A miniature ion source for plasma timing ignition

Abstract

The invention discloses a miniature ion source for plasma timing ignition, comprising a base, an anode nested on the base, a cathode installed on one side of the anode, a labyrinth isolation ceramic layer installed between the anode and the cathode, an insulating outer cover sleeved on the outer wall of the cathode and sealedly connected to the base, the insulating outer cover is sealedly connected to the cathode, the interior of the cathode is a vacuum chamber, one side of the cathode is provided with a gas injection hole connected to the vacuum chamber, a first plasma extraction hole is provided on the labyrinth isolation ceramic layer, a second plasma extraction hole is provided on the anode, the size of the second plasma extraction hole is slightly smaller than the first plasma extraction hole, a middle hole is provided on the base, the discharge electrode material of the cathode is metal hafnium, metal tantalum or metal titanium, and the micro-ion source has the advantages of small sputtering yield, rapid ignition, accurate and stable ignition timing, simple and compact structure, waterproof function and long service life.

Description

Technical Field

[0001] The invention relates to the field of ion generators, in particular to a micro ion source for plasma timing ignition. Background Art

[0002] The gas discharge caused by the existing radio frequency (microwave) plasma generation has uncertainty in the start time, and even the phenomenon of plasma failure occurs. Therefore, it is usually necessary to inject charged particles into the working gas in advance to ensure the timely ignition and start of the plasma. Traditional timing ignition source devices include hot cathode emission, ultraviolet lamps and laser irradiation.

[0003] The electric heating filament of the hot cathode emission method is exposed to the plasma during use, and has the disadvantages of rapid wear and tear and short life; the ultraviolet lamp is used outside the plasma, but it is prone to changes, and slight changes will cause the timing jitter of the ignition current, resulting in unsuccessful ignition, and there is still a technical problem of poor ignition stability; the laser device has the disadvantages of being large in size and expensive.

[0004] In addition, the cathode material of the general ignition source is metallic copper or metallic molybdenum. There are two problems with these two metals as cathode materials: first, the ignition time is long and the ignition time control accuracy is low; second, under the bombardment of hydrogen, the cathode sputtering output is large, and the sputtered metal accumulates between the anode and cathode, causing a short circuit and resulting in failure of the ignition source. Summary of the invention

[0005] The purpose of the present invention is to overcome the above-mentioned defects in the prior art and provide a miniature ion source for plasma timing ignition, which has stable and reliable ignition, short ignition start-up time, waterproof function, simple structure, compact structure, low cost and long service life.

[0006] To achieve the above-mentioned purpose, the present invention provides a miniature ion source for plasma timing ignition, characterized in that it includes a base, an anode nested on the base, a cathode installed on one side of the anode, a labyrinth isolation ceramic layer installed between the anode and the cathode, an insulating cover sleeved on the outer wall of the cathode and sealedly connected to the base, the insulating cover is sealedly connected to the cathode, the interior of the cathode is a vacuum chamber, one side of the cathode is provided with a gas injection hole connected to the vacuum chamber, a first plasma extraction hole connected to the vacuum chamber is provided on the labyrinth isolation ceramic layer, a second plasma extraction hole connected to the first plasma extraction hole is provided on the anode, the size of the second plasma extraction hole is slightly smaller than the first plasma extraction hole, a middle hole connected to the second plasma extraction hole is provided on the base, and the discharge electrode material of the cathode is metal hafnium, metal tantalum or metal titanium.

[0007] Preferably, the labyrinth isolation ceramic layer includes an isolation ceramic nested on a base, a hollow auxiliary ceramic installed between the isolation ceramic and the cathode and nested with the isolation ceramic, and the first plasma extraction hole is arranged on the isolation ceramic.

[0008] Preferably, an annular protrusion is provided on the isolation ceramic, and the hollow auxiliary ceramic is provided with an annular groove nested with the annular protrusion, the outer diameter of the annular groove is larger than the outer diameter of the annular protrusion, the inner diameter of the annular groove is smaller than the inner diameter of the annular protrusion, and the depth of the annular groove is greater than the height of the annular protrusion.

[0009] Preferably, a first sealing ring nested in the base is provided on the outer ring position of the isolation ceramic, and the insulating outer cover is sealed and connected to the base via the first sealing ring.

[0010] Preferably, it further comprises a cover plate mounted on the insulating outer cover, wherein the cover plate fixedly connects the insulating outer cover to the base.

[0011] Preferably, a second sealing ring is arranged between the cathode and the insulating outer cover, and the cathode is sealed and connected to the insulating outer cover via the second sealing ring.

[0012] Preferably, the cathode is an integrated metal hafnium, metal tantalum or metal titanium component.

[0013] Preferably, the main body of the cathode is a stainless steel component, the inner wall and the inner end surface of the stainless steel component are both metal sheets, and the metal sheets are made of metal hafnium, metal tantalum or metal titanium.

[0014] The anode is a metal molybdenum component.

[0015] Preferably, the product of the distance between the anode and the cathode and the gas pressure in the vacuum chamber is in the range of 200 Pa·cm to 2000 Pa·cm.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] The present invention is provided with a base, which is convenient for connecting the present invention with subsequent structures, wherein an anode is arranged on the base, a cathode is arranged on one side of the anode, and a labyrinth isolation ceramic layer is installed between the anode and the cathode, the labyrinth isolation ceramic layer is used to isolate the cathode and the anode to prevent a short circuit between the cathode and the anode, and the outer wall of the cathode is provided with an insulating cover sealed with the base, and the insulating cover plays the role of insulating and protecting the cathode. When working, the gas required for ionization is injected into the gas injection hole on the cathode. After the gas enters the vacuum chamber, the gas generates plasma through the discharge of the anode and the cathode, wherein the size of the second plasma extraction hole of the anode is slightly smaller than The first plasma extraction hole of the labyrinth isolation ceramic layer leaves a sufficiently small anode discharge area, so that gas discharge generates high-density plasma near the anode. Through this pressure difference, the plasma in the vacuum chamber is ejected from the first plasma extraction hole of the labyrinth isolation ceramic layer, the second plasma extraction hole of the anode and the middle hole of the base in sequence, thereby realizing the timed ignition operation of the plasma. In addition, the discharge electrode material of the cathode is metal hafnium, metal tantalum or metal titanium, so that it has the advantages of small sputtering yield, rapid ignition, and precise and stable ignition timing. The present invention also has the advantages of simple and compact structure, waterproof function and long service life. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 It is a front view of a micro ion source for plasma timing ignition provided by the present invention;

[0020] Figure 2 yes Figure 1 Sectional view at AA;

[0021] Figure 3 yes Figure 2 The area A in the middle is an enlarged view. DETAILED DESCRIPTION

[0022] In order to make the purpose, technical solution and advantages of the embodiments of the present invention clearer, the technical solution in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are 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 creative work are within the scope of protection of the present invention.

[0023] like Figure 1-Figure 3 As shown, the present invention provides a miniature ion source for plasma timing ignition, comprising a base 1, an anode 2 nested on the base 1, a cathode 3 installed on one side of the anode 2, a labyrinth isolation ceramic layer 4 installed between the anode 2 and the cathode 3, an insulating outer cover 5 sleeved on the outer wall of the cathode 3 and sealed with the base 1, the insulating outer cover 5 is sealed with the cathode 3, the interior of the cathode 3 is a vacuum chamber 31, one side of the cathode 3 is provided with a gas injection hole 32 connected to the vacuum chamber 31, the labyrinth isolation ceramic layer 4 is provided with a first plasma extraction hole 41 connected to the vacuum chamber 31, the anode 2 is provided with a second plasma extraction hole 21 connected to the first plasma extraction hole 41, the size of the second plasma extraction hole 21 is slightly smaller than the first plasma extraction hole 41, and the base 1 is provided with a middle hole 11 connected to the second plasma extraction hole 21.

[0024] Specifically, the base 1 is used to connect the present invention with subsequent structures, the cathode 3 is in a cylindrical shape, the anode 2 is a hollow component, the labyrinth isolation ceramic layer 4 is used to isolate the cathode 3 and the anode 2 to prevent short circuit between the cathode 3 and the anode 2, the insulating cover 5 plays the role of insulating and protecting the cathode 3, the gas injection hole 32 is used to inject hydrogen or helium, the first plasma extraction hole 41 and the second plasma extraction hole 21 are respectively horn holes symmetrically arranged with each other, and the design of the second plasma extraction hole 21 being slightly smaller than the first plasma extraction hole 41 leaves a sufficiently small discharge area of ​​the anode 2, so that the gas discharge generates a high-density plasma near the anode 2, and the plasma located in the vacuum chamber 31 is ejected outward by this pressure difference, the discharge electrode material of the cathode 3 is metal hafnium, metal tantalum or metal titanium, and the material of the anode 2 is metal molybdenum. Since the anode 2 and the cathode 3 are made of this material, the present invention has the advantages of small sputtering yield, rapid ignition, and precise and stable ignition timing.

[0025] During operation, the required ionized gas is injected into the gas injection hole 32 on the cathode 3. After the gas enters the vacuum chamber 31, the gas generates plasma through the discharge of the anode 2 and the cathode 3. The plasma is ejected from the first plasma extraction hole 41 of the labyrinth isolation ceramic layer 4, the second plasma extraction hole 21 of the anode 2 and the middle hole 11 of the base 1 in sequence, thereby realizing the timed ignition operation of the plasma. The present invention has the advantages of small sputtering yield, rapid ignition, precise and stable ignition timing, simple and compact structure, waterproof function and long service life.

[0026] The base 1 is provided with a plurality of mounting holes 12 and an annular sealing ring receiving groove 13, which are inserted into the mounting holes 12 to facilitate connection of the present invention with subsequent structures. The receiving groove 13 is used to place the sealing ring, which plays a role in sealing connection between the present invention and subsequent structures. In addition, for the sake of aesthetics and convenience of processing and assembly of parts, the base 1, anode 2, labyrinth isolation ceramic layer 4, cathode 3 and insulating outer cover 5 are all coaxially arranged.

[0027] The cathode 3 can be an integrated metal hafnium, metal tantalum or metal titanium component, or a stainless steel component with a metal sheet 9 arranged on the inner wall and the inner end face of the stainless steel component, wherein the metal sheet 9 is made of metal hafnium, metal tantalum or metal titanium. This cathode using a stainless steel component as the main body can reduce production costs as much as possible.

[0028] The labyrinth isolation ceramic layer 4 includes an isolation ceramic 42 nested in the middle of the base 1, a hollow auxiliary ceramic 43 installed between the isolation ceramic 42 and the cathode 3 and nested with the isolation ceramic 42, the first plasma extraction hole 41 is set on the isolation ceramic 42, the isolation ceramic 42 is used to isolate the cathode 3 and the anode 2, ensuring that the anode 2 has a very small discharge area, the hollow auxiliary ceramic 43 effectively contains the metal objects sputtered by the cathode 3, can prevent the accumulation of metal objects, prevent the cathode 3 and the anode 2 from being conductive, and prevent a short circuit.

[0029] Specifically, the isolation ceramic 42 is provided with an annular protrusion 421, and the hollow auxiliary ceramic 43 is provided with an annular groove 431 nested with the annular protrusion 421, the outer diameter of the annular groove 431 is larger than the outer diameter of the annular protrusion 421, the inner diameter of the annular groove 431 is smaller than the inner diameter of the annular protrusion 421, and the depth of the annular groove 431 is greater than the height of the annular protrusion 421. The way in which the isolation ceramic 42 and the hollow auxiliary ceramic 43 are nested with each other can completely solve the problem of accumulation short circuit caused by metal objects sputtered from the cathode 3.

[0030] A first sealing ring 6 nested in the base 1 is provided on the outer ring of the isolation ceramic 42 , and the insulating cover 5 is sealed and connected to the base 1 via the first sealing ring 6 , thereby ensuring a good sealing effect between the insulating cover 5 and the base 1 .

[0031] The present invention also includes a cover plate 7 mounted on the insulating cover 5, and the cover plate 7 fixedly connects the insulating cover 5 to the base 1. Through the design of the cover plate 7, the insulating cover 5 and the base 1 are more firmly fixed, and a good sealing effect between the insulating cover 5 and the base 1 is also ensured.

[0032] A second sealing ring 8 is installed between the cathode 3 and the insulating outer cover 5 . The cathode 3 is sealed and connected to the insulating outer cover 5 via the second sealing ring 8 , thereby ensuring a good sealing effect between the insulating outer cover 5 and the cathode 3 .

[0033] The product value of the distance between the anode 2 and the cathode 3 and the gas pressure in the vacuum chamber 31 ranges from 200Pa·cm to 2000Pa·cm. The gas pressure in the vacuum chamber 31 can be calculated by using the gas flow rate, the inner diameter of the gas injection hole, the inner diameter of the first plasma extraction hole 41, the inner diameter of the second plasma extraction hole 21 and the volume of the vacuum chamber 31, thereby ensuring that the product value of the distance between the anode 2 and the cathode 3 and the gas pressure in the vacuum chamber 31 can be between 200Pa·cm and 2000Pa·cm. The product value within this range can make it have the advantages of small sputtering yield, rapid ignition, and precise and stable ignition timing.

[0034] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A miniature ion source for plasma timing ignition, characterized in that: The invention comprises a base (1), an anode (2) nested on the base (1), a cathode (3) installed on one side of the anode (2), a labyrinth isolation ceramic layer (4) installed between the anode (2) and the cathode (3), an insulating outer cover (5) sleeved on the outer wall of the cathode (3) and sealedly connected to the base (1), the insulating outer cover (5) being sealedly connected to the cathode (3), the interior of the cathode (3) being a vacuum chamber (31), one side of the cathode (3) being provided with a gas injection hole (32) connected to the vacuum chamber (31), the labyrinth isolation ceramic layer (4) being provided with a first plasma extraction hole (41) connected to the vacuum chamber (31), and the anode (2) being provided with a second plasma extraction hole (21) connected to the first plasma extraction hole (41) The size of the second plasma extraction hole (21) is slightly smaller than that of the first plasma extraction hole (41), the base (1) is provided with a middle hole (11) connected to the second plasma extraction hole (21), and the discharge electrode material of the cathode (3) is metal hafnium, metal tantalum or metal titanium; The labyrinth isolation ceramic layer (4) comprises an isolation ceramic (42) nested on a base (1), a hollow auxiliary ceramic (43) installed between the isolation ceramic (42) and a cathode (3) and nested with the isolation ceramic (42), and the first plasma extraction hole (41) is arranged on the isolation ceramic (42).

2. A miniature ion source for plasma timing ignition according to claim 1, characterized in that: The isolation ceramic (42) is provided with an annular protrusion (421), and the hollow auxiliary ceramic (43) is provided with an annular notch (431) nested with the annular protrusion (421), the outer diameter of the annular notch (431) is larger than the outer diameter of the annular protrusion (421), the inner diameter of the annular notch (431) is smaller than the inner diameter of the annular protrusion (421), and the depth of the annular notch (431) is greater than the height of the annular protrusion (421).

3. A miniature ion source for plasma timing ignition according to claim 1, characterized in that: A first sealing ring (6) is arranged on the outer ring of the isolation ceramic (42) and is nested in the base (1). The insulating outer cover (5) is sealedly connected to the base (1) via the first sealing ring (6).

4. A miniature ion source for plasma timing ignition according to claim 3, characterized in that: It also includes a cover plate (7) mounted on the insulating outer cover (5), wherein the cover plate (7) fixedly connects the insulating outer cover (5) and the base (1).

5. The micro ion source for plasma timing ignition according to claim 1, characterized in that: A second sealing ring (8) is arranged between the cathode (3) and the insulating outer cover (5), and the cathode (3) is sealedly connected to the insulating outer cover (5) via the second sealing ring (8).

6. A miniature ion source for plasma timing ignition according to claim 1, characterized in that: The cathode (3) is an integrated metal hafnium, metal tantalum or metal titanium component.

7. A miniature ion source for plasma timing ignition according to claim 1, characterized in that: The main body of the cathode (3) is a stainless steel component, the inner wall and the inner end surface of the stainless steel component are both metal sheets (9), and the metal sheets (9) are made of metal hafnium, metal tantalum or metal titanium.

8. The micro ion source for plasma timing ignition according to claim 1, characterized in that: The anode (2) is a metal molybdenum component.

9. The micro ion source for plasma timing ignition according to claim 1, characterized in that: The product value of the distance between the anode (2) and the cathode (3) and the gas pressure in the vacuum chamber (31) ranges from 200 Pa·cm to 2000 Pa·cm.

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