Ion source adjusting and measuring device and method

Abstract

The invention relates to an ion source adjusting and testing device and method.The ion source adjusting and testing device comprises an analyzer inlet simulation electrode, a deceleration suppression grid mesh, an ion collector and a mounting flange, and the analyzer inlet simulation electrode is fixed to the mounting flange in a suspended mode and used for replacing an ion analyzer; the deceleration suppression grid mesh is located in front of the ion collector and is used for suppressing secondary electron emission of the ion collector; the ion collector is used for receiving ion flow. According to the ion source adjusting and testing device and method provided by the invention, ions led out from the ion source are modulated, and the ion deceleration voltage is sequentially increased to obtain the sensitivity of the ion source and the energy distribution of the led-out ions; an ion analyzer is removed, the ion source extraction ion state is directly adjusted and measured, the complexity of direct joint debugging of a mass spectrometer is simplified, the adjusting and measuring time is shortened, and a problem source can be rapidly positioned; the method can be used for adjusting and testing various ion sources.

Description

Technical Field

[0001] The present invention relates to the field of mass spectrometry, and more specifically, to an ion source adjustment and testing device. Background Art

[0002] The ion source is one of the core components of a mass spectrometer. It is used to ionize the gas molecules to be measured into ions of various mass-to-charge ratios, accelerate and focus the generated ions through an ion optical lens, and then send them into the analyzer.

[0003] The performance of the ion source largely determines the sensitivity and resolution of the entire mass spectrometer. A good ion source should have the advantages of high ion yield, stable ion yield, high ion utilization, small ion energy dispersion, small ion beam divergence, and high sample utilization. In order to obtain an ion source with excellent performance, structural optimization and electrical parameter debugging are required, which will bring a lot of ion source debugging work. Connecting the ion source to the mass spectrometer system for debugging, on the one hand, greatly increases the complexity of the debugging work, and on the other hand, it will also bring about the problems of long debugging time and difficult fault location. Therefore, an ion source debugging device is designed, which can directly debug the ion source. Summary of the invention

[0004] The embodiments of the present application provide an ion source adjustment device. In order to have a basic understanding of some aspects of the disclosed embodiments, a simple summary is given below. This summary is not a general review, nor is it intended to identify key / important components or describe the scope of protection of these embodiments. Its only purpose is to present some concepts in a simple form as a preface to the detailed description that follows.

[0005] In a first aspect, an embodiment of the present application provides an ion source adjustment and testing device, the device comprising: an analyzer inlet simulation electrode, a deceleration suppression grid, an ion collector and a mounting flange, wherein:

[0006] The analyzer inlet simulation electrode is fixed on the mounting flange and is used to replace the ion analyzer;

[0007] The deceleration suppression grid is located in front of the ion collector, and the deceleration suppression grid is fixed on the mounting flange, and is used to suppress the secondary electron emission of the ion collector;

[0008] The ion collector is fixed on the mounting flange and is used for receiving ion flow.

[0009] According to a preferred embodiment, the voltage of the simulated electrode at the analyzer inlet is adjustable to achieve step-by-step deceleration of ions.

[0010] According to a preferred embodiment, the deceleration suppression grid is a mesh structure, and adopts a fine-wire dense grid design, which is used to balance the contradiction between uniform distribution of the electric field and ion passage rate.

[0011] According to a preferred embodiment, the ion collector is made of a material with low emissivity, such as a molybdenum alloy, to collect ions passing through the simulated electrode at the analyzer inlet.

[0012] According to a preferred embodiment, the mounting flange is modified from a standard flange, and a KF or CF flange can be selected according to the vacuum degree requirement.

[0013] According to a preferred embodiment, the deceleration suppression grid is preferably made of molybdenum alloy material, and stainless steel material may also be used.

[0014] According to another aspect of a preferred embodiment, an embodiment of the present application provides an ion source adjustment device method, the method comprising:

[0015] Step 1, connecting the ion source to the ion source adjustment and testing device, connecting the whole to a vacuum system and evacuating the vacuum system, and when the vacuum system is evacuated to a desired vacuum degree, powering on the ion source to make it work stably;

[0016] Step 2, setting the voltage between the analyzer inlet simulation electrode and the deceleration suppression grid;

[0017] Step 3, introducing a test gas into the ion source, maintaining stability when a desired pressure p is reached, and measuring the ion flow I received by the ion collector using an electrometer;

[0018] Step 4, obtaining the ion source sensitivity S according to the received ion flow I and the gas pressure p and the calculation formula of the ion source sensitivity S=I / p;

[0019] Step 5, gradually increase the voltage of the simulated electrode at the analyzer entrance by 1 to 2 V, measure the corresponding ion flow until the ion flow is 0, and obtain the number of ions with different energies in the ions extracted by the ion source.

[0020] The technical solution provided by the embodiments of the present application may have the following beneficial effects:

[0021] In an embodiment of the present application, an ion source adjustment and testing device includes: an analyzer inlet simulation electrode, a deceleration suppression grid, an ion collector and a mounting flange, wherein: the analyzer inlet simulation electrode is suspended and fixed on the mounting flange to replace the ion analyzer; the deceleration suppression grid is located in front of the ion collector to suppress the secondary electron emission of the ion collector; the ion collector is used to receive ion flow. The ion source adjustment method comprises: step 1, connecting the ion source with the ion source adjustment device, connecting the whole to the vacuum system and evacuating the vacuum system, and when the vacuum is evacuated to the required vacuum degree, powering on the ion source to make it work stably; step 2, setting the voltage of the analyzer inlet simulation electrode and the deceleration suppression grid; step 3, introducing a test gas into the ion source, keeping it stable when the required pressure p is reached, and using an electrometer to measure the ion flow I received by the ion collector; step 4, obtaining the ion source sensitivity S according to the received ion flow I and the gas pressure p and the calculation formula S=I / p of the ion source sensitivity; step 5, gradually increasing the voltage of the analyzer inlet simulation electrode in steps of 1 to 2V, measuring the corresponding ion flow size until the ion flow is 0, and obtaining the number of ions with different energies in the ions extracted by the ion source. The present application describes an ion source adjustment and testing device and method, which modulates the ions extracted from the ion source and increases the ion deceleration voltage in sequence to obtain the sensitivity of the ion source and the energy distribution of the extracted ions; by removing the ion analyzer, the state of the ions extracted from the ion source is directly adjusted, which simplifies the complexity of direct adjustment of the mass spectrometer, shortens the adjustment time and can quickly locate the source of the problem; by adjusting the ion deceleration voltage, the energy distribution of the ions can be measured.

[0022] It is to be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0024] Figure 1 It is a schematic diagram of the principle of an ion source adjustment and testing device provided in an embodiment of the present application;

[0025] Figure 2 It is a flow chart of an ion source adjustment method provided in an embodiment of the present application.

[0026] Figure numerals: 1 - analyzer inlet simulation electrode; 2 - deceleration suppression grid; 3 - ion collector; 4 - mounting flange. DETAILED DESCRIPTION

[0027] The following description and the drawings sufficiently illustrate specific embodiments of the invention to enable those skilled in the art to practice them.

[0028] It should be clear that the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0029] When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples of systems and methods consistent with some aspects of the present invention as detailed in the attached claims.

[0030] In the description of the present invention, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances. In addition, in the description of the present invention, unless otherwise specified, "plurality" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. The character " / " generally indicates that the previously associated objects are in an "or" relationship.

[0031] The following will be combined with the attached Figure 1 -Attached Figure 2 , an ion source adjustment and testing device and method provided in an embodiment of the present application are introduced in detail.

[0032] The present application can directly adjust and test the ion source, and its characteristics are as follows: (1) the ion analyzer is removed, and the state of ions extracted by the ion source is directly adjusted, which simplifies the complexity of direct adjustment of the mass spectrometer, shortens the adjustment time and can quickly locate the source of the problem; (2) by adjusting the ion deceleration voltage, the energy distribution of the ions can be measured.

[0033] See also Figure 1 , which is a schematic diagram of the principle of an ion source adjustment and testing device provided in the embodiment of the present application. Figure 1 As shown, an ion source adjustment and testing device described in an embodiment of the present application may include: an analyzer inlet simulation electrode (1), a deceleration suppression grid (2), an ion collector (3) and a mounting flange (4), wherein:

[0034] The analyzer inlet simulation electrode (1) is fixed on the mounting flange (4) and is used to replace the ion analyzer;

[0035] The deceleration suppression grid (2) is located in front of the ion collector (3), and the deceleration suppression grid (2) is fixed on the mounting flange (4) and is used to suppress the secondary electron emission of the ion collector (3);

[0036] The ion collector (3) is fixed on the mounting flange (4) and is used for receiving the ion flow.

[0037] Specifically, in the embodiment of the present application, the analyzer entrance simulation electrode (1), the deceleration suppression grid (2), and the ion collector (3) are all fixed to the mounting flange (4) in an insulating manner to achieve separate power supply or ion collection; the analyzer entrance simulation electrode (1) is fixed to the mounting flange (4) through a terminal post to ensure that the analyzer entrance simulation electrode (1) is insulated from other electrodes and structures; the analyzer entrance simulation electrode (1) is used to replace the ion analyzer, and the structure and material of the analyzer entrance simulation electrode (1) can be designed according to the simulation object to be consistent with the state of ions entering the ion analyzer as much as possible, and the voltage of the analyzer entrance simulation electrode (1) is adjustable, and the step-by-step deceleration of ions is achieved by adjusting the voltage of the analyzer entrance simulation electrode (1); the deceleration suppression grid (2) is fixed to the mounting flange (4) through a terminal post, and the deceleration suppression grid (2) is preferably First, a low-emissivity material, such as molybdenum alloy, is selected. If cost reduction is required, stainless steel can also be used for conventional testing. For the electrode sheet, when a single window design is adopted, the electric field should be evenly distributed, and the electrode window should be as small as possible, but the ion pass rate will be reduced. Increasing the electrode window will increase the ion pass rate, but the electric field distortion will be larger. The fine-wire dense grid design will make the ion pass window area account for a large proportion while the electric field distortion is small. Therefore, the deceleration suppression grid (2) adopts a fine-wire dense grid design to balance the contradiction between the uniform distribution of the electric field and the ion pass rate. The ion collector (3) adopts a low-emissivity material, such as molybdenum alloy, to collect ions passing through the analyzer inlet simulation electrode (1). The mounting flange (4) adopts a standard flange modification. KF or CF flange can be selected according to the vacuum requirement, and the mounting flange (4) should have at least three terminals to realize electrode power-on and ion flow measurement.

[0038] See also Figure 2 A schematic diagram of a flow chart of an ion source adjustment method is provided for an embodiment of the present application. Figure 2 As shown, the method of the embodiment of the present application may include the following steps:

[0039] Step 1, connect the ion source to the ion source adjustment and testing device, connect the whole to the vacuum system and evacuate the vacuum system. When the vacuum is evacuated to the required vacuum degree, power on the ion source to make it work stably;

[0040] Step 2, setting the voltage between the simulated electrode (1) at the analyzer inlet and the deceleration suppression grid (2), includes:

[0041] The voltage of the simulated electrode (1) at the analyzer inlet is set to the voltage of the simulated object (generally 0V);

[0042] The voltage of the deceleration suppression grid (2) is set to -100V, which can reflect all secondary electrons emitted by the ion collector (3).

[0043] Step 3, introducing a test gas into the ion source, maintaining stability when the required pressure p is reached, and using an electrometer to measure the ion flow I received by the ion collector. In addition, in the embodiment of the present application, the introduced test gas is nitrogen;

[0044] Step 4, obtaining the ion source sensitivity S according to the received ion flow I and gas pressure p and the calculation formula of the ion source sensitivity S=I / p;

[0045] Step 5, gradually increase the voltage of the simulated electrode (1) at the analyzer entrance by 1 to 2 V, measure the corresponding ion flow until the ion flow is 0, and obtain the number of ions with different energies in the ions extracted from the ion source.

[0046] The serial numbers of the above-mentioned embodiments of the present application are for description only and do not represent the advantages or disadvantages of the embodiments.

[0047] The above disclosure is only the preferred embodiment of the present application, which certainly cannot be used to limit the scope of rights of the present application. Therefore, equivalent changes made according to the claims of the present application are still within the scope covered by the present application.

Claims

1. An ion source adjustment and testing device, characterized in that: include: Analyzer inlet dummy electrode, deceleration suppression grid, ion collector and mounting flange, where: The analyzer inlet simulation electrode is fixed on the mounting flange and is used to replace the ion analyzer; The deceleration suppression grid is located in front of the ion collector, and the deceleration suppression grid is fixed on the mounting flange, and is used to suppress the secondary electron emission of the ion collector; The ion collector is fixed on the mounting flange and is used for receiving ion flow.

2. The ion source adjustment and testing device according to claim 1, characterized in that: The voltage of the simulated electrode at the analyzer entrance is adjustable to achieve step-by-step deceleration of ions.

3. The ion source adjustment and testing device according to claim 1, characterized in that: The deceleration suppression grid is a mesh structure, and adopts a fine-wire dense grid design, which is used to balance the contradiction between the uniform distribution of the electric field and the ion passing rate.

4. The ion source adjustment and testing device according to claim 1, characterized in that: The ion collector is made of a material with low emissivity, such as a molybdenum alloy, and is used to collect ions passing through the simulated electrode at the analyzer entrance.

5. The ion source adjustment and testing device according to claim 1, characterized in that: The mounting flange is modified from a standard flange, and a KF or CF flange can be selected according to vacuum requirements.

6. The ion source adjustment and testing device according to claim 3, characterized in that: The deceleration suppression grid is preferably made of molybdenum alloy material, but can also be made of stainless steel.

7. An ion source adjustment method, characterized in that: An ion source adjustment and testing device according to claims 1-6, comprising: Step 1, connecting the ion source to the ion source adjustment and testing device, connecting the whole to a vacuum system and evacuating the vacuum system, and when the vacuum system is evacuated to a desired vacuum degree, powering on the ion source to make it work stably; Step 2, setting the voltage between the analyzer inlet simulation electrode and the deceleration suppression grid; Step 3, introducing a test gas into the ion source, maintaining stability when a desired pressure p is reached, and measuring the ion flow I received by the ion collector using an electrometer; Step 4, obtaining the ion source sensitivity S according to the received ion flow I and the gas pressure p and the calculation formula of the ion source sensitivity S=I / p; Step 5, gradually increase the voltage of the simulated electrode at the analyzer entrance in steps of 2V, measure the corresponding ion flow, until the ion flow is 0, and obtain the number of ions with different energies in the ions extracted by the ion source.

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