Non-dispersive infrared gas detection system, method, electronic device, and storage medium

Abstract

The application discloses a kind of non-dispersion infrared gas detection system, method, electronic equipment and storage medium, it is related to semiconductor detection technical field, the system includes: infrared light source module generates detection infrared light;Electro-optic polarization modulator according to preset frequency switching detection infrared light polarization state;Semiconductor circular dichroism absorption layer absorbs detection infrared light and generates non-uniform heat distribution;First conversion layer converts non-uniform heat distribution into spin current;Second conversion layer converts spin current into lateral voltage signal;Signal processing module extracts polarization response signal in lateral voltage signal according to preset frequency, determines the total light intensity attenuation of detection infrared light, determines absorption signal according to total light intensity attenuation, determines the target concentration of at least one gas component in the gas to be detected according to absorption signal and polarization response signal.The application realizes the in-situ on-line continuous detection of the concentration of multiple gases in the gas conveying process of MOCVD equipment, and supports predictive maintenance of gas circuit.

Description

Technical Field

[0001] This invention relates to the field of semiconductor detection technology, and more specifically to nondispersive infrared gas detection systems, methods, electronic devices, and storage media. Background Technology

[0002] In MOCVD (Metal-Organic Chemical Vapor Deposition) processes, the precursor is vaporized by a bubbler and then transported to the reaction chamber by a carrier gas. Since the precursor is a gas, its concentration stability is affected by multiple factors. To optimize the process, real-time monitoring of the precursor concentration is necessary, and parameters such as gas flow rate, temperature, and pressure should be adjusted based on feedback to form a closed-loop control. Currently, non-dispersive infrared (NDIR) gas analysis technology is used to detect MOCVD precursor concentration. NDIR gas detection technology can selectively detect various types of gases based on the fingerprint absorption characteristics of gas molecules on specific infrared spectra. However, due to the wide variety of precursors, cross-talk problems exist within the limited bandwidth.

[0003] Currently, there are various detection solutions to address the cross-interference problem, such as multi-channel hardware solutions, algorithm compensation solutions, and reference channel compensation solutions. However, the detectors in these solutions measure light intensity attenuation in a single dimension. When multiple precursors are present, the system still faces the underdetermined problem of "one equation, multiple unknowns." The insufficient measurement dimension leads to cross-interference from multiple gases, making it difficult to distinguish between different gases. Furthermore, when multiple gases are mixed, it is difficult to measure the concentration of different gases separately.

[0004] Therefore, existing technologies have the problem that when measuring the concentration of a mixture of multiple gases using non-dispersive infrared gas detection technology, only the light intensity dimension data is measured. The cross-interference of multiple gases makes it difficult to measure the concentration of different gases separately. Summary of the Invention

[0005] This invention provides a nondispersive infrared gas detection system, method, electronic device, and storage medium to solve the problem that when measuring the concentration of a mixture of multiple gases using nondispersive infrared gas detection technology, only light intensity data is measured, and the cross-interference of multiple gases makes it difficult to measure the concentration of different gases separately.

[0006] In a first aspect, the present invention provides a nondispersive infrared gas detection system, installed beside the inlet gas path of an MOCVD equipment, the system comprising: An optical gas cell is used to pass through a gas to be detected, wherein the gas to be detected contains multiple gas components; The infrared light source module is used to generate detection infrared light of the target wavelength and to project the detection infrared light into the optical gas chamber; An electro-optic polarization modulator is disposed between the infrared light source module and the optical gas cell. The electro-optic polarization modulator is used to switch the polarization state of the detected infrared light between a first preset polarization state and a second preset polarization state according to a preset frequency. A semiconductor circular dichroic absorption layer is disposed after the exit window of the optical gas cell to absorb and detect infrared light and generate a non-uniform heat distribution based on the detected infrared light. The first conversion layer is disposed below the semiconductor circular dichroic absorption layer and is used to convert non-uniform thermal distribution into spin current. The second conversion layer is disposed below the first conversion layer and is used to convert spin current into a transverse voltage signal according to the transverse electrode pair, wherein the transverse electrode is contained in the second conversion layer; The signal processing module is connected to the transverse electrode pair and is used to extract the polarization response signal from the transverse voltage signal according to the preset frequency, determine the total light intensity attenuation of the detected infrared light using the light intensity detection channel, and determine the absorption signal based on the total light intensity attenuation. The signal processing module is also used to determine the target concentration of at least one gaseous component in the gas to be detected based on the absorption signal and the polarization response signal.

[0007] In one alternative implementation, the system further includes: a controller; The controller is connected to the concentration output terminal of the signal processing module, the mass flow controller of the MOCVD equipment, and the bubbler temperature controller of the MOCVD equipment to determine the concentration deviation between the target concentration and the corresponding preset concentration setpoint. The controller is also used to output a flow rate regulation signal to the mass flow controller and a temperature regulation signal to the bubbler temperature controller based on the concentration deviation.

[0008] This system achieves active closed-loop concentration control, simultaneously adjusting carrier gas flow and bubbler temperature based on deviations to rapidly suppress concentration fluctuations at the source. Compared to existing non-dispersive infrared gas detection technologies, which only passively measure and require upper-level computer intervention, this system deeply integrates detection and control, transforming post-event alarms into real-time adjustments, significantly enhancing the stability and anti-interference capabilities of epitaxial processes.

[0009] In one optional implementation, the signal processing module includes: a precursor delivery status detection unit; The precursor delivery status detection unit is connected to the concentration output terminal of the signal processing module to acquire the concentration signal corresponding to the target concentration, perform statistical processing on the concentration signal, and obtain the standard deviation and drift trend characteristics of the concentration signal within a preset time window. The precursor delivery status detection unit is also used to compare the standard deviation with the preset control upper limit, obtain the comparison result, and determine whether the target concentration is under statistical control based on the comparison result and the sign of the drift trend characteristics. The precursor delivery status detection unit is also used to output a process abnormality warning signal when it is determined that the target concentration is not in a statistically controlled state.

[0010] This system enables real-time statistical monitoring of concentration stability. Using both standard deviation and drift trend criteria, it automatically identifies abnormal trends such as slow drift and provides timely warnings. Compared to existing non-dispersive infrared gas detection technologies that rely solely on fixed threshold alarms and cannot capture early degradation trends, this system represents an upgrade from alarms for exceeding limits to trend prediction, supporting predictive maintenance and preventing process failures.

[0011] In one optional implementation, the signal processing module further includes: a precursor source container inventory tracking unit; The precursor source container inventory tracking unit is connected to the concentration output terminal of the signal processing module and the carrier gas flow monitoring terminal of the MOCVD equipment. It is used to acquire the concentration signal corresponding to the concentration output terminal and the carrier gas flow monitoring terminal, and to perform time integration on the concentration signal and the carrier gas flow signal to obtain the cumulative molar amount of gas component consumed corresponding to the target concentration. The precursor source container inventory tracking unit is also used to calculate the remaining usable proportion of the precursor source container based on the ratio of the cumulative consumed moles to the preset loaded moles of the precursor source container. The precursor source container inventory tracking unit is also used to output a replacement scheduling signal for the precursor source container when the remaining available proportion is less than a preset replacement threshold.

[0012] This system enables real-time quantitative tracking of precursor reserves. By integrating concentration and carrier gas flow rate, it accurately calculates the cumulative molar consumption and remaining percentage, and proactively issues warnings when reserves are insufficient. Compared to existing systems that rely on manual recording or experience-based judgment, this system achieves digital and automated management of source container inventory, preventing production interruptions or wafer scrapping due to precursor depletion.

[0013] In one optional embodiment, the semiconductor circular dichroic absorption layer exhibits a circular dichroic response in the characteristic absorption spectral region of the gas to be detected, and the anisotropy factor of the circular dichroic response is 10. - ³ to 10 - ²; The first conversion layer is made of a magnetic insulating material and is used to convert non-uniform heat distribution into spin current through the spin Seebeck effect.

[0014] In one alternative implementation, the second conversion layer is made of a material with a spin Hall effect, used to convert spin current into a transverse voltage signal via the inverse spin Hall effect; The preset frequency is 100kHz to 1MHz, and the preset frequency is greater than the frequency of temperature fluctuation in the bubbler of the MOCVD equipment. The polarization extinction ratio of the electro-optic polarization modulator is greater than 30 dB; The optical path length of the optical cell is 10 to 30 meters.

[0015] In one alternative embodiment, the optical chamber includes a back pressure regulator and a heating jacket; Back pressure regulator is used to control the pressure of the optical cell within a preset pressure range; The heating jacket is used to control the temperature of the optical chamber within a preset temperature range.

[0016] In one optional implementation, the signal processing module is further configured to establish an absorption signal equation based on the absorption signal and a polarization response signal equation based on the polarization response signal. The absorption signal equation satisfies: ,in, This represents the total absorption value. This represents the absorption coefficient of target gas component i. This indicates the concentration of target gas component i. Indicates optical path length; The polarization response signal equation satisfies: ,in, This represents the total polarization response value. The polarization response coefficient represents the target gas component i; The signal processing module is also used to solve the absorption signal equation and the polarization response signal equation simultaneously to determine the target concentration of at least one gaseous component in the gas to be detected.

[0017] This system achieves the physical fusion of light intensity and polarization information, accurately solving for the concentration of each component by simultaneously solving two independent equations, thus addressing the cross-interference caused by spectral overlap at its mathematical root. Compared to existing compensation schemes that rely on algorithmic calculations, this system achieves a breakthrough in two-dimensional decoupling, ensuring the determinism and high accuracy of the measurement results.

[0018] In one optional implementation, the signal processing module further includes an in-situ calibration unit; The in-situ calibration unit is connected to the optical gas chamber and the standard gas source; The in-situ calibration unit is used to switch the input line of the optical gas cell from being connected to the output line of the bubbler of the MOCVD equipment to being connected to the standard gas source during the non-process period of the MOCVD equipment. The in-situ calibration unit is also used to introduce standard gas of known concentration into the optical gas cell using a standard gas source to obtain the measured absorption signal and the measured polarization response signal of the standard gas. The in-situ calibration unit is also used to update the absorption coefficient in the absorption signal equation based on the measured absorption signal. The polarization response coefficients in the polarization response signal equation are updated based on the measured polarization response signal. .

[0019] This system uses an in-situ calibration unit to update the absorption signal equation. and polarization response signal equation This ensures the measurement accuracy of the system during long-term operation. Calibration can be completed without disassembling the equipment, solving the problem that traditional nondispersive infrared gas detection technology relies on periodic manual calibration and cannot be updated online, thus improving the system's automation level and reliability.

[0020] In one optional embodiment, the output pipeline of the optical gas cell is equipped with a normally closed pneumatic shut-off valve; the signal processing module further includes a concentration limit exceeding determination unit, which is connected to the concentration output terminal of the signal processing module and the normally closed pneumatic shut-off valve respectively. The concentration limit determination unit is used to obtain the real-time concentration of the first target gas component and compare the real-time concentration with the preset upper limit value and the preset lower limit value respectively. The concentration limit determination unit is also used to output a cut-off trigger signal to the normally closed pneumatic shut-off valve when the real-time concentration exceeds the preset upper limit or the real-time concentration is lower than the preset lower limit.

[0021] This system enables autonomous detection and rapid shut-off when concentration exceeds limits. Upon exceeding the limit, it directly triggers a normally closed pneumatic shut-off valve, eliminating the need for an intermediate host computer. Compared to existing non-dispersive infrared gas detection technologies that only output concentration signals requiring external judgment, this system reduces the safety response time from seconds to milliseconds, upgrading from passive alarm to proactive security, effectively ensuring the safe use of highly toxic precursors.

[0022] In one optional implementation, the signal processing module further includes a safety interlock unit; the safety interlock unit is connected to the output terminal of the concentration exceeding the limit determination unit; The safety interlock unit is used to output a process pause command to the process control system of the MOCVD equipment, a carrier gas switching command to the carrier gas supply system of the MOCVD equipment, and an emergency discharge command to the exhaust system of the MOCVD equipment when a cut-off trigger signal is received. The carrier gas switching command is used to switch the carrier gas to inert purge gas.

[0023] This system enables multi-channel parallel safety linkage upon concentration exceeding limits, simultaneously executing process suspension, carrier gas switching to inert purging, and emergency discharge, without requiring manual intervention or host computer intervention. Compared to existing non-dispersive infrared gas detection technologies that only measure concentration and rely on external systems for judgment and handling, which are characterized by lag and single-point limitations, this system improves the response speed and system safety in precursor accidents.

[0024] In one alternative implementation, the wavelength of the detected infrared light includes the overlapping region of the characteristic absorption spectra of the second target gas component and the third target gas component in the gas to be detected.

[0025] In one alternative embodiment, the gas to be detected is at least two organometallic compounds or hydride precursors that have structural asymmetry and whose corresponding infrared absorption spectra overlap.

[0026] In a second aspect, the present invention provides a nondispersive infrared gas detection method, which is applied to a nondispersive infrared gas detection system according to the first aspect or any corresponding embodiment thereof, the method comprising: The system generates detection infrared light of the target wavelength and directs it into an optical gas cell, which is used to allow the gas to be detected to pass through. The gas to be detected contains multiple gas components. The detection of infrared light polarization state is switched between a first preset polarization state and a second preset polarization state according to a preset frequency; It absorbs and detects infrared light, and generates a non-uniform heat distribution based on the detected infrared light. Converting non-uniform thermal distribution into spin current; Convert spin current into a transverse voltage signal; The polarization response signal is extracted from the transverse voltage signal according to the preset frequency. The total light intensity attenuation of the detected infrared light is determined by the light intensity detection channel. The absorption signal is determined based on the total light intensity attenuation. The target concentration of at least one gaseous component in the gas to be detected is determined based on the absorption signal and the polarization response signal.

[0027] Thirdly, the present invention provides an electronic device, comprising: a memory and a processor, wherein the memory and the processor are communicatively connected to each other, the memory stores computer instructions, and the processor executes the computer instructions to perform the nondispersive infrared gas detection method of the second aspect or any corresponding embodiment described above.

[0028] Fourthly, the present invention provides a computer-readable storage medium storing computer instructions for causing a computer to perform the nondispersive infrared gas detection method described in the second aspect or any corresponding embodiment thereof.

[0029] In this invention, an optical gas chamber receives the gas to be detected, and an infrared light source module generates detection infrared light of a preset wavelength, which is then incident into the optical gas chamber. An electro-optic polarization modulator switches the polarization state of the detection infrared light between a first and a second preset polarization state according to a preset frequency. A semiconductor circular dichroism absorption layer absorbs the detection infrared light, generating a non-uniform thermal distribution. A first conversion layer converts the non-uniform thermal distribution into a spin current, and a second conversion layer converts the spin current into a transverse voltage signal. A signal processing module extracts a polarization response signal from the transverse voltage signal according to a preset frequency. Simultaneously, a light intensity detection channel determines the total light intensity attenuation of the detection infrared light, determines the absorption signal based on the total light intensity attenuation, and determines the target concentration of at least one gas component in the gas to be detected based on the absorption signal and the polarization response signal. This system introduces polarization response as a new measurement dimension, extending the one-dimensional light intensity measurement of traditional non-dispersive infrared gas detection systems to a two-dimensional synchronous measurement of light intensity and polarization response. This transforms the solution for multiple precursor concentrations from underdetermined to well-determined, eliminating cross-interference caused by spectral overlap. Furthermore, the polarization response signal originates from the relative difference between left-handed and right-handed circularly polarized light, rather than the absolute value of light intensity. Factors such as light source aging and window contamination do not affect the extraction of the polarization response signal. By employing two-dimensional synchronous measurement of light intensity and polarization response, cross-interference between multiple gases can be avoided, allowing for the separate measurement of different gas concentrations. Multiple gas concentrations are output simultaneously in a single measurement, eliminating the need for filter switching and resulting in a short switching response time. The detection process involves conversion pathways involving light, heat, spin, and electricity. Utilizing a three-stage coupling of circular dichroism absorption, the spin Seebeck effect, and the inverse spin Hall effect, traditional light intensity detection is extended to spin signal detection. This invention directly connects the optical gas chamber to the gas output pipeline at the front end of the equipment, enabling in-situ online continuous detection. The precursor delivery status detection unit and the precursor source container inventory tracking unit provide statistical process control and consumption prediction, supporting predictive maintenance of the gas path in semiconductor MOCVD equipment. Attached Figure Description

[0030] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the structure of a nondispersive infrared gas detection system according to an embodiment of the present invention; Figure 2 This is an example diagram illustrating the application scenario structure of an online precursor concentration detection system for MOCVD equipment according to an embodiment of the present invention; Figure 3This is a schematic diagram of a longitudinal cross-section of a stacked structure detector according to an embodiment of the present invention; Figure 4 This is a schematic diagram of the concentration-absorption signal curve and the concentration-polarization response signal curve according to an embodiment of the present invention; Figure 5 This is a schematic diagram of the concentration-time curve according to an embodiment of the present invention; Figure 6 This is a schematic flowchart of a nondispersive infrared gas detection method according to an embodiment of the present invention; Figure 7 This is a schematic diagram of the hardware structure of an electronic device according to an embodiment of the present invention. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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.

[0033] It is understood that before using the technical solutions disclosed in the various embodiments of the present invention, users should be informed of the types, scope of use, and usage scenarios of the personal information involved in the present invention and their authorization should be obtained in accordance with relevant laws and regulations through appropriate means.

[0034] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0035] According to an embodiment of the present invention, a non-dispersive infrared gas detection system is provided, which is installed beside the inlet gas path of an MOCVD equipment. Figure 1 This is a schematic diagram of the structure of a nondispersive infrared gas detection system according to an embodiment of the present invention, as shown below. Figure 1 As shown, the system includes: An optical gas cell is used to pass through a gas to be detected, wherein the gas to be detected contains multiple gas components; The infrared light source module is used to generate detection infrared light of the target wavelength and to project the detection infrared light into the optical gas chamber; An electro-optic polarization modulator is positioned between the infrared light source module and the optical gas cell. The electro-optic polarization modulator is used to switch the polarization state of the detected infrared light between a first preset polarization state and a second preset polarization state according to a preset frequency. A semiconductor circular dichroic absorption layer is disposed after the exit window of the optical gas cell to absorb and detect infrared light and generate a non-uniform heat distribution based on the detected infrared light. The first conversion layer is disposed below the semiconductor circular dichroic absorption layer and is used to convert non-uniform thermal distribution into spin current. The second conversion layer is disposed below the first conversion layer and is used to convert spin current into a transverse voltage signal according to the transverse electrode pair, wherein the transverse electrode is contained in the second conversion layer; The signal processing module is connected to the transverse electrode pair and is used to extract the polarization response signal from the transverse voltage signal according to the preset frequency, determine the total light intensity attenuation of the detected infrared light using the light intensity detection channel, and determine the absorption signal based on the total light intensity attenuation. The signal processing module is also used to determine the target concentration of at least one gaseous component in the gas to be detected based on the absorption signal and the polarization response signal.

[0036] Specifically, the nondispersive infrared gas detection system is used for online detection during gas transport. The infrared light source module includes a wavelength-tunable quantum cascade laser, which generates detection infrared light at a preset wavelength. The target wavelength is, for example, a wavelength within the characteristic absorption spectral region of the precursor gas being tested, such as the ν1 / ν3 vibrational band (1960–2260 cm⁻¹) of arsine (AsH₃). - ¹) The ν1 / ν3 vibrational band with phosphine (PH3) (2264–2288 cm) - The overlapping area of ​​¹). The infrared light source module will detect infrared light entering the optical gas cell.

[0037] An optical gas chamber is positioned after the infrared light source module and the electro-optic polarization modulator. The optical gas chamber has a gas inlet and a gas outlet. The gas inlet is connected to the output pipe of the bubbler in the MOCVD equipment. The optical gas chamber stores the gas to be detected input from the bubbler. The gas to be detected contains multiple gas components, for example: the gas to be detected consists of at least two organometallic compounds or hydride precursors with structural asymmetry and overlapping infrared absorption spectra; the at least two organometallic compounds or hydride precursors are selected from at least two of the following: Group V hydride precursors, selected from at least one of arsine, phosphine, ammonia (NH3), and antimonyane (SbH3); Group III organometallic compound precursors, selected from at least one of trimethylgallium (TMGa), trimethylaluminum (TMAl), trimethylindium (TMIn), triethylgallium (TEGa), and diethylzinc (DEZn). Figure 2As shown, the non-dispersive infrared gas detection system is installed beside the inlet gas path of the MOCVD equipment. The optical gas chamber in this system is connected to the MOCVD equipment, which includes a reaction chamber. The optical gas chamber has a gas inlet and a gas outlet. The gas inlet is connected to the bubbler output pipeline of the MOCVD equipment and is connected to two bubblers. One bubbler is used to vaporize arsine and deliver it to the optical gas chamber, and the other bubbler is used to vaporize phosphine and deliver it to the optical gas chamber. The carrier gas for both bubblers is hydrogen, and the temperature of both is 25°C.

[0038] The first preset polarization state is, for example, LCP (Left-Handed Circular Polarization). The second preset polarization state is, for example, RCP (Right-Handed Circular Polarization). The preset frequency is, for example, frequency f0, with a value ranging from 100kHz to 1MHz. An electro-optic polarization modulator is positioned between the infrared light source module and the optical gas cell. The electro-optic polarization modulator switches between the first and second preset polarization states to detect the polarization state of infrared light according to the aforementioned preset frequency. The electro-optic polarization modulator causes LCP and RCP to alternately pass through the optical gas cell, interacting with the arsine and phosphine mixture therein. Due to differences in molecular structural asymmetry, arsine and phosphine exhibit different degrees of selective absorption of LCP / RCP (circular dichroism difference). Furthermore, the electro-optic polarization modulator has wide applicability in the mid-infrared range of 2.6μm to 16μm, allowing the system to flexibly and rapidly switch between different gas detections by adjusting the locked wavelength of the quantum cascade laser. Its polarization extinction ratio is greater than 30dB, which is the ratio of the light intensity of the main polarization state to that of the orthogonal polarization state. This ensures that the polarization crosstalk during the switching process of LCP and RCP is small enough to avoid interference with the circular dichroism measurement signal and to guarantee the quality of the polarization response signal.

[0039] A semiconductor circular dichroic absorption layer is disposed downstream of the optical path of the optical cell. It is made of a semiconductor material with circular dichroic effect. The semiconductor circular dichroic absorption layer is configured to absorb the detection infrared light in the left-hand circular polarization state and the right-hand circular polarization state differently, and to convert the difference between the absorbed detection infrared light in the left-hand circular polarization state and the right-hand circular polarization state into a non-uniform thermal distribution.

[0040] The semiconductor circular dichroism (CDD) absorber layer is located behind the exit window of the optical gas cell and on top of the stacked detector chip. It is the first functional layer that infrared light encounters after exiting the optical gas cell and serves as the incident surface of the detector chip. Spatially, the CDD absorber layer is directly behind the exit window of the optical gas cell. After the infrared light passes through the optical gas cell and is absorbed by the gas, it exits through the exit window and directly enters the CDD absorber layer. Between the CDD absorber layer and the exit window of the optical gas cell lies the detector chip's encapsulation window. This window, which can be made of materials such as BaF2 or ZnSe, serves as an isolation and support mechanism. Infrared light penetrates the encapsulation window before reaching the CDD absorber layer. The encapsulation window is part of the detector chip and is located before the CDD absorber layer and after the exit window of the optical gas cell. From the perspective of the stacked detector structure, the CDD absorber layer is located at the very top of all functional layers. Below it are, in order, a thermal isolation layer, a spin-thermal conversion layer, and a spin-charge conversion layer, with the substrate at the very bottom. Light is first absorbed and converted into heat in the semiconductor circular dichroism absorption layer, and then the heat is transferred downwards to the spin-thermal conversion layer. Finally, an electrical signal is output in the spin-charge conversion layer. The semiconductor circular dichroism absorption layer is the starting point of the entire signal conversion path.

[0041] In a semiconductor circular dichroism absorption layer, such as a chiral hybrid perovskite, when detection infrared light passing through an optical cell is incident on the layer, the LCP and RCP are absorbed to different degrees due to the circular dichroism effect of the chiral hybrid perovskite, resulting in different carrier excitations and Joule thermal distributions. The magnitude of this non-uniform thermal distribution is related to the difference in circular dichroism between arsine and phosphine. Carrier excitation is an intermediate process; after absorption, LCP and RCP excite different numbers of electron-hole pairs. Joule thermal distribution is the final result; carriers transfer energy to the lattice through relaxation, generating heat. The non-uniform thermal distribution is the difference between carrier excitation and Joule thermal distribution; the Joule thermal distributions generated by LCP and RCP differ spatially, and this difference is the non-uniform thermal distribution.

[0042] The first conversion layer, for example, is a spin-thermal conversion layer disposed beneath a semiconductor circular dichroism absorption layer. This first conversion layer is configured to convert non-uniform heat distribution into spin current. For example, the non-uniform heat distribution is transferred to the spin-thermal conversion layer through an alumina (Al₂O₃) thermal isolation layer. The spin Seebeck effect in the spin-thermal conversion layer converts the thermal gradient into a directional spin current. The thermal gradient is the rate of change of heat distribution in space, i.e., the rate of change of temperature with respect to distance; heat distribution refers to the spatial distribution of temperature; the thermal gradient is the spatial derivative of the heat distribution, reflecting the magnitude of the driving force for heat flow in a certain direction. A thermal gradient exists only when there is a non-uniform heat distribution (different temperatures in space) (heat flows from high-temperature areas to low-temperature areas); if the heat distribution is uniform (i.e., the temperature is the same everywhere), the thermal gradient is zero.

[0043] The second conversion layer, for example, is a spin-charge conversion layer (Pt / β-W), disposed below the first conversion layer. This second conversion layer has a pair of lateral electrodes and is configured to convert the spin current into a lateral voltage signal. The inverse spin Hall effect in the second conversion layer converts the spin current into a lateral voltage signal. The frequency of the lateral voltage signal is f0, and its amplitude is related to the concentration difference between arsine and phosphine.

[0044] The signal processing module is connected to the lateral electrode pair. The module includes a lock-in amplifier, which extracts the amplitude of the component with frequency f0 in the lateral voltage signal using a preset frequency as a reference frequency, and uses this amplitude as the polarization response signal. The module also includes a light intensity detection channel configured to measure the total light intensity attenuation. The total light intensity attenuation of the detected infrared light is determined using this channel, and the absorption signal A is determined based on the total light intensity attenuation. For example, the lock-in amplifier extracts the amplitude of the lateral voltage signal using f0 as a reference frequency, and uses this amplitude as the polarization response signal P. High-frequency modulation keeps the signal away from the 50 / 60Hz power frequency interference and low-frequency mechanical vibration noise of the MOCVD equipment, improving the signal-to-noise ratio by >60dB.

[0045] The signal processing module establishes an absorption signal equation based on the absorption signal and a polarization response signal equation based on the polarization response signal. By simultaneously solving the absorption signal equation and the polarization response signal equation, the module calculates the target concentration C of at least one gaseous component in the gas to be detected. i The real-time concentration of each precursor is output synchronously.

[0046] The nondispersive infrared gas detection system provided in this embodiment utilizes an optical gas chamber through which the gas to be detected passes; an infrared light source module generates detection infrared light of a preset wavelength and directs it into the optical gas chamber; an electro-optic polarization modulator switches the polarization state of the detection infrared light between a first preset polarization state and a second preset polarization state according to a preset frequency; a semiconductor circular dichroism absorption layer absorbs the detection infrared light to generate a non-uniform thermal distribution; a first conversion layer converts the non-uniform thermal distribution into a spin current; a second conversion layer converts the spin current into a transverse voltage signal; a signal processing module extracts a polarization response signal from the transverse voltage signal according to a preset frequency; a light intensity detection channel determines the total light intensity attenuation of the detection infrared light; the absorption signal is determined based on the total light intensity attenuation; and the target concentration of at least one gas component in the gas to be detected is determined based on the absorption signal and the polarization response signal. This system introduces polarization response as a new measurement dimension, extending the one-dimensional light intensity measurement of traditional nondispersive infrared gas detection technology to a two-dimensional synchronous measurement of light intensity and polarization response. This transforms the solution for multiple precursor concentrations from underdetermined to well-determined and eliminates cross-interference. Furthermore, this system does not rely on absolute light intensity, eliminating system drift: the polarization response signal originates from the relative difference between LCP and RCP, rather than the absolute value of light intensity. Factors such as light source aging and window contamination only affect the total light intensity and do not affect the extraction of the polarization response signal, thus eliminating the system's zero-drift problem. When measuring the concentration of a mixture of multiple gases using non-dispersive infrared gas detection technology, this system performs two-dimensional synchronous measurement of light intensity and polarization response, avoiding cross-interference among multiple gases and allowing for separate measurement of the concentrations of different gases.

[0047] In some alternative implementations, the system further includes: a controller; The controller is connected to the concentration output terminal of the signal processing module, the mass flow controller of the MOCVD equipment, and the bubbler temperature controller of the MOCVD equipment to determine the concentration deviation between the target concentration and the corresponding preset concentration setpoint. The controller is also used to output a flow rate regulation signal to the mass flow controller and a temperature regulation signal to the bubbler temperature controller based on the concentration deviation.

[0048] Specifically, the controller is, for example, a PID (Proportional-Integral-Derivative) controller. The PID controller is used for closed-loop concentration control. Based on the deviation between the concentration signal and the set value, it outputs a flow regulation signal to the MFC and a temperature regulation signal to the bubbler temperature controller.

[0049] The controller is operatively coupled to the concentration output of the signal processing module, the mass flow controller of the MOCVD equipment, and the bubbler temperature controller of the MOCVD equipment. The controller receives the concentration signal of the target gas in the gas to be detected and determines the target concentration. The controller calculates the concentration deviation between the target concentration and the corresponding preset concentration setpoint, and calculates the flow regulation Δu of the MFC (Mass Flow Controller) according to the PID algorithm. MFC Bubbler temperature adjustment Δu Temp The controller adjusts the flow rate Δu accordingly. MFC Output a flow rate adjustment signal to the mass flow controller and adjust the flow rate Δu according to the bubbler temperature. Temp Output a temperature regulation signal to the bubbler temperature controller.

[0050] The process control system of the MOCVD equipment uses a PID controller to output flow regulation signals to the MFC and temperature regulation signals to the bubbler temperature controller based on the deviation between the concentration signal and the set value, forming a closed-loop control. Taking a low arsine level as an example, the closed-loop control process is as follows: the flow regulation is positive, the MFC valve opening is increased, the carrier gas flow rate is increased, and more arsine vapor is carried.

[0051] In this embodiment, active closed-loop concentration stabilization is achieved by simultaneously adjusting the carrier gas flow rate and bubbler temperature based on the deviation, thereby rapidly suppressing concentration fluctuations at the source. Compared to the limitations of existing non-dispersive infrared gas detection technologies, which only provide passive measurement and require intervention from a host computer, this embodiment deeply integrates detection and control, transforming post-event alarms into real-time adjustments, significantly enhancing the stability and anti-interference capabilities of the epitaxial process.

[0052] In some optional implementations, the signal processing module includes: a precursor delivery status detection unit; The precursor delivery status detection unit is connected to the concentration output terminal of the signal processing module to acquire the concentration signal corresponding to the target concentration, perform statistical processing on the concentration signal, and obtain the standard deviation and drift trend characteristics of the concentration signal within a preset time window. The precursor delivery status detection unit is also used to compare the standard deviation with the preset control upper limit, obtain the comparison result, and determine whether the target concentration is under statistical control based on the comparison result and the sign of the drift trend characteristics. The precursor delivery status detection unit is also used to output a process abnormality warning signal when it is determined that the target concentration is not in a statistically controlled state.

[0053] Specifically, the signal processing module also includes a precursor transport status detection unit, which is operatively coupled to the concentration output terminal of the signal processing module. The precursor transport status detection unit is used for statistical process control, performing sliding window statistics on the concentration signal, outputting the mean, standard deviation, and drift trend, and determining the statistically controlled state.

[0054] The precursor delivery status detection unit acquires the concentration signal corresponding to the target concentration, which is the target concentration of the gas component detected and calculated in the above embodiment. The precursor delivery status detection unit applies sliding window statistical processing to the concentration signal and outputs the statistical characteristics of the concentration signal within a preset time window. The statistical characteristics include the mean, standard deviation, and drift trend characteristics.

[0055] The precursor transport status detection unit compares the standard deviation with a preset control upper limit, obtains the comparison result, and determines whether the target concentration is in a statistically controlled state based on the comparison result and the sign of the drift trend characteristics. The judgment condition is, for example, that six consecutive sampling points show a monotonically increasing or decreasing trend, and that the difference between the first and last samples exceeds 2.5 ppm. The judgment process is as follows: after sampling every second, the precursor transport status detection unit reads the concentration values ​​C(t-5) to C(t) of the six most recent sampling points. The precursor transport status detection unit first checks whether these six points form a strictly increasing or strictly decreasing sequence (i.e., the difference between each pair of adjacent points maintains the same sign and is not zero). If it is not a strictly monotonically increasing sequence, the judgment criterion is not triggered. If it is a strictly monotonically increasing sequence, the difference between the first and last samples Δ = C(t) - C(t-5) is calculated, and its absolute value is compared with the threshold of 2.5 ppm. If |Δ| > 2.5 ppm, it is judged as statistically out of control, and a process abnormality warning is output, with the abnormality type being "continuous drift," and the drift direction (upward or downward) is recorded. If the difference between the first and last values ​​does not exceed 2.5 ppm, no warning will be triggered, but the count in that drift direction will still be retained for subsequent judgment.

[0056] If the precursor delivery status detection unit determines that the target concentration is not under statistical control, it will output a process abnormality warning signal.

[0057] In this embodiment, real-time statistical monitoring of concentration stability is achieved. Using both standard deviation and drift trend criteria, abnormal trends such as slow drift are automatically identified and timely warnings are issued. Compared to existing non-dispersive infrared gas detection technologies that rely solely on fixed threshold alarms and cannot capture early degradation trends, this embodiment upgrades from exceeding threshold alarms to trend prediction, supporting predictive maintenance and preventing process failures.

[0058] In some optional implementations, the signal processing module further includes: a precursor source container inventory tracking unit; The precursor source container inventory tracking unit is connected to the concentration output terminal of the signal processing module and the carrier gas flow monitoring terminal of the MOCVD equipment. It is used to acquire the concentration signal corresponding to the concentration output terminal and the carrier gas flow monitoring terminal, and to perform time integration on the concentration signal and the carrier gas flow signal to obtain the cumulative molar amount of gas component consumed corresponding to the target concentration. The precursor source container inventory tracking unit is also used to calculate the remaining usable proportion of the precursor source container based on the ratio of the cumulative consumed moles to the preset loaded moles of the precursor source container. The precursor source container inventory tracking unit is also used to output a replacement scheduling signal for the precursor source container when the remaining available proportion is less than a preset replacement threshold.

[0059] Specifically, the signal processing module also includes a precursor source container inventory tracking unit, which is operatively coupled to the concentration output terminal of the signal processing module and the carrier gas flow monitoring terminal of the MOCVD equipment.

[0060] The precursor source container inventory tracking unit acquires the concentration signal corresponding to the concentration output terminal and the carrier gas flow rate signal corresponding to the carrier gas flow rate monitoring terminal. For example, the carrier gas flow rate signal comes from the real-time MFC reading of the MOCVD equipment (e.g., 500 sccm). The role of the carrier gas: The carrier gas flows through the bubbler at a certain flow rate (unit sccm), carrying out the precursor vapor to form a mixed gas. The proportion of precursor in the mixed gas is determined by its concentration (ppm).

[0061] The precursor source container inventory tracking unit integrates the concentration signal and carrier gas flow rate signal over time to obtain the cumulative molar consumption of the gas component corresponding to the target concentration. For example, the carrier gas volumetric flow rate is converted to molar flow rate: carrier gas molar flow rate (mol / min) = F(t) / 22400; the precursor molar flow rate is calculated, with the concentration signal C(t) in ppm, i.e., per 10 6 The number of precursors in a gas mixture, precursor molar flow rate (mol / min) = carrier gas molar flow rate × precursor volume fraction = [F(t) / 22400] × [C(t) / 10] 6 Integrating over time yields the cumulative mole consumption. Concentration signal C(t) and flow rate signal F(t) are continuously collected at a fixed sampling interval Δt (e.g., 1 second). The cumulative mole consumption (mol) = Σ{[F(t)] i )×C(t i )×Δt min ] / (22400×10 6 )}, where Δt min =Δt / 60.

[0062] The precursor source container inventory tracking unit calculates the remaining usable proportion of the precursor source container based on the ratio of the cumulative consumed moles to the rated loaded moles of the precursor source container. For example, the initial loading of the bubbler is denoted as M. total (Unit: mol), the cumulative molar amount consumed is denoted as M. consumed Remaining available ratio X residual =(M total -M consumed / M total ) × 100%.

[0063] When the remaining available percentage of the precursor source container is less than a preset replacement threshold (such as 5%, 10%), the precursor source container inventory tracking unit outputs a replacement scheduling signal for the precursor source container.

[0064] In this embodiment, real-time quantitative tracking of the remaining precursor quantity is achieved. By integrating the concentration and carrier gas flow rate, the cumulative molar amount consumed and the remaining proportion are accurately calculated, and an early warning is issued when the remaining quantity is insufficient. Compared to the blind spots of existing methods that rely on manual recording or experience-based judgment, this embodiment achieves digital and automated management of the source container inventory, avoiding production interruptions or wafer scrapping due to precursor depletion.

[0065] In some optional embodiments, the semiconductor circular dichroism absorption layer exhibits a circular dichroism response in the characteristic absorption spectral region of the gas to be detected, and the anisotropy factor of the circular dichroism response is 10. - ³ to 10 - ²; The first conversion layer is made of a magnetic insulating material and is used to convert non-uniform heat distribution into spin current through the spin Seebeck effect.

[0066] Specifically, the semiconductor circular dichroism absorption layer exhibits a circular dichroism response in the characteristic absorption spectral region of the gas to be detected, and the anisotropy factor of the circular dichroism response is 10. - ³ to 10 - ². The gases to be detected include arsine and phosphine, and the anisotropy factor of the semiconductor circular dichroism absorber layer in the 4.5 μm to 4.7 μm wavelength range corresponding to arsine and phosphine is greater than 10. - ³, a clear and reliable polarization response signal can be obtained during the detection process. The semiconductor circular dichroism absorption layer is composed of at least one of the following materials: chiral hybrid perovskite, semiconductor quantum dots with circular dichroism effect, and two-dimensional semiconductor materials with circular dichroism effect.

[0067] The first conversion layer is a spin-thermal conversion layer made of a magnetic insulator material, configured to convert non-uniform heat distribution into spin current through the spin Seebeck effect. The magnetic insulator material is yttrium iron garnet (YIG), and the thickness of the spin-thermal conversion layer ranges from 100 nm to 500 nm.

[0068] In some alternative implementations, the second conversion layer is made of a material with a spin Hall effect, used to convert spin current into a transverse voltage signal via the inverse spin Hall effect; The preset frequency is 100kHz to 1MHz, and the preset frequency is greater than the frequency of temperature fluctuation in the bubbler of the MOCVD equipment. The polarization extinction ratio of the electro-optic polarization modulator is greater than 30 dB; The optical path length of the optical cell is 10 to 30 meters.

[0069] Specifically, the second conversion layer is a spin-charge conversion layer, which is made of a material with a spin Hall effect and is configured to convert spin current into a transverse voltage signal through the inverse spin Hall effect.

[0070] Materials exhibiting the spin Hall effect include, for example, platinum (Pt), β-tungsten (β-W), or topological insulators, with a spin-charge conversion layer thickness ranging from 5 nm to 15 nm.

[0071] The preset frequency of the electro-optic polarization modulator is 100 kHz to 1 MHz. Furthermore, this preset frequency is higher than the frequency of temperature fluctuations in the bubbler of the MOCVD equipment. The polarization extinction ratio of the electro-optic polarization modulator is greater than 30 dB.

[0072] The optical path length of the optical cell is 10m to 30m, and the window material of the optical cell is BaF2 or CaF2.

[0073] A semiconductor circular dichroic absorber layer, a thermal isolation layer, a spin-thermal conversion layer, a spin-charge conversion layer, and a substrate layer together constitute a stacked detector structure, such as... Figure 3 As shown, the spin-charge conversion layer contains lateral electrode pairs, which are used to output voltage signals.

[0074] In some alternative implementations, the optical chamber includes a back pressure regulator and a heating jacket; Back pressure regulator is used to control the pressure of the optical cell within a preset pressure range; The heating jacket is used to control the temperature of the optical chamber within a preset temperature range.

[0075] Specifically, the optical chamber includes a back pressure regulator and a heating jacket.

[0076] The back pressure regulator controls the pressure in the optical chamber within a preset pressure range, such as ±0.5% of the preset pressure (e.g., 1 kPa, 10 kPa, or other values ​​to meet practical needs). Minimal pressure fluctuations maintain a constant gas number density within the chamber, eliminating interference from pressure fluctuations on infrared absorption detection. The heating jacket controls the temperature in the optical chamber within a preset temperature range, such as 50–300 degrees Celsius. The temperature control accuracy of the heating jacket is ±0.1°C, eliminating the impact of temperature fluctuations on the gas absorption coefficient and molecular number density. The heating jacket effectively maintains a stable gas temperature within the optical chamber.

[0077] In some optional implementations, the signal processing module is further configured to establish an absorption signal equation based on the absorption signal and a polarization response signal equation based on the polarization response signal. The absorption signal equation satisfies: ,in, This represents the total absorption value. This represents the absorption coefficient of target gas component i at a specific wavelength. This indicates the concentration of target gas component i. Indicates optical path length; The polarization response signal equation satisfies: ,in, This represents the total polarization response value. The polarization response coefficient represents the target gas component i; The signal processing module is also used to solve the absorption signal equation and the polarization response signal equation simultaneously to determine the target concentration of at least one gaseous component in the gas to be detected.

[0078] Specifically, the target gas component i is one of the multiple gas components contained in the gas to be detected. The signal processing module establishes the absorption signal equation based on the absorption signal, for example: Equation (1). Based on the polarization response signal, the polarization response signal equation is established, for example: Equation (2).

[0079] (1) (2) in, This represents the total absorption value. This represents the absorption coefficient of target gas component i. This indicates the concentration of target gas component i. Indicates optical path length. This represents the total polarization response value. This represents the polarization response coefficient of the target gas component i. The absorption coefficient of target gas component i at a specific wavelength represents the contribution of the gas to the light intensity attenuation, and is expressed in cm⁻¹. - ¹·ppm - ¹, obtain Methods include obtaining the results through single-component calibration experiments, for example: passing a known concentration of arsine standard gas (e.g., 0, 10, 50, 100, 200 ppm) into an optical gas cell, recording the absorption signal A at each concentration, and fitting an AC curve, for example: Figure 4 The curve of arsine concentration versus absorption signal A fitted in the image is obtained, and the slope of this curve is divided by the optical path length. That is . The coefficient representing the contribution of target gas component i to the difference in circular dichroism absorption of LCP / RCP reflects the polarization-selective absorption capability caused by the asymmetry of the gas molecular structure, and is expressed in cm⁻¹. - ¹·ppm - ¹, obtain Methods include obtaining the results through single-component calibration experiments. For example, a known concentration of arsine standard gas (e.g., 0, 10, 50, 100, 200 ppm) is passed into an optical gas cell, and the polarization response signal P at each concentration is recorded. The polarization response signal P is the AC (Alternating Current) amplitude extracted by the lock-in amplifier, and a PC curve is fitted. For example: Figure 4 The curve of arsine concentration versus polarization response signal P fitted in the model is given by dividing the slope of the curve by the optical path length L. Optical path length This represents the effective path length of the infrared light interacting with the gas being tested in the optical cell, determined based on the radius of curvature of the mirrors and the number of reflections in the Herriott multipath cell. A calibration curve was plotted with concentration on the x-axis and absorption signal on the y-axis, and linear fitting was performed, yielding an absorption coefficient of 0.85 cm⁻¹ for arsine. - ¹·ppm - ¹. Similarly, by plotting the calibration curve with concentration on the x-axis and polarization response signal on the y-axis and performing linear fitting, the polarization response coefficient of arsine was found to be 0.15 cm⁻¹. - ¹·ppm - ¹. The goodness-of-fit R² of both calibration curves is greater than 0.999, confirming that the absorption signal and polarization response signal have a good linear relationship with the concentration in the concentration range of 10-200 ppm.

[0080] The signal processing module includes a concentration inversion unit, which solves the simultaneous absorption signal equation and polarization response signal equation to calculate the target concentration of at least one gaseous component in the gas to be detected. Specifically, two precursors with constant concentrations of each component are stably output from the MOCVD bubbler gas pipeline, and the mixed gas is transported to the optical chamber using hydrogen (H2) as the carrier gas. The target supply concentrations set in the process recipe are: arsine = 50 ppm and phosphine = 80 ppm. The concentrations of arsine and phosphine in the mixed gas are detected. The optical path length of the optical chamber is L = 1000 cm. The target wavelength is selected as 4.6 μm (corresponding to 2174 cm). - ¹, typical location of the overlapping region), located in the ν1 / ν3 vibrational band of arsine (1960–2260 cm). - ¹) with the ν1 / ν3 vibrational band of phosphine (2264–2288 cm) - ¹) overlapping absorption region. At 4.6 μm, the absorption coefficient of arsine is... polarization response coefficient Phosphine absorption coefficient polarization response coefficient .

[0081] The calculation process includes: Step 1, moving the known quantities to the right side of the equation, then the system of equations simplifies to... , Step 2: Solve using Cramer's rule. According to linear algebra, the solution to this system of two linear equations in two variables is: , .

[0082] For example: Under stable gas mixing conditions, the system continuously collects data at 0.2-second sampling intervals. At a specific sampling moment during the stable phase, the absorbed signal is measured. polarization response signal Divide the measured absorption signal and polarization response signal by the optical path length to obtain the absorption signal value per unit length. and polarization response signal value per unit length : ; ; Based on this, a system of two linear equations in two variables can be established: ; ; Calculate the discriminant Since D≠0, the system of equations has a unique solution.

[0083] Substitute Cramer's rule to solve: ; .

[0084] Figure 5 The curve above is the concentration-time curve of phosphine. Figure 5 The curve below shows the concentration-time curve for arsine. According to the two curves, at a certain moment during the stable phase, the concentration of arsine was 50.9 ppm and the concentration of phosphine was 82.2 ppm. The deviations from the target concentration values ​​(50 ppm for arsine and 80 ppm for phosphine) were 1.8% and 2.75%, respectively. The detection results are within ±3.0% accuracy, meeting the accuracy requirements for online monitoring of precursor concentrations in the MOCVD process. The system continuously samples and calculates at 0.2-second intervals, outputting the concentration-time curve in real time. Figure 5 As shown.

[0085] In this embodiment, the physical fusion of light intensity and polarization information is achieved. By simultaneously solving two independent equations, the concentrations of each component are accurately determined, thus resolving the cross-interference caused by spectral overlap from a mathematical perspective. Compared to existing compensation schemes that rely on algorithmic calculations, this embodiment achieves a breakthrough in two-dimensional decoupling, ensuring the determinism and high accuracy of the measurement results.

[0086] In some optional implementations, the signal processing module further includes an in-situ calibration unit; The in-situ calibration unit is connected to the optical gas chamber and the standard gas source; The in-situ calibration unit is used to switch the input line of the optical gas cell from being connected to the output line of the bubbler of the MOCVD equipment to being connected to the standard gas source during the non-process period of the MOCVD equipment. The in-situ calibration unit is also used to introduce standard gas of known concentration into the optical gas cell using a standard gas source to obtain the measured absorption signal and the measured polarization response signal of the standard gas. The in-situ calibration unit is also used to update the absorption signal equation based on the measured absorption signal. And update the polarization response signal equation based on the measured polarization response signal. .

[0087] Specifically, the signal processing module also includes an in-situ calibration unit, which is fluidly connected to the optical gas chamber and the standard gas source. The in-situ calibration unit is used to update parameters online by automatically introducing standard gas during non-process periods of the MOCVD equipment. and .

[0088] The in-situ calibration unit is configured to perform a calibration sequence during non-process periods of the MOCVD equipment. The calibration sequence includes switching the gas input of the optical chamber from the bubbler output line of the MOCVD equipment to a standard gas source, that is, switching the input line of the optical chamber from being connected to the bubbler output line of the MOCVD equipment to being connected to a standard gas source. The in-situ calibration unit uses a standard gas source to introduce standard gas of known concentrations (concentration gradients such as 0 ppm, 5 ppm, 10 ppm, 50 ppm, 100 ppm, 200 ppm, and 500 ppm) into the optical gas cell, acquiring the measured absorption signal and the measured polarization response signal of the standard gas. An example of a standard gas is phosphine standard gas.

[0089] The in-situ calibration unit updates the absorption coefficient in the absorption signal equation based on the measured absorption signal. The polarization response coefficients in the polarization response signal equation are updated based on the measured polarization response signal. .

[0090] For example, during non-process periods of the MOCVD equipment, the in-situ calibration unit automatically performs in-situ calibration, switches to a standard gas source, and introduces a standard gas of known concentration (50 ppm) for 120 seconds, recording the measured absorption signal. and polarization response signal Update the coefficient matrix elements as shown in formulas (3) and (4).

[0091] (3) (4) In this embodiment, the absorption signal equation is updated using an in-situ calibration unit. and polarization response signal equation This ensures the measurement accuracy of the system during long-term operation. Calibration can be completed without disassembling the equipment, solving the problem that traditional nondispersive infrared gas detection technology relies on periodic manual calibration and cannot be updated online, thus improving the system's automation level and reliability.

[0092] In some optional embodiments, the output line of the optical gas cell is equipped with a normally closed pneumatic shut-off valve; the signal processing module also includes a concentration limit exceeding determination unit, which is connected to the concentration output terminal of the signal processing module and the normally closed pneumatic shut-off valve respectively. The concentration limit determination unit is used to obtain the real-time concentration of the first target gas component and compare the real-time concentration with the preset upper limit value and the preset lower limit value respectively. The concentration limit determination unit is also used to output a cut-off trigger signal to the normally closed pneumatic shut-off valve when the real-time concentration exceeds the preset upper limit or the real-time concentration is lower than the preset lower limit.

[0093] Specifically, the output line of the optical gas chamber is equipped with a normally closed pneumatic shut-off valve. The signal processing module also includes a concentration limit exceeding determination unit, which is operatively coupled to the concentration output terminal of the signal processing module and the normally closed pneumatic shut-off valve.

[0094] The concentration limit judgment unit is used to obtain the real-time concentration of the first target gas component and compare it with the preset upper and lower concentration limits. For example, the process menu sets the target concentration of arsine to 50 ppm with a fluctuation range of ±3%, and the target concentration of phosphine to 30 ppm with a fluctuation range of ±2%. The preset upper concentration limit is a safety threshold, such as 48.5 ppm to 51.5 ppm for arsine and 29.4 ppm to 30.6 ppm for phosphine. The preset lower concentration limit should be 50% to 70% of the target concentration to prevent the prepared concentration from deviating from the normal range. Setting the threshold too high will lead to frequent false cuts. If the lower limit is set at 90%, any small fluctuation will trigger a cut, causing frequent process interruptions and preventing normal production. Setting the threshold too low will result in delayed protection and weak effectiveness. If the lower limit is set at 10%, the concentration has already deviated significantly from the target value, the film quality has been damaged, and the cut is too late. 50% to 70% is a balance point. When the concentration is 50% to 70% below the target value, it means that there is a significant abnormality in the gas supply system (such as MFC jamming, bubbler temperature instability, or pipeline blockage), but it has not yet caused the film to be completely scrapped. At this time, the gas supply should be cut off to protect the current batch of wafers and at the same time to give the engineers a clear fault signal.

[0095] If the real-time concentration exceeds the preset upper limit or falls below the preset lower limit, the concentration limit determination unit outputs a cut-off trigger signal to the normally closed pneumatic shut-off valve on the optical chamber output pipeline. Upon receiving the cut-off trigger signal, the safety interlock unit on the normally closed pneumatic shut-off valve simultaneously executes the corresponding control logic.

[0096] In this embodiment, autonomous detection and rapid shut-off of concentration exceeding limits are achieved. When the limit is exceeded, the normally closed pneumatic shut-off valve is directly triggered without the need for a host computer. Compared to existing non-dispersive infrared gas detection systems that only output concentration signals and require external judgment, this embodiment reduces the safety response time from seconds to milliseconds, upgrading from passive alarm to active security, effectively ensuring the safety of using highly toxic precursors.

[0097] In some optional implementations, the signal processing module further includes a safety interlock unit; the safety interlock unit is connected to the output of the concentration exceeding the limit determination unit; The safety interlock unit is used to output a process pause command to the process control system of the MOCVD equipment, a carrier gas switching command to the carrier gas supply system of the MOCVD equipment, and an emergency discharge command to the exhaust system of the MOCVD equipment when a cut-off trigger signal is received. The carrier gas switching command is used to switch the carrier gas to inert purge gas.

[0098] Specifically, the signal processing module also includes a safety interlock unit, which is operatively coupled to the output of the concentration exceeding the limit determination unit. The safety interlock unit is used for multi-channel parallel safety response, simultaneously outputting a pause command to the process control system, a carrier gas switching command to the carrier gas supply system, and an emergency discharge command to the exhaust system.

[0099] Upon receiving a cut-off trigger signal from the concentration exceeding the limit determination unit, the safety interlock unit, in response to the received cut-off trigger signal, simultaneously performs the following control operations: outputs a process pause command to the process control system of the MOCVD equipment; outputs a carrier gas switching command to the carrier gas supply system of the MOCVD equipment, the carrier gas switching command being configured to switch the carrier gas to inert purge gas; and outputs an emergency discharge command to the exhaust system of the MOCVD equipment.

[0100] In this embodiment, multiple parallel safety linkages are implemented when the concentration exceeds the limit, simultaneously executing process suspension, switching of carrier gas to inert purging, and emergency discharge, without the need for manual intervention or host computer intervention. Compared to existing non-dispersive infrared gas detection technologies that only measure concentration and rely on external systems for judgment and handling, which are slow and limited to a single point, this embodiment improves the response speed and system safety of precursor accidents.

[0101] In some alternative implementations, the wavelength of the detected infrared light is included in the overlapping region of the characteristic absorption spectra of the second target gas component and the third target gas component in the gas to be detected.

[0102] Specifically, the infrared light source module includes a wavelength-tunable quantum cascade laser. The wavelength of the detection infrared light generated by the laser is contained in the overlapping region of the characteristic absorption spectra of the second target gas component and the third target gas component in the gas to be detected. Furthermore, the locked wavelength of the detection infrared light generated by the laser can be switched between the overlapping regions of the characteristic absorption spectra of the first target gas and the second target gas in the precursor gas to be tested.

[0103] In some alternative embodiments, the gas to be detected is at least two organometallic compounds or hydride precursors that have structural asymmetry and whose corresponding infrared absorption spectra overlap.

[0104] Specifically, the precursor gas to be tested is at least two organometallic compounds or hydride precursors with structural asymmetry and overlapping infrared absorption spectra.

[0105] At least two organometallic or hydride precursors are selected from at least two of the following: Group V hydride precursors and Group III organometallic precursors. The Group V hydride precursor is selected from at least one of arsine, phosphine, ammonia, and antimonyne; the Group III organometallic precursor is selected from at least one of trimethylgallium, trimethylaluminum, trimethylindium, triethylgallium, and diethylzinc.

[0106] According to an embodiment of the present invention, a nondispersive infrared gas detection method embodiment is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0107] This embodiment provides a nondispersive infrared gas detection method, which can be used in the aforementioned nondispersive infrared gas detection system. Figure 6 This is a flowchart of a nondispersive infrared gas detection method according to an embodiment of the present invention, such as... Figure 6 As shown, the process includes the following steps: Step S601: Generate detection infrared light of the target wavelength and shoot the detection infrared light into the optical gas cell, wherein the optical gas cell is used to pass through the gas to be detected, the gas to be detected contains multiple gas components.

[0108] Specifically, the target wavelength is, for example, the wavelength in the characteristic absorption spectral region of the precursor gas to be tested, such as the ν1 / ν3 vibrational band of arsine (1960–2260 cm⁻¹). - ¹) with the ν1 / ν3 vibrational band of phosphine (2264–2288 cm) - The overlapping area of ​​¹). The infrared light source module will detect infrared light entering the optical gas cell.

[0109] Step S602: Switch the polarization state of the detected infrared light between a first preset polarization state and a second preset polarization state according to a preset frequency.

[0110] Specifically, the first preset polarization state is, for example, a left-handed circularly polarized state. The second preset polarization state is, for example, a right-handed circularly polarized state. The preset frequency is, for example, frequency f0, with a value ranging from 100 kHz to 1 MHz. An electro-optic polarization modulator is positioned between the infrared light source module and the optical gas cell. The electro-optic polarization modulator switches between the first and second preset polarization states to detect the polarization state of the infrared light according to the aforementioned preset frequency. The electro-optic polarization modulator causes LCP and RCP to alternately pass through the optical gas cell, interacting with the arsine and phosphine mixture therein. Due to differences in molecular structural asymmetry, arsine and phosphine exhibit different degrees of selective absorption of LCP / RCP (circular dichroism difference).

[0111] Step S603: Absorb the detected infrared light and generate a non-uniform heat distribution based on the detected infrared light.

[0112] Specifically, the semiconductor circular dichroism absorption layer is disposed after the exit window of the optical gas cell and is made of a semiconductor material with circular dichroism effect. The semiconductor circular dichroism absorption layer is configured to absorb the detection infrared light in the left-hand circular polarization state and the right-hand circular polarization state differently, and to convert the difference between the absorbed detection infrared light in the left-hand circular polarization state and the right-hand circular polarization state into a non-uniform thermal distribution.

[0113] Step S604: Convert the non-uniform thermal distribution into a spin current.

[0114] Specifically, the first conversion layer, for example, is a spin-thermal conversion layer disposed beneath the semiconductor circular dichroism absorption layer. The first conversion layer is configured to convert non-uniform heat distribution into spin current. For example, the non-uniform heat distribution is transferred to the spin-thermal conversion layer through an alumina thermal isolation layer, and the spin Seebeck effect in the spin-thermal conversion layer converts the thermal gradient into a directional spin current. The thermal gradient is the rate of change of heat distribution in space, i.e., the rate of change of temperature with respect to distance; heat distribution refers to the spatial distribution of temperature; the thermal gradient is the spatial derivative of the heat distribution, reflecting the magnitude of the driving force for heat flow in a certain direction. A thermal gradient exists only when there is a non-uniform heat distribution (different temperatures in space) (heat flows from high-temperature areas to low-temperature areas); if the heat distribution is uniform (i.e., the temperature is the same everywhere), the thermal gradient is zero.

[0115] Step S605: Convert the spin current into a transverse voltage signal.

[0116] Specifically, the second conversion layer is, for example, a spin-charge conversion layer (Pt / β-W), disposed below the first conversion layer. The second conversion layer has a pair of lateral electrodes and is configured to convert the spin current into a lateral voltage signal. The inverse spin Hall effect in the second conversion layer converts the spin current into a lateral voltage signal. The frequency of the lateral voltage signal is f0 (AC signal), and its amplitude is related to the concentration difference between arsine and phosphine.

[0117] Step S606: Extract the polarization response signal from the transverse voltage signal according to the preset frequency, determine the total light intensity attenuation of the detected infrared light using the light intensity detection channel, and determine the absorption signal based on the total light intensity attenuation.

[0118] Specifically, the signal processing module is connected to the lateral electrode pair. The signal processing module includes a lock-in amplifier, which extracts the amplitude of the component with frequency f0 in the lateral voltage signal using a preset frequency as a reference frequency, as the polarization response signal. The signal processing module also includes a light intensity detection channel configured to measure the total light intensity attenuation. The total light intensity attenuation of the detected infrared light is determined using the light intensity detection channel, and the absorption signal A is determined based on the total light intensity attenuation. For example, the lock-in amplifier extracts the amplitude of the lateral voltage signal using f0 as a reference frequency, as the polarization response signal P. High-frequency modulation keeps the signal away from the 50 / 60Hz power frequency interference and low-frequency mechanical vibration noise of the MOCVD equipment, improving the signal-to-noise ratio by >60dB.

[0119] Step S607: Determine the target concentration of at least one gaseous component in the gas to be detected based on the absorption signal and the polarization response signal.

[0120] Specifically, the signal processing module establishes an absorption signal equation based on the absorption signal and a polarization response signal equation based on the polarization response signal. The signal processing module then solves for the target concentration C of at least one gaseous component in the gas to be detected by simultaneously applying the absorption signal equation and the polarization response signal equation. i The real-time concentration of each precursor is output synchronously.

[0121] The nondispersive infrared gas detection method provided in this embodiment introduces polarization response as a new measurement dimension, expanding the one-dimensional light intensity measurement in traditional nondispersive infrared gas detection technology to a two-dimensional synchronous measurement of light intensity and polarization response. This transforms the solution for multiple precursor concentrations from underdetermined to well-determined, eliminating cross-interference. Furthermore, it does not rely on absolute light intensity, eliminating system drift: the polarization response signal originates from the relative difference between LCP and RCP, rather than the absolute value of light intensity. Factors such as light source aging and window contamination only affect the total light intensity and do not affect the extraction of the polarization response signal, fundamentally eliminating the system zero drift problem. When using nondispersive infrared gas detection technology to measure the concentration of a mixture of multiple gases, performing two-dimensional synchronous measurement of light intensity and polarization response can avoid cross-interference among multiple gases and measure the concentration of different gases separately.

[0122] Figure 7 This is a schematic diagram of the structure of an electronic device provided in an embodiment of the present invention.

[0123] The following is a detailed reference. Figure 7The diagram illustrates a structural schematic suitable for implementing an electronic device according to an embodiment of the present invention. The electronic device may include a processor 701, a memory 702, a bus 703, and a communication interface 704, through which the electronic device is connected to input devices and / or output devices.

[0124] Processor 701 may be a central processing unit, a network processor, or a combination thereof. Processor 701 may further include an integrated circuit. The integrated circuit may be an application-specific integrated circuit (ASIC), a programmable logic device (PLD), or a combination thereof. The programmable logic device may be a complex programmable logic device (CAMP), a field-programmable gate array (FPGA), a general-purpose array logic (GPRS), or any combination thereof. Processor 701 can perform various appropriate actions and processes according to programs stored in memory 702. Memory 702 also stores various programs and data required for the operation of the electronic device.

[0125] The memory 702 may include a program storage area and a data storage area. The program storage area may store the operating system and application programs required for at least one function; the data storage area may store data created based on the use of the electronic device. Furthermore, the memory 702 may include volatile memory, such as random access memory; the memory may also include non-volatile memory, such as flash memory, hard disk, or solid-state drive; the memory 702 may also include combinations of the above types of memory. The processor 701, memory 702, and communication interface 704 are interconnected via bus 703. The memory 702 can receive data input from input devices via bus 703 and communication interface 704, or transmit data to output devices via bus 703 and communication interface 704. Typically, input devices can be connected to communication interface 704 to input data into the electronic device; input devices include touchscreens, touchpads, keyboards, mice, cameras, microphones, accelerometers, gyroscopes, etc.; output devices can be connected to communication interface 704 to acquire data from the electronic device; output devices include liquid crystal displays, speakers, vibrators, etc. Although... Figure 7 Electronic devices with various devices are shown, but it should be understood that it is not required to implement or have all of the devices shown, and more or fewer devices may be implemented or have instead.

[0126] In particular, according to embodiments of the present invention, the processes described above with reference to the flowcharts can be implemented as computer software programs. For example, embodiments of the present invention include a computer program product comprising a computer program carried on a non-transitory computer-readable medium, the computer program containing program code for performing the methods shown in the flowcharts. In such embodiments, the computer program can be installed to an electronic device via an input device or according to an installation package in memory 702. When the computer program is executed by processor 701, it performs the functions defined in the nondispersive infrared gas detection method of the embodiments of the present invention.

[0127] Figure 7 The electronic device shown is merely an example and should not be construed as limiting the functionality and scope of the embodiments of the present invention.

[0128] This invention also provides a computer-readable storage medium. The methods described above according to embodiments of the invention can be implemented in hardware or firmware, or implemented as computer code that can be recorded on a storage medium, or implemented as computer code downloaded via a network and originally stored on a remote storage medium or a non-transitory machine-readable storage medium and then stored on a local storage medium. Thus, the methods described herein can be processed by software stored on a storage medium using a general-purpose computer, a dedicated processor, or programmable or dedicated hardware. The storage medium can be a magnetic disk, optical disk, read-only memory, random access memory, flash memory, hard disk, or solid-state drive, etc.; further, the storage medium can also include combinations of the above types of memory. It is understood that computers, processors, microprocessor controllers, or programmable hardware include storage components capable of storing or receiving software or computer code. When the software or computer code is accessed and executed by the computer, processor, or hardware, the non-dispersive infrared gas detection method shown in the above embodiments is implemented.

[0129] Although embodiments of the invention have been described in conjunction with the accompanying drawings, those skilled in the art can make various modifications and variations without departing from the spirit and scope of the invention, and such modifications and variations all fall within the scope defined by the appended claims.

Claims

1. A non-dispersive infrared gas detection system, installed beside the inlet gas path of an MOCVD equipment, characterized in that, The system includes: An optical gas cell for passing a gas to be detected, wherein the gas to be detected contains multiple gas components; An infrared light source module is used to generate detection infrared light of the target wavelength and to project the detection infrared light into the optical gas chamber; An electro-optic polarization modulator is disposed between the infrared light source module and the optical gas cell. The electro-optic polarization modulator is used to switch the polarization state of the detected infrared light between a first preset polarization state and a second preset polarization state according to a preset frequency. A semiconductor circular dichroic absorption layer is disposed after the exit window of the optical gas cell to absorb the detected infrared light and generate a non-uniform thermal distribution based on the detected infrared light. A first conversion layer is disposed below the semiconductor circular dichroic absorption layer and is used to convert the non-uniform thermal distribution into a spin current. A second conversion layer is disposed below the first conversion layer and is used to convert the spin current into a transverse voltage signal according to the transverse electrode pair, wherein the transverse electrode is contained in the second conversion layer; The signal processing module, connected to the transverse electrode pair, is used to extract the polarization response signal from the transverse voltage signal according to the preset frequency, determine the total light intensity attenuation of the detected infrared light using the light intensity detection channel, and determine the absorption signal based on the total light intensity attenuation. The signal processing module is further configured to determine the target concentration of at least one gaseous component in the gas to be detected based on the absorption signal and the polarization response signal.

2. The system according to claim 1, characterized in that, The system also includes: a controller; The controller is connected to the concentration output terminal of the signal processing module, the mass flow controller of the MOCVD equipment, and the bubbler temperature controller of the MOCVD equipment, and is used to determine the concentration deviation between the target concentration and the corresponding preset concentration setting value; The controller is also configured to output a flow rate adjustment signal to the mass flow controller and a temperature adjustment signal to the bubbler temperature controller based on the concentration deviation.

3. The system according to claim 1, characterized in that, The signal processing module includes: a precursor delivery status detection unit; The precursor delivery status detection unit is connected to the concentration output terminal of the signal processing module, and is used to acquire the concentration signal corresponding to the target concentration, perform statistical processing on the concentration signal, and obtain the standard deviation and drift trend characteristics of the concentration signal within a preset time window. The precursor delivery status detection unit is also used to compare the standard deviation with the preset control upper limit, obtain the comparison result, and determine whether the target concentration is under statistical control based on the comparison result and the sign of the drift trend feature. The precursor delivery status detection unit is also used to output a process abnormality warning signal when it is determined that the target concentration is not in a statistically controlled state.

4. The system according to claim 1, characterized in that, The signal processing module further includes: a precursor source container inventory tracking unit; The precursor source container inventory tracking unit is connected to the concentration output terminal of the signal processing module and the carrier gas flow monitoring terminal of the MOCVD equipment. It is used to acquire the concentration signal corresponding to the concentration output terminal and the carrier gas flow monitoring terminal and to perform time integration on the concentration signal and the carrier gas flow signal to obtain the cumulative molar amount of gas component consumed corresponding to the target concentration. The precursor source container inventory tracking unit is also used to calculate the remaining usable proportion of the precursor source container based on the ratio of the cumulative consumed moles to the preset loaded moles of the precursor source container. The precursor source container inventory tracking unit is also used to output a replacement scheduling signal for the precursor source container when the remaining available ratio is less than a preset replacement threshold.

5. The system according to claim 1, characterized in that, The semiconductor circular dichroic absorption layer exhibits a circular dichroic response in the characteristic absorption spectral region of the gas to be detected, and the anisotropy factor of the circular dichroic response is 10. - ³ to 10 - ²; The first conversion layer is made of a magnetic insulating material and is used to convert the non-uniform heat distribution into the spin current through the spin Seebeck effect.

6. The system according to claim 2, characterized in that, The second conversion layer is made of a material with a spin Hall effect, used to convert the spin current into the transverse voltage signal through the inverse spin Hall effect; The preset frequency is from 100kHz to 1MHz, and the preset frequency is greater than the frequency of temperature fluctuation in the bubbler of the MOCVD equipment. The polarization extinction ratio of the electro-optic polarization modulator is greater than 30 dB; The optical path length of the optical cell is 10 to 30 meters.

7. The system according to claim 1, characterized in that, The optical chamber includes: a back pressure regulator and a heating jacket; The back pressure regulator is used to control the pressure of the optical air chamber within a preset pressure range; The heating jacket is used to control the temperature of the optical chamber within a preset temperature range.

8. The system according to claim 1, characterized in that, The signal processing module is further configured to establish an absorption signal equation based on the absorption signal and a polarization response signal equation based on the polarization response signal. The absorption signal equation satisfies: ,in, This represents the total absorption value. This represents the absorption coefficient of target gas component i. This indicates the concentration of target gas component i. Indicates optical path length; The polarization response signal equation satisfies: ,in, This represents the total polarization response value. The polarization response coefficient represents the target gas component i; The signal processing module is also used to combine the absorption signal equation and the polarization response signal equation to determine the target concentration of at least one gas component in the gas to be detected.

9. The system according to claim 8, characterized in that, The signal processing module also includes an in-situ calibration unit; The in-situ calibration unit is connected to the optical gas chamber and the standard gas source; The in-situ calibration unit is used to switch the input pipeline of the optical gas chamber from being connected to the output pipeline of the bubbler of the MOCVD equipment to being connected to the standard gas source during the non-process period of the MOCVD equipment. The in-situ calibration unit is also used to introduce a standard gas of known concentration into the optical gas cell using the standard gas source, and to obtain the measured absorption signal and the measured polarization response signal of the standard gas. The in-situ calibration unit is also used to update the absorption coefficient in the absorption signal equation based on the measured absorption signal. The polarization response coefficients in the polarization response signal equation are updated based on the measured polarization response signal. .

10. The system according to claim 1, characterized in that, The output pipeline of the optical gas chamber is equipped with a normally closed pneumatic shut-off valve; the signal processing module also includes a concentration limit exceeding determination unit, which is connected to the concentration output terminal of the signal processing module and the normally closed pneumatic shut-off valve respectively. The concentration limit determination unit is used to obtain the real-time concentration of the first target gas component and compare the real-time concentration with the preset upper limit value and the preset lower limit value respectively. The concentration limit determination unit is also used to output a cut-off trigger signal to the normally closed pneumatic shut-off valve when the real-time concentration exceeds the preset upper limit or the real-time concentration is lower than the preset lower limit.

11. The system according to claim 10, characterized in that, The signal processing module further includes a safety interlock unit; the safety interlock unit is connected to the output terminal of the concentration exceeding the limit determination unit. The safety interlock unit is used to output a process pause command to the process control system of the MOCVD equipment, an output carrier gas switching command to the carrier gas supply system of the MOCVD equipment, and an emergency discharge command to the exhaust system of the MOCVD equipment when the cut-off trigger signal is received. The carrier gas switching command is used to switch the carrier gas to inert purge gas.

12. The system according to claim 1, characterized in that, The wavelength of the detected infrared light includes the overlapping region of the characteristic absorption spectra of the second target gas component and the third target gas component in the gas to be detected.

13. The system according to claim 1, characterized in that, The gas to be detected consists of at least two organometallic compounds or hydride precursors that have structural asymmetry and whose corresponding infrared absorption spectra overlap.

14. A nondispersive infrared gas detection method, characterized in that, The method is applied to the nondispersive infrared gas detection system according to any one of claims 1 to 13, and the method includes: Detection infrared light of the target wavelength is generated and the detection infrared light is shone into an optical gas cell, wherein the optical gas cell is used to pass through a gas to be detected, the gas to be detected containing multiple gas components; The polarization state of the detected infrared light is switched between a first preset polarization state and a second preset polarization state according to a preset frequency; The infrared light being detected is absorbed, and a non-uniform thermal distribution is generated based on the infrared light being detected. The non-uniform thermal distribution is converted into a spin current; The spin current is converted into a transverse voltage signal; According to the preset frequency, the polarization response signal is extracted from the transverse voltage signal, the total light intensity attenuation of the detected infrared light is determined using the light intensity detection channel, and the absorption signal is determined based on the total light intensity attenuation. The target concentration of at least one gaseous component in the gas to be detected is determined based on the absorption signal and the polarization response signal.

15. An electronic device, characterized in that, include: The system includes a memory and a processor, which are interconnected. The memory stores computer instructions, and the processor executes the computer instructions to perform the nondispersive infrared gas detection method of claim 14.

16. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions for causing a computer to perform the nondispersive infrared gas detection method of claim 14.

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