Semiconductor gaseous molecular pollutant high-coverage detection mass spectrum device and method

Abstract

The invention relates to the technical field of semiconductor preparation, in particular to a semiconductor gaseous molecular pollutant high-coverage detection mass spectrum device and method. The device comprises a quasi-normal-pressure chemical ionization cavity, a differential transmission cavity, a low-pressure chemical ionization cavity and a mass analyzer which are sequentially connected in series, wherein vacuum difference is realized among the cavities through three ion extraction electrodes; the quasi-normal-pressure chemical ionization cavity performs chemical reaction ionization on polar components of sample gas through first reagent ions and transmits the first reagent ions and the polar components of the sample gas; the differential transmission cavity is used for efficiently transmitting the ionized sample; and the low-pressure chemical ionization cavity carries out low-pressure chemical ionization on the non-polar or weak-polar neutral sample which is not ionized through second reagent ions, and the second reagent ions are efficiently transmitted into the mass analyzer for mass spectrometric detection. According to the invention, the coupling of the quasi-normal-pressure chemical ionization source and the low-pressure chemical ionization source is realized through the multi-stage vacuum differential design, so that the non-polar or polar trace AMC compounds in the semiconductor can be detected with high sensitivity and high coverage.

Description

Technical Field

[0001] This invention relates to the field of semiconductor fabrication technology, and in particular to a high-coverage mass spectrometry device and method for detecting gaseous molecular contaminants in semiconductors. Background Technology

[0002] Semiconductor manufacturing encompasses thousands of chips and hundreds of thousands of components, supporting a global digital economy with an annual output value of trillions of dollars. Airborne molecular contamination (AMC) is a collective term for trace amounts of gaseous molecular contaminants that can negatively impact semiconductor manufacturing yield. As semiconductor processes approach the molar limit, with nanometer (nm) scale etching dimensions and higher transistor densities, AMC-induced problems will continuously propagate and amplify, reducing wafer yield. Accurate measurement of AMC types and concentrations is a prerequisite for studying their control and impact mechanisms. By establishing a correlation model between AMCs and wafer defects, AMCs can be targeted for control, improving wafer yield. Furthermore, identifying the sources of AMCs can assist in optimizing processes and materials, exploring their impact on photolithography and performance, and achieving breakthroughs in advanced process technologies. However, AMC concentrations are extremely low (pptv ~ ppbv) and their composition is complex, including acids, bases, agglomerated organic matter, dopants, etc. As process nodes become smaller and concentration control becomes more stringent, accurate qualitative and quantitative methods for AMCs face significant challenges. Currently, techniques such as thermal desorption / mass spectrometry, cavity ring-down spectroscopy, soft X-ray detectors, and ion mobility spectrometry (IMS) have been used for online AMC monitoring in semiconductor cleanrooms. However, these techniques generally suffer from long analysis times or limited detection species coverage. Chemical ionization mass spectrometry (CIEMS) is an online, highly sensitive measurement technique with advantages such as fast analysis speed, strong qualitative capabilities, and a wide detection range. However, it still struggles to simultaneously achieve highly sensitive and comprehensive detection of both polar and nonpolar trace compounds.

[0003] A search of patents and papers revealed the following relevant patents concerning high-coverage ionization and chemical ionization in mass spectrometers: The Dalian Institute of Chemical Physics, Chinese Academy of Sciences, disclosed a high-coverage polarity-switching ionization source on May 23, 2023. This source controls different ionization modes through flow rate, pressure, and voltage, improving the coverage of the mass spectrometer for detecting complex samples. Shandong University disclosed a pressure-controlled photoelectron ionization and chemical ionization switching system and method on August 25, 2023. This system regulates the ionization source pressure through flow rate switching and switchable central aperture, enabling photoelectron ionization at low pressure and chemical ionization at medium pressure. However, both patents suffer from cumbersome switching methods, long switching times, and the ability to operate only in a single mode after switching, making it difficult to truly achieve real-time monitoring of multi-component compounds. Therefore, there is an urgent need to develop high-coverage, high-sensitivity ionization detection mass spectrometry devices and methods to achieve real-time monitoring of multi-component trace gaseous molecular contaminants during semiconductor manufacturing. Summary of the Invention

[0004] To address the problems existing in the prior art, the present invention aims to provide a high-coverage mass spectrometry device and method for detecting gaseous molecular contaminants in semiconductors, so as to solve the problem of real-time monitoring of trace gaseous molecular contaminants of multiple components in the semiconductor manufacturing process.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The present invention provides a high-coverage mass spectrometry device for detecting semiconductor gaseous molecular pollutants, comprising a quasi-atmospheric pressure chemical ionization cavity, a differential transmission cavity, a low-pressure chemical ionization cavity and a mass analyzer connected in series along the X direction, and vacuum differential is achieved between the cavities by a first ion extraction electrode, a second ion extraction electrode and a third ion extraction electrode in the shape of a plate with a through hole in the middle.

[0007] The quasi-atmospheric pressure chemical ionization chamber is used to directly photoionize the first reagent gas and to chemically react the generated first reagent ions with the polar components of the introduced sample gas to ionize them, and then transmit them to the differential transmission chamber under the action of the first ion extraction electrode.

[0008] The differential transmission cavity is used for efficient transmission of ionized samples and passes through the second ion extraction electrode into the low-pressure chemical ionization cavity.

[0009] The low-pressure chemical ionization chamber is used to ionize the second reagent gas. The generated second reagent ions are chemically ionized at low pressure with the non-polar or weakly polar neutral sample that has not been ionized in the region. Finally, together with the polar product ions generated in the quasi-atmospheric pressure chemical ionization chamber and transported to the region, they pass through the central hole of the third ion extraction electrode and are efficiently transported to the mass analyzer.

[0010] Mass analyzers are used for mass spectrometry detection.

[0011] The quasi-atmospheric pressure chemical ionization cavity is equipped with an electrostatic reaction electrode group, and a first vacuum ultraviolet light source is provided on the other side of the quasi-atmospheric pressure chemical ionization cavity away from the first ion extraction electrode. The first vacuum ultraviolet light source is used to emit ultraviolet light.

[0012] The electrostatic reaction electrode assembly includes two or more spaced and insulated plate-shaped electrodes, each plate-shaped electrode having a coaxial central hole; the central holes of the first vacuum ultraviolet light source, the electrostatic reaction electrode assembly, and the first ion extraction electrode are placed coaxially.

[0013] The quasi-atmospheric pressure chemical ionization chamber is provided with a sample inlet tube and a first reagent gas inlet tube on its upper and lower sides, respectively. The outlet ends of the sample inlet tube and the first reagent gas inlet tube are placed between the first two plate-shaped electrodes in the electrostatic reaction electrode group.

[0014] The electrostatic reaction electrode group is composed of a uniform electrostatic field reaction region consisting of plate-shaped electrodes with the same inner diameter central hole; or the electrostatic reaction electrode group is composed of an electrostatic field or radio frequency field ion reaction region consisting of plate-shaped electrodes with successively decreasing inner diameter central hole.

[0015] The differential transmission cavity is equipped with a funnel-shaped radio frequency transmission module, which includes three or more flat plates with a central hole in the middle. The three or more flat plates are placed coaxially, spaced apart and insulated from each other along the X direction, and the diameter of the central hole decreases sequentially along the X direction. The second ion extraction electrode is coaxially placed on the right side of the funnel-shaped radio frequency transmission module and spaced apart.

[0016] The funnel-shaped radio frequency transmission module is composed of a conventional ion funnel consisting of a plate-shaped electrode with a gradually decreasing inner diameter of the central hole; or the funnel-shaped radio frequency transmission module is composed of a funnel-shaped hexapole, octapole, or dodecapole.

[0017] The low-pressure chemical ionization cavity is equipped with a second vacuum ultraviolet light source and a radio frequency focused ion molecular reaction module, wherein the radio frequency focused ion molecular reaction module includes two or more radio frequency sub-modules that are coaxial with the second ion extraction electrode and the third ion extraction electrode and are arranged at intervals.

[0018] The light emitted from the second vacuum ultraviolet light source is perpendicular to the X-direction, and the light shines between the first two radio frequency sub-modules of the radio frequency focused ion molecular reaction module to ionize the second reagent gas.

[0019] A second reagent gas inlet line is provided on one side of the low-pressure chemical ionization chamber. The outlet end of the second reagent gas inlet line is located between the first two radio frequency sub-modules of the radio frequency focused ion molecular reaction module. The radio frequency sub-module is used for low-pressure chemical ionization of the second reagent ions with non-polar or weakly polar neutral samples that have not been ionized in the region.

[0020] The radio frequency focused ion molecular reaction module is composed of a radio frequency sub-module consisting of a flat electrode with through holes of the same inner diameter; or the radio frequency focused ion molecular reaction module is composed of a segmented quadrupole, hexapole, or octapole capable of providing an axial electric field.

[0021] The mass analyzer is a time-of-flight mass analyzer, a quadrupole mass analyzer, or an ion trap mass analyzer.

[0022] The quasi-atmospheric pressure chemical ionization chamber is connected to a diaphragm pump via a suction line. The diaphragm pump is used to maintain the gas pressure inside the quasi-atmospheric pressure chemical ionization chamber, and the working gas pressure of the quasi-atmospheric pressure chemical ionization chamber is 10. 4 ~10 5 Pa level;

[0023] The differential transmission chamber is connected to a first mechanical pump via an air extraction pipe. The first mechanical pump is used to maintain the air pressure inside the differential transmission chamber. The operating air pressure of the differential transmission chamber is 10. 3 Pa level;

[0024] The low-pressure chemical ionization chamber is connected to a second mechanical pump via a suction pipe. The second mechanical pump is used to maintain the gas pressure inside the low-pressure chemical ionization chamber. The operating gas pressure of the low-pressure chemical ionization chamber is 10. 2 Pa level.

[0025] Another aspect of the present invention provides a method for high-coverage detection of semiconductor gaseous molecular contaminants using mass spectrometry with the apparatus described above, comprising the following steps:

[0026] Step S1: Adjust the quasi-atmospheric pressure chemical ionization chamber, differential transmission chamber, and low-pressure chemical ionization chamber to the working pressure;

[0027] Step S2: The first reagent gas and the sample gas are introduced into the quasi-atmospheric pressure chemical ionization chamber through the first reagent gas inlet tube and the sample inlet tube, respectively. The photons generated by the first vacuum ultraviolet light source directly photoionize the first reagent gas. The generated first reagent ions react chemically with the polar components in the introduced sample gas under the action of the electrostatic reaction electrode group and are ionized, and are transported to the differential transmission chamber under the action of the first ion extraction electrode.

[0028] Step S3: The differential transmission cavity efficiently transmits the ionized sample through the second ion extraction electrode into the low-pressure chemical ionization cavity; at the same time, the unionized non-polar neutral sample passes through the differential transmission cavity into the low-pressure chemical ionization cavity under vacuum differential action.

[0029] Step S4: The second reagent gas is introduced into the low-pressure chemical ionization chamber through the second reagent gas inlet pipeline; the second vacuum ultraviolet light source in the low-pressure chemical ionization chamber first ionizes the second reagent gas to generate corresponding second reagent ions. Under the action of the radio frequency focused ion molecular reaction module, the second reagent ions undergo low-pressure chemical ionization with the unionized nonpolar or weakly polar neutral sample entering the region, and finally pass through the small hole in the center of the third ion extraction electrode together with the polar product ions generated in the quasi-atmospheric pressure chemical ionization chamber and transported to the region, and are efficiently transported to the mass analyzer for detection.

[0030] The advantages and beneficial effects of this invention are as follows: This invention achieves the coupling of quasi-atmospheric pressure and low-pressure chemical ionization sources through multi-stage vacuum differential design, enabling high-sensitivity and high-coverage detection of trace AMC compounds from nonpolar to polar in semiconductors, and has good application prospects in trace AMC monitoring in semiconductor manufacturing processes.

[0031] Other features and advantages of the invention will be set forth in the following description, and will be apparent in part from the description, or may be learned by practicing the invention. The objects and other advantages of the invention may be realized and obtained by means of the structures particularly pointed out in the written description and the accompanying drawings.

[0032] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0033] The accompanying drawings are provided to further illustrate the invention and form part of the specification. They are used in conjunction with embodiments of the invention to explain the invention and do not constitute a limitation thereof. In the drawings:

[0034] Figure 1 This is a schematic diagram of the structure of a high-coverage mass spectrometry device for detecting semiconductor gaseous molecular pollutants according to the present invention.

[0035] In the figure: 1 is the first vacuum ultraviolet light source; 2 is the quasi-atmospheric pressure chemical ionization chamber; 3 is the sample injection tube; 4 is the first ion extraction electrode; 5 is the differential transmission chamber; 6 is the funnel-shaped radio frequency transmission module; 7 is the flat plate electrode; 8 is the second ion extraction electrode; 9 is the second vacuum ultraviolet light source; 10 is the low-pressure chemical ionization chamber; 11 is the mass analyzer; 12 is the third ion extraction electrode; 13 is the radio frequency submodule; 14 is the second mechanical pump; 15 is the radio frequency focused ion molecular reaction module; 16 is the second reagent gas injection line; 17 is the first mechanical pump; 18 is the membrane pump; 19 is the first reagent gas injection line; 20 is the electrostatic reaction electrode group. Detailed Implementation

[0036] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0037] The preferred embodiments of the present invention will be described below with reference to the accompanying drawings. It should be understood that the preferred embodiments described herein are for illustration and explanation only and are not intended to limit the present invention.

[0038] See Figure 1 As shown, an embodiment of the present invention provides a high-coverage mass spectrometry device for detecting semiconductor gaseous molecular pollutants, with the upward direction defined as the Y direction and the rightward direction as the X direction. The device includes a quasi-atmospheric pressure chemical ionization chamber 2, a differential transmission chamber 5, a low-pressure chemical ionization chamber 10, and a mass analyzer 11 connected in series along the X direction. Vacuum differential is achieved between the chambers via a plate-shaped first ion extraction electrode 4, a second ion extraction electrode 8, and a third ion extraction electrode 12 with a through-hole in the center. The quasi-atmospheric pressure chemical ionization chamber 2 is used for direct photoionization of the first reagent gas and for the generated first reagent ions to chemically react with the polar components of the introduced sample gas. The reaction ionizes and is transported to the differential transmission cavity 5 under the action of the first ion extraction electrode 4; the differential transmission cavity 5 is used to efficiently transport the ionized sample and passes through the second ion extraction electrode 8 into the low-pressure chemical ionization cavity 10; the low-pressure chemical ionization cavity 10 is used to ionize the second reagent gas, and the generated second reagent ions are subjected to low-pressure chemical ionization with the unionized nonpolar or weakly polar neutral sample entering the region, and finally pass through the central hole of the third ion extraction electrode 12 together with the polar product ions generated and transported to the region by the quasi-atmospheric pressure chemical ionization cavity 2, and are efficiently transported into the mass analyzer 11; the mass analyzer 11 is used for mass spectrometry detection.

[0039] See Figure 1 As shown, in an embodiment of the present invention, the quasi-atmospheric pressure chemical ionization chamber 2 is connected to the diaphragm pump 18 via a suction line. The diaphragm pump 18 is used to maintain the gas pressure inside the quasi-atmospheric pressure chemical ionization chamber 2, and the working gas pressure of the quasi-atmospheric pressure chemical ionization chamber 2 is 10. 4 ~10 5 The pressure is on the order of Pa. The differential transmission chamber 5 is connected to the first mechanical pump 17 via a suction line. The first mechanical pump 17 is used to maintain the air pressure inside the differential transmission chamber 5; the operating air pressure of the differential transmission chamber 5 is 10 Pa. 3The pressure is on the order of Pa; the low-pressure chemical ionization chamber 10 is connected to the second mechanical pump 14 via a suction line, and the second mechanical pump 14 is used to maintain the pressure inside the low-pressure chemical ionization chamber 10; the working pressure of the low-pressure chemical ionization chamber 10 is 10 Pa. 2 The pressure is on the order of Pa. Vacuum differential is achieved between the low-pressure chemical ionization chamber 10 and the mass analyzer 11 via a third ion extraction electrode 12.

[0040] In an embodiment of the present invention, an electrostatic reaction electrode group 20 is provided in the quasi-atmospheric pressure chemical ionization chamber 2. A first vacuum ultraviolet light source 1 is fixed and sealed on the other side (left side) of the quasi-atmospheric pressure chemical ionization chamber 2 away from the first ion extraction electrode 4. The first vacuum ultraviolet light source 1 is used to emit ultraviolet light. The electrostatic reaction electrode group 20 includes two or more spaced and insulated plate-shaped electrodes, each plate-shaped electrode having a coaxial central hole. The first ion extraction electrode 4 is a plate structure with a through hole in the center, placed on the right side of the electrostatic reaction electrode group 20 and spaced apart. The central holes of the first vacuum ultraviolet light source 1, the electrostatic reaction electrode group 20 and the first ion extraction electrode 4 are placed coaxially.

[0041] Furthermore, the upper and lower sides of the quasi-atmospheric pressure chemical ionization chamber 2 are respectively provided with a sample inlet tube 3 and a first reagent gas inlet tube 19 passing through the chamber wall. The outlet ends of the sample inlet tube 3 and the first reagent gas inlet tube 19 are placed between the first two flat electrodes in the electrostatic reaction electrode assembly 20. The outer walls of the sample inlet tube 3 and the first reagent gas inlet tube 19 are sealed to the wall of the quasi-atmospheric pressure chemical ionization chamber 2.

[0042] Furthermore, the electrostatic reaction electrode group 20 is composed of plate-shaped electrodes with the same inner diameter central hole forming a uniform electrostatic field reaction region; or the electrostatic reaction electrode group 20 is composed of plate-shaped electrodes with successively decreasing inner diameter central holes forming an electrostatic field or radio frequency field ion reaction region.

[0043] Preferably, the electrostatic reaction electrode group 20 is composed of a radio frequency field ion reaction region consisting of plate-shaped electrodes with progressively decreasing inner diameters, which has higher ion transport efficiency.

[0044] In an embodiment of the present invention, a funnel-shaped radio frequency transmission module 6 is provided in the differential transmission cavity 5. The funnel-shaped radio frequency transmission module 6 includes three or more plate-shaped electrodes 7 with a central hole in the middle. The three or more plate-shaped electrodes 7 are placed coaxially, spaced apart and insulated along the X direction, and the diameter of the central hole decreases sequentially along the X direction. The second ion extraction electrode 8 is a plate structure with a through hole in the center, which is placed on the right side of the funnel-shaped radio frequency transmission module 6 and is placed at intervals and coaxially with the central hole.

[0045] Furthermore, the funnel-shaped radio frequency transmission module 6 is composed of a conventional ion funnel consisting of a plate-shaped electrode with a gradually decreasing inner diameter of the central hole; or the funnel-shaped radio frequency transmission module 6 is composed of multi-pole components such as funnel-shaped hexapole, octapole, or dodecapole.

[0046] Preferably, the funnel-shaped radio frequency transmission module 6 is composed of a funnel-shaped octupole, which is simpler than the traditional ion funnel structure and takes into account both a wide mass range and ion transmission efficiency.

[0047] In an embodiment of the present invention, a second vacuum ultraviolet light source 9 and a radio frequency focused ion molecular reaction module 15 are provided in the low-pressure chemical ionization chamber 10. The radio frequency focused ion molecular reaction module 15 includes two or more radio frequency sub-modules 13 arranged coaxially and spaced apart from the second ion extraction electrode 8 and the third ion extraction electrode 12. The light emission direction of the second vacuum ultraviolet light source 9 is perpendicular to the X-direction, and the light irradiates the area between the first two radio frequency sub-modules 13 of the radio frequency focused ion molecular reaction module 15 to ionize the second reagent gas. The third ion extraction electrode 12 is a flat plate structure with a central through hole, placed on the right side of the radio frequency focused ion molecular reaction module 15 and spaced apart, with the central hole coaxial.

[0048] Furthermore, a second reagent gas inlet line 16 is provided on one side of the low-pressure chemical ionization chamber 10, and the outlet end of the second reagent gas inlet line 16 is located between the first two radio frequency sub-modules 13 of the radio frequency focused ion molecular reaction module 15; the radio frequency sub-module 13 is used for low-pressure chemical ionization of the second reagent ions with the non-polar or weakly polar neutral samples that have not been ionized in the region.

[0049] Furthermore, the radio frequency focused ion molecular reaction module 15 is composed of a radio frequency sub-module 13 with a plate-shaped electrode having the same inner diameter through hole; or the radio frequency focused ion molecular reaction module 15 is composed of a segmented quadrupole, hexapole, or octapole that can provide an axial electric field.

[0050] Preferably, the radio frequency focused ion molecular reaction module 15 is composed of a segmented quadrupole that can provide an axial electric field, which has a better ion focusing effect and can further improve sensitivity.

[0051] Furthermore, the first vacuum ultraviolet light source 1 and the second vacuum ultraviolet light source 9 are one or two of the following: gas discharge lamp light source, laser light source, or synchrotron radiation light source.

[0052] Preferably, the first vacuum ultraviolet light source 1 and the second vacuum ultraviolet light source 9 are selected gas discharge lamp light sources with small size and low power consumption.

[0053] Furthermore, the mass analyzer 11 is a time-of-flight mass analyzer, a quadrupole mass analyzer, or an ion trap mass analyzer.

[0054] Preferably, the quality analyzer 11 is a time-of-flight quality analyzer, which has a wider quality range and higher resolution, helping to improve the analysis range and qualitative accuracy.

[0055] Furthermore, the sample inlet tube 3, the first reagent gas inlet line 19, and the second reagent gas inlet line 16 can be made of one or more of the following materials: metal or non-metal, such as stainless steel, aluminum alloy or copper, PEEK, PTFE, plexiglass, etc., with an inner diameter of 0.1~2 mm and a flow rate of 1~500 mL / min.

[0056] Preferably, the sample inlet tube 3, the first reagent gas inlet line 19, and the second reagent gas inlet line 16 are all made of stainless steel; wherein the sample inlet tube 3 and the first reagent gas inlet line 19 have an inner diameter of 0.5 mm and a flow rate of 500 mL / min; the second reagent gas inlet line 16 has an inner diameter of 0.25 mm and a flow rate of 50 mL / min.

[0057] An embodiment of the present invention provides a high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants, wherein the ionization region within the quasi-atmospheric pressure chemical ionization chamber operates at 10 4 ~10 5 At 10 Pa, it is suitable for the analysis of polar compounds such as inorganic acids, organic acids, and organic amines. The generated ions and unionized neutral compounds are transported together through the differential transmission cavity to the low-pressure chemical ionization cavity; the differential transmission cavity operates at 10 Pa. 3 At Pa, it consists of a funnel-shaped radio frequency transmission module and a second ion extraction electrode; the low-pressure chemical ionization chamber operates at 10 Pa. 2 At pressure Pa, a low-pressure photoelectron ionization cavity generates weakly polar and nonpolar ions, which, together with ions introduced by the differential transmission cavity, pass through the third ion extraction electrode and are transmitted to the mass analyzer for detection. This invention achieves coupling between quasi-atmospheric pressure and low-pressure chemical ionization sources through a multi-stage vacuum differential design, enabling highly sensitive and comprehensive detection of trace AMC compounds, from nonpolar to polar, in semiconductors. This invention shows promising application prospects for trace AMC monitoring in semiconductor manufacturing processes.

[0058] Another embodiment of the present invention provides a method for high-coverage detection of semiconductor gaseous molecular contaminants using mass spectrometry with the device described above, characterized by comprising the following steps:

[0059] Step S1: Adjust the quasi-atmospheric pressure chemical ionization chamber 2, differential transmission chamber 5, and low-pressure chemical ionization chamber 10 to the working pressure;

[0060] Specifically, the pumping speeds of the diaphragm pump 18, the first mechanical pump 17, and the second mechanical pump 14 are adjusted to 10, respectively, to achieve the required speeds of the quasi-atmospheric pressure chemical ionization chamber 2, the differential transmission chamber 5, and the low-pressure chemical ionization chamber 10. 4 ~10 5 10 3 and 10 2 Pa working air pressure;

[0061] Step S2: The first reagent gas and the sample gas are introduced into the quasi-atmospheric pressure chemical ionization chamber 2 through the first reagent gas inlet tube 19 and the sample inlet tube 3, respectively. The photons generated by the first vacuum ultraviolet light source 1 directly photoionize the first reagent gas. The generated first reagent ions react chemically with the polar components such as inorganic acids, organic acids, and organic amines in the introduced sample gas under the action of the electrostatic reaction electrode group 20, and are then transported to the differential transmission chamber 5 under the action of the first ion extraction electrode 4.

[0062] Step S3: The funnel-shaped radio frequency transmission module 6 in the differential transmission cavity 5 efficiently transmits the ionized sample through the second ion extraction electrode 8 and into the low-pressure chemical ionization cavity 10; at the same time, the unionized non-polar neutral sample passes through the differential transmission cavity 5 and enters the low-pressure chemical ionization cavity 10 under vacuum differential action.

[0063] Step S4: The second reagent gas is introduced into the low-pressure chemical ionization chamber 10 through the second reagent gas inlet pipe 16. The second vacuum ultraviolet light source 9 in the low-pressure chemical ionization chamber 10 first ionizes the second reagent gas to generate corresponding second reagent ions. Under the action of the radio frequency focused ion molecular reaction module 15, the second reagent ions undergo low-pressure chemical ionization with the non-polar or weakly polar neutral sample that has not been ionized in this region. Finally, together with the polar product ions generated in the quasi-atmospheric pressure chemical ionization chamber 2 and transported to this region, they pass through the central hole of the third ion extraction electrode 12 and are efficiently transported to the mass analyzer 11 for detection.

[0064] Example 1

[0065] See Figure 1As shown, the present invention provides a pollution-carbon co-monitoring mass spectrometry ionization device. By adjusting the pumping speeds of the membrane pump 18, the first mechanical pump 17, and the second mechanical pump 14, the quasi-atmospheric pressure chemical ionization chamber 2, the differential transmission chamber 5, and the low-pressure chemical ionization chamber 10 are adjusted to working pressures of 10000 Pa, 1000 Pa, and 100 Pa, respectively. Reagent gas A and sample gas S are introduced into the quasi-atmospheric pressure chemical ionization chamber 2 through the first reagent gas inlet line 19 and the sample inlet line 3, respectively. Both the first reagent gas inlet line 19 and the sample inlet line 3 are made of stainless steel, and the flow rates are controlled at 500 m / s. mL / min; the first vacuum ultraviolet light source 1 uses a DC discharge Kr lamp, whose photons directly photoionize reagent gas A; the generated reagent A ions react chemically with the polar components such as inorganic acids, organic acids, and organic amines in the introduced sample gas under the action of the electrostatic reaction electrode group 20, and are then transmitted to the differential transmission cavity 5 under the action of the first ion extraction electrode 4; the funnel-shaped radio frequency transmission module 6 efficiently transmits the ionized sample, efficiently passing through the second ion extraction electrode 8 into the low-pressure chemical ionization cavity 10; at the same time, the unionized non-polar neutral sample passes through the differential transmission cavity 5 into the low-pressure chemical ionization cavity 10 under the action of vacuum differential; reagent gas B is introduced into the low-pressure chemical ionization cavity 10 through the second reagent gas inlet pipe 16 with an inner diameter of 0.25 mm made of stainless steel, and the flow rate is controlled at 50. mL / min; The second vacuum ultraviolet light source 9 of the low-pressure chemical ionization chamber 10 adopts a DC discharge Kr lamp to ionize the reagent gas B to generate corresponding B reagent ions. Under the action of the radio frequency focused ion molecular reaction module 15, the B reagent ions undergo low-pressure chemical ionization with the unionized non-polar or weakly polar neutral sample entering the region, and finally pass through the central hole of the third ion extraction electrode 12 together with the polar product ions generated by the quasi-atmospheric pressure chemical ionization chamber 2 and transported to the region, and are efficiently transported to the time-of-flight mass analyzer 11 for detection.

[0066] The concentration of gaseous molecular contaminants (AMCs) in semiconductor manufacturing processes is extremely low (pptv ~ ppbv), and their composition is complex, including acids, bases, condensable organic compounds, and dopants. Furthermore, as process nodes become smaller, concentration control becomes more stringent, posing significant challenges to accurate qualitative and quantitative methods for AMCs. Currently, techniques such as thermal desorption / mass spectrometry (TDS), cavity ring-down spectroscopy, soft X-ray detectors, and ion mobility spectrometry (IMS) are used for online AMC monitoring in semiconductor cleanrooms; however, these techniques generally suffer from long analysis times or limited detection species coverage. Chemical ionization mass spectrometry (CIEMS) is an online, highly sensitive measurement technique with advantages such as fast analysis speed, strong qualitative capabilities, and a wide detection range, but it still struggles to simultaneously achieve high-sensitivity, high-coverage detection of both polar and nonpolar trace compounds. This invention cleverly couples quasi-atmospheric pressure and low-pressure chemical ionization sources through a multi-stage vacuum differential design, enabling high-sensitivity, high-coverage detection of trace AMCs from nonpolar to polar sources in semiconductors, showing promising application prospects for trace AMC monitoring in semiconductor manufacturing processes.

[0067] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants, characterized in that, It includes a quasi-atmospheric pressure chemical ionization chamber (2), a differential transmission chamber (5), a low-pressure chemical ionization chamber (10), and a mass analyzer (11) connected in series along the X direction. Vacuum differential is achieved between the chambers by a first ion extraction electrode (4), a second ion extraction electrode (8), and a third ion extraction electrode (12) with a through hole in the middle. The quasi-atmospheric pressure chemical ionization chamber (2) is used to directly photoionize the first reagent gas and to chemically react the generated first reagent ions with the polar components of the introduced sample gas to ionize them, and then transmit them to the differential transmission chamber (5) under the action of the first ion extraction electrode (4). The differential transmission cavity (5) is used to efficiently transport the ionized sample and passes through the second ion extraction electrode (8) into the low-pressure chemical ionization cavity (10). The low-pressure chemical ionization chamber (10) is used to ionize the second reagent gas. The generated second reagent ions are chemically ionized at low pressure with the non-polar or weakly polar neutral sample that has not been ionized in the region. Finally, together with the polar product ions generated in the quasi-atmospheric pressure chemical ionization chamber (2) and transported to the region, they pass through the central hole of the third ion extraction electrode (12) and are efficiently transported to the mass analyzer (11). The mass analyzer (11) is used for mass spectrometry detection.

2. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 1, characterized in that, The quasi-atmospheric pressure chemical ionization chamber (2) is provided with an electrostatic reaction electrode group (20). On the other side of the quasi-atmospheric pressure chemical ionization chamber (2) away from the first ion extraction electrode (4), a first vacuum ultraviolet light source (1) is provided. The first vacuum ultraviolet light source (1) is used to emit ultraviolet light. The electrostatic reaction electrode group (20) includes two or more spaced and insulated plate-shaped electrodes, each plate-shaped electrode having a coaxial central hole; the central holes of the first vacuum ultraviolet light source (1), the electrostatic reaction electrode group (20) and the first ion extraction electrode (4) are placed coaxially. The quasi-atmospheric pressure chemical ionization chamber (2) is provided with a sample inlet tube (3) and a first reagent gas inlet tube (19) on its upper and lower sides, respectively. The outlet ends of the sample inlet tube (3) and the first reagent gas inlet tube (19) are placed between the first two flat electrodes in the electrostatic reaction electrode group (20).

3. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 2, characterized in that, The electrostatic reaction electrode group (20) is composed of plate-shaped electrodes with the same inner diameter central hole forming a uniform electrostatic field reaction zone; or the electrostatic reaction electrode group (20) is composed of plate-shaped electrodes with successively decreasing inner diameter central hole forming an electrostatic field or radio frequency field ion reaction zone.

4. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 2, characterized in that, The differential transmission cavity (5) is provided with a funnel-shaped radio frequency transmission module (6). The funnel-shaped radio frequency transmission module (6) includes three or more flat plate electrodes (7) with a central hole in the middle. The three or more flat plate electrodes (7) are placed coaxially, spaced apart and insulated along the X direction, and the diameter of the central hole decreases sequentially along the X direction. The second ion extraction electrode (8) is placed coaxially on the right side of the funnel-shaped radio frequency transmission module (6) and spaced apart.

5. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 4, characterized in that, The funnel-shaped radio frequency transmission module (6) is composed of a conventional ion funnel consisting of a plate-shaped electrode with a gradually decreasing inner diameter of the central hole; or the funnel-shaped radio frequency transmission module (6) is composed of a funnel-shaped hexapole, octapole, or dodecapole.

6. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 2, characterized in that, The low-pressure chemical ionization chamber (10) is equipped with a second vacuum ultraviolet light source (9) and a radio frequency focused ion molecular reaction module (15), wherein the radio frequency focused ion molecular reaction module (15) includes two or more radio frequency sub-modules (13) that are coaxial with the second ion extraction electrode (8) and the third ion extraction electrode (12) and are arranged at intervals. The light emission direction of the second vacuum ultraviolet light source (9) is perpendicular to the X direction, and the light irradiates the area between the first two radio frequency sub-modules (13) of the radio frequency focused ion molecular reaction module (15) to ionize the second reagent gas. The low-pressure chemical ionization chamber (10) is provided with a second reagent gas inlet pipe (16) on one side. The outlet end of the second reagent gas inlet pipe (16) is located between the first two radio frequency sub-modules (13) of the radio frequency focused ion molecular reaction module (15). The radio frequency sub-module (13) is used for low-pressure chemical ionization of the second reagent ions with the non-polar or weakly polar neutral samples that have not been ionized in the region.

7. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 6, characterized in that, The radio frequency focused ion molecular reaction module (15) is composed of a radio frequency sub-module (13) of a plate-shaped electrode with the same inner diameter through hole; or the radio frequency focused ion molecular reaction module (15) is composed of a segmented quadrupole, hexapole or octapole that can provide an axial electric field.

8. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 1, characterized in that, The mass analyzer (11) is a time-of-flight mass analyzer, a quadrupole mass analyzer, or an ion trap mass analyzer.

9. The high-coverage mass spectrometry device for detecting semiconductor gaseous molecular contaminants according to claim 1, characterized in that, The quasi-atmospheric pressure chemical ionization chamber (2) is connected to a diaphragm pump (18) via a suction line. The diaphragm pump (18) is used to maintain the gas pressure inside the quasi-atmospheric pressure chemical ionization chamber (2). The working gas pressure of the quasi-atmospheric pressure chemical ionization chamber (2) is 10. 4 ~10 5 Pa level; The differential transmission chamber (5) is connected to the first mechanical pump (17) via an air extraction pipe. The first mechanical pump (17) is used to maintain the air pressure inside the differential transmission chamber (5). The working air pressure of the differential transmission chamber (5) is 10. 3 Pa level; The low-pressure chemical ionization chamber (10) is connected to a second mechanical pump (14) via a suction pipe. The second mechanical pump (14) is used to maintain the gas pressure inside the low-pressure chemical ionization chamber (10). The working gas pressure of the low-pressure chemical ionization chamber (10) is 10. 2 Pa level.

10. A method for high-coverage mass spectrometry detection of semiconductor gaseous molecular contaminants using the apparatus as described in claim 6 or 7, characterized in that, Includes the following steps: Step S1: Adjust the quasi-atmospheric pressure chemical ionization chamber (2), differential transmission chamber (5) and low-pressure chemical ionization chamber (10) to the working pressure; Step S2: The first reagent gas and the sample gas are introduced into the quasi-atmospheric pressure chemical ionization chamber (2) through the first reagent gas inlet tube (19) and the sample inlet tube (3), respectively. The photons generated by the first vacuum ultraviolet light source (1) directly photoionize the first reagent gas. The generated first reagent ions react with the polar components in the introduced sample gas under the action of the electrostatic reaction electrode group (20) and are transported to the differential transmission chamber (5) under the action of the first ion extraction electrode (4). Step S3: The differential transmission cavity (5) efficiently transmits the ionized sample through the second ion extraction electrode (8) and into the low-pressure chemical ionization cavity (10); at the same time, the unionized non-polar neutral sample passes through the differential transmission cavity (5) and enters the low-pressure chemical ionization cavity (10) under vacuum differential action. Step S4: The second reagent gas is introduced into the low-pressure chemical ionization chamber (10) through the second reagent gas inlet pipe (16); the second vacuum ultraviolet light source (9) in the low-pressure chemical ionization chamber (10) first ionizes the second reagent gas to generate corresponding second reagent ions. Under the action of the radio frequency focused ion molecular reaction module (15), the second reagent ions undergo low-pressure chemical ionization with the non-polar or weakly polar neutral sample that has not been ionized in the region, and finally pass through the central hole of the third ion extraction electrode (12) together with the polar product ions generated in the quasi-atmospheric pressure chemical ionization chamber (2) and transmitted to the region, and are efficiently transmitted to the mass analyzer (11) for detection.

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