Gas concentration detection device for detecting binary gas concentration

Abstract

The invention relates to a gas concentration detection device for detecting binary gas concentration. The gas concentration detection device comprises a detection module, a sealing sleeve module and a controller module, the detection module comprises a detection cavity, a forming cavity integrally formed with the detection cavity, and a transducer sealed in the forming cavity by using a sealant. The sealing sleeve module has a sleeve container shape matching the shape of the detection module to accommodate and seal the detection chamber of the detection module, and includes an air inlet and an air outlet in fluid communication with the detection chamber. The controller module comprises an electric appliance module with a communication board, a power board and a main control board, a display module with a display screen and a driving board. The detection module, the sealing sleeve module and the controller module are modular assemblies, and the detection module and the sealing sleeve module as well as the detection module and the controller module are matched with each other and are detachably connected with each other. The gas concentration detection device for detecting the binary gas concentration is suitable for gas concentration detection of a gas supply system of a semiconductor thin film process.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of ultrasonic gas concentration detection, and particularly relates to a gas concentration detection device for detecting binary gas concentration. BACKGROUND

[0002] In advanced semiconductor manufacturing, thin film processes are the core link of building nanoscale micro devices. The success or failure and repeatability of these processes are extremely dependent on the accuracy and stability of the process environment in the reaction chamber, and the concentration control of active gas and carrier gas is a crucial parameter.

[0003] Currently, in the process of gas delivery and control in this field, there are the following technical problems to be solved. First, detection accuracy and stability: in advanced atomic layer deposition (ALD) process, only one atomic layer is deposited per cycle, and the control of gas flow requires accurate response and extremely low fluctuation at the level of seconds or even milliseconds. The existing ultrasonic gas concentration detection device is easily affected by the change of gas type, temperature and pressure, and cannot reach the actual detection accuracy required by the process, thus causing the deviation of the actual gas mass flow or molecular density entering the chamber from the set value. This deviation will directly affect the thickness uniformity, chemical composition, step coverage and electrical properties of the thin film, and ultimately lead to inconsistent device performance and yield reduction; the semiconductor production line requires continuous stable operation for 7x24 hours. The long-term drift and zero-point drift of the detection device will gradually change the process conditions, which poses a serious threat to the consistency of mass production. Second, material compatibility and cleanliness: special gases have strong corrosive properties. If the material of the parts (for example, the inner wall of the chamber) in contact with the gas in the detection device is not appropriate, corrosion will occur and particle contaminants will be generated, and the device itself will also fail quickly, polluting the entire gas path system; for nanoscale processes, any submicron particle or metal ion pollution is fatal. The design of the detection device needs to avoid structures such as dead zones and micro-cracks that can easily trap gas or generate particles. Finally, maintenance and repair: the cost of stopping the semiconductor equipment is extremely high. Once the traditional ultrasonic concentration detection device is integrated into the gas path, calibration, maintenance or replacement often requires complex disassembly, long blowing and system restart, which seriously affects the overall efficiency of the equipment; high-precision detection devices need to be calibrated regularly using standard gas. The existing device is usually difficult to calibrate online without disassembling it from the production line, or the online calibration process is complicated, increasing the risk of human error; the non-modular design makes it difficult to troubleshoot and replace parts, often requiring replacement of the entire module, increasing maintenance costs and spare parts inventory pressure.

[0004] Therefore, due to the actual needs of the semiconductor market, there is an urgent need to solve the technical challenges of gas concentration detection devices used for semiconductor deposition gas supply, such as detection accuracy, applicable operating conditions, and ease of maintenance. Summary of the Invention

[0005] The technical problem to be solved by this application is to provide a gas concentration detection device for detecting binary gas concentration that has improved detection accuracy, a wide range of applicable working conditions, and is easy to inspect and maintain.

[0006] To address the aforementioned technical problems, according to embodiments of this application, a gas concentration detection device for detecting the concentration of a binary gas is provided, comprising a detection module, a sealing sleeve module, and a controller module. The detection module includes: a detection chamber having a cylindrical detection space, comprising a circular transmitting wall, a reflecting wall arranged face-to-face and parallel to the transmitting wall, and a side wall disposed between the transmitting wall and the reflecting wall and connecting the two, the side wall having an opening for the gas to be detected to enter and exit; a molded cavity extending upward from the edge of the transmitting wall, disposed back-to-back with the detection chamber and integrally formed with the detection chamber; and a transducer comprising piezoelectric ceramic material, disposed in the molded cavity and adjacent to the transmitting wall, for emitting ultrasonic waves and receiving ultrasonic waves emitted therefrom, transmitted through the transmitting wall and the gas to be detected, and reflected back by the reflecting wall, the transducer being encapsulated in the molded cavity with impedance-matched sealant. The sealing sleeve module has a sleeve container shape matching the shape of the detection module, for accommodating and sealing the detection chamber, including an inlet and an outlet communicating with the detection chamber fluidly. The controller module includes an electrical module, a display module, and a drive board. The electrical module includes a communication board, a power supply board, and a main control board. It receives transmitted and reflected ultrasonic signals from the transducer and converts them into electrical signals representing the concentration of the detected gas using a predetermined algorithm. The display module has a screen that receives the electrical signal representing the concentration of the detected gas from the electrical module and displays it as a digital image. The driver board is located below the electrical module and drives the transducer to emit ultrasonic waves according to the instructions from the electrical module. The detection module, sealing sleeve module, and controller module are modular components, and the detection module and sealing sleeve module, as well as the detection module and controller module, are mated to each other and detachably connected.

[0007] According to embodiments of this application, the predetermined algorithm program may include the following formula: T = 4Z1 * Z2 / (Z1 + Z2)^2 Where T is the sound intensity transmittance, Z1 is the gas acoustic impedance, and Z2 is the solid medium acoustic impedance. C=d / t and X∝1 / C Where C is the speed of sound in the gas, d is the effective length of the acoustic cavity, t is the flight time, and X is the gas concentration; and N = D^2 * f / (4 * C) Where N is the near-field acoustic wave length, D is the diameter of the transducer piezoelectric ceramic, f is the driving frequency, and C is the gas velocity.

[0008] According to an embodiment of this application, the detection chamber may be integrally formed from polyimide (PI) material.

[0009] According to embodiments of this application, the piezoelectric ceramic material of the transducer is PZT-5A or PZT-5H.

[0010] According to an embodiment of this application, the surface roughness of the transmission wall and the reflection wall of the detection chamber can be less than or equal to 0.4.

[0011] According to embodiments of this application, the reflective wall of the detection chamber may have a coating. Preferably, the coating may include a gold coating or a T6 aluminum alloy-diamond carbon film composite coating.

[0012] According to an embodiment of this application, the distance between the transmission wall and the reflection wall of the detection chamber can be between 20-30 mm.

[0013] According to embodiments of this application, the acoustic impedance of the sealant can be in the range of 0.11-3MRayi.

[0014] According to an embodiment of this application, the transducer may be disc-shaped, and its diameter may be between 25-30 mm.

[0015] According to an embodiment of this application, the design environment of the transducer can be hydrogen at a temperature of 150°C with a driving frequency of 500K-5MHz.

[0016] According to embodiments of this application, the air inlet and outlet of the sealing sleeve module may include a vacuum coupling retainer and / or a ferrule fitting pipe joint.

[0017] According to embodiments of this application, the material of the sealing sleeve of the sealing sleeve module may include 316L.

[0018] According to an embodiment of this application, the acoustic impedance coefficient of the PI material can be 3MRayi.

[0019] According to embodiments of this application, the gas concentration detection device for detecting binary gas concentration is suitable for detecting binary gases including carrier gases H2, N2, He or Ar, and active gases SiH4, DCS, NH3, PH3, B2H6, AsH3, GeH4, WF6, Ga(CH3)3 or Si(OC2H5)4.

[0020] According to embodiments of this application, a gas concentration detection device for detecting binary gas concentration is suitable for detecting the gas concentration in a gas supply system for semiconductor thin film processes.

[0021] According to embodiments of this application, semiconductor thin film processes may include MOCVD, PECVD, HDPCVD, and ALD processes.

[0022] Compared with the prior art, the beneficial effects of this application are at least as follows: 1. The detection chamber is made of PI material. PI material is corrosion-resistant and has low particulate contamination, fully meeting the requirements of semiconductor processes. Furthermore, its processing is simple, saving on material processing costs. Moreover, PI material has an acoustic impedance coefficient of 3 MRayi, which has a high degree of matching with the acoustic impedance of gases, making it more conducive to sound wave propagation. Compared with existing metal detection chambers with an acoustic impedance coefficient of approximately 45 MRayi, the acoustic signal intensity of the PI material detection chamber can be increased by 15 times, which is more conducive to sound wavelength distance transmission, enabling more accurate and precise time-of-flight detection of electrical components.

[0023] 2. The detection chamber and the molding chamber are integrally molded, and the transducer is sealed within the molding chamber with sealant, reducing the number of instrument parts, thus saving material costs and reducing manual assembly time. Furthermore, the transducer and detection chamber are integrated into a single detection module, and the display module, electrical modules (communication board, power board, and main control board), and drive board are integrated into a single controller module. The sealing sleeve module is a separate module. Therefore, the detection module, sealing sleeve module, and controller module are all modular components, and the detection module and sealing sleeve module, as well as the detection module and controller module, are mutually compatible and detachably connected. This allows for convenient handling when any module needs repair or replacement, improving maintenance and repair efficiency.

[0024] 3. Utilizing a single-transducer reflective design, the sound wave propagation path within a limited space is doubled due to the transmission path of the sound wave through both emission and reflection during detection, directly doubling the minimum concentration detection limit. Simultaneously, since the transmitting and receiving components use the same transducer with no resonant point difference, this effectively avoids functional problems such as low coupling efficiency and severe inconsistency in emission caused by differences in resonant frequencies among multiple transducers, eliminating the need for transducer selection during system assembly.

[0025] 4. The transducer and modulation frequency are designed according to a high temperature of 150℃ and hydrogen as the carrier gas. The near-field sound wave length is compatible with the working distance of the reflective type, the sound wave coupling efficiency is high, the detectability of the sound wave signal intensity is improved, and the compatibility with the working environment and the types of detectable gases is high.

[0026] 5. Airflow velocity can affect ultrasonic signals, leading to inaccurate detection. In this invention, the airflow direction of the sealing sleeve is distributed at 90° with the air inlet of the detection chamber of the integrated single-lens reflex detection module, and the air outlet of the sealing sleeve is below the air inlet of the detection chamber. The airflow flows from the air inlet to the air outlet through the gap between the outer wall of the detection chamber and the inner wall of the sealing sleeve, having minimal impact on the gas in the detection chamber to be detected. This avoids the influence of the airflow velocity in the sealing chamber on the sound velocity, and thus avoids the influence of the airflow on the detection concentration.

[0027] 6. The unibody design of the single-lens reflex camera reduces production costs by 10 times (material processing costs, component costs, assembly costs, and maintenance costs). The single-lens reflex design lowers the detection limit for the lowest concentration (B₂H₆+H₂) from 1 ppm to 0.5 ppm, improving the instrument's ability to detect the lowest concentration. Instrument noise for concentration (B₂H₆+H₂) is reduced from 1 ppm to 0.25 ppm, improving the instrument's detection precision and accuracy. Attached Figure Description

[0028] Figure 1 This is a perspective view of a gas concentration detection device for detecting the concentration of a binary gas according to an embodiment of this application.

[0029] Figure 2 This is a front view of a gas concentration detection device for detecting binary gas concentration according to an embodiment of this application.

[0030] Figure 3 yes Figure 2 The left view of a gas concentration detection device for detecting the concentration of a binary gas is shown.

[0031] Figure 4 yes Figure 2 The right view of the gas concentration detection device used to detect the concentration of a binary gas is shown.

[0032] Figure 5 yes Figure 2 The image shows a top view of a gas concentration detection device used to detect the concentration of a binary gas.

[0033] Figure 6 It is along Figure 2 The right longitudinal section view of the gas concentration detection device used to detect the concentration of binary gases, taken along the longitudinal centerline.

[0034] Explanation of reference numerals in the attached figures: 10--Controller module, 11--Display module, 12--Electrical module (communication board, power board and main control board). 20--Detection module, 21--Transmitting wall, 21a--Side wall of molding cavity, 21b--Boss of molding cavity, 22--Reflective wall, 23--Side wall, 24--Opening; 30--Sealing sleeve module, 31--Sleeve side wall, 32--Sleeve bottom plate, 33--Air inlet, 34--Air outlet; 40 -- Driver board; 50 -- Transducer. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions in the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. All other embodiments obtained by those skilled in the art based on the embodiments of this application without inventive effort are within the scope of protection of this application. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art to which this application pertains. The terms "comprising" and similar expressions used herein mean that the element or object preceding the word covers the element or object listed after the word and its equivalents, but does not exclude other elements or objects. Unless otherwise specified, the term "connection" as used herein can refer to a direct connection or an indirect connection, i.e., a connection through an intermediate object.

[0036] Controlling the deposition rate in semiconductor deposition processes is a time-consuming and challenging task, requiring extremely precise control of input variables. A key challenge in the front-end delivery system of deposition equipment lies in ensuring accurate control of all gas variables (temperature, pressure, concentration, flow rate, etc.) to guarantee a constant mass of reaction source delivered to the deposition equipment every minute. While precise control of all front-end gas variables is costly, using ultrasonic concentration meters to precisely control the reaction source concentration offers an efficient and economical solution.

[0037] Existing ultrasonic gas concentration meters generally calculate binary gas concentrations based on Time-of-Flight (TOF). The detection chamber and ultrasonic probe are independently packaged devices, typically made of ordinary plastic or metal. In dual-probe designs, the two probes are placed parallel to each other, one emitting and the other receiving ultrasonic signals. For semiconductor gas concentration detection, the acoustic transmission path is generally around 20-30 mm. The transducer drive frequency is typically between 200 kHz and 5 MHz. Transducers and modulation frequencies are generally designed for ambient temperature and pressure air. Semiconductor gas concentration meters require a leakage rate ≤1*10^-10 Pa*m^3 / s, a corrosion-resistant and contamination-free chamber, and concentrations are easily affected by gas temperature, flow rate, and pressure.

[0038] In semiconductor manufacturing, all gases used are high-purity, thus imposing strict requirements on the instruments and equipment that come into contact with these gases. For example, the materials used in these instruments must be corrosion-resistant and highly clean. Therefore, the transducers and chambers of current semiconductor ultrasonic concentration meters are generally made of 316L stainless steel. The acoustic impedance of metal (around 45 M Rayyi) differs significantly from that of gas (around 430 Rayi). The severe signal reflection from the surface of the metal probe is detrimental to sound wave transmission in the gas, resulting in a shorter transmission distance. This shorter propagation path reduces the time-of-flight accuracy, thereby lowering the concentration measurement accuracy. At the same distance, the received acoustic signal is weaker, leading to lower accuracy in the time-of-flight detection by the electrical system, and consequently, lower accuracy in concentration measurement.

[0039] As sound waves propagate through the gas, they also propagate inside the solid cavity. The dual transducer structure causes one transducer to emit a sound wave signal, while the other transducer receives the acoustic signal from the gas and the acoustic signal from the cavity almost simultaneously. The acoustic signal transmitted through the cavity will seriously interfere with the effective acoustic signal in the gas transmission process, resulting in a decrease in the accuracy of the time of flight detected by the electrical device, which in turn leads to a decrease in the accuracy of concentration measurement.

[0040] To reduce the impact of airflow on sound velocity, semiconductor gas ultrasonic concentration meters employ structural design that directs airflow in the direction of sound wave transmission or uses bidirectional sound wave emission algorithms to eliminate the influence of airflow on flight time. However, these methods complicate the structural design, increase costs, and cannot completely eliminate the impact of airflow on concentration accuracy.

[0041] Due to differences in materials, packaging, etc., different transducers will have different resonant frequencies. This difference reduces the coupling efficiency of the transducer, causes severe heat generation when the transducer is working for a long time, resulting in frequency shift and large fluctuations in concentration output. The system assembly requires the individual selection and matching of transducers.

[0042] Because the transducer and modulation frequency are designed for ambient air, the ultrasonic concentration meter suffers from poor compatibility with varying operating temperatures, pressures, and gas types. The fragile transducer requires replacement of the entire instrument upon failure, resulting in long maintenance cycles and high operating costs.

[0043] Based on the experience and knowledge accumulated in the above-mentioned work in this technical field, the applicant provides an integrated single-reflective binary gas ultrasonic concentration meter device.

[0044] The embodiments of this application are described below with reference to the accompanying drawings.

[0045] like Figure 1 As shown, according to an embodiment of this application, a gas concentration detection device for detecting the concentration of binary gases is provided, which includes a controller module 10, a detection module 20, and a sealing sleeve module 30.

[0046] like Figure 6 As shown and combined Figures 2 to 4 The detection module 20 includes a detection chamber, a forming chamber, and a transducer 50.

[0047] The detection chamber has a cylindrical detection space, including a circular transmission wall 21, a reflective wall 22 facing and parallel to the transmission wall 21, and a side wall 23 located between and connecting the transmission wall 21 and the reflective wall 22. The side wall 23 has an opening 24 for the gas to be detected to enter and exit. The detection chamber can be integrally formed from polyimide (PI). PI material is corrosion-resistant, has low pollution, fully meets the requirements of semiconductor processes, and is easy to process, saving material processing costs. Furthermore, the acoustic impedance coefficient of PI material is 3 MRayi, which has a high degree of matching with the acoustic impedance of the gas, making it more conducive to sound wave propagation. Compared with the existing metal detection chamber with an acoustic impedance coefficient of about 45 MRayi, the acoustic signal intensity of the PI material detection chamber can be increased by 15 times, which is more conducive to the transmission of sound wavelength over distance, enabling the electrical device to detect the time of flight more accurately and with higher precision.

[0048] An opening 24 is formed on the side wall 23 of the detection chamber. This is necessary for both the demolding of the injection-molded detection chamber and the entry and exit of the gas to be detected. The entry and exit of the gas to be detected should be understood as utilizing the diffusivity of the gas to create a relatively stable state of uniform concentration within the detection chamber, rather than a gas flow state.

[0049] The forming cavity is formed by a forming cavity sidewall 21a extending upward from the edge of the transmission wall and a forming cavity boss 21b, and is arranged back-to-back with the detection chamber and integrally formed with the detection chamber.

[0050] Transducer 50, comprising piezoelectric ceramic material or ceramic piezoelectric material, is disposed outside the detection chamber and adjacent to the transmission wall 21, and is encapsulated within a molded cavity using impedance-matching sealant. Transducer 50 is used to emit ultrasonic waves and receive ultrasonic waves emitted from it, which pass sequentially through the transmission wall 21 and the detected gas, are reflected by the reflection wall 22, and then pass through the detected gas and the transmission wall 21. Piezoelectric ceramic material or ceramic piezoelectric material refers to functional ceramics with PbTiO3-PbZrO3 system (PZT) as the main component, exhibiting piezoelectric properties through high-temperature sintering and polarization processes, realizing the interconversion of mechanical energy and electrical energy. Its main component is Pb(Zr,Ti)O3 solid solution, with a sintering temperature exceeding 1200℃, possessing both positive and reverse piezoelectric effects and dielectric properties. Transducer 50 serves to transmit and receive ultrasonic signals. Its diameter is between 25-30 mm. To achieve optimal acoustic coupling efficiency and improve concentration detection accuracy, this size design ensures that the near-field acoustic wave length is compatible with the instrument's operating environment and the length of the detection cavity. Because transducer 50 is made of piezoelectric ceramic material, it is also commonly referred to as a piezoelectric transducer.

[0051] Preferably, the piezoelectric ceramic material of the transducer can be PZT-5A or PZT-5H.

[0052] The acoustic impedance range of the sealant used for sealing the transducer 50 can be 0.11-3 MRayi. This application does not specify the specifications of the sealant, but only requires that it meets the acoustic impedance range.

[0053] See Figures 2 to 5 The sealing sleeve module 30 has a sleeve container shape that matches the shape of the detection module 20, for accommodating and sealing the detection chamber, including an inlet and an outlet in fluid communication with the detection chamber. The sealing sleeve module 30 may include a circular sleeve base plate 32, a sleeve sidewall 31 extending upward from the edge of the sleeve base plate 32, and an inlet 33 and an outlet 34 symmetrically arranged on the sleeve sidewall 31. Although not shown in the figures, as those skilled in the art will know, the inlet 33 and outlet 34 include fittings suitable for connection to a gas pipeline, such as VCRs (Vacuum Coupling Retainers) and compression fittings. The airflow direction of the sealing sleeve is distributed at a 90-degree angle to the opening 24 of the detection chamber of the single-lens reflex integrated detection module, and the air inlet 33 and air outlet 34 of the sealing sleeve module 30 are located below the opening 24 of the detection chamber. This simple assembly design can avoid the influence of airflow velocity on the sound wave flight time, and thus avoid the influence of gas velocity on the detection concentration.

[0054] like Figure 6 As shown, the controller module 10 includes an electrical module 12, a display module 11, and a driver board 40.

[0055] The electrical module 12 includes a communication board, a power supply board, and a main control board (not specifically shown). On one hand, the electrical module 12 can control the drive board 40, thereby causing the transducer 50 to emit ultrasonic waves of a predetermined wavelength. On the other hand, the electrical module 12 can receive emitted and reflected ultrasonic wave signals from the transducer 50, and convert these signals into electrical signals representing the concentration of the detected gas using a predetermined algorithm. In other words, the electrical module 12 can demodulate the gas concentration information from the emitted and reflected ultrasonic wave signals. The communication board of the electrical module 12 can communicate with the display module 11, and may also communicate simultaneously with the system controller of the detected gas. Figure 6 The electrical module 12 is only schematically shown, without specifically showing, or further defining, the communication board, power board, and main control board that constitute the electrical module 12. This is because the communication board, power board, and main control board can be integrated into a single circuit board, or into an integration of 2-4 circuit boards. Those skilled in the art can customize the communication, power supply, and main board according to actual needs.

[0056] The display module 11 has a display screen, receives an electrical signal representing the concentration of the detected gas from the electrical module 12, and displays it as a digital image on the display screen.

[0057] The driver board 40 is positioned below the electrical module, that is, above the transducer 50, and drives the transducer 50 to emit ultrasonic waves. The transducer 50 is driven by the electrical module 12 of the controller module 10.

[0058] The detection module 20, sealing sleeve module 30, and controller module 10 are modular components, and the detection module 20 is compatible with and detachably connected to the sealing sleeve module 30 and the controller module 10. The transducer, detection chamber, and molding chamber are integrated into a single detection module; the display module, electrical modules (communication board, power board, and main control board), and drive board are integrated into a single controller module; and the sealing sleeve module is a separate module. Therefore, the detection module, sealing sleeve module, and controller module are all modular components, and the detection module is compatible with and detachably connected to the sealing sleeve module and the controller module. This allows for convenient handling when any module needs repair or replacement, improving maintenance and repair efficiency.

[0059] According to embodiments of this application, the predetermined algorithm program may include the following formula: T = 4Z1 * Z2 / (Z1 + Z2)^2 Where T is the sound intensity transmittance, Z1 is the gas acoustic impedance, and Z2 is the solid medium acoustic impedance.

[0060] The acoustic impedance coefficient of PI material is 3MRayi, which has a high degree of matching with the acoustic impedance of gas, making it more conducive to sound wave propagation. The sound signal intensity can be increased by 15 times, which is more conducive to the transmission of sound wavelength over distance. This allows electrical appliances to detect flight time more accurately and with higher precision.

[0061] Based on the above calculation using the acoustic intensity transmittance formula and the analysis above, it can be seen that the acoustic impedance coefficient of PI material (that is, a solid medium with acoustic impedance of Z2) is 3Mrayi, and the acoustic signal intensity (T) calculated by the above formula is increased by 15 times, which is more conducive to the transmission of sound wavelength over distance, and can make the flight time detected by electrical appliances more accurate and precise.

[0062] Using a single-reflection design, the sound wave transmission path within a limited space is doubled, directly doubling the minimum concentration detection line. According to embodiments of this application, the predetermined algorithm program may further include the following formula: Formula for calculating the speed of sound in a gas: C=d / t Gas concentration calculation formula: X∝1 / C Where C is the speed of sound in the gas, d is the effective length of the acoustic cavity, t is the flight time, and X is the gas concentration.

[0063] The above analysis shows that by using a single-reflection design, doubling the effective length (d) of the acoustic cavity in the sound wave transmission path within a limited space doubles the gas sound velocity (C), while halving the gas concentration (X). Therefore, we can conclude that the minimum concentration detection line is directly reduced by half.

[0064] Using a single-lens resonator design, the transmitting and receiving components use the same transducer with no difference in resonant points. This effectively avoids functional problems such as low coupling efficiency, severe self-emission, and poor consistency caused by the difference in resonant frequencies of multiple transducers, and eliminates the need for transducer selection during system assembly.

[0065] The transducer and modulation frequency are designed based on hydrogen carrier gas at a high temperature of 150℃. The near-field acoustic wave length is compatible with the reflective working distance. The high acoustic coupling efficiency improves the detectability of acoustic signal strength. It has high compatibility with working environment and high compatibility with the types of detectable gases.

[0066] According to embodiments of this application, the predetermined algorithm program may further include the following formula: Near-field sound wave length calculation formula: N=D^2*f / (4*C) Where N is the near-field acoustic wave length, D is the diameter of the transducer piezoelectric ceramic, f is the driving frequency, and C is the gas velocity.

[0067] The above analysis shows that by designing the transducer and modulation frequency using hydrogen carrier gas at a high temperature of 150℃, the near-field acoustic wave length is compatible with the working distance of reflective devices, and the high acoustic wave coupling efficiency improves the detectability of the acoustic wave signal strength. Calculations using the above near-field acoustic wave length formula demonstrate that the gas concentration detection device according to the embodiments of this application has high compatibility with various operating environments and high compatibility with a wide range of detectable gases.

[0068] According to embodiments of this application, the surface roughness of the transmission wall 21 and the reflection wall 22 of the detection chamber can be less than or equal to 0.4. The surface roughness of the transmission wall 21 and the reflection wall 22 of the detection chamber depends on the injection molding process conditions and the properties of PI itself. A surface roughness of less than or equal to 0.4 is beneficial for reducing the intensity of scattered sound, thereby improving the accuracy and precision of the concentration detection.

[0069] According to embodiments of this application, the reflective wall 22 of the detection chamber may include metal. Depending on practical design needs, those skilled in the art may selectively replace all or part of the reflective wall 22 with metal without affecting the performance of the gas concentration detection device for detecting binary gas concentration according to embodiments of this application. According to embodiments of this application, the reflective wall 22 of the detection chamber may have a coating. Preferably, the coating may include a gold plating or a T6 aluminum alloy-diamond carbon film composite coating.

[0070] According to an embodiment of this application, preferably, the distance between the transmission wall 21 and the reflection wall 22 of the detection chamber can be between 20-30 mm.

[0071] According to an embodiment of this application, the detection chamber may include a molded cavity extending upward from the edge of the transmission wall 21 to accommodate the transducer 50. The molded cavity is enclosed by the side walls of the molded cavity, and the transducer 50 is encapsulated within the molded cavity using an impedance-matching sealant. According to an embodiment of this application, preferably, the transducer 50 may be disc-shaped, with a diameter between 25-30 mm.

[0072] According to an embodiment of this application, the design environment of the transducer 50 can be a driving frequency of 500K-5MHz for hydrogen at a temperature of 150°C.

[0073] According to embodiments of this application, the air inlet and outlet of the sealing sleeve module 30 may include a vacuum coupling retainer (VCR) and / or a ferrule fitting pipe fitting.

[0074] According to an embodiment of this application, the material of the sealing sleeve of the sealing sleeve module 30 may include 316L.

[0075] According to embodiments of this application, the gas concentration detection device for detecting binary gas concentration is suitable for detecting binary gases including carrier gases H2, N2, He or Ar, and active gases SiH4, DCS, NH3, PH3, B2H6, AsH3, GeH4, WF6, Ga(CH3)3 or Si(OC2H5)4.

[0076] According to embodiments of this application, a gas concentration detection device for detecting binary gas concentration is suitable for detecting the gas concentration in a gas supply system for semiconductor thin film processes.

[0077] According to embodiments of this application, semiconductor thin film processes may include MOCVD, PECVD, HDPCVD, and ALD processes.

[0078] The above description is merely a specific implementation of the embodiments of this application, but the protection scope of the embodiments of this application is not limited thereto. Any changes or substitutions within the technical scope disclosed in the embodiments of this application should be covered within the protection scope of the embodiments of this application. Therefore, the protection scope of the embodiments of this application should be determined by the protection scope of the claims.

Claims

1. A gas concentration detection device for detecting the concentration of a binary gas, characterized in that, include: Detection module, including The detection chamber has a cylindrical detection space, including a circular transmission wall, a reflective wall arranged face-to-face and parallel to the transmission wall, and a side wall disposed between and connecting the transmission wall and the reflective wall. The side wall has an opening for the gas to be detected to enter and exit. A forming cavity extends upward from the edge of the transmission wall, is disposed back-to-back with the detection chamber, and is integrally formed with the detection chamber. A transducer, comprising a piezoelectric ceramic material, is disposed in the molding cavity and adjacent to the transmission wall for emitting ultrasonic waves and receiving ultrasonic waves emitted therefrom, transmitted through the transmission wall and the gas being detected, and reflected back by the reflection wall. The transducer is encapsulated in the molding cavity with an impedance-matched sealant. A sealing sleeve module has a sleeve container shape that matches the shape of the detection module for accommodating and sealing the detection chamber, including an air inlet and an air outlet that are in fluid communication with the detection chamber; as well as Controller module, including The electrical module, including a communication board, a power supply board, and a main control board, receives transmitted and reflected ultrasonic signals from the transducer, and converts these signals into an electrical signal representing the concentration of the detected gas using a predetermined algorithm. The display module has a display screen, receives an electrical signal representing the concentration of the detected gas output from the electrical module, and displays it as a digital image on the display screen. A drive board is located below the electrical module and drives the transducer to emit ultrasonic waves according to the instructions of the electrical module. The detection module, the sealing sleeve module, and the controller module are modular components, and the detection module and the sealing sleeve module, as well as the detection module and the controller module, are matched with each other and detachably connected.

2. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The predetermined algorithm program includes the following formulas: T = 4Z1 * Z2 / (Z1 + Z2)^2 Where T is the sound intensity transmittance, Z1 is the gas acoustic impedance, and Z2 is the solid medium acoustic impedance. C=d / t and X∝1 / C Where C is the speed of sound in the gas, d is the effective length of the acoustic cavity, t is the flight time, and X is the gas concentration; and N = D^2 * f / (4 * C) Where N is the near-field acoustic wave length, D is the diameter of the transducer piezoelectric ceramic, f is the driving frequency, and C is the gas velocity.

3. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The detection chamber is integrally formed from polyimide (PI) material.

4. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The piezoelectric ceramic material of the transducer is PZT-5A or PZT-5H.

5. The gas concentration detection device for detecting binary gas concentration as described in claim 3, characterized in that, The surface roughness of the transmission wall and the reflection wall of the detection chamber is less than or equal to 0.

4.

6. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The reflective wall of the detection chamber has a coating.

7. The gas concentration detection device for detecting binary gas concentration as described in claim 6, characterized in that, The coating includes a gold coating or a T6 aluminum alloy-diamond carbon film composite coating.

8. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The distance between the transmission wall and the reflection wall of the detection chamber is between 20-30 mm.

9. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The acoustic impedance of the sealant is in the range of 0.11-3MRayi.

10. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The transducer is disc-shaped with a diameter between 25-30 mm.

11. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The transducer is designed for use with hydrogen at 150°C and a driving frequency of 500K-5MHz.

12. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The air inlet and outlet of the sealing sleeve module include pipe joints for vacuum coupling retainers and / or ferrule fittings.

13. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The sealing sleeve of the sealing sleeve module is made of 316L material.

14. The gas concentration detection device for detecting binary gas concentration as described in claim 3, characterized in that, The acoustic impedance coefficient of the polyimide (PI) material is 3MRayi.

15. The gas concentration detection device for detecting binary gas concentration as described in claim 1, characterized in that, The gas concentration detection device for detecting binary gas concentration is suitable for detecting binary gases including carrier gases H2, N2, He or Ar, and active gases SiH4, DCS, NH3, PH3, B2H6, AsH3, GeH4, WF6, Ga(CH3)3 or Si(OC2H5)4.

16. The gas concentration detection device for detecting binary gas concentration as described in claim 15, characterized in that, The gas concentration detection device for detecting binary gas concentration is suitable for detecting the gas concentration in the gas supply system of semiconductor thin film processes.

17. The gas concentration detection device for detecting binary gas concentration as described in claim 16, characterized in that, The semiconductor thin film processes include MOCVD, PECVD, HDPCVD, and ALD processes.

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