Detachable leakage detection device of semiconductor equipment and leakage detection method

Abstract

The invention relates to a detachable leakage detection device and a leakage detection method for semiconductor equipment, and the device comprises a main frame; the conversion module comprises a conversion cavity; the laser transmitter is used for transmitting laser to the conversion cavity to generate a photoacoustic signal; the conversion device is used for receiving the photoacoustic signal and converting the photoacoustic signal into an electric signal; the filtering module is used for filtering the characteristic gas entering the conversion cavity through the gas inlet pipeline; and the exhaust module controls the on-off of the exhaust pipeline. The leakage detection method comprises the following steps: introducing characteristic gas at a to-be-detected point position of semiconductor equipment into a conversion cavity through a gas inlet pipeline; controlling a laser emitter to emit laser; the characteristic gas in the conversion cavity absorbs the laser to generate vibration, and a photoacoustic signal is generated; converting the photoacoustic signal into an electric signal; converting the electrical signal into a gas concentration; setting a threshold value; and when the gas concentration is greater than the threshold value, judging that the to-be-detected point of the semiconductor equipment leaks. The system can adapt to multiple monitoring points and is convenient to maintain due to the modular design.

Description

Technical Field

[0001] This invention relates to the field of semiconductor testing technology, and in particular to a detachable leakage detection device and leakage detection method for semiconductor equipment. Background Technology

[0002] In the semiconductor integrated circuit manufacturing process, the use of special gases (such as SiH4, PH3, AsH3, HF, etc.) is extremely critical, but most of these gases are toxic, flammable, and explosive. Leaks of these gases not only pose a serious threat to production safety, but more importantly, they can lead to a series of adverse consequences, including decreased chip quality and equipment damage. Therefore, real-time, high-sensitivity detection of special gas leaks in semiconductor equipment is crucial.

[0003] In existing technologies, commonly used gas leak detection methods in the semiconductor industry include electrochemical sensors, catalytic combustion sensors, and traditional spectroscopic analysis techniques. However, these methods have many limitations. For example, electrochemical sensors have a short lifespan (typically requiring replacement every six months to a year), high maintenance costs, frequent maintenance, monitoring blind spots, poor selectivity, and susceptibility to cross-interference, leading to a high false alarm rate. Catalytic combustion sensors have response speeds limited by the sampling pipeline, resulting in long overall response times (often tens of seconds), and require periodic shutdowns for on-site calibration, impacting equipment uptime. While traditional spectroscopic analysis techniques offer high sensitivity and selectivity, current technologies are mostly concentrated in large laboratory analytical instruments, which are complex, bulky, and expensive. Furthermore, they lack engineering and modular design tailored to the needs of semiconductor industrial environments, making it difficult to meet the rapid response requirements of cleanrooms, multi-monitoring points, and environments with high vibration and noise.

[0004] Therefore, it is necessary to provide a new detachable leakage detection device and leakage detection method for semiconductor devices to solve the above-mentioned problems existing in the prior art. Summary of the Invention

[0005] The technical problem to be solved by this application is how to provide a detachable leakage detection device and leakage detection method for semiconductor devices that can be adapted to multiple monitoring points and whose modular design facilitates maintenance.

[0006] To address the aforementioned technical problems, according to embodiments of this application, a detachable leakage detection device for semiconductor equipment is provided, comprising: a main frame detachably disposed on the semiconductor equipment; a conversion module disposed on the main frame; the conversion module includes a conversion cavity, the side wall of which is provided with an inlet pipe and an exhaust pipe, the inlet pipe being connected to a test point so that a characteristic gas in the test point enters the conversion cavity via the inlet pipe and exits via the exhaust pipe; a laser emitter disposed on the main frame and placed on one side of the conversion cavity, for emitting a laser into the conversion cavity so that the laser enters the conversion cavity and is absorbed by the characteristic gas, generating a photoacoustic signal; a conversion device disposed on the side wall of the conversion cavity, for receiving the photoacoustic signal and converting the photoacoustic signal into an electrical signal; a filter module disposed on the inlet pipe for filtering the characteristic gas entering the conversion cavity via the inlet pipe; and an exhaust module disposed on the exhaust pipe for controlling the opening and closing of the exhaust pipe.

[0007] According to an embodiment of this application, both ends of the conversion cavity are provided with light-transmitting elements, which are transparent, so that the laser enters the conversion cavity after passing through the light-transmitting elements.

[0008] According to an embodiment of this application, the diameter of the end of the conversion cavity is larger than the diameter of the middle part of the conversion cavity so that both ends of the conversion cavity form anechoic cavities; the light-transmitting element is disposed in the anechoic cavity and covers the end of the conversion cavity; a laser detector is provided at the end of the conversion cavity to receive laser light passing through the conversion cavity.

[0009] According to an embodiment of this application, a collimating lens is also included, which is disposed between the anechoic cavity and the laser emitter, so that the laser enters the conversion cavity after passing through the collimating lens and the anechoic cavity.

[0010] According to an embodiment of this application, the conversion module further includes a reference gas chamber and a reference detector; the reference gas chamber is filled with a reference gas; the laser emitted by the laser emitter passes through the reference gas chamber and is received by the reference detector to form a reference signal.

[0011] According to an embodiment of this application, the conversion cavity is cylindrical, and the volume of the conversion cavity is less than or equal to 5 cm³.

[0012] According to an embodiment of this application, the filtration module includes a heated filtration device and a particulate filtration device. The heated filtration device is disposed between the particulate filtration device and the conversion chamber, so that gas passes through the particulate filtration device and the heated filtration device in sequence before entering the conversion chamber.

[0013] A leakage detection method for semiconductor devices, applied to the aforementioned detachable leakage detection device, includes the following steps: introducing a characteristic gas at the test point of the semiconductor device into a conversion cavity via an inlet pipe; controlling the laser emitter to emit a laser, so that the laser passes through the conversion cavity and irradiates the laser detector; the characteristic gas in the conversion cavity absorbs the laser and vibrates, generating a photoacoustic signal; collecting the photoacoustic signal using a conversion device and converting the photoacoustic signal into an electrical signal; converting the electrical signal into a gas concentration; setting a threshold; and determining that a leakage has occurred at the test point of the semiconductor device when the gas concentration is greater than the threshold.

[0014] According to an embodiment of this application, controlling the laser emitter to emit laser light so that the laser light passes through the conversion cavity and then irradiates the laser detector includes controlling the laser emitter to emit laser light so that a portion of the laser light passes through one of the optical fibers and enters the conversion cavity and irradiates the laser detector; the remaining portion of the laser light passes through another optical fiber and enters the reference gas chamber and irradiates the reference detector.

[0015] According to an embodiment of this application, converting the electrical signal into a gas concentration includes: calibrating the electrical signal based on the characteristic absorption peak amplitude of the characteristic gas obtained from the reference detector; and converting the calibrated electrical signal amplitude into the gas concentration.

[0016] By adopting the above technical solution, based on photoacoustic spectroscopy, a laser excites a characteristic gas to generate a photoacoustic signal. This signal is captured and converted into an electrical signal by a conversion device. After digital phase-locked loop amplification and compensation processing, it is converted into a gas concentration value, which is compared with a preset threshold to determine whether a leak has occurred at the test point of the semiconductor equipment. The device also features a modular design, with the main frame detachable and installable on the semiconductor equipment, adapting to the detection needs of different characteristic gases. It achieves high-sensitivity detection, while its modular design facilitates maintenance and replacement. Furthermore, the laser wavelength is locked and calibrated via a reference gas chamber, ensuring long-term stability and measurement accuracy. It is suitable for leak monitoring of various toxic and harmful gases in semiconductor processes, thereby ensuring production safety and environmental quality. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the main structure of a detachable leak detection device according to an embodiment of the present invention.

[0018] Figure 2 This is a schematic diagram of the structure of a conversion module according to an embodiment of the present invention.

[0019] Figure 3 This is a step diagram of a detachable leak detection method according to an embodiment of the present invention.

[0020] Figure label:

[0021] 100. Main frame; 200. Conversion module; 210. Conversion cavity; 211. Light-transmitting element; 220. Air intake pipe; 230. Exhaust pipe; 240. Silencing cavity; 250. Reference chamber; 260. Reference detector; 270. Laser emitter; 280. Conversion device; 300. Filter module; 310. Heating filter device; 320. Particulate filter device; 400. Air extraction module; 500. Laser detector; 600. Collimating lens. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. Unless otherwise defined, the technical or scientific terms used herein should have the ordinary meaning understood by those skilled in the art. 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.

[0023] The following is combined with Figures 1-3 The specific embodiments of the present invention will be further described in detail below.

[0024] An embodiment of the present invention provides a detachable leakage detection device for semiconductor equipment. The detachable leakage detection device is used to be installed on the semiconductor equipment to detect whether a leakage has occurred at the corresponding test point in the semiconductor equipment. Specifically, the detachable leakage detection device includes a main frame 100, a conversion module 200, a laser emitter 270, a conversion device 280, a filter module 300, and an air extraction module 400.

[0025] In some embodiments, the main frame 100 is detachably disposed on the semiconductor device, and different main frames 100 can detect different characteristic gases to determine whether the corresponding characteristic gas has leaked; the detachable connection method can be bolt connection, snap-fit ​​or plug-in connection with concave and convex fit, etc., and there is no specific limitation here, as long as the detachable connection can be achieved. The conversion module 200 is located inside the main frame 100 to facilitate connection between the conversion module 200 and the semiconductor device. The conversion module 200 includes a conversion chamber 210. The side wall of the conversion chamber 210 is provided with an inlet pipe 220 and an exhaust pipe 230. The inlet pipe 220 is used to communicate with the test point so that the characteristic gas of the test point enters the conversion chamber 210 through the inlet pipe 220 and is discharged through the exhaust pipe 230. During the leak detection process, the characteristic gas of the test point can enter the conversion chamber 210 through the inlet pipe 220, be detected in the conversion chamber 210, and be discharged through the exhaust pipe 230. This allows for the detection of leaks in the semiconductor device without affecting the gas discharge of the semiconductor device. One end of the intake pipe 220 is connected to the conversion chamber 210, and the other end is connected to the exhaust port of the process chamber, which facilitates the detection of the content of the corresponding characteristic gas at the test point of the semiconductor equipment, so as to determine whether the semiconductor equipment has leaked.

[0026] In some embodiments, a laser emitter 270 is mounted on the main frame 100 and positioned on one side of the conversion cavity 210, with a gap between them, for emitting laser light into the conversion cavity 210. The laser light emitted by the laser emitter 270 enters the conversion cavity 210 and is absorbed by the characteristic gas inside the conversion cavity 210, generating a photoacoustic signal. Specifically, the conversion cavity 210 has an entrance window and an exit window at both ends. The laser emitter 270 can emit laser light towards the entrance window, and the laser light emitted by the laser emitter 270 irradiates the entrance window and then irradiates the interior of the conversion cavity 210. When the test point of the semiconductor device leaks, the characteristic gas inside the conversion cavity 210 absorbs the energy of the laser light irradiating the conversion cavity 210, thereby generating a photoelectric signal to facilitate the subsequent judgment process.

[0027] In some embodiments, the conversion device 280 is disposed on the side wall of the conversion cavity 210, and is used to receive photoacoustic signals and convert them into electrical signals. Specifically, during laser irradiation, the wavelength of the laser is locked to the absorption band of a specific characteristic gas. When the laser irradiates the conversion cavity 210, the corresponding characteristic gas absorbs the laser and undergoes periodic thermal expansion, generating a pressure wave of the same frequency, i.e., a photoacoustic signal. The conversion device 280 can collect this pressure wave, thereby converting it into an electrical signal and outputting it. Specifically, the conversion device 280 is a MEMS microphone.

[0028] In some specific embodiments, two conversion devices 280 are provided, arranged radially symmetrically within the conversion cavity 210. When the acoustic wave arrives, the common-mode interference is in phase, while the photoacoustic signal is out of phase. That is, external interference such as vibration and electromagnetic noise propagates from the outside into the conversion cavity 210, entering the two conversion devices 280 with the same polarity (positive and negative directions are consistent). The acoustic wave generated by the gas absorbing the laser originates from the center of the cavity. The two microphones are symmetrically positioned, and the acoustic waves arrive with opposite polarities (one positive and one negative). After processing by a differential amplifier, the signals from the two microphones are subtracted. Since the common-mode interference signal is in phase at the two microphones, it is canceled out after subtraction; while the photoacoustic signal is out of phase at the two microphones, the amplitude is doubled after subtraction, improving the signal-to-noise ratio and thus enhancing the detection accuracy.

[0029] In some embodiments, the filter module 300 is located in the air inlet pipe 220 to filter the characteristic gas entering the conversion chamber 210 through the air inlet pipe 220; the air extraction module 400 is an air extraction pump and is located in the exhaust pipe 230 to extract air so that the characteristic gas of the test point enters the conversion chamber 210 through the air inlet pipe 220 and is discharged from the exhaust pipe 230, while the on / off state of the exhaust pipe 230 can be controlled.

[0030] In some embodiments, the main frame 100 is also provided with a display module, which has a digital signal processor to modulate the wavelength of the laser emitter 270. It is well known to those skilled in the art that the display module has a digital signal processor, and will not be described in detail here.

[0031] In some specific embodiments, different harmful gases, such as SiH4, PH3, AsH3, or HF, are used in semiconductor processing. These gases are used in different stages, stored in different locations, and have different leakage scenarios. For example, SiH4 gas is used in the CVD deposition stage, and leakage will affect the deposition equipment; PH3 gas is used in the ion implantation doping stage, and leakage will affect the implantation equipment; AsH3 gas is used in the epitaxial growth stage, and leakage will affect the epitaxial equipment; HF gas is used in the etching and cleaning stage, and leakage will affect the cleaning equipment. Therefore, corresponding leakage detection devices are needed for leaks at different locations, as a single leakage detection device cannot be adapted to detect leaks at different test points. Meanwhile, different harmful gases have different absorption peaks, and a single laser cannot be adapted to each harmful gas. Therefore, the laser emitters 270 in different main racks 100 emit lasers with different wavelengths. Specifically, the wavelengths of the lasers emitted by the laser emitters 270 in different main racks 100 are adapted to the corresponding characteristic gases, thus facilitating the detection of different characteristic gases. For example, when it is necessary to detect whether SiH4 gas is leaking, the wavelength of the laser emitted by the corresponding laser emitter 270 in the main rack 100 is adapted to the absorption peak of SiH4 gas. During the detection process, the main rack 100 is placed at the corresponding test point to detect whether SiH4 gas is leaking. When it is necessary to detect whether AsH3 gas is leaking, the wavelength of the laser emitted by the corresponding laser emitter 270 in the main rack 100 is adapted to the absorption peak of AsH3 gas. During the detection process, the main rack 100 is placed at the corresponding test point to detect whether AsH3 gas is leaking.

[0032] In some embodiments, both ends of the conversion cavity 210 are provided with light-transmitting elements 211, which are transparent so that the laser light enters the conversion cavity 210 after passing through the light-transmitting elements 211. Specifically, the light-transmitting element 211 closer to the laser emitter 270 forms an incident window, and the light-transmitting element 211 farther from the laser emitter 270 forms an exit window. During the detection process, the laser light emitted by the laser emitter 270 irradiates the incident window, passes through the incident window into the conversion cavity 210, and then exits through the exit window, so as to facilitate the detection process.

[0033] In some embodiments, the diameter of the end of the conversion cavity 210 is larger than the diameter of the middle part of the conversion cavity 210 so that both ends of the conversion cavity 210 form anechoic cavities 240; the light-transmitting element 211 is disposed in the anechoic cavity 240 and covers the end of the conversion cavity 210; a laser detector 500 is provided at the end of the conversion cavity 210 to receive the laser light passing through the conversion cavity 210. Specifically, during the detection process, the laser light emitted by the laser emitter 270 first passes through the anechoic cavity 240 at the entrance window and irradiates the entrance window, then enters the conversion cavity 210 after passing through the entrance window, irradiates the exit window after passing through the conversion cavity 210, and then irradiates the laser detector 500 after passing through the anechoic cavity 240 at the exit window, and is received by the laser detector 500. More specifically, to reduce the background noise generated by laser absorption and the acoustic noise caused by the sound wave transmission characteristics of the light-transmitting element 211 in the conversion cavity 210, silencing cavities 240 are set at both ends of the conversion cavity 210. The silencing cavities 240 achieve acoustic impedance mismatch and thermal / fluid field buffering through abrupt changes in geometric cross-section, isolating window thermal noise outside the reaction area of ​​the conversion cavity 210, while providing an optical window mounting position to ensure the stability of the photoacoustic signal within the conversion cavity 210. Specifically, for example, during detection, when the laser passes through the light-transmitting element 211, the element expands due to heat, generating false photoacoustic signals. The silencing cavities 240 enlarge the volume of the light-transmitting element, moving it away from the central gas region of the conversion cavity 210, allowing heat to dissipate to the walls of the silencing cavities 240, thereby reducing thermal disturbance to the central gas. The laser detector 500 can determine whether the laser position is aligned and whether the laser reaches the laser detector 500 normally, thus determining the continuity of the optical path.

[0034] In some embodiments, the detachable leak detection device further includes a collimating lens 600, which is disposed between the anechoic cavity 240 and the laser emitter 270, so that the laser light enters the conversion cavity 210 after passing through the collimating lens 600 and the anechoic cavity 240. Specifically, since the laser light emitted by the laser emitter 270 has a certain divergence angle, the collimating lens 600 is placed between the anechoic cavity 240 and the laser emitter 270 at the incident window to make the laser light parallel, thereby making the laser light entering the conversion cavity 210 parallel, which facilitates the subsequent detection process.

[0035] In some embodiments, the conversion module 200 further includes a reference gas chamber 250 and a reference detector 260; the reference gas chamber 250 is filled with a reference gas; the laser emitted by the laser emitter 270 passes through the reference gas chamber 250 and is received by the reference detector 260 to form a reference signal. Specifically, the reference gas chamber 250 has an inflation port, through which a corresponding characteristic gas can be injected into the reference gas chamber 250; at the same time, the end of the laser emitter 270 has an optical fiber, and the optical fiber forms two branches through a Y-type optical fiber coupler, so that the laser emitted by the laser emitter 270 can enter the conversion cavity 210 and the reference gas chamber 250 respectively; specifically, the reference detector 260 is used to receive the laser passing through the reference gas chamber 250 to detect its laser power, and lock the laser wavelength based on the characteristic absorption peak of the reference gas chamber 250, while also providing the signal amplitude at a known concentration, which facilitates the subsequent judgment process.

[0036] In some embodiments, the conversion cavity 210 is cylindrical, and its volume is less than or equal to 5 cm³. Specifically, the cylindrical shape allows for sufficient overlap between the laser and the gas, facilitating the symmetrical installation of dual microphones for differential noise reduction. The volume of less than or equal to 5 cm³ enables the characteristic gas within the conversion cavity 210 to be replaced in a short time, achieving rapid response. Simultaneously, the small volume results in high laser power density and low acoustic mode density, reducing background noise while generating a sufficiently strong photoacoustic signal. It also provides a spatial basis for the modular design of the entire sensor box.

[0037] In some embodiments, the filter module 300 includes a heated filter device 310 and a particulate filter device 320. The heated filter device 310 is disposed between the particulate filter device 320 and the conversion chamber 210, so that the gas passes through the particulate filter device 320 and the heated filter device 310 in sequence before entering the conversion chamber 210.

[0038] In some specific embodiments, the particulate filter 320 serves as the first physical barrier in the gas path, capable of physical interception, i.e., filtering out solid particles such as dust, metal particles, and fibers from the air, preventing these contaminants from entering the conversion chamber 210. The particulate filter 320 includes a housing and filter media disposed within the housing. The filter media of the particulate filter 320 can be made of glass fiber or polytetrafluoroethylene (PTFE) membrane. Glass fiber has a porous network structure formed by interwoven fibers, with uniform pores, enabling efficient capture of submicron-sized particles, good temperature resistance, and low cost. PTFE membrane has excellent chemical inertness, resisting corrosion from almost all harmful characteristic gases, while also exhibiting excellent hydrophobicity, effectively blocking liquid water droplets. Its surface filtration mechanism also makes it difficult for particles to become embedded, helping to reduce pressure drop. The housing of the particulate filter 320 is made of stainless steel to ensure structural strength and corrosion resistance. Openings in the housing allow gas to pass through the filter media, as is known to those skilled in the art and will not be elaborated upon here.

[0039] In some specific embodiments, the heated filtration device 310 is capable of chemical adsorption and dynamic protection. It primarily removes gaseous interfering substances, especially water vapor and organic oil vapors, while preventing measurement delays and distortions caused by adsorption / desorption effects of the target gas molecules. It also includes a housing and filter media disposed within the housing; the filter media includes modified activated carbon and hydrophobic molecular sieves; the modified activated carbon has a very large specific surface area, effectively adsorbing organic oil vapors and some acidic gases (modified activated carbon is obtained by physical or chemical treatment of activated carbon, a method known to those skilled in the art and not described in detail here). By modifying the surface according to the properties of the target gas, its selectivity can be optimized, reducing competitive adsorption of the target gas. The pore structure of the hydrophobic molecular sieve preferentially adsorbs organic matter rather than water molecules, thus facilitating the removal of oily contaminants in environments with fluctuating humidity. The housing is made of stainless steel and has a heater. The heater uses a metal thin-film heating element etched onto a ceramic plate or stainless steel tube to facilitate heating. The housing has openings to allow gas to pass through the filter media, a method known to those skilled in the art and not described in detail here.

[0040] This application also discloses a leakage detection method for semiconductor devices. The leakage detection method is applied to the aforementioned detachable leakage detection device and includes the following steps: S1. The characteristic gas at the test point of the semiconductor device is introduced into the conversion chamber 210 through the inlet pipe 220. Specifically, during the detection process, the leakage detection device is placed at the test point of the semiconductor device, wherein the gas extraction module 400 starts to extract gas, so that the gas at the test point enters the inlet pipe 220 and enters the conversion chamber 210 through the inlet pipe 220.

[0041] S2. Control the laser emitter 270 to emit a laser, so that the laser light passes through the conversion cavity 210 and irradiates the laser detector 500; the characteristic gas in the conversion cavity 210 absorbs the laser light and vibrates, generating a photoacoustic signal; specifically, control the laser emitter 270 to emit a laser of a specific wavelength, which is usually selected to match the absorption characteristics of the characteristic gas to ensure that the characteristic gas in the conversion cavity 210 can effectively absorb the laser energy; when the laser light irradiates the conversion cavity 210, the characteristic gas in the conversion cavity 210 absorbs the laser energy of the specific wavelength, causing the energy level transition of the gas molecules, causing the gas molecules to transition from the ground state to the excited state; after absorbing the laser energy, the gas molecules release energy when they return from the excited state to the ground state. This energy is transferred to the surrounding gas molecules in the form of heat, causing the gas molecules to expand thermally. This thermal expansion generates local pressure changes, producing pressure waves, i.e., sound waves. The sound waves are detected by the conversion device 280, forming a photoacoustic signal. The intensity of the photoacoustic signal is proportional to the concentration of the characteristic gas. Therefore, the concentration of the gas can be determined by measuring the intensity of the photoacoustic signal. The laser detector 500 receives the laser light after passing through the conversion cavity 210 and measures its transmitted light intensity. The change in transmitted light intensity can reflect the degree of gas absorption. Because the more laser light is absorbed by the gas, the weaker the transmitted light intensity, thereby monitoring the power stability of the laser emitter 270 and diagnosing problems in the optical path (such as window contamination or laser aging).

[0042] S3. The conversion device 280 collects photoacoustic signals and converts them into electrical signals. Specifically, the conversion device 280 collects photoacoustic signals, that is, the diaphragm of the MEMS microphone directly senses the periodic pressure wave, the capacitance changes, and the output is an alternating voltage with the same frequency as the pressure wave, thereby converting the photoacoustic signal into an electrical signal.

[0043] S4. Convert the electrical signal into gas concentration; S5. Set the threshold value; the leakage threshold value varies for different characteristic gases, and there is no specific limit here. In the actual detection process, the value should be set according to the type of characteristic gas.

[0044] S6. When the gas concentration exceeds the threshold, a leak is determined to have occurred at the test point of the semiconductor device. Specifically, the output gas concentration is compared with the preset threshold. If the concentration value exceeds the preset alarm threshold, the system will activate an alarm, determining that a leak has occurred at the test point of the semiconductor device.

[0045] In some embodiments, controlling the laser emitter 270 to emit a laser so that the laser passes through the conversion cavity 210 and then illuminates the laser detector 500 includes controlling the laser emitter 270 to emit a laser so that a portion of the laser passes through one of the optical fibers and enters the conversion cavity 210 and illuminates the laser detector 500; the remaining portion of the laser passes through another optical fiber and enters the reference gas chamber 250 and illuminates the reference detector 260.

[0046] In some embodiments, converting the electrical signal into a gas concentration includes calibrating the electrical signal based on the characteristic absorption peak amplitude of the characteristic gas obtained by the reference detector 260; and converting the calibrated electrical signal amplitude into a gas concentration. Specifically, the reference detector 260 is located at the output end of the reference gas chamber 250 and is used to receive the transmitted light intensity of the laser light passing through the characteristic gas of known concentration within the reference gas chamber 250. Since the gas concentration within the reference gas chamber 250 is fixed and the amplitude of its characteristic absorption peak is also known, the transmitted light intensity measured by the reference detector 260 can directly reflect the current power of the laser and the state of the optical system. During the calibration process, two-point calibration is performed using a characteristic gas of known concentration, i.e., measuring the transmitted light intensity and corresponding electrical signal amplitude at low and high concentrations of the characteristic gas, respectively. The low-concentration characteristic gas is typically selected near the lower limit of the detection range; for example, if the detection range is 0-100 ppb, the low-concentration characteristic gas might be selected at around 10 ppb. High-concentration characteristic gases are typically selected near the upper limit of the detection range. For example, if the detection range is 0-100 ppb, the high-concentration characteristic gas might be around 90 ppb. No specific restrictions are imposed here; in actual detection, different values ​​are selected depending on the characteristic gas; or a uniform low concentration of 10 ppb and a high concentration of 90 ppb can be used. Let the concentration of the low-concentration characteristic gas be C1, and the concentration of the high-concentration characteristic gas be C2. When the reference gas chamber 250 is filled with the low-concentration characteristic gas, the electrical signal detected by the reference detector 260 is R1; when the reference gas chamber 250 is filled with the high-concentration characteristic gas, the electrical signal detected by the reference detector 260 is R2. The calibration coefficient k is then k = (C2 - C1) / (R2 - R1). In the process of converting the electrical signal into gas concentration, the digital signal processor generates a reference signal, which is a high-frequency sine wave, used to modulate the drive current of the laser emitter 270 to modulate the laser wavelength. The digitized photoacoustic signal is multiplied by the reference signal and its 90-degree phase-shifted signal (quadrature signal), respectively, to generate two outputs: an in-phase component (X) and a quadrature component (Y). Next, the X and Y components pass through a low-pass filter to remove high-frequency noise, yielding a DC signal. The filter parameters can be dynamically adjusted according to signal quality, thus achieving an optimal balance between response speed and noise suppression. According to the formula... The signal amplitude R is calculated and compensated in real time. This amplitude is directly related to the gas concentration. The compensated signal amplitude R is then converted into a gas concentration, defined as C, using the formula C = k × R, thus obtaining the concentration of the corresponding characteristic gas.

[0047] The implementation principle of the detachable leak detection device and method for semiconductor equipment in this application is as follows: Based on photoacoustic spectroscopy technology, a characteristic gas is excited by laser to generate a photoacoustic signal, which is captured and converted into an electrical signal by a conversion device 280. After digital phase-locked amplification and compensation processing, it is converted into a gas concentration value, which is compared with a preset threshold to determine whether a leak has occurred at the test point of the semiconductor equipment. The device adopts a modular design, with the main frame 100 detachably installed on the semiconductor equipment to adapt to the detection requirements of different characteristic gases. It can achieve high-sensitivity detection, while modularity facilitates maintenance and replacement. Furthermore, laser wavelength locking and calibration are achieved through a reference gas chamber 250, ensuring long-term stability and measurement accuracy. It is suitable for leak monitoring of various toxic and harmful gases in semiconductor processes, thereby ensuring production safety and environmental quality.

[0048] While embodiments of the present invention have been described in detail above, it will be apparent to those skilled in the art that various modifications and variations can be made to these embodiments. However, it should be understood that such modifications and variations fall within the scope and spirit of the invention as set forth in the claims. Furthermore, the invention described herein may have other embodiments and can be implemented or carried out in various ways.

Claims

1. A detachable leakage detection device for semiconductor equipment, characterized in that, include: A mainframe, detachably mounted on the semiconductor device; A conversion module is provided on the main frame; the conversion module includes a conversion cavity, and the side wall of the conversion cavity is provided with an air inlet pipe and an exhaust pipe. The air inlet pipe is used to communicate with the test point so that the characteristic gas in the test point enters the conversion cavity through the air inlet pipe and is discharged through the exhaust pipe. A laser emitter is mounted on the main frame and positioned on one side of the conversion cavity. It is used to emit a laser into the conversion cavity so that the laser enters the conversion cavity and is absorbed by the characteristic gas to generate a photoacoustic signal. A conversion device, disposed on the side wall of the conversion cavity, is used to receive the photoacoustic signal and convert the photoacoustic signal into an electrical signal; A filter module is provided in the intake pipe to filter the characteristic gas entering the conversion chamber through the intake pipe; An air extraction module is installed in the exhaust pipe to control the opening and closing of the exhaust pipe.

2. The detachable leak detection device according to claim 1, characterized in that, Both ends of the conversion cavity are provided with light-transmitting elements, which are transparent, so that the laser enters the conversion cavity after passing through the light-transmitting elements.

3. The detachable leak detection device according to claim 2, characterized in that, The diameter of the end of the conversion cavity is larger than the diameter of the middle part of the conversion cavity so that both ends of the conversion cavity form anechoic cavities; the light-transmitting element is disposed in the anechoic cavity and covers the end of the conversion cavity; a laser detector is provided at the end of the conversion cavity to receive the laser light passing through the conversion cavity.

4. The detachable leak detection device according to claim 1, characterized in that, It also includes a collimating lens, which is disposed between the anechoic cavity and the laser emitter, so that the laser enters the conversion cavity after passing through the collimating lens and the anechoic cavity.

5. The detachable leak detection device according to claim 1, characterized in that, The conversion module further includes a reference gas chamber and a reference detector; the reference gas chamber is filled with a reference gas; the laser emitted by the laser emitter passes through the reference gas chamber and is received by the reference detector to form a reference signal.

6. The detachable leak detection device according to claim 1, characterized in that, The conversion cavity is cylindrical, and its volume is less than or equal to 5 cm³.

7. The detachable leak detection device according to claim 1, characterized in that, The filtration module includes a heated filtration device and a particulate filtration device. The heated filtration device is located between the particulate filtration device and the conversion chamber, so that the gas passes through the particulate filtration device and the heated filtration device in sequence before entering the conversion chamber.

8. A leakage detection method for a semiconductor device, characterized in that, Applied to the detachable leak detection device according to any one of claims 1-7, the leak detection method includes the following steps. The characteristic gas at the test point in the semiconductor device is introduced into the conversion chamber through the inlet pipe; The laser emitter is controlled to emit a laser, which then shines on the laser detector after passing through the conversion cavity; the characteristic gas in the conversion cavity absorbs the laser and vibrates, generating a photoacoustic signal. The photoacoustic signal is collected using a conversion device and converted into an electrical signal; The electrical signal is converted into gas concentration. Set a threshold; When the gas concentration is greater than the threshold, it is determined that a leak has occurred at the test point of the semiconductor device.

9. The leakage detection method according to claim 8, characterized in that, The step of controlling the laser emitter to emit laser light, so that the laser light passes through the conversion cavity and then illuminates the laser detector, includes: The laser emitter is controlled to emit laser light, so that a portion of the laser light enters the conversion cavity through one of the optical fibers and irradiates the laser detector; the remaining portion of the laser light enters the reference gas chamber through the other optical fiber and irradiates the reference detector.

10. The leakage detection method according to claim 9, characterized in that, The process of converting the electrical signal into gas concentration includes, The electrical signal is calibrated based on the amplitude of the characteristic absorption peak of the characteristic gas obtained from the reference detector. The calibrated electrical signal amplitude is converted into the gas concentration.

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