Secondary shield for ion source

Abstract

The utility model discloses a secondary shield for an ion source, which relates to the field of optical coating, aims to solve the problem that the length of an insulating gas needle is increased and the compactness of the internal structure of equipment is influenced, and is characterized in that a gas outlet pipe is a Tesla valve of which a gas flow outlet is aligned with a discharge chamber, so that the gas needle body is not increased in length, and meanwhile, the gas needle body is prevented from being damaged. Ion gas is effectively prevented from entering a gas pipeline, the gas supply effect is more stable, the whole equipment is more compact, and meanwhile the size is further reduced conveniently.

Description

Technical Field

[0001] The utility model relates to the technical field of optical coating, in particular to a secondary shield for an ion source. Background Art

[0002] The radio frequency ion source is an ion source with a wide range of applications, and can be used in ion beam sputtering, ion beam etching, surface treatment, and assisted deposition. The radio frequency ion source generates plasma in the discharge chamber through the principle of inductive coupling, and the ion optical system forms an ion beam. When introducing the working gas into the discharge chamber of the radio frequency ion source, it is usually first processed by an insulating gas needle. The insulating gas needle allows the working gas to enter the discharge chamber in a laminar flow, stably and evenly, to improve the uniformity of the plasma. At present, the insulating gas needles on the market, the electromagnetic waves generated by the radio frequency coil are prone to gas discharge inside the insulating gas needle, resulting in unstable gas supply, affecting the working stability of the radio frequency ion source or even extinguishing it.

[0003] There is an insulated gas needle and radio frequency ion source with patent number CN220963234U, comprising: an air inlet pipe, an air needle body and an air outlet pipe connected in series; wherein the air inlet pipe and the air outlet pipe are respectively connected to the two ends of the air needle body; the air needle body comprises: an air guide, an insulating part, a first electrode, a second electrode and an electromagnetic shielding layer; the insulating part wraps the air guide, and the first electrode and the second electrode are respectively arranged at the two ends of the air guide; the electromagnetic shielding layer is covered on the outside of the insulating part; the first electrode and the second electrode form an electric field; in the working state, the working gas enters the air guide from the air inlet pipe, and is output to the discharge chamber of the radio frequency ion source by the air outlet pipe; this technical solution can block the electromagnetic waves generated by the radio frequency coil from passing through the gas flow area, avoid gas discharge of the working gas inside the insulated gas needle, improve the anti-interference ability of the insulated gas needle, and ensure stable gas supply.

[0004] The above-mentioned existing technical solutions have the following defects: the gas needle body is designed as an extended structure, so as to better suppress the plasma in the discharge chamber from diffusing into the interior of the insulating gas needle. The insulating gas needle as a whole lacks means to prevent plasma backflow, which lengthens the length of the insulating gas needle and affects the compactness of the internal structure of the equipment. Utility Model Content

[0005] The utility model aims to provide a secondary shield for an ion source.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] It includes an air inlet pipe, an air needle body and an air outlet pipe connected in series, the air inlet pipe and the air outlet pipe are respectively connected to the two ends of the air needle body, the air needle body includes an air guide member with two ends connected to the air inlet pipe and the air outlet pipe, the end of the air outlet pipe is connected to a discharge chamber, a radio frequency coil is fixedly provided on the bottom wall of the discharge chamber, the radio frequency coil is externally connected to a radio frequency power supply, the outer wall of the air guide member is wrapped with a first insulating layer, the end of the air guide member close to the air outlet pipe is covered with the first insulating layer and is provided with a first electrode, the outer wall of the air inlet pipe close to the radio frequency power supply is fixedly installed with a second electrode, the air guide member is wrapped with the first insulating layer and the first electromagnetic shielding cover, the air outlet pipe is a Tesla valve with the air flow outlet aligned with the discharge chamber, and the second electrode is grounded.

[0008] By adopting the above technical solution, during operation, the working gas enters the gas guide from the air inlet pipe and is output to the discharge chamber of the radio frequency ion source through the air outlet pipe, thereby blocking the electromagnetic waves generated by the radio frequency coil from passing through the gas guide, and avoiding gas discharge of the working gas inside the gas guide. The air outlet pipe is a Tesla valve with the function of preventing fluid backflow. When the ion gas flows back in the air outlet pipe, the ion flow deflected by the Tesla valve branch structure will offset the ion flow of the main channel to achieve a backflow prevention effect. Without increasing the length of the gas needle body, it effectively prevents the ion gas from entering the gas pipeline, making the gas supply more stable.

[0009] Furthermore, a third grounded electrode is fixedly mounted on the outer wall of the air inlet pipe near one end of the radio frequency power supply, and a second insulating layer is provided on the outer wall of the air outlet pipe.

[0010] By adopting the above technical solution, an electric field is formed between the charged first electrode and the grounded second electrode and third electrode.

[0011] Furthermore, the outer wall of the air outlet pipe is wrapped with a second insulating layer and provided with a second electromagnetic shielding cover.

[0012] By adopting the above technical solution, the first electromagnetic shielding cover is combined with the second electromagnetic shielding cover to secondary shield external interference, which has a good electromagnetic shielding effect. The gas is accelerated in the gas guide and then transported through the Tesla valve to ensure stable gas transportation.

[0013] In summary, the beneficial technical effects of the present invention are:

[0014] 1. The Tesla valve is used, which effectively prevents ion gas from entering the gas pipeline without increasing the length of the gas needle body, making the gas supply more stable;

[0015] 2. A third electrode, a second insulating layer and a second electromagnetic shielding cover are used to produce a good electromagnetic shielding effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The accompanying drawings are used to provide a further understanding of the present invention and constitute part of the specification, but do not constitute a limitation of the present invention. In the accompanying drawings:

[0017] Figure 1 It is a schematic cross-sectional view of the overall structure of the utility model.

[0018] In the figure, 1. air inlet pipe; 2. air needle body; 21. first insulating layer; 22. first electromagnetic shielding cover; 3. air outlet pipe; 31. second insulating layer; 32. second electromagnetic shielding cover; 4. discharge chamber; 41. radio frequency coil; 5. first electrode; 6. second electrode; 7. third electrode. DETAILED DESCRIPTION

[0019] The present invention will be described in further detail below with reference to the accompanying drawings.

[0020] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0021] See also Figure 1 , this utility model provides a technical solution:

[0022] It includes an air inlet pipe 1, an air needle body 2 and an air outlet pipe 3 connected in series, the air inlet pipe 1 and the air outlet pipe 3 are respectively connected to the two ends of the air needle body 2, the air needle body 2 includes an air guide member whose two ends are connected to the air inlet pipe 1 and the air outlet pipe 3, the end of the air outlet pipe 3 is connected to a discharge chamber 4, a radio frequency coil 41 is fixedly provided on the bottom wall of the discharge chamber 4, the radio frequency coil 41 is externally connected to a radio frequency power supply, the outer wall of the air guide member is wrapped with a first insulating layer 21, the end of the air guide member close to the air outlet pipe 3 is covered with the first insulating layer 21 and is provided with a first electrode 5, the outer wall of the air inlet pipe 1 close to the radio frequency power supply is fixedly installed with a second electrode 6, the air guide member is wrapped with the first insulating layer 21 and the first electromagnetic shielding cover 22, The outlet pipe 3 is a Tesla valve with the air flow outlet aligned with the discharge chamber 4, and the second electrode 6 is grounded. During operation, the working gas enters the gas guide from the air inlet pipe 1 and is output to the discharge chamber 4 of the RF ion source by the outlet pipe 3, blocking the electromagnetic waves generated by the RF coil 41 from passing through the gas guide, thereby avoiding gas discharge of the working gas inside the gas guide. The outlet pipe 3 is a Tesla valve with the function of preventing fluid backflow. When the ion gas flows back in the outlet pipe 3, the ion flow deflected by the Tesla valve branch structure will offset the main channel ion flow to achieve a backflow prevention effect. Without increasing the length of the gas needle body 2, it effectively prevents the ion gas from entering the gas pipeline, making the gas supply more stable.

[0023] A grounded third electrode 7 is fixedly installed on the outer wall of the air inlet pipe 1 near the RF power supply, and a second insulating layer 31 is provided on the outer wall of the air outlet pipe 3. An electric field is formed between the charged first electrode 5 and the grounded second and third electrodes 6 and 7.

[0024] The outer wall of the outlet pipe 3 is wrapped with a second insulating layer 31 and provided with a second electromagnetic shield 32. The first electromagnetic shield 22 combined with the second electromagnetic shield 32 provide secondary shielding against external interference, achieving excellent electromagnetic shielding effectiveness. Gas is accelerated in the air guide and then transported through the Tesla valve, ensuring stable gas transport.

[0025] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that includes a list of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus.

[0026] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art will be able to modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein with equivalents. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included within the scope of protection of the present invention.

Claims

1. A secondary shield for an ion source, characterized in that: The invention comprises an air inlet pipe (1), an air needle body (2) and an air outlet pipe (3) connected in series, wherein the air inlet pipe (1) and the air outlet pipe (3) are respectively connected to two ends of the air needle body (2), the air needle body (2) comprises an air guide member whose two ends are connected to the air inlet pipe (1) and the air outlet pipe (3), the end of the air outlet pipe (3) is connected to a discharge chamber (4), a radio frequency coil (41) is fixedly provided on the bottom wall of the discharge chamber (4), and the radio frequency coil (41) is externally connected to a radio frequency power supply, the outer wall of the air guide member is wrapped with a first insulating layer (21), the end of the air guide member close to the air outlet pipe (3) is covered with the first insulating layer (21) and is provided with a first electrode (5), the outer wall of the air inlet pipe (1) close to the radio frequency power supply is fixedly installed with a second electrode (6), the air guide member is wrapped with a first electromagnetic shielding cover (22) of the first insulating layer (21), the air outlet pipe (3) is a Tesla valve with an air flow outlet aligned with the discharge chamber (4), and the second electrode (6) is grounded.

2. The secondary shield for an ion source according to claim 1, characterized in that: A third grounded electrode (7) is fixedly mounted on the outer wall of the air inlet pipe (1) near one end of the radio frequency power supply, and a second insulating layer (31) is provided on the outer wall of the air outlet pipe (3).

3. The secondary shield for an ion source according to claim 2, characterized in that: The outer wall of the air outlet pipe (3) is wrapped with a second insulating layer (31) and is provided with a second electromagnetic shielding cover (32).

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