阅读说明：本技术 基于质谱技术的元素检测装置和方法 (Element detection device and method based on mass spectrometry technology ) 是由 陈悠 俞晓峰 徐岳 胡晓鹏 于 2021-08-18 设计创作，主要内容包括：本发明提供了基于质谱技术的元素检测装置和方法,所述基于质谱技术的元素检测装置包括质量分析单元和检测器；还包括：离子源采用磁控管电子回旋共振离子源,从离子源出射离子依次进入第一离子透镜组、第二离子透镜组和质量分析单元；穿过第一离子透镜组的离子被聚焦；穿过第二离子透镜组的离子的动能与所述质量分析单元匹配。本发明具有结构简单、灵敏度高等优点。(The invention provides an element detection device and method based on a mass spectrometry technology, wherein the element detection device based on the mass spectrometry technology comprises a mass analysis unit and a detector; further comprising: the ion source adopts a magnetron electron cyclotron resonance ion source, and ions emitted from the ion source sequentially enter the first ion lens group, the second ion lens group and the mass analysis unit; ions passing through the first ion lens group are focused; the kinetic energy of the ions passing through the second ion lens group is matched with the mass analysis unit. The invention has the advantages of simple structure, high sensitivity and the like.)

1. An element detection apparatus based on mass spectrometry technology, the element detection apparatus based on mass spectrometry technology comprising a mass analysis unit and a detector; characterized in that, the element detection device based on mass spectrum technique still includes:

the ion source adopts a magnetron electron cyclotron resonance ion source, and ions emitted from the ion source sequentially enter the first ion lens group, the second ion lens group and the mass analysis unit;

a first ion lens group through which ions passing through the first ion lens group are focused;

a second ion lens group through which kinetic energy of ions passing through the second ion lens group is matched with the mass analysis unit.

2. The mass spectrometry-based element detection apparatus of claim 1, wherein the second ion lens group comprises a plurality of ion lenses, voltages applied to the plurality of ion lenses in sequence are alternately positive and negative, and kinetic energy of ions passing through the second ion lens group is reduced by two orders of magnitude.

3. The mass spectrometry-based element detection apparatus of claim 1, further comprising:

and the third ion lens group, the ion passes through the second ion lens group and the third ion lens group in turn, and the ion passing through the third ion lens group is deflected.

4. The mass spectrometry-based element detection device of claim 1, wherein the mass analysis unit comprises a first stage multipole mass analyzer, a collision reaction cell and a second stage multipole mass analyzer arranged in sequence.

5. The mass spectrometry-based element detection device of claim 1, wherein the mass analysis unit comprises a repeller, a field-free flight zone comprising a first entrance grid, and a detector; the mass analysis unit further includes:

a first ion acceleration region is formed between the traction electrode and the first incident grid;

the device comprises a first grid and a second grid, wherein the potential difference between the first grid and the second grid is zero; a second ion acceleration area is formed between the repulsion electrode and the first grid, and between the second grid and the traction electrode; the ions sequentially pass through the first grid mesh, the second grid mesh, the first incidence grid mesh and the field-free flight area and are received by the detector.

6. The mass spectrometry-based element detection apparatus of claim 5, wherein the mass analysis unit further comprises:

a reflective region including a first reflective field including a second incident grid and reflective electrodes and a second reflective field including the reflective electrodes and reflective plates; ions emerging from the field-free flight zone are reflected by the reflective zone and are then received by the detector.

7. The mass spectrometry-based element detection apparatus of claim 6, wherein the second ion acceleration region and the first and second reflected fields satisfy:

E₁、E₃、E₄、E₅electric field intensity, z, of the second ion acceleration region, the first reflection field and the second reflection field, respectively₀、d_G、d₂、d₃、d₄、d₅The distance between the incident ions and the first grid, the distance between the first grid and the second grid, the distance between the second grid and the traction electrode, the distance between the traction electrode and the first incident grid, the distance between the second incident grid and the reflection electrode, and the distance between the reflection electrode and the reflection plate are respectively; l is the length of flight of the ions between the first entrance grid and the detector.

8. The mass spectrometry-based element detection apparatus of claim 5, wherein the second ion acceleration region and the field-free reflection region satisfy:

E₁、E₃electric field intensity, z, of the second ion acceleration region and the first ion acceleration region, respectively₀、d_G、d₂、d₃Respectively the distance between the incident ion and the first grid, the distance between the first grid and the second grid, the distance between the second grid and the traction electrode, and the distance between the traction electrode and the first incident grid; l is the length of flight of the ions between the first entrance grid and the detector.

9. The element detection method based on the mass spectrometry technology comprises the following steps:

(A1) the object to be measured is ionized in the magnetron electron cyclotron resonance ion source;

(A2) ions are sequentially focused and kinetic energy is reduced, and the kinetic energy of the ions is matched with the mass analysis unit;

(A3) the detector receives the ions emitted from the mass analysis unit, thereby obtaining the content of the element in the object to be measured.

10. The method for mass spectrometry-based element detection of claim 9, wherein in step (a2), the ion kinetic energy is reduced by two orders of magnitude.

Technical Field

The invention relates to mass spectrometry, in particular to an element detection device and method based on mass spectrometry technology.

Background

At present, the ICP-MS technique is a common analysis technique, and the specific mode is: the high-temperature ionization characteristic of ICP is combined with the advantage of sensitive and rapid scanning of a quadrupole mass spectrometer by a unique interface technology to form a novel element and isotope analysis technology, ICP-MS can measure almost all samples, and multi-element simultaneous determination is completed by one-time collection, so that the primary position of ICP-MS in the trace metal detection technology is established.

In recent years, the industries such as life sciences, alloys, semiconductors and the like have become hot topics, the requirements on the sensitivity and detection limit of mass spectrum detection instruments are increasing day by day, and the original ICP-MS mass spectrum instrument faces challenges. For example, in the semiconductor industry, K, Ca and Fe concentrations in high purity materials are required to be as low as ppt level, but these elements are difficult to measure by ICP-MS due to interference of argon compounds; in the field of life science, a complex matrix sample is often encountered, and cone mouth deposition often occurs to cause signal drift; in alloy detection, such as high-purity manganese dioxide, Cu alloy and the like, as long as a sample enters, the sensitivity is almost remained, and trace metal impurities in the sample cannot be detected at all. In order to solve the above problems, the following methods are generally employed:

1. k, Ca and Fe are detected in a cold plasma mode, so that the interference of Ar-based ions is reduced, and the technical problems brought by the interference are as follows:

the cold mode has its limitations, cannot avoid the interference of water cluster ions to elements, and has the disadvantages of difficult temperature control, large tuning difficulty and poor reproducibility.

2. The interference correction equation is adopted, but the following technical problems are:

the problems are not solved fundamentally, the deposition of the cone mouth still exists, and the maintenance frequency is high. The difference of the matrixes easily causes the failure of the interference correction equation, and an application scheme developer needs to continuously modify the interference correction equation.

3. The sample feeding amount is reduced, and the sample is diluted on line, but the technical problems brought by the dilution are as follows:

there is essentially no major optimization; sometimes, the dilution is thousands of times to maintain sensitivity, and several ppb elements cannot be detected.

Disclosure of Invention

In order to overcome the defects in the prior art, the invention provides an element detection device based on a mass spectrum technology.

The purpose of the invention is realized by the following technical scheme:

an element detection apparatus based on mass spectrometry technology, the element detection apparatus based on mass spectrometry technology comprising a mass analysis unit and a detector; the element detection device based on the mass spectrometry technology further comprises:

the ion source adopts a magnetron electron cyclotron resonance ion source, and ions emitted from the ion source sequentially enter the first ion lens group, the second ion lens group and the mass analysis unit;

a first ion lens group through which ions passing through the first ion lens group are focused;

a second ion lens group through which kinetic energy of ions passing through the second ion lens group is matched with the mass analysis unit.

The invention also provides an element detection method based on the mass spectrometry technology, and the purpose of the invention is realized by the following technical scheme:

the element detection method based on the mass spectrometry technology comprises the following steps:

(A1) the object to be measured is ionized in the magnetron electron cyclotron resonance ion source;

(A2) ions are sequentially focused and kinetic energy is reduced, and the kinetic energy of the ions is matched with the mass analysis unit;

(A3) the detector receives the ions emitted from the mass analysis unit, thereby obtaining the content of the element in the object to be measured.

Compared with the prior art, the invention has the beneficial effects that:

the invention solves the difficulty of combining the magnetron electron cyclotron resonance ion source and the mass spectrum technology, so that the magnetron electron cyclotron resonance ion source and the mass spectrum technology can be combined together to be used as a whole, and a plurality of technical advantages are obtained, such as;

1. the sensitivity is high, and ppt-level trace element detection is realized;

the characteristics of the magnetron electron cyclotron resonance ion source are exerted, the current intensity is high, the beam quality is good, the sensitivity is greatly improved, the detection limit is optimized, complicated mass spectrum correction calculation is not needed, and trace elements can be accurately quantified;

2. the structure is simple, the operation is stable, and the service life is long;

by utilizing the characteristics of the magnetron electron cyclotron resonance ion source, the whole detection device has simple structure, stable operation and long service life;

for a complex matrix, the signal drift phenomenon caused by non-mass spectrum interference does not need to be worried about, and an ion optical system does not need to be maintained;

3. the problem of a bottleneck of adopting a low-resolution mass spectrometer in the industries of life science, alloy, semiconductor and the like is solved, and the advantage of rapid scanning of the low-resolution mass spectrometer is reserved;

4. the resolution is high;

the mass analysis unit can realize second-order time focusing on wider ion initial position dispersion, and the mass resolution is obviously improved;

5. the technical requirement on high-voltage pulse can be reduced by adopting a double-pulse repulsion technology; the invention adopts a double-repulsion mode of positive pulse pushing (repulsion electrode) and negative pulse pulling (traction electrode), the requirement of high voltage can be reduced by half, so that the rising edge is steeper and the pulse waveform can be improved;

the first grid and the second grid with equal electric potential are added in the middle of the double-pulse repulsion, so that the electric field permeation effect of the acceleration region on the ion modulation region can be reduced;

the first grid mesh and the second grid mesh are directly grounded, no extra voltage is added, and the adjusting difficulty is small;

the wide modulation region can be realized, and the ion flux and the sensitivity are improved.

Drawings

The disclosure of the present invention will become more readily understood with reference to the accompanying drawings. As is readily understood by those skilled in the art: these drawings are only for illustrating the technical solutions of the present invention and are not intended to limit the scope of the present invention. In the figure:

FIG. 1 is a schematic diagram of a mass spectrometry based element detection apparatus according to an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a mass analysis unit according to an embodiment of the present invention;

fig. 3 is a diagram of the second order temporal focusing effect of the mass analysis unit according to fig. 2;

FIG. 4 is a schematic structural diagram of a mass analysis unit according to an embodiment of the present invention;

fig. 5 is a diagram of the second order temporal focusing effect of the mass analysis unit according to fig. 4.

Detailed Description

Fig. 1-5 and the following description depict alternative embodiments of the invention to teach those skilled in the art how to make and use the invention. Some conventional aspects have been simplified or omitted for the purpose of explaining the technical solution of the present invention. Those skilled in the art will appreciate that variations or substitutions from these embodiments will be within the scope of the invention. Those skilled in the art will appreciate that the features described below can be combined in various ways to form multiple variations of the invention. Thus, the present invention is not limited to the following alternative embodiments, but is only limited by the claims and their equivalents.

Example 1:

fig. 1 is a schematic structural diagram of an element detection apparatus based on a mass spectrometry technology according to an embodiment of the present invention, and as shown in fig. 1, the element detection apparatus based on a mass spectrometry technology includes:

a mass analysis unit 81 and a detector 91, the mass analysis unit 81 and the detector 91 being prior art in the field;

the ion source 61 is a magnetron electron cyclotron resonance ion source, and ions emitted from the ion source 61 enter the first ion lens group 71, the second ion lens group 72 and the mass analysis unit 81 in sequence;

a first ion lens group 71, ions passing through the first ion lens group 71 being focused;

a second ion lens group 72, kinetic energy of ions passing through the second ion lens group 72 being matched with the mass analysis unit 81.

In order to reduce the kinetic energy of the exiting ions for matching the mass analysis unit 81, further, the second ion lens group 72 includes a plurality of ion lenses, the voltages sequentially applied to the plurality of ion lenses are positive and negative alternately, and the kinetic energy of the ions passing through the second ion lens group 72 is reduced by two orders of magnitude.

In order to remove neutral particles in the ion flow, further, the element detecting device further comprises:

and the third ion lens group, the ion passes through the second ion lens group and the third ion lens group in turn, and the ion passing through the third ion lens group is deflected.

In order to screen ions, the mass analysis unit further comprises a first-stage multipole mass analyzer, a collision reaction cell and a second-stage multipole mass analyzer which are arranged in sequence.

As shown in fig. 2, the mass analysis unit of the embodiment of the present invention includes:

a repeller 11, a field-free flight zone 30 and a detector 51, said field-free flight zone 30 comprising a first entrance grid 31;

a first ion acceleration region is formed between the traction electrode 12 and the first incident grid 31;

a first grid 21 and a second grid 22, wherein the potential difference between the first grid 21 and the second grid 22 is zero; a second ion acceleration region is formed between the repulsion electrode 11 and the first grid 21, and between the second grid 22 and the traction electrode 12; the ions sequentially pass through the first grid 21, the second grid 22, the first incident grid 31 and the field-free flight area 30, and are received by the detector 51;

a plurality of electrodes allowing ions to pass through are arranged between the traction electrode 12 and the first incidence grid 31, and voltage division is carried out on the plurality of electrodes by using a voltage division resistor.

In order to reduce the power requirements, the first grid 21 and the second grid 22 are further grounded.

In order to reduce the requirement on the high voltage of the power supply, further, the element detection device based on the mass spectrometry technology further comprises:

a power supply for applying a positive pulse voltage to the repeller electrode 11 and a negative pulse voltage to the traction electrode 12; alternatively, the power supply applies a negative pulse voltage to the repeller 11 and a positive pulse voltage to the traction electrode 12.

The element detection method based on the mass spectrometry technology comprises the following steps:

(A1) the object to be detected is ionized in the magnetron electron cyclotron resonance ion source, the ion kinetic energy is in kilo electron volt magnitude and is not matched with the existing mass analysis unit;

(A2) ions are sequentially focused and kinetic energy is reduced, the kinetic energy of the ions is matched with a mass analysis unit (the ion kinetic energy needs to be in the order of ten electron volts);

(A3) the detector receives the ions emitted from the mass analysis unit, thereby obtaining the content of the element in the object to be measured.

Example 2:

an application example of the element detection device based on the mass spectrometry technology according to embodiment 1 of the present invention.

In the application example, the first ion lens group comprises three single lenses, and high voltage, negative voltage, low voltage and positive voltage are respectively applied to the three single lenses so that ionized single charge state ions are focused and efficiently transmitted to a subsequent system; the second ion lens group consists of a plurality of ion lenses, the voltages sequentially applied to the ion lenses are in positive and negative alternation, and the kinetic energy of ions passing through the second ion lens group is reduced by two orders of magnitude to dozens of electron volts; the third ion lens group adopts a right-angle deflection lens, so that neutral particles are effectively removed.

As shown in fig. 2, in the mass analysis unit, the first grid 21 and the second grid 22 are grounded, so that the first grid 21 and the second grid 22 are equal in potential; a plurality of electrodes allowing ions to pass through are arranged between the traction electrode 12 and the first incident grid 31, and the voltage of the plurality of electrodes is divided by using a voltage dividing resistor, so that the electric field intensity of the first ion acceleration area is uniform; the power supply applies a positive pulse voltage to the repeller 11 and a negative pulse voltage to the trailing electrode 12.

In order to realize second-order focusing, the second ion acceleration area and the field-free reflection area satisfy the following conditions:

E₁、E₃electric field intensity, z, of the second ion acceleration region and the first ion acceleration region, respectively₀、d_G、d₂、d₃The distance between the incident ion and the first grid 21, the distance between the first grid 21 and the second grid 22, the distance between the second grid 22 and the traction electrode 12, and the distance between the traction electrode 12 and the first incident grid 31; l is the length of flight of the ions in the field-free region between the first entrance grid 31 and the detector 51.

Taking an ion with a mass-to-charge ratio of 100amu as an example, the second-order time focusing effect is shown in fig. 3, and the specific parameters and resolution are shown in the following table:

the element detection method based on the mass spectrometry technology of the embodiment of the invention, namely the working method of the element detection device of the embodiment, comprises the following steps:

(A1) the object to be detected is ionized in the magnetron electron cyclotron resonance ion source, the ion kinetic energy is in kilo electron volt magnitude and is not matched with the existing mass analysis unit;

(A2) ions are sequentially focused and kinetic energy is reduced, the kinetic energy of the ions is matched with a mass analysis unit (the ion kinetic energy needs to be in the order of ten electron volts);

(A3) the detector receives the ions emitted from the mass analysis unit, thereby obtaining the content of the element in the object to be measured.

Example 3:

the application example of the element detection device based on the mass spectrometry technology according to embodiment 1 of the present invention is different from embodiment 2 in that:

as shown in fig. 4, in the mass analysis unit, the first grid 21 and the second grid 22 are grounded, so that the first grid 21 and the second grid 22 are equal in potential; a plurality of electrodes allowing ions to pass through are arranged between the traction electrode 12 and the first incident grid 31, and the voltage of the plurality of electrodes is divided by using a voltage dividing resistor, so that the electric field intensity of the first ion acceleration area is uniform; the power supply applies positive pulse voltage to the repulsion electrode 11 and applies negative pulse voltage to the traction electrode 12;

the reflective region includes a first reflected field including the second incident grid 32 and the reflective electrode 41, and a second reflected field including the reflective electrode 41 and the reflective plate 42; ions exiting the field-free flight zone 30 are reflected by the reflecting zone and then received by the detector 51;

arranging a plurality of electrodes allowing ions to pass through in the first ion acceleration area, the first reflection field and the second reflection field, and dividing the voltage of the plurality of electrodes by using a voltage dividing resistor so that the electric field intensity in the first ion acceleration area, the first reflection field and the second reflection field is uniform;

in order to realize second-order focusing, the second ion acceleration region and the first and second reflection fields satisfy the following conditions:

E₁、E₃、E₄、E₅electric field intensity, z, of the second ion acceleration region, the first reflection field and the second reflection field, respectively₀、d_G、d₂、d₃、d₄、d₅The distance between the incident ion and the first grid 21, the distance between the first grid 21 and the second grid 22, the distance between the second grid 22 and the traction electrode 12, the distance between the traction electrode 12 and the first incident grid 31, the distance between the second incident grid 32 and the reflective electrode 41, and the distance between the reflective electrode 41 and the counter electrode 41, respectivelyThe distance between the shooting plates 42;_Lis the length of flight of the ions in the field-free region between the first entrance grid 31 and the detector 51.

Taking an ion with a mass-to-charge ratio of 100amu as an example, the second-order time focusing effect is shown in fig. 5, and the specific parameters and resolution are shown in the following table:

parameter(s)	Existing design	This patent design
			d1(mm)	50	50
z0(mm)	25	25
			dG(mm)	0	5
d2(mm)	10	10
			d3(mm)	102	102
L＝l1+l2(mm)	1680	1680
			d4(mm)	58	58
E1(V/mm)	20	20
			E3(V/mm)	30	30
E4(V/mm)	-46.6212	-53.0416
			E5(V/mm)	-19.9160	-21.7276
Δz(mm)	4	4
			m/z	100	100
Tof(μs)	29.779	28.8359
			Resolution	95986	1271962

Example 4:

the application example of the element detection device based on the mass spectrometry technology according to embodiment 1 of the present invention is different from embodiment 2 in that:

the mass analysis unit comprises a first-stage multipole rod mass analyzer, a collision reaction tank and a second-stage multipole rod mass analyzer which are sequentially arranged.