Radio frequency linear plasma generating device with impedance module

Abstract

The utility model belongs to the technical field of plasma radiation device, especially relates to a radio frequency linear plasma generating device with impedance module, including the accommodating space and impedance module that are composed of main part and air inlet plate, the main part includes the first main body and second main body that are matched, is provided with ceramic pipe and the electrode that sets up in ceramic pipe in accommodating space, the first main body and second main body are enclosed after combination with the air inlet channel and the discharge cavity that are formed with the ceramic pipe and the air inlet channel intercommunication between them, impedance module one end is connected with the electrically conductive column, one end is connected radio frequency connector, the other end is connected air inlet plate ground connection. Relative to the prior art, the utility model passes through the matching impedance design module, makes input cable temperature rise < 60 DEG C, improves cable use time length. Matching network power consumption is reduced from 350W to 80W, and the reduction is 55%. Improve the hydrophilicity, and the contact angle is optimized from > 60 DEG to < 10 DEG. The problem that radio frequency linear plasma cleaning machine can only one kind of frequency radio frequency power supply is solved.

Description

Technical Field

[0001] This utility model belongs to the technical field of plasma radiation devices, and specifically relates to a radio frequency linear plasma generator with an impedance module. Background Technology

[0002] The radio frequency (RF) linear plasma cleaner mainly consists of two parts: an RF power supply and an RF plasma discharge head. Its working principle is as follows: the electrodes are isolated by a ceramic tube (insulating medium), with a certain gap to allow the process gas to pass through. A high voltage is applied between the electrodes and the grounded negative plate to generate a high-voltage electric field, ionizing the process gas passing through the electrodes, thus generating plasma. The plasma is discharged through the outlet slit of the grounded negative plate onto the surface of the product to be treated. The ionized process gas contains a large number of electrons, ions, free radicals, and metastable molecules and atoms. These substances will produce physical and chemical reactions on the product surface, such as oxidation, reduction, pyrolysis, cross-linking, and polymerization, altering the surface properties of the sample. This optimizes the surface performance of the material, increasing its hydrophobicity, stainability, adhesion, antistatic properties, and biocompatibility, achieving cleaning, modification, and etching purposes.

[0003] When a radio frequency linear plasma radiation device is powered on, it is called "discharge." Currently, radio frequency linear plasma cleaners on the market suffer from at least one of the following problems: 1. Input cable temperature rise exceeds 70℃ (IEC standard limit 60℃), leading to cable insulation aging; insufficient heat dissipation of the radio frequency matching network causes saturation failure of magnetic components; 2. Narrow application range, limited to a single process gas, only reducing gases such as hydrogen and argon can be used; 3. Poor material compatibility: high-temperature sensitive materials (PI-based flexible circuit boards) have a tolerance threshold <80℃, while existing equipment processes at temperatures ≥120℃; 4. Poor cleaning effect, hydrophilic modified contact angle >60°; 5. Limited radio frequency power supply, only 13.56MHz power can be used; 6. The connection distance between the matching unit and the nozzle is within 500mm.

[0004] To solve the above-mentioned technical problems, this utility model provides a radio frequency plasma generator, which has at least the following advantages:

[0005] First, it breaks through the thermal management bottleneck, solves the insulation aging problem caused by the temperature rise of the RF input cable >70℃ (16.7% exceeding the standard), eliminates the thermal saturation failure of the matching network magnetic components, and ensures that the system can operate continuously at ≤60℃ according to IEC standards.

[0006] Second, the process gas matrix is ​​expanded to overcome the limitation of existing equipment being only applicable to reducing gases such as O2 / Ar, and to achieve precise control of argon-hydrogen mixtures, argon-oxygen mixers, etc., thus extending the compatibility of process gases to the field of semiconductor photoresist cleaning.

[0007] Third, achieve low-temperature precision processing, overcome the process adaptation problem of heat-sensitive materials (heat resistance threshold <80℃), and eliminate the risk of material burns caused by high temperatures ≥120℃.

[0008] Fourth, improve the surface modification efficiency by optimizing the hydrophilic modification contact angle from >60° to <10°.

[0009] Fifth, it solves the problem that the RF linear plasma cleaner can only use one frequency RF power supply, allowing the RF linear plasma cleaner to be equipped with other frequency RF power supplies.

[0010] Sixth, improve the processing efficiency of the radio frequency linear plasma cleaner; the processing effect is the same when the conveyor belt speed is 25mm / s as when it is 10mm / s.

[0011] Seventh, the coaxial length from the mate to the gun head is within a connection range of 1.5 meters to 5 meters, making it more convenient for customization and installation in different on-site environments. Utility Model Content

[0012] The purpose of this invention is to address the aforementioned shortcomings of existing technologies by employing ingenious structural design, such as adding an impedance module to reduce the input cable temperature rise to <60℃, thereby extending cable lifespan; reducing the matching network power consumption from 350W to 80W, a reduction of 55%; improving hydrophilicity by optimizing the contact angle from >60° to <10°; solving the problem that RF linear plasma cleaners can only use one frequency RF power supply, allowing switching between 13.56MHz and 27.12MHz frequency power supplies; increasing the types of process gases, thus expanding the application range; and improving the product processing efficiency of the RF linear plasma cleaner.

[0013] To overcome the aforementioned deficiencies in the prior art, the technical solution provided by this utility model is as follows:

[0014] A radio frequency linear plasma generator with an impedance module includes a housing space composed of a main body and an inlet plate, and an impedance module. The main body includes a matching first main body and a second main body. A ceramic tube and an electrode disposed within the ceramic tube are disposed in the housing space. The inlet plate is provided with a gas pipe connector and a through hole for a conductive column to pass through. The conductive column is electrically connected to the electrode and is also connected to a radio frequency connector. The first main body and the second main body are combined to form a gas equalization groove. The first main body and the second main body, together with the ceramic tube, form an inlet gas channel and a discharge chamber communicating with the inlet gas channel. Process gas enters from the gas pipe connector, passes through the gas equalization groove and the inlet gas channel, and then reaches the discharge chamber.

[0015] One end of the impedance module is connected to the conductive post, the other end is connected to the radio frequency connector, and the other end is connected to the air intake plate ground.

[0016] As an improvement to the radio frequency linear plasma generator with an impedance module, the impedance module is an impedance circuit formed by at least one inductor and capacitor connected in series or in parallel.

[0017] As an improvement to the radio frequency linear plasma generator with an impedance module, the impedance module is a series circuit formed by an inductor and a capacitor, wherein the first end of the inductor is connected to one end of the capacitor, the second end of the inductor is connected to the radio frequency connector, the third end of the inductor is connected to the conductive post, and the other end of the capacitor is grounded.

[0018] As an improvement to the radio frequency linear plasma generator with impedance module, the bottom region of the discharge cavity is chamfered, and an exhaust slit communicating with the discharge cavity is formed between the lower ends of the first body and the second body.

[0019] As an improvement to the radio frequency linear plasma generator with an impedance module, the chamfer has an inclination angle of 60°-70°.

[0020] As an improvement to the radio frequency linear plasma generator with an impedance module, the distance between the bottom end of the electrode and the gas outlet slit is 5mm-6mm.

[0021] As an improvement to the radio frequency linear plasma generator with impedance module, the conductive column includes an insulating column, a high-voltage connecting rod, and a high-voltage connecting piece; one end of the high-voltage connecting piece is connected to the high-voltage connecting rod, and the other end passes through the ceramic tube and is connected to the electrode; the high-voltage connecting rod is disposed inside the insulating column and is connected to the radio frequency connector.

[0022] The radio frequency connector, the high-voltage connecting rod, the high-voltage connecting piece, and the electrode are fixed together and connected to form a high-voltage positive electrode; the air intake plate, the first main body, and the second main body are fixed together and connected to form a negative electrode ground.

[0023] As an improvement to the radio frequency linear plasma generator with an impedance module, the ceramic tube is a tube body formed by isostatic pressing.

[0024] As an improvement to the radio frequency linear plasma generator with impedance module, the width of the exhaust slit is 0.3-1mm.

[0025] As an improvement to the radio frequency linear plasma generator with an impedance module, the process gas is a mixture of argon and hydrogen. Specifically, the mixture comprises 95%–99% argon and 5%–1% hydrogen.

[0026] As an improvement to the radio frequency linear plasma generator with an impedance module, the impedance module is housed inside a shield, and the impedance module and the shield form an integral unit.

[0027] In operation, the gas source enters through the gas pipe connector, passes sequentially through the gas equalization tank and the inlet gas channel, and then reaches the discharge chamber. The RF connector, high-voltage connecting rod, high-voltage connecting piece, and electrode are fixed together and connected to form the high-voltage positive electrode. The electrode is inserted into the ceramic tube, which serves as the discharge medium. The inlet plate, the first main body, and the second main body are fixed together and connected to form the negative electrode ground. After connecting to the RF power supply, it will discharge normally. When a high voltage is applied between the high-voltage positive and negative electrodes, a high-voltage electric field is generated between the high-voltage electrode and the negative electrode. This ionizes the process gas passing between the two electrodes to generate plasma, which is then discharged through the outlet slit onto the surface of the product to be treated.

[0028] Compared with the prior art, the present invention has at least the following advantages:

[0029] First, this invention optimizes the structure of the discharge chamber: Process gas flows into the discharge chamber through a gas equalization tank, forming a tip discharge at both ends. At this point, the plasma on both sides is still unstable. If it is directly blown onto the product to be processed, static electricity will be generated due to the potential difference between positive and negative charges. If the positive charge exceeds the negative charge, it is positive static electricity; otherwise, it is negative static electricity. This invention cleverly sets a chamfer at the bottom of the discharge chamber. This area attracts the plasma from both ends of the discharge chamber, neutralizing the positive and negative charges within this area, ensuring the internal plasma is electrically neutral, and controlling the plasma concentration to guarantee discharge uniformity. This achieves static electricity control within 0~±30V, lower than the national static electricity standard of ±100V and ±35V for the microelectronics industry.

[0030] Secondly, the combination of the gas distribution groove and the outlet slit can achieve the functions of limiting flow rate, enhancing physical impact, and continuous heat dissipation. That is, through its unique gas distribution structure, this invention can remove some of the heat generated during discharge.

[0031] Third, the ceramic tube of this utility model adopts an isostatic pressing process, which has high precision, no bubbles on the ceramic surface, and uniform discharge.

[0032] Fourth, this invention, through its impedance matching design module, reduces the input cable temperature rise to <60℃, thus extending cable lifespan. The matching network power consumption is reduced from 350W to 80W, a 55% reduction. Hydrophilicity is improved, with the contact angle optimized from >60° to <10°. It solves the problem of RF linear plasma cleaners only supporting one frequency power supply, allowing switching between 13.56MHz and 27.12MHz power supplies. The range of process gases is increased, expanding the application scope. Finally, it improves the product processing efficiency of the RF linear plasma cleaner. Attached Figure Description

[0033] The present invention and its beneficial technical effects will be further described in detail below with reference to the accompanying drawings and specific embodiments, wherein:

[0034] Figure 1 This is one of the three-dimensional structural schematic diagrams of this utility model;

[0035] Figure 2 This is the second three-dimensional structural schematic diagram of this utility model;

[0036] Figure 3 This is an exploded structural diagram of the present invention;

[0037] Figure 4 This is an exploded structural diagram of a portion of the present invention;

[0038] Figure 5 This is the circuit diagram of the impedance module in this utility model;

[0039] Figure 6 This is a cross-sectional view of the discharge cavity in this invention. Detailed Implementation

[0040] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present utility model.

[0041] It should be noted that all directional indicators (such as up, down, left, right, front, back, etc.) in this utility model embodiment are only used to explain the relative positional relationship and movement of each component in a specific posture (as shown in the figure). If the specific posture changes, the directional indicator will also change accordingly.

[0042] Furthermore, the use of terms such as "first" and "second" in this utility model is for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of the various embodiments can be combined with each other, but only on the basis of being achievable by those skilled in the art. If the combination of technical solutions is contradictory or impossible to implement, such a combination of technical solutions should be considered non-existent and not within the scope of protection claimed by this utility model.

[0043] like Figures 1-6As shown, the present invention provides a radio frequency linear plasma generator with an impedance module, comprising a accommodating space and an impedance module 10 composed of a main body 1 and an air inlet plate 2. The main body 1 includes a matching first main body 11 and a second main body 12. A ceramic tube 3 and an electrode 4 disposed within the ceramic tube 3 are disposed in the accommodating space. The air inlet plate 2 is provided with a gas pipe connector 5 and a through hole through which a conductive post 6 can pass. The conductive post 6 is electrically connected to the electrode 4 and is also connected to a radio frequency connector 7. The first main body 11 and the second main body 12 are combined to form a gas equalization groove 13. The first main body 11 and the second main body 12, together with the ceramic tube 3, form an air inlet channel 14 and a discharge cavity 15 communicating with the air inlet channel 14. The process gas enters from the gas pipe connector 5, passes through the gas equalization groove 13 and the air inlet channel 14, and reaches the discharge cavity 15. A chamfer 16 is provided in the bottom area of ​​the discharge cavity 15. An outlet slit 17 communicating with the discharge cavity 15 is formed between the lower ends of the first main body 11 and the second main body 12. The width of the vent slit 17 is 0.3-1mm.

[0044] Impedance module 10 is connected to conductive post 6 at one end, to RF connector 7 at the other end, and to ground via air intake plate 2 at the other end. Impedance module 10 can improve effective output power, enhance cleaning effect, and reduce static electricity.

[0045] Impedance module 10 is an impedance circuit formed by at least one inductor and capacitor connected in series or in parallel.

[0046] Impedance module 20 is housed inside shielding cover 30, and impedance module 20 and shielding cover 30 form a whole.

[0047] This invention, through a matching impedance design module, reduces the input cable temperature rise to <60℃, thus extending cable lifespan. The matching network power consumption is reduced from 350W to 80W, a 55% reduction. Hydrophilicity is improved, with the contact angle optimized from >60° to <10°. It solves the problem of RF linear plasma cleaners only being able to use one type of RF power supply, allowing switching between a 13.56MHz and a 27.12MHz frequency power supply. The range of process gases is increased, expanding the application scope. The processing efficiency of the RF linear plasma cleaner is improved. Specifically:

[0048] 1. Cable temperature rise <60℃, power consumption reduced from 350W to 80W: In the event of impedance mismatch, some RF energy is reflected back to the power supply and cable, converting into Joule heat. The impedance matching design module adjusts the capacitive and inductive reactance values ​​(Z=jωL+). ), making the source-end output impedance Z s With plasma load impedance Z L Conjugate matching (Zs=Z) L ∗ This reduces the reflection coefficient to near zero, minimizing heat loss in cables and matching networks.

[0049] Switching between 2.13.56MHz and 27.12MHz power supplies: By changing the inductor and capacitor values, the resonant frequency of the impedance module can be adjusted to meet the specified frequency. The circuit achieves resonance at 13.56MHz and 27.12MHz respectively, ensuring efficient energy transfer at both frequencies. The Q value of the LC circuit can be rationally designed to broaden the bandwidth of the matching network, covering both 13.56MHz and 27.12MHz frequency bands.

[0050] 3. Improved hydrophilicity: After impedance matching, the effective power P eff Maximize (P) eff =P 输入 -P 反射 The electron density within the discharge cavity increases significantly. Higher concentrations of active particles (such as ·OH radicals) enhance surface hydrophilic modification and reduce the contact angle.

[0051] 4. Improved uniformity: Combined with the chamfered design of the discharge cavity, the plasma distribution in the charge neutralization region is stabilized, avoiding uneven modification caused by local over-discharge.

[0052] 5. Expand process gas compatibility

[0053] Different gases (such as Ar / O and pure O2 mixtures) have different ionization potentials (Ar: 15.8 eV, O2: 12.1 eV) and collision cross sections, resulting in variations in load impedance. The impedance module maintains a stable electric field strength E through dynamic matching, ensuring that different gases are ionized in the high-efficiency range.

[0054] 6. Improved processing efficiency

[0055] After matching, the effective power is increased by about 77% (estimated from the reflection loss of 55%), and the plasma output per unit time is increased, allowing for faster conveyor belt speed without affecting the processing depth.

[0056] In summary, this utility model also has at least the following advantages:

[0057] First, it breaks through the thermal management bottleneck, solves the insulation aging problem caused by the temperature rise of the RF input cable >70℃ (16.7% exceeding the standard), eliminates the thermal saturation failure of the matching network magnetic components, and ensures that the system can operate continuously at ≤60℃ according to IEC standards.

[0058] Second, the process gas matrix is ​​expanded to overcome the limitation of existing equipment that only supports reducing gases such as O, enabling precise control of argon-hydrogen mixtures, argon-oxygen mixers, etc., thus extending the compatibility of process gases to the field of semiconductor photoresist cleaning.

[0059] Third, achieve low-temperature precision processing, overcome the process adaptation problem of heat-sensitive materials (heat resistance threshold <80℃), and eliminate the risk of material burns caused by high temperatures ≥120℃.

[0060] Fourth, improve the surface modification efficiency by optimizing the hydrophilic modification contact angle from >60° to <10°.

[0061] Fifth, it solves the problem that the RF linear plasma cleaner can only use one frequency RF power supply, allowing the RF linear plasma cleaner to be equipped with other frequency RF power supplies.

[0062] Sixth, improve the processing efficiency of the radio frequency linear plasma cleaner; the processing effect is the same when the conveyor belt speed is 25mm / s as when it is 10mm / s.

[0063] In this embodiment, the impedance module 10 is a series circuit formed by an inductor 101 and a capacitor 102, wherein the first end of the inductor 101 is connected to one end of the capacitor 102, the second end of the inductor 101 is connected to the radio frequency connector 7, the third end of the inductor 101 is connected to the conductive post 6, and the other end of the capacitor 102 is grounded.

[0064] This invention optimizes the structure of the discharge cavity through finite element simulation and the simulation results: the process gas flows from the gas equalization tank 13 to the discharge cavity 15, and at the left and right ends of the discharge cavity 15 ( Figure 4 A tip discharge is formed at the A and B ends of the discharge cavity. At this time, the plasma on both sides is still unstable. If it is blown directly onto the product to be treated, static electricity will be generated due to the potential difference between the positive and negative charges. If the positive charge is greater than the negative charge, it is positive static electricity, and vice versa. This invention cleverly uses the bottom region of the discharge cavity 15 ( Figure 4 The C region is chamfered by 16. This region attracts plasma from both ends of the discharge cavity. The positive and negative charges are neutralized in this region to ensure that the internal plasma is electrically neutral and to control the plasma concentration to ensure the uniformity of discharge. This achieves the goal of electrostatic control at 0~±30V, which is lower than the national electrostatic standard value of ±100V and ±35V in the microelectronics industry.

[0065] The combination of the gas distribution groove 13 and the gas outlet slit 17 can achieve the functions of limiting flow rate, enhancing physical impact, and continuous heat dissipation. That is, through its unique gas distribution structure, this invention can remove some of the heat generated during discharge.

[0066] The chamfer angle of chamfer 16 is 60°-70°.

[0067] The distance between the bottom of electrode 4 and the outlet slit 17 is 5mm-6mm.

[0068] In short, this invention utilizes finite element simulation and combines the simulation results to optimize the internal structure and discharge gap of the discharge cavity 15, maintaining the plasma concentration in the ionization region to reduce static electricity. Specifically, this invention optimizes the structure between the discharge region and the outlet slit 17, controlling an appropriate discharge gap (the distance from electrode 4 to outlet slit 17) to maintain the internal plasma concentration and discharge uniformity, thereby reducing static electricity.

[0069] The conductive post 6 includes an insulating post 61, a high-voltage connecting rod 62, and a high-voltage connecting piece 63. One end of the high-voltage connecting piece 63 is connected to the high-voltage connecting rod 62, and the other end passes through the ceramic tube 3 and is connected to the electrode 4. The high-voltage connecting rod 62 is disposed inside the insulating post 61 and is connected to the radio frequency connector 7. The radio frequency connector 7, the high-voltage connecting rod 62, the high-voltage connecting piece 63, and the electrode 4 are fixed together and connected to form a high-voltage positive electrode. The air intake plate 2, the first main body 11, and the second main body 12 are fixed together and connected to form a negative electrode ground.

[0070] The ceramic tube 3 is formed by isostatic pressing, which results in high precision, no bubbles on the ceramic surface, and uniform discharge.

[0071] The process gas is a mixture of argon and hydrogen, specifically, the mixture consists of 95% to 99% argon and 5% to 1% hydrogen.

[0072] In use, the gas source enters through the gas pipe connector 5, passes through the gas equalization groove 13 and the air intake channel 14 in sequence, and then reaches the discharge chamber 15. The RF connector 7, high-voltage connecting rod 62, high-voltage connecting piece 63, and electrode 4 are fixed together and connected to form a high-voltage positive electrode. Electrode 4 is inserted into the ceramic tube 3, which serves as the discharge medium. The air intake plate 2, the first main body 11, and the second main body 12 are fixed together and connected to form a negative electrode ground. After being connected to the RF power supply, it will discharge normally. When a high voltage is applied between the high-voltage positive and negative electrodes, a high-voltage electric field is generated between the high-voltage electrode and the negative electrode. The process gas passing between the two electrodes is ionized to generate plasma. The plasma is discharged to the surface of the product to be treated through the exhaust slit 17 to achieve surface treatment of the product.

[0073] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and structure of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A radio frequency linear plasma generator with an impedance module, characterized in that: The device includes a accommodating space and an impedance module consisting of a main body and an air inlet plate. The main body includes a matching first main body and a second main body. A ceramic tube and an electrode disposed within the ceramic tube are disposed in the accommodating space. The air inlet plate is provided with a gas pipe connector and a through hole for a conductive column to pass through. The conductive column is electrically connected to the electrode and is also connected to an RF connector. The first main body and the second main body are combined to form a gas equalization groove. The first main body and the second main body, together with the ceramic tube, form an air inlet channel and a discharge cavity communicating with the air inlet channel. The process gas enters from the gas pipe connector, passes through the gas equalization groove and the air inlet channel, and then reaches the discharge cavity. One end of the impedance module is connected to the conductive post, the other end is connected to the radio frequency connector, and the other end is connected to the air intake plate ground.

2. The radio frequency linear plasma generator with impedance module according to claim 1, characterized in that: The impedance module is an impedance circuit formed by connecting at least one inductor and a capacitor in series or in parallel.

3. The radio frequency linear plasma generator with impedance module according to claim 2, characterized in that: The impedance module is a series circuit formed by an inductor and a capacitor, wherein the first end of the inductor is connected to one end of the capacitor, the second end of the inductor is connected to the RF connector, the third end of the inductor is connected to the conductive post, and the other end of the capacitor is grounded.

4. The radio frequency linear plasma generator with impedance module according to claim 1, characterized in that: The bottom region of the discharge cavity is chamfered, and an outlet slit communicating with the discharge cavity is formed between the lower ends of the first body and the second body.

5. The radio frequency linear plasma generator with impedance module according to claim 4, characterized in that: The chamfer angle is 60°-70°.

6. The radio frequency linear plasma generator with impedance module according to claim 4, characterized in that: The distance between the bottom of the electrode and the vent slit is 5mm-6mm.

7. The radio frequency linear plasma generator with impedance module according to claim 1, characterized in that: The conductive post includes an insulating post, a high-voltage connecting rod, and a high-voltage connecting piece; one end of the high-voltage connecting piece is connected to the high-voltage connecting rod, and the other end passes through the ceramic tube and is connected to the electrode; the high-voltage connecting rod is disposed inside the insulating post and is connected to the radio frequency connector. The radio frequency connector, the high-voltage connecting rod, the high-voltage connecting piece, and the electrode are fixed together and connected to form a high-voltage positive electrode; the air intake plate, the first main body, and the second main body are fixed together and connected to form a negative electrode ground.

8. The radio frequency linear plasma generator with impedance module according to claim 1, characterized in that: The impedance module is housed inside the shielding cover, and the impedance module and the shielding cover form a whole.

9. The radio frequency linear plasma generator with impedance module according to claim 1, characterized in that: The width of the vent slit is 0.3-1mm.

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