame; 52. Permanent magnet; 53. Partition; 54. Magnetic yoke 1; 55. Magnetic yoke 2; 56. Magnetic yoke 3; 57. Pole shoe; 6. Electron absorption baffle; 7. Winding drum; 71. Coating substrate. DETAILED DESCRIPTION

[0023] In order to more clearly understand the technical means of the present invention and implement it according to the contents of the specification, the specific implementation methods of the present invention are further described in detail below in conjunction with the drawings and examples. The following examples are used to illustrate the present invention but are not used to limit the scope of the present invention.

[0024] It should be noted that the terms "first," "second," and the like in the specification and claims of this application and the accompanying drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, for the purposes of describing the embodiments of the present application herein.

[0025] In the description of the present utility model, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. indicate orientations or positional relationships based on the descriptions in the embodiments and shown in the accompanying drawings, or are the orientations or positional relationships in which the utility model product is usually placed when in use. They are only for the convenience of describing the present utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they cannot be understood as a limitation on the present utility model.

[0026] Conventional electron beam vacuum coating mechanisms such as Figure 1 As shown, its working principle is: all mechanisms work in a vacuum environment, the coating substrate 71 is close to the winding drum 7 and is driven by the winding drum 7 to move for evaporation. The electron gun 3 emits an electron beam 31 to bombard the target material 2 in the crucible 1, causing the target material 2 to melt and evaporate into metal vapor. The metal vapor rises and diffuses, and diffuses through the window of the output window 5 to the coating substrate 71, where it cools and deposits into a film. When the electron beam 31 bombards the target material 2, a large number of backscattered electrons 4 and secondary electrons 4 are generated. The electrons 4 will be scattered in disordered directions in the cavity, and some of the electrons 4 will pass through the output window 5 and bombard the coating substrate 71. The energy of the backscattered electrons 4 is very high, and the bombardment will cause the molecular arrangement structure of the coating substrate 71 to deteriorate, resulting in a significant decrease in tensile strength.

[0027] In order to solve the above technical problems, the utility model specially designs a special permanent magnetic field around the output window 5. Under the action of this magnetic field, the electrons 4 passing through the output window 5 will be deflected under the action of the Lorentz magnetic force. After deflection, the electrons 4 will turn and bombard the outside of the coating drum, so that the bombardment of the coating substrate 71 by the electrons 4 is greatly reduced, the original molecular arrangement structure is maintained, and the tensile mechanical strength will not decrease significantly after coating.

[0028] like Figure 2 As shown, the present invention specifically relates to an output window 5 for vacuum metal evaporation that can eliminate backscattered electrons 4 and secondary electrons 4. The metal vapor generated by the melting of the target material 2 in the crucible 1 rises and diffuses through the window of the delivery window to the coating substrate 71, where it is cooled and deposited into a film. The delivery window includes a frame 51. Permanent magnetic circuits are provided on opposite sides of the frame 51. A window for the metal vapor to rise is provided between the two permanent magnetic circuits.

[0029] The permanent magnetic circuit includes at least two magnetic yokes, a permanent magnet 52 and a partition 53 disposed between the two magnetic yokes. One end of the magnetic yoke away from the frame 51 and on the same horizontal plane as the partition 53 is a pole shoe 57.

[0030] The two permanent magnetic circuits are symmetrically distributed around the center of the output window 5 , and the pole shoes 57 of the magnetic circuits on both sides are staggered.

[0031] The frame 51 is a non-magnetic frame 51 , and the partition 53 is a non-magnetic partition 53 .

[0032] The frame 51 is made of a non-magnetic material, and the partition 53 is also made of a non-magnetic metal such as aluminum or copper or alloys thereof.

[0033] Two rows of permanent magnetic circuits are arranged in the rectangular frame 51 . The two rows of permanent magnetic circuits are symmetrically distributed around the center of the output window 5 . The magnetic circuits are composed of a yoke, a permanent magnet 52 and a partition 53 .

[0034] One end of the permanent magnet 52 abuts against the inner wall of the frame 51 , and the other end of the permanent magnet 52 abuts against the partition 53 .

[0035] The yoke is located on opposite sides of the permanent magnet 52 and is used to transmit the magnetic force of the permanent magnet 52. One end of the permanent magnet 52 abuts against the frame 51, and the other end of the permanent magnet 52 abuts against the partition 53, so that a specific magnetic field is formed through the obstruction of the partition 53.

[0036] There are multiple groups of permanent magnetic circuits on the same side, and the multiple groups of permanent magnetic circuits are arranged along the length direction of the frame 51.

[0037] In order to match the setting of multiple sets of permanent magnetic circuits, multiple identical yokes are provided, and the multiple yokes can be divided into three types: yoke one 54, yoke two 55 and yoke three 56, wherein yoke one 54 and yoke three 56 are located at opposite ends of the magnetic circuit on the same side and there is only one of each, and yoke two 55 is located in the middle of the magnetic circuit on the same side and there are multiple yokes.

[0038] In addition, the structures of yoke 1 54, yoke 2 55 and yoke 3 56 are the same but the shapes are different. They have the same function in this embodiment, but the different shapes ensure that the shape structure of the permanent magnetic circuit on the same side is a regular rectangular parallelepiped; the shape structure of the permanent magnetic circuit on the other side is also the same, thereby creating a special double-sided permanent magnetic field.

[0039] The magnetic polarities of the multiple groups of pole shoes 57 of the permanent magnetic circuit are staggered.

[0040] The polarities of the pole shoes 57 on the same side are S pole and N pole in sequence, and the S pole and N pole are alternately arranged on the same side.

[0041] The distance between the pole shoes 57 with opposite magnetic polarity is shorter than the distance between the pole shoes 57 with the same magnetic polarity, and the distance between the two pole shoes 57 on the same side is the same as the distance between the two pole shoes 57 on the other side, making the distribution of the magnetic field more conducive to the deflection of backscattered electrons 4 and secondary electrons 4 to the two sides, thereby minimizing the deflection blind area.

[0042] In the structure described above, the equipotential surface of the magnetic field synthesis is oblique, and the transport window has a certain thickness. When the electron 4 passes through the transport window, its speed in the thickness direction remains unchanged, while it moves gradually in the deflection direction.

[0043] When backscattered electrons 4 and secondary electrons 4 pass through output window 5, they are driven by the Lorentz force under the influence of the magnetic field, deflecting them in a direction perpendicular to both their direction of motion and the direction of the magnetic field. Depending on the arrangement of the magnetic field, electrons 4 may be deflected to the upper left or lower right while passing through output window 5. The deflection radius varies depending on the strength of the magnetic field and their own velocity. Ultimately, the majority of electrons 4 are directed toward the electron absorption baffle 4 behind output window 5, protecting the coated substrate 71.

[0044] An electron absorption baffle 4 is provided above the output window 5 .

[0045] The above embodiments are only specific implementation methods of the present invention, which are used to illustrate the technical solutions of the present invention rather than to limit them. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in this field should understand that any technician familiar with this technical field can still modify the technical solutions recorded in the above embodiments within the technical scope disclosed by the present invention, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. An output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons, wherein the metal vapor generated by the melting of the target material (2) in the crucible (1) rises and diffuses through the window of the delivery window to the coating substrate (71) for cooling and deposition to form a film, characterized in that: The conveying window comprises a frame (51), two opposite sides of the frame (51) are provided with permanent magnetic circuits, and a window for the metal vapor to rise is provided between the two permanent magnetic circuits; The permanent magnetic circuit includes at least two magnetic yokes, a permanent magnet (52) and a partition (53) disposed between the two magnetic yokes, and one end of the magnetic yoke that is away from the frame (51) and is in the same horizontal plane as the partition (53) is a pole shoe (57); The two permanent magnetic circuits are symmetrically distributed around the center of the output window (5), and the pole shoes (57) of the magnetic circuits on both sides are staggered.

2. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 1, characterized in that: One end of the permanent magnet (52) abuts against the inner wall of the frame (51), and the other end of the permanent magnet (52) abuts against the partition (53).

3. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 1, characterized in that: There are multiple groups of permanent magnetic circuits on the same side, and the multiple groups of permanent magnetic circuits are arranged along the length direction of the frame (51).

4. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 3, characterized in that: The magnetic polarities of the pole shoes (57) of the plurality of groups of permanent magnetic circuits are arranged in a staggered manner.

5. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 4, characterized in that: The polarities of the pole shoes (57) on the same side are S pole and N pole in sequence, and the S pole and N pole are alternately arranged on the same side.

6. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 5, characterized in that: The distance between pole shoes (57) with opposite magnetic polarities is shorter than the distance between pole shoes (57) with the same magnetic polarity, and the distance between two pole shoes (57) on the same side is the same as the distance between two pole shoes (57) on the other side.

7. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 1, characterized in that: An electron (4) absorbing baffle is provided above the output window (5).

8. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 1, characterized in that: The frame (51) is a non-magnetic frame (51).

9. The output window for vacuum metal evaporation capable of eliminating backscattered electrons and secondary electrons according to claim 1, characterized in that: The partition (53) is a non-magnetic partition (53).

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