A sample observation device in a secondary ion mass spectrometer

Abstract

The present invention relates to a sample observation device in a secondary ion mass spectrometer. The sample observation device described in the present invention includes a disc, and the disc is provided with an observation hole, a light incident hole, a through hole, and a shielding mechanism. A light guide column is arranged in the observation hole; the light incident hole and the observation hole respectively penetrate through the disc. The light incident hole forms a first light guide path penetrating through the disc, and the observation hole forms a second light guide path penetrating through the disc. A part of the first light guide path and the second light guide path extending below the disc forms an intersection area, and this intersection area is used to place a sample; the shielding mechanism includes an operation part, a connection part, and a shielding part connected in sequence. The operation part can be operably passed through the connection part and drive the shielding part to shield or expose the observation hole. The sample observation device described in the present invention has a simple structure and can effectively observe the sample and the escape situation of secondary ions on the sample surface.

Description

Technical Field

[0001] The present invention relates to the technical field of secondary ion mass spectrometers, and particularly to a sample observation device in a secondary ion mass spectrometer. Background Art

[0002] Secondary Ion Mass Spectroscopy (SIMS) is one of the most widely used techniques in surface analysis. It has high sensitivity (the lowest detectable concentration can reach the ppm or even ppb order of magnitude), high resolution (about 10 -9 ) and low detection limit (absolute detection limit of 10 -13 -10 -19 grams), can be used to detect the isotope abundance ratios of all elements including hydrogen, can analyze the components and molecular structures of unknown analytical compounds in a sample, can obtain information on the surface layer of the sample, can perform line scan analysis, can generate three-dimensional images of ion distributions, and can also perform micro-area imaging and depth profile analysis of specific elements.

[0003] Because the secondary ion mass spectrometer has extremely high sensitivity, it is particularly suitable for quantitative analysis of micro-area doping, elements and their isotopes, impurity contamination, and material composition. Especially in the semiconductor field, because its process has particularly high requirements for the concentration and purity of doping, during the analysis of the prepared sample using a secondary ion mass spectrometer, in order to clearly observe the sample and the state of secondary ion emission from the sample surface, a new sample observation device needs to be set in the secondary ion mass spectrometer. Summary of the Invention

[0004] Based on this, the object of the present invention is to provide a sample observation device in a secondary ion mass spectrometer, which has a simple structure and can effectively observe the sample and the emission of secondary ions from the sample surface.

[0005] The present invention is realized by the following technical solutions:

[0006] A sample observation device in a secondary ion mass spectrometer is arranged inside the secondary ion mass spectrometer. The device includes a disc, and the disc is provided with an observation hole, a light incident hole, a through hole, and a shielding mechanism. A light guide column is arranged in the observation hole;

[0007] The light incident hole and the observation hole penetrate through the disc respectively. The light incident hole forms a first light guide path penetrating through the disc, and the observation hole forms a second light guide path penetrating through the disc. The part of the first light guide path and the second light guide path extending below the disc forms an intersection area, and this intersection area is used to place the sample;

[0008] The shielding mechanism includes an operation part, a connection part and a shielding part connected in sequence. The operation part is arranged on the upper end surface of the disc, the connection part is arranged in the through hole, the shielding part is arranged on the lower end surface of the disc, and the operation part can operably pass through the connection part and drive the shielding part to shield or expose the observation hole.

[0009] Further, the operation part includes a driving plate, the connection part includes a transmission column, and the shielding part includes a shielding sheet. The driving plate and the shielding sheet are respectively parallel to the end surface of the disc. The driving plate is fixedly connected to the upper end of the transmission column, and the lower end of the transmission column is fixedly connected to the shielding sheet.

[0010] Further, the operation part further includes a pushing column. The pushing column is arranged at one end of the driving plate away from the transmission column, and the pushing column is used to connect a pushing rod extending outside the secondary ion mass spectrometer.

[0011] Further, a groove is further arranged on the upper end surface of the disc. The shielding mechanism further includes an elastic limiting part. The elastic limiting part includes a fixing part, an extending part and a limiting part. The fixing part is fixedly connected to the transmission column. The limiting part is connected to the fixing part through the extending part, and the limiting part is arranged in the groove.

[0012] Further, the extending part includes a bent section and a straight section. The bent section is arc-shaped. One end of the bent section is connected to the fixing part on one side of the transmission column, and the other end of the bent section bypasses the other side of the transmission column and is connected to the limiting part through the straight section.

[0013] Further, the included angles between the first light guiding path and the second light guiding path and the direction perpendicular to the end surface of the disc are 30° to 50°.

[0014] Further, the upper and lower end surfaces of the light guiding column are parallel and the surfaces are smooth, and the side surface is frosted.

[0015] Further, the transmission column includes a metal inner column and a ceramic outer shell, and the elastic limiting part is fixedly connected to the metal inner column.

[0016] Further, an ion incident hole and an electron incident hole are further arranged through the disc.

[0017] Further, the straight line where the ion incident hole and the electron incident hole are located is perpendicular to the straight line where the observation hole and the light incident hole are located.

[0018] A sample observation device in a secondary ion mass spectrometer provided by the present invention conducts light through a light incident hole, an observation hole, and a light guide column in the observation hole, so that light enters from the light incident hole and irradiates the sample. The light reflected from the surface of the sample is conducted through the light guide column and enters the camera outside the observation hole. The present invention separates the sample chamber where the primary ion beam bombards the sample from the camera that collects image data, and at the same time sets up a shielding mechanism to protect the light guide column, which can effectively observe the sample and the escape of secondary ions on the surface of the sample, and protect the camera and the light guide column from being contaminated by primary ions, meeting the unique sample observation requirements in the secondary ion mass spectrometer.

[0019] For better understanding and implementation, the present invention will be described in detail below with reference to the accompanying drawings. Description of the Drawings

[0020] Figure 1 It is a schematic structural diagram of a sample observation device in a secondary ion mass spectrometer in this embodiment;

[0021] Figure 2 It is a schematic structural diagram of a shielding mechanism of a sample observation device in a secondary ion mass spectrometer in this embodiment;

[0022] Figure 3 It is a schematic structural diagram of a disc of a sample observation device in a secondary ion mass spectrometer in this embodiment. Description of the Drawings:

[0024] 1. Disc; 11. Observation hole; 12. Light incident hole; 13. Through hole; 14. Groove; 15. Electron incident hole; 16. Ion incident hole; 2. Shielding mechanism; 21. Driving plate; 22. Transmission column; 23. Shielding sheet; 24. Pushing column; 25. Spring; 3. Light guide column. Detailed Embodiment

[0025] The following are specific embodiments of the present invention and in combination with the accompanying drawings, the technical solutions of the present invention will be further described, but the present invention is not limited to these embodiments.

[0026] In the description of the present invention, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation to the present invention.

[0027] It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there may also be an intermediate element. When an element is considered to be "connected" to another element, it can be directly connected to the other element or there may be an intermediate element at the same time.

[0028] As Figure 1 shown, Figure 1 A sample observation device in a secondary ion mass spectrometer provided by an embodiment of the present invention is shown. This device is used to be arranged inside the secondary ion mass spectrometer and used in a vacuum environment. It can clearly observe the sample and the state of secondary ion emission from the sample surface during the process of using the secondary ion mass spectrometer to analyze the prepared sample. The sample observation device includes a disk 1, which can be a solid metal plate with a thickness of about 5 - 10 mm. The sample to be analyzed is placed below the disk. Among them, the sample to be analyzed can be metal, alloy, semiconductor, insulator, organic matter, biofilm, etc. At the same time, an electron incident hole 15 and an ion incident hole 16 are penetratedly arranged on the disk 1. The electron incident hole 15 and the ion incident hole 16 are set to be both oriented towards the position where the sample is placed for the incidence of the primary ion beam. After the incidence, the primary ion beam bombards the sample surface to cause secondary ions to escape from the sample surface.

[0029] As Figure 1 shown, an observation hole 11 and a light incident hole 12 are also penetratedly arranged on the disk 1 to realize the observation of the sample. Among them, the light incident hole 12 is used to introduce light to the sample to be analyzed below the disk 1, and the observation hole 11 is used to provide an observation channel for the camera arranged on the upper end surface of the disk to observe the sample and the state of secondary ion emission from the sample surface. The user can observe the sample by watching the image collected by the camera through the external display of the secondary ion mass spectrometer.

[0030] Optionally, a light guide column 3 is arranged in the observation hole 11 for conducting the light reflected on the sample surface to the camera. Specifically, the light incident hole 12 forms a first light guide path penetrating the disk 1, and the observation hole 11 forms a second light guide path penetrating the disk. The part of the first light guide path and the second light guide path extending below the disk forms an intersection area, and this intersection area is used to place the sample, so that light energy can enter the sample observation device through the light incident hole 12, irradiate on the sample along the first light guide path, and the light reflected from the sample surface enters the camera through the second light guide path and the light guide column 3 through the observation hole 11.

[0031] Optionally, the diameters of the light incident hole 12 and the observation hole 11 range from 3 to 8 mm, and the angles between the first light guiding path and the second light guiding path and the vertical direction of the end face of the disk 1 are 30° to 50°, that is, the range of the angle between the incident angle of light and the normal of the incident surface is 30° to 50°. Correspondingly, the diameter of the light guiding column 3 is 2 to 4 mm, and is smaller than the diameter of the observation hole 11, and the length is 13 to 17 mm. Preferably, the light guiding column 3 is made of quartz or glass, the upper and lower end faces are parallel and the surface is smooth, and the side surface is frosted.

[0032] Optionally, the straight line where the electron incident hole 15 and the ion incident hole 16 are located is perpendicular to the straight line where the observation hole 11 and the light incident hole 12 are located.

[0033] As Figure 1 shown, a through hole 13 and a shielding mechanism 2 are further provided on the disk 1. The shielding mechanism 2 is installed on the disk 1 through the through hole 13, and the shielding mechanism 2 is used to adjustably shield or expose the observation hole 11. Since the light guiding column is easily contaminated by primary ions during the process of bombarding the sample surface with primary ions, the device can push the shielding mechanism 2 to shield the observation hole 11 during the incidence of primary ions, thereby protecting the light guiding column 3.

[0034] As Figure 2 shown, the shielding mechanism 2 includes an operation part, a connecting part and a shielding part connected in sequence. The operation part is arranged on the upper end face of the disk 1, the connecting part is arranged in the through hole 13, and the shielding part is arranged on the lower end face of the disk 1. The operation part can operably pass through the connecting part and drive the shielding part to shield or expose the observation hole 11, thereby protecting the light guiding column 3 in the observation hole 11 from being contaminated by ions.

[0035] Specifically, the operation part includes a driving plate 21, the connecting part includes a transmission column 22, and the shielding part includes a shielding piece 23. The driving plate 21 and the shielding piece 23 are respectively parallel to the end face of the disk 1. The driving plate 21 is fixedly connected to the upper end of the transmission column 22, and the lower end of the transmission column 22 is fixedly connected to the shielding piece 23. In this preferred embodiment, one end of the driving plate 21 has a circular through hole with a semicircular groove. The upper end of the transmission column 22 includes a bolt. The driving plate 21 and the transmission column 22 are assembled and fixed by screws installed from top to bottom, and the transmission column 22 and the shielding piece 23 are vertically fixed by welding.

[0036] Preferably, the operation part further includes a push column 24, which is arranged above the end of the driving plate 21 away from the transmission column 22. The push column 24 is used to connect a push rod extending to the outside of the secondary ion mass spectrometer, so that pressure can be applied to the push column 24 from outside the vacuum to push the driving plate 21, and drive the shielding piece 23 through the transmission column 22 to shield the observation hole 11. Preferably, the push rod can be a corrugated pipe, which has a cylindrical thin-walled fold with multiple transverse corrugations and is elastic, capable of generating displacement under the action of pressure, axial force, transverse force or bending moment.

[0037] Preferably, the transmission column 22 includes a metal inner column and a ceramic outer shell. The ceramic outer shell is sleeved on the middle and lower sections of the metal inner column. The ceramic outer shell is used to isolate electricity when the sample is connected to a 4500-volt DC high voltage. In this embodiment, the length of the metal inner column ranges from 15 to 35 mm, the diameter ranges from 2 to 5 mm, the length of the ceramic outer shell ranges from 15 to 25 mm, the inner diameter of the ceramic outer shell ranges from 2 to 5 mm, and the outer diameter of the ceramic ring sleeve ranges from 5 to 10 mm.

[0038] Optionally, the shape of the shielding piece 23 is a rectangle with four chamfers. The length of the shielding piece 23 ranges from 25 to 35 mm, the width ranges from 5 to 15 mm, and the thickness ranges from 1 to 3 mm.

[0039] As Figure 2 and 3 shown, a groove 14 is further provided on the upper end surface of the disc 1, and the groove 14 corresponds to the operation part of the shielding mechanism 2 in the shielding state and the non-shielding state. The shielding mechanism 2 further includes an elastic limiting member. In this embodiment, the elastic limiting member is a spring 25. The spring 25 includes a fixing part, an extending part and a limiting part. The fixing part is fixedly connected to the transmission column 22 of the shielding mechanism 2. The limiting part is connected to the fixing part through the extending part, and the limiting part is arranged in the groove 14. Preferably, a circular through hole is provided at one end of the metal inner column of the transmission column 22 close to the transmission plate, and the fixing part of the spring 25 passes through the through hole and is fixed to the transmission column 22. The extending part of the spring 25 includes a bent section and a straight section. The bent section is arc-shaped. One end of the bent section is connected to the fixing part on one side of the transmission column 22, and the other end of the bent section passes around the other side of the transmission column 22 and is connected to the limiting part through the straight section. The limiting part of the spring 25 is arc-shaped, so that when the spring 25 moves in the groove 14, the arc section and the end of the arc can respectively abut against the two side walls of the groove 14.

[0040] When the operating part of the shielding mechanism 2 is driven by an external push rod, the spring 25 can rotate around the transmission column 22 in the groove 14. At the same time, the side wall of the groove 14 can limit the movement of the spring 25, thereby restricting the rotation of the operating part. When it is necessary to observe the sample, no pressure is applied to the push column 24 by the external push rod, and the spring 25 and the transmission column 22 are in a free state, and the observation hole 11 is exposed. When it is not necessary to observe the sample, pressure is applied to the push column 24 through the external push rod, thereby driving the driving plate 21 and the transmission column 22 to rotate, driving the spring 25 to move in the groove 14 until the spring 25 touches the side wall of the groove 14 and stops moving. At this time, the shielding piece 23 fixedly connected to the transmission column 22 is in the limit position, directly below the observation hole 11 on the lower end surface of the disc 1, so that the shielding piece 23 can shield the observation hole 11 and protect the light guide column 3 from being ion contaminated.

[0041] In the process of using the embodiment of the present invention, light energy enters the sample observation device through the light incident hole 12, irradiates on the sample along the first light guide path, and the light reflected from the sample surface passes through the observation hole 11 along the second light guide path and the light guide column 3, so that the camera can collect image information. However, generally when bombarding the sample with a primary ion beam, it is necessary to shield the observation hole 11 to protect the light guide column 3 from being ion contaminated. The user applies pressure to the push column 24 of the shielding mechanism 2 through a push rod connected to the outside of the secondary ion mass spectrometer. The push column 24 drives the driving plate 21 and the transmission column 22 to rotate, and the spring 25 connected to the transmission column 22 moves in the groove 14 accordingly until the spring 25 abuts against the side wall of the groove 14. The movement of the spring 25 is restricted, so that the shielding piece 23 is exactly located directly below the observation hole 11, and can shield the observation hole 11 to protect the light guide column 3 from being ion contaminated. When the bombardment of the sample with the primary ion beam is completed and it is necessary to observe the escape of secondary ions on the sample surface, the push rod outside the vacuum is released, so that the push column 24 and the spring 25 return to the unloaded state, and the observation hole 11 is exposed again. At this time, the light path is no longer blocked, and the user can observe the sample surface through the image information collected by the camera.

[0042] A sample observation device in a secondary ion mass spectrometer provided by the present invention conducts light through the light incident hole, the observation hole and the light guide column in the observation hole, so that light enters through the light incident hole and irradiates the sample, and the light reflected from the sample surface is conducted through the light guide column and enters the camera outside the observation hole. The present invention separates the sample chamber where the primary ion beam bombards the sample and the camera that collects image data, and at the same time sets a shielding mechanism to protect the light guide column, which can effectively observe the sample and the escape of secondary ions on the sample surface, and protect the camera and the light guide column from being contaminated by primary ions, meeting the unique sample observation requirements in the secondary ion mass spectrometer.

[0043] The above-described embodiments merely represent several implementation manners of the present invention. The description thereof is relatively specific and detailed, but it should not be construed as a limitation to the scope of the invention patent. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several modifications and improvements can still be made, and these all fall within the protection scope of the present invention.

Claims

1. A sample observation device in a secondary ion mass spectrometer, which is disposed inside the secondary ion mass spectrometer, and is characterized in that, The device includes: a disc, on which an observation hole, a light incident hole, a through hole and a shielding mechanism are provided, and a light guide column is arranged in the observation hole; the light incident hole and the observation hole penetrate through the disc respectively, the light incident hole forms a first light guide path penetrating through the disc, the observation hole forms a second light guide path penetrating through the disc, and a part of the first light guide path and the second light guide path extending below the disc forms an intersection area for placing a sample; the shielding mechanism includes an operation part, a connecting part and a shielding part which are connected in sequence, the operation part is arranged on the upper end face of the disc, the connecting part is arranged in the through hole, the shielding part is arranged on the lower end face of the disc, and the operation part can be operable to pass through the connecting part and drive the shielding part to shield or expose the observation hole.

2. The sample observation device in a secondary ion mass spectrometer according to claim 1, wherein: the operation part includes a driving plate, the connecting part includes a transmission column, the shielding part includes a shielding sheet, the driving plate and the shielding sheet are respectively parallel to the end face of the disc, the driving plate is fixedly connected to the upper end of the transmission column, and the lower end of the transmission column is fixedly connected to the shielding sheet.

3. The sample observation device in a secondary ion mass spectrometer according to claim 2, wherein: the operation part further includes a pushing column, the pushing column is arranged at one end of the driving plate away from the transmission column, and the pushing column is used for connecting a push rod extending outside the secondary ion mass spectrometer.

4. The sample observation device in a secondary ion mass spectrometer according to claim 2, wherein: a groove is further arranged on the upper end face of the disc, the shielding mechanism further includes an elastic limiting member, the elastic limiting member includes a fixing part, an extending part and a limiting part, the fixing part is fixedly connected to the transmission column, the limiting part is connected to the fixing part through the extending part, and the limiting part is arranged in the groove.

5. The sample observation device in a secondary ion mass spectrometer according to claim 4, wherein: the extending part includes a bent section and a straight section, the bent section is arc-shaped, one end of the bent section is connected to the fixing part on one side of the transmission column, and the other end of the bent section bypasses the other side of the transmission column and is connected to the limiting part through the straight section.

6. The sample observation device in a secondary ion mass spectrometer according to claim 1, wherein: the included angles between the first light guide path and the second light guide path and the direction perpendicular to the end face of the disc are 30° to 50°.

7. The sample observation device in a secondary ion mass spectrometer according to claim 1, wherein: the upper and lower end faces of the light guide column are parallel and the surfaces are smooth, and the side surface is frosted.

8. The sample observation device in a secondary ion mass spectrometer according to claim 4, wherein: the transmission column includes a metal inner column and a ceramic outer shell, and the elastic limiting member is fixedly connected to the metal inner column.

9. The sample observation device in a secondary ion mass spectrometer according to claim 1, characterized in that: An ion incident hole and an electron incident hole are further penetratingly provided on the disc.

10. The sample observation device in a secondary ion mass spectrometer according to claim 9, characterized in that: The straight line where the ion incident hole and the electron incident hole are located is perpendicular to the straight line where the observation hole and the light incident hole are located.

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