A Laser Sputtering Ion Source Device with an Embedded Lens and a Mass Spectrometer

Abstract

The present invention discloses a laser sputtering ion source device with an internal lens and a mass spectrometer, belonging to the technical field of mass spectrometry analysis instruments. It includes a pulsed gas inlet valve and a laser incident channel. The bottom of the pulsed gas inlet valve is connected to a skimmer support. An ion growth throat is provided inside the skimmer support. A sealing lens is provided at the front end of the laser incident channel, and the end of the laser incident channel is connected to a sample target stage. By adopting the above-mentioned laser sputtering ion source device with an internal lens and a mass spectrometer, the present invention can effectively grow high-quality cluster ions, meet the experimental requirements of high quality, and has better experimental performance.

Description

Technical Field

[0001] The present invention relates to the technical field of mass spectrometry instruments, and in particular, to a laser ablation ion source device with an internal lens and a mass spectrometer. Background Art

[0002] For decades, techniques that combine mass spectrometry with spectroscopic analysis, such as photoelectron spectroscopy and infrared photodissociation spectroscopy, have become common means in the field of gas-phase ion cluster research. The rapid development of time-of-flight mass spectrometry has led to great applications of infrared photodissociation spectroscopy based on time-of-flight mass spectrometry, providing a good technical means for studying molecular dynamics. As a key component of a mass spectrometry instrument, the selection and structural design of the ion source directly affect the generation of the target research system, which is the prerequisite for subsequent experiments and the guarantee of experimental quality.

[0003] After decades of development, laser ablation ion source technology has been widely used in metal ion-molecule cluster mass spectrometry and spectroscopic research and analysis, becoming an important and unique ion source option. Its basic function can be briefly described as follows: When the ablation laser hits the metal sample target, it will ablate, evaporate, and gasify it, generating a high-temperature and high-density plasma. Subsequently, in the growth throat, it collides with the carrier gas ejected from the pulsed inlet valve to form complexes and cluster ions, which then freely expand into an ultrasonic ion beam. Then, after being intercepted by the ion skimmer downstream of the throat, they are introduced into the extraction field of the time-of-flight mass analyzer.

[0004] The generation of cluster ions is related to factors such as the energy of the ablation laser, the front-end gas pressure and pulse width of the pulse valve, the photo-gas delay, the growth throat, and the surface properties of the sample. For example, the so-called "standard source" that is currently widely used introduces the ablation laser through an optical inlet open to the vacuum chamber to act on the sample target. The metal plasma generated by laser ablation sputtering may rapidly diffuse outward, resulting in an impact on the generation of ion clusters after the carrier gas is ejected from the pulsed inlet valve. Summary of the Invention

[0005] The object of the present invention is to provide a laser ablation ion source device with an internal lens and a mass spectrometer, which can effectively grow high-quality cluster ions, meet the requirements of high-quality experiments, and have better experimental performance.

[0006] To achieve the above object, the present invention provides a laser ablation ion source device with an internal lens, including a pulsed inlet valve and a laser incident channel. The bottom of the pulsed inlet valve is connected to a skimmer bracket, and an ion growth throat is provided inside the skimmer bracket. A sealing lens is provided at the front end of the laser incident channel, and the end of the laser incident channel is connected to a sample target stage.

[0007] The ion growth throat is designed as a four-way aluminum alloy block, and the first through-hole and the second through-hole with different diameters are respectively opened on the x-axis plane and the y-axis plane.

[0008] Preferably, the first through-hole is connected to the laser incident channel, and the second through-hole is connected to the pulsed gas inlet valve.

[0009] Preferably, an antireflection film matching the laser wavelength is coated on the surface of the sealing lens.

[0010] Preferably, the sample target stage is opposite to the sealing lens.

[0011] Preferably, an argon purge channel is provided on one side of the ion growth throat, and the end of the argon purge channel is perpendicularly connected to the laser incident channel and close to the sealing lens.

[0012] Preferably, the skimmer bracket is made of stainless steel, and a skimmer sampler is provided on the skimmer bracket.

[0013] Preferably, an installation hole is provided on the side of the sample target stage far from the sealing lens. The sample target stage is connected to the target rod through the installation hole, and the other side of the target rod is connected to a stepper motor on the sample target stage.

[0014] The present invention also provides a mass spectrometer, including the laser sputtering ion source device with an internal lens mentioned above.

[0015] Therefore, by adopting the above laser sputtering ion source device with an internal lens and the mass spectrometer, the present invention can effectively grow high-quality cluster ions, meet the high-quality experimental requirements, and have better experimental performance. One is to provide a laser sputtering ion source device, which is suitable for the generation of metal ion clusters; the other is to provide a mass spectrometry-infrared spectroscopy combined instrument including the above laser sputtering ion source with an internal lens.

[0016] Next, through the drawings and embodiments, the technical solutions of the present invention will be further described in detail. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a cross-sectional view of an embodiment of a laser sputtering ion source device with an internal lens according to the present invention;

[0018] Figure 2 is a schematic structural diagram of an ion growth throat of an embodiment of a laser sputtering ion source device with an internal lens according to the present invention;

[0019] Figure 3 is a schematic structural diagram of a skimmer bracket of an embodiment of a laser sputtering ion source device with an internal lens according to the present invention;

[0020] Figure 4 This is a schematic structural diagram of the sample target stage provided by an embodiment of a laser sputtering ion source device with a built-in lens according to the present invention.

[0021] Reference numerals

[0022] 1. Ion growth throat; 2. Sealing lens; 3. Sample target stage; 4. Argon purge channel; 5. Target rod; 6. Pulse inlet valve; 7. Skimmer bracket; 8. Laser incident channel; 9. First through hole; 10. Mounting hole; 11. Second through hole. Detailed implementation manners

[0023] The technical solutions of the present invention will be further described below with reference to the drawings and embodiments.

[0024] Unless otherwise defined, the technical terms or scientific terms used in the present invention shall have the ordinary meanings understood by those of ordinary skill in the field to which the present invention belongs. The "first", "second" and similar terms used in the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "including" or "comprising" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0025] Embodiment 1

[0026] As Figure 1 shown, the present invention provides a laser sputtering ion source device with a built-in lens, which is mainly used for the growth and guidance of metal ion-molecular clusters. It includes a pulse inlet valve 6 and a laser incident channel 8. The bottom of the pulse inlet valve 6 is connected to a skimmer bracket 7. As Figure 3 shown, the rear end of the skimmer bracket 7 supports and connects a skimmer sampler, and an ion growth throat 1 is provided inside the skimmer bracket 7.

[0027] As Figure 2 shown, the ion growth throat 1 is designed as a four-way aluminum alloy block, and the first through hole 9 and the second through hole 11 with different diameters are respectively opened on the x-axis plane and the y-axis plane. The first through hole 9 is connected to the laser incident channel 8, and the second through hole 11 is connected to the pulse inlet valve 6.

[0028] At the front end of the laser incident channel 8, there is a sealing lens 2, and an antireflection film matching the laser wavelength is coated on the surface of the sealing lens 2. The sealing lens 2 can be made of fused quartz or sapphire material, and is fixed to the front end of the laser incident channel 8 through a stainless steel quick-release bracket flange and a copper sealing ring. The end of the laser incident channel 8 is connected to the sample target stage 3. The sample target stage 3 is opposite to the sealing lens 2 and is connected to the ion growth throat 1.

[0029] When applying the laser sputtering ion source device with an internal lens provided by the above embodiment, since the light inlet in the ion formation and growth region is hermetically sealed by a lens, it is isolated from the external cavity before entering the time-of-flight mass analyzer through the skimmer sampler. In this way, the sealed light inlet direction will reduce the outward diffusion and leakage of metal plasma, which is more conducive to its collision with the gas introduced by the pulse valve and the downward guidance of the ion cluster, so as to effectively grow high-quality cluster ions.

[0030] The laser sputtering ion source device further includes an argon purge channel 4, a skimmer bracket 7 and a target rod 5. The argon purge channel 4 is perpendicularly connected to the laser incident channel 8 and is close to the sealing lens 2. The skimmer bracket 7 is made of stainless steel. The front end of the skimmer bracket 7 is fixed to the ion growth throat 1 and the pulse inlet valve 6 on the same nozzle bracket. The rear end of the skimmer bracket 7 supports and connects the skimmer sampler. As Figure 4 shown, on the side of the sample target stage 3 far from the sealing lens 2, there is an installation hole 10. The sample target stage 3 is connected to the target rod 5 through the installation hole 10, and the other side of the target rod 5 is connected to a stepping motor to the sample target stage 3.

[0031] Specifically, the argon purge channel 4 and the laser incident channel 8 form a tee structure, and the external port of the argon purge channel 4 is connected to the purge inlet valve through a threaded part. The sample target stage 3 is driven by the stepping motor through the target rod 5 to make a circular precession up and down, greatly improving the efficiency of laser sputtering the sample. Blowing air inward through the argon purge channel 4 can prevent the plasma from cooling and condensing on the inner surface of the lens after the ion source works for a long time, affecting the subsequent light inlet efficiency. At the same time, this design also helps the cooling gas such as argon to be used as possible attachment molecules, improving the rare-gas-tagging efficiency and preparing for the subsequent single-photon infrared photodissociation experiment.

[0032] The present invention also provides a mass spectrometer, including the laser sputtering ion source device mentioned above. Since the above laser sputtering ion source device has the above technical effects, the mass spectrometer with this laser sputtering ion source should also have corresponding technical effects.

[0033] Therefore, by adopting the above laser sputtering ion source device with an internal lens and the mass spectrometer, the present invention can effectively grow high-quality cluster ions, meet the experimental requirements of high quality, and have better experimental performance.

[0034] It should be noted that the content not elaborated in detail in the present invention is all prior art and is well known to those skilled in the art.

[0035] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present invention, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. A laser sputtering ion source device with a built-in lens, comprising a pulsed air inlet valve and a laser incident channel, characterized in that: The bottom of the pulse intake valve is connected to a skimmer bracket, an ion growth throat is arranged inside the skimmer bracket, a sealing lens is arranged at the front end of the laser incident channel, and the end of the laser incident channel is connected to a sample target stand; the ion growth throat is designed as a four-way aluminum alloy square, and a first through hole and a second through hole of different diameters are respectively opened on its x-axis surface and y-axis surface.

2. The laser sputtering ion source device with a built-in lens according to claim 1, characterized in that: The first through hole is connected to the laser incident channel, and the second through hole is connected to the pulse intake valve.

3. The laser sputtering ion source device with a built-in lens according to claim 1, characterized in that: The surface of the sealing lens is coated with an anti-reflection film matching the laser wavelength.

4. The laser sputtering ion source device with a built-in lens according to claim 1, characterized in that: The sample target stage is opposite to the sealing lens.

5. The laser sputtering ion source device with built-in lens according to claim 1, characterized in that: An argon purge channel is provided on one side of the ion growth throat, and the end of the argon purge channel is vertically connected to the laser incident channel and is close to the sealing lens.

6. The laser sputtering ion source device with built-in lens according to claim 1, characterized in that: The skimmer bracket is made of stainless steel.

7. The laser sputtering ion source device with built-in lens according to claim 1, characterized in that: A mounting hole is provided on a side of the sample target material stand away from the sealing lens, and the sample target material stand is connected to the target material connecting rod through the mounting hole.

8. A mass spectrometer, characterized in that: A laser sputtering ion source device comprising a built-in lens as described in any one of claims 1 to 7.

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