Device and method for measuring neutralization efficiency of low-energy particle beam

Abstract

The invention belongs to the technical field of low-energy particle beam application, and particularly discloses a low-energy particle beam neutralization efficiency measuring device and method, and the device comprises a sampling electrode, a grounding shielding cover, an ion deflection power supply, a controller, a suppression electrode power supply, a suppression electrode disposed in the grounding shielding cover, a receiving target, a focusing part, and a detector. One end of the sampling electrode is provided with a sampling hole, and the other end is connected with the grounding shielding case; one end of the grounding shielding cover is provided with a through hole, the suppression electrode is close to one side of the sampling electrode and is provided with a central hole, the receiving target is arranged on one side, far away from the sampling electrode, of the suppression electrode, one side of the receiving target is provided with a receiving target film, the focusing piece is arranged on one side, far away from the suppression electrode, of the receiving target, and the detector is arranged on one side, far away from the receiving target, of the focusing piece; the ion deflection power supply is electrically connected with the sampling electrode, the suppression electrode power supply is electrically connected with the suppression electrode, and the controller is in signal connection with the detector. According to the invention, the problem of low-energy neutral beam neutralization rate measurement can be solved, and the measurement precision is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of low-energy particle beam application, in particular to a low-energy particle beam current neutralization efficiency measuring device and method. BACKGROUND

[0002] In the field of low-energy particle beam application, beam current neutralization efficiency (characterized by ion equivalent current) and beam current neutral particle ratio (neutral particle ratio in total particle number) are core indicators for evaluating beam current quality and transmission efficiency. For example, in the process of semiconductor wafer ion implantation, low neutralization efficiency of beam current will cause wafer surface charge accumulation, causing device damage. Therefore, accurate measurement of the neutralization efficiency of low-energy particle beam current is a key link to ensure the stable operation of related equipment and the reliability of experimental results.

[0003] With the increasing demand for beam current parameter accuracy in application scenarios, it is necessary to accurately measure the neutralization efficiency required in semiconductor process to meet the performance requirements of particle beams for etching process. The traditional particle beam neutralization rate is measured by secondary electron current detection or calorimetry. The secondary electron current detection is to collect the secondary electron current generated by ion or high-energy neutral particles (energy > 500eV argon plasma neutral beam) bombardment through a metal target (such as a molybdenum target). The energy adaptability is limited: secondary electron current detection is only suitable for neutral particles with energy > 500eV. For low-energy neutral particles below this threshold, the number of secondary electrons generated by bombarding the metal target is very small, the current signal is weak and the signal-to-noise ratio is low, and it is difficult to effectively distinguish between ion and neutral particle contributions. Calorimetry also has difficulty in generating detectable temperature changes due to insufficient energy deposition of low-energy particles, resulting in a measurement error of > 15% for low-energy (< 500eV) beam current neutralization efficiency.

[0004] In summary, the existing low-energy particle beam current neutralization efficiency measurement scheme has significant limitations in precision, scope of application, operation convenience and stability, and there is an urgent need for a new measurement device and method that can break through the above bottlenecks to meet the increasingly stringent application requirements. SUMMARY

[0005] The present application provides a low-energy particle beam current neutralization efficiency measuring device and method, aiming to solve the problem of low-energy neutral beam current neutralization rate measurement and improve measurement accuracy.

[0006] The present application is implemented by the following technical scheme: a low-energy particle beam current neutralization efficiency measuring device, comprising a sampling electrode, a grounded shield, an ion deflection power supply, a controller, an inhibition electrode power supply, an inhibition electrode arranged inside the grounded shield, an acceptance target, a focusing element and a detector.

[0007] The sampling electrode and the grounding shield are both in a cylindrical structure, the sampling electrode comprises a deflection electrode, a grounding electrode and an insulating piece, one end of the sampling electrode is provided with a sampling hole for collecting a particle beam, and the other end is fixedly connected with the grounding shield;

[0008] The grounding shield is coaxially provided with a through hole at one end connected with the sampling electrode, and the suppression electrode is located inside the grounding shield and close to one side of the sampling electrode, and the suppression electrode is provided with a central hole coaxially arranged with the through hole of the grounding shield;

[0009] The receiving target is arranged at a side of the suppression electrode away from the sampling electrode, and the receiving target is provided with a receiving target film at a side facing the suppression electrode, the focusing piece is arranged at a side of the receiving target away from the suppression electrode, and the detector is arranged at a side of the focusing piece away from the receiving target;

[0010] The ion deflection power supply is electrically connected with the sampling electrode, the suppression electrode power supply is electrically connected with the suppression electrode, and the controller is signal connected with the detector.

[0011] Compared with the prior art, the present application has the following advantages and beneficial effects:

[0012] In the low-energy particle beam neutralization efficiency measuring device, the deflection electrode and the grounding electrode in the sampling electrode cooperate to form a stable electric field under the power supply of the ion deflection power supply, so that the ions and neutral particles in the low-energy particle beam (<500eV) can be efficiently separated, and the problems of weak response of the traditional secondary electron detection method to low-energy neutral particles and large measurement error caused by insufficient energy deposition of the calorimetric method are solved. At the same time, the cooperative design of the receiving target, the focusing piece and the detector can accurately capture the energy deposition signal of the particle bombarding the target surface, and combined with subsequent integral calculation, the measurement error of the low-energy particle beam neutralization efficiency is significantly reduced, and the precision is obviously improved compared with the traditional measurement method.

[0013] The sampling electrode and the grounding shield adopt a cylindrical structure, and the sampling hole, the through hole of the grounding shield and the central hole of the suppression electrode are coaxially arranged, which can ensure the transmission of the particle beam along a fixed path and reduce particle scattering interference; in cooperation with the energy deposition characteristics of the receiving target and the signal converging effect of the focusing piece, the detector can accurately capture the two-dimensional temperature rise distribution of the target surface.

[0014] Further, the end of the sampling electrode is a sampling hole plate, the sampling hole is arranged on the sampling hole plate, the deflection electrode and the grounding electrode are respectively located at the left side and the right side of the sampling hole, and the insulating piece comprises a first insulating ceramic and a second insulating ceramic, and the first insulating ceramic and the second insulating ceramic are respectively located at the lower side and the upper side of the sampling hole plate.

[0015] Beneficial effects: The sampling plate, as a dedicated support structure for the sampling aperture, can accurately position the aperture, ensuring that the particle beam enters the device along a fixed axis. Simultaneously, the deflection electrode and grounding electrode are positioned on the left and right sides of the sampling aperture, forming a symmetrical electric field focused on the aperture. After the ion deflection power supply is activated, the electric field intensity is uniformly distributed in the sampling aperture area, applying a directional and stable deflection force to the ion components in the low-energy particle beam, achieving complete separation of ions and neutral particles. Compared to the weak response of traditional secondary electron detection methods to low-energy particles, this structure allows neutral particles to pass through subsequent components without interference along the coaxial direction, laying the foundation for accurate detection and effectively solving the core problem of measuring the neutralization efficiency of low-energy beams.

[0016] The first and second insulating ceramics are respectively disposed on the upper and lower sides of the sampling aperture plate. On the one hand, they achieve physical isolation between the deflection electrode and the grounding electrode, avoiding electric field failure caused by electrode short circuit, and ensuring the symmetry and stability of the overall structure of the sampling electrode. On the other hand, the insulating ceramic material has the characteristics of high temperature resistance and ion bombardment resistance, which can adapt to the harsh environment brought by particle beam bombardment and reduce component wear.

[0017] Furthermore, both the sampling electrode and the grounding shield are waist-shaped cylindrical structures with a waist-shaped cross-section, and both the first insulating ceramic and the second insulating ceramic are semi-circular structures.

[0018] Beneficial effects: The sampling electrode adopts a waist-shaped cylindrical structure, combined with semi-circular first and second insulating ceramics (adapted to the arc-shaped ends of the waist-shaped structure). This allows the deflection electrode and the grounding electrode to form a focused symmetrical electric field along the axial direction of the waist-shaped cylinder. The arc-shaped profile of the waist-shaped cross-section guides the electric field lines to converge towards the sampling aperture, avoiding electric field dispersion. For low-energy ions, this structure enables the electric field force to be concentrated on the particle beam passing through the sampling aperture, ensuring that the ions receive a stable deflection force and achieving complete separation of ions from neutral particles. This solves the problems of incomplete separation of low-energy particles and significant signal interference in traditional technologies. Simultaneously, the matching axial length and radial dimensions of the waist-shaped cylindrical structure further constrain the electric field range and reduce energy loss caused by electric field leakage.

[0019] Furthermore, the grounding shield is made of stainless steel or molybdenum, and the diameter of the through hole at the end of the grounding shield is larger than the diameter of the sampling hole of the sampling electrode.

[0020] Beneficial effects: Both stainless steel and molybdenum possess excellent conductivity, magnetic shielding performance, and high-temperature resistance. When the grounding shield is made of these materials, it forms a closed electromagnetic protection cavity, effectively shielding the interference of electromagnetic radiation and stray electric fields from the external environment on the transmission and detection signals of the particle beam inside the device. This solves the problems of high signal noise and disordered ion deflection electric field caused by insufficient shielding in traditional measuring devices. Simultaneously, the through-hole at the end of the grounding shield is coaxially arranged with the sampling hole, and the diameter of the through-hole is larger than that of the sampling hole, forming a transmission channel with a small entrance and a large transition. This allows for precise acquisition of the target particle beam through the sampling hole while avoiding scattering losses caused by channel contraction when the particle beam enters the grounding shield. It guides the particle beam to be stably transmitted along the coaxial direction to the subsequent suppression electrode and receiving target, ensuring the directionality of particle transmission.

[0021] Furthermore, the small aperture design of the sampling hole enables precise sampling of the particle beam, preventing irrelevant stray particles from entering the device. Meanwhile, the larger aperture design of the grounding shield effectively reduces collision losses during particle beam transmission. This is especially important for low-energy particles, whose kinetic energy is weak. If the aperture of the grounding shield is similar to or smaller than the sampling hole, collisions between particles and the hole wall can easily reduce transmission efficiency, affecting the strength of the detection signal. This differentiated aperture design—small sampling hole, large shielding shield aperture—maximizes the particle beam throughput while ensuring sampling accuracy. This ensures a sufficient number of particles bombard the receiving target membrane, enabling the detector to capture a clear temperature rise signal and avoiding measurement failures caused by weak signals in traditional low-energy particle detection.

[0022] Furthermore, the suppression electrode is made of molybdenum material.

[0023] Beneficial effects: Molybdenum materials have high work function characteristics. When a particle beam bombards the surface of the suppressor, the secondary electron emission coefficient is lower, which can reduce the secondary electrons generated by the suppressor itself due to particle collisions and avoid additional electron interference with particle beam transmission and detection signals.

[0024] Furthermore, the surface of the receiving target facing the suppression electrode has a mounting hole, the receiving target film is fixed in the mounting hole, and the thickness of the receiving target film is 100-500μm.

[0025] Beneficial effects: The receiver target film adopts an ultra-thin design of 100-500μm. Compared with the thick target of traditional calorimetry, the energy of low-energy (<500eV) particles can be rapidly and concentratedly deposited on the surface of the target film, avoiding energy loss caused by conduction to the deeper layers of the target. This solves the problem of insufficient energy deposition of low-energy particles and inability to generate detectable temperature changes in traditional calorimetry. At the same time, the receiver target film is fixed in the mounting hole, forming an independent energy deposition area, ensuring that the energy of the particle beam bombardment is concentrated on the target film. This allows the detector to capture a clear temperature rise signal, providing a basis for subsequent measurement calculations and significantly reducing the measurement error of low-energy beam neutralization efficiency.

[0026] The ultrathin receiving target film has a small heat capacity, allowing for a rapid and detectable temperature rise after particle beam bombardment. Within this detection cycle, which is on the order of hundreds of milliseconds, the lateral heat transfer range of the receiving target film is extremely small (heat is concentrated in the bombardment area), effectively avoiding signal ambiguity caused by heat diffusion. Combined with the fixing and limiting effect of the mounting holes on the target film, the spatial range of energy deposition can be precisely defined, enabling the detector to capture the two-dimensional temperature rise distribution and ultimately achieve high spatial resolution.

[0027] Furthermore, the receiving target is made of stainless steel, and the receiving target membrane is made of stainless steel or molybdenum.

[0028] Beneficial effects: The receiving target in this solution is made of stainless steel, which has high mechanical strength and strong resistance to deformation. It can provide a stable support substrate for the receiving target membrane, avoid deformation of the mounting holes due to particle beam bombardment or temperature changes, and ensure the fixing accuracy and coaxial positioning of the receiving target membrane. At the same time, stainless steel has strong corrosion resistance and can adapt to slight oxidation or pollution in the working environment of the device, extending the overall service life of the receiving target.

[0029] The target film is made of stainless steel or molybdenum. Molybdenum has a melting point as high as 2623℃, while stainless steel has a melting point of approximately 1450℃. Both materials can withstand the localized high temperatures and sputtering losses caused by low-energy particle bombardment. Furthermore, their high hardness reduces surface wear and detachment caused by particle impacts, preventing target film damage from affecting the continuity of detection. Compared to ordinary metal materials, this material combination significantly improves the reliability of the target film in high-frequency, long-term online detection scenarios (such as continuous semiconductor manufacturing), and significantly extends the maintenance cycle.

[0030] Furthermore, the detector is an infrared thermometer, and the focusing element is a lens; the voltage range of the ion deflection power supply is continuously adjustable from 0 to 1000V, the positive terminal of the ion deflection power supply is electrically connected to the deflection electrode, and the negative terminal of the ion deflection power supply is connected to the ground electrode; the voltage range of the suppression electrode power supply is continuously adjustable from 0 to 100V, the negative terminal of the suppression electrode power supply is connected to the suppression electrode, and the positive terminal of the suppression electrode power supply is connected to the ground electrode.

[0031] Beneficial effects: The detector uses an infrared thermometer, which, together with the focusing function of the lens, can gather and accurately convert the temperature rise signal of the receiving target film into two-dimensional temperature distribution data, solving the problem that traditional calorimetry has weak response to low-energy particle energy deposition and difficulty in capturing signals.

[0032] The ion deflection power supply features a continuously adjustable design from 0-1000V, with the positive terminal connected to the deflection electrode and the negative terminal connected to the ground electrode. This allows for flexible adjustment of the electric field strength based on the energy specifications of the low-energy particle beam. For low-energy ions, a directional and stable electric field is formed by applying an appropriate voltage, ensuring that the ions are completely deflected and separated under the influence of the electric field force, preventing them from bombarding the receiving target membrane. Neutral particles, unaffected by the electric field, are precisely transported to the target membrane along a coaxial path, enabling separate detection of pure neutral particles and total particles (ions + neutral particles). Compared to the limitations of traditional secondary electron detection methods that cannot effectively distinguish between low-energy ions and neutral particles, this design ensures the purity of the detection signal from the source, making the neutralization efficiency calculation more accurate.

[0033] The suppressor power supply adopts a 0-100V continuously adjustable design, with the negative terminal connected to the suppressor and the positive terminal connected to the ground electrode. By applying a reverse voltage, a reverse electric field can be formed, which can effectively intercept secondary electrons generated by particle bombardment of the receiving target film and prevent secondary electrons from backscattering into the sampling area or interfering with the detector signal.

[0034] The wide voltage adjustment range of the ion deflection power supply and the suppression electrode power supply can be adapted to the detection requirements of low-energy particle beams of different energy specifications. Without changing the device structure, the beam parameters of different processes such as semiconductor wafer ion implantation and etching can be matched simply by adjusting the power supply voltage.

[0035] Furthermore, a method for measuring the neutralization efficiency of a low-energy particle beam, employing any of the aforementioned low-energy particle beam neutralization efficiency measuring devices, includes the following steps:

[0036] Turn on the neutral beam source, and position the low-energy particle beam neutralization efficiency measuring device directly opposite the neutral beam source outlet, within a range of 50-150 mm from the neutral beam source outlet;

[0037] The ion deflection power supply is turned off, and a suppression voltage of -50 to -150V is provided to the suppression electrode through the suppression electrode power supply. This allows the particle beam to enter the low-energy particle beam neutralization efficiency measurement device through the sampling aperture. The electric field generated by the deflection electrode deflects and separates the ion components in the beam. The neutral particle components pass sequentially through the through-hole of the grounding shield and the central hole of the suppression electrode before bombarding the receiving target film on the receiving target. The temperature rise on the back of the receiving target is measured and recorded by the detector within 100-800ms, thus obtaining the temperature rise distribution on the back of the receiving target. The total particle detection intensity value Itotal is obtained by integrating the energy density of the receiving target surface.

[0038] The ion deflection power supply is activated, and a deflection voltage is applied to the deflection electrodes to deflect and separate the ion components in the beam. Neutral particles bombard the receiving target, and the temperature rise on the back side of the receiving target is recorded and measured within 100-800 ms to obtain the temperature rise distribution on the back side of the receiving target. The neutral particle detection intensity value Ineutral is obtained by integrating the energy density of the target surface of the receiving target.

[0039] According to the formula Calculate the neutralization efficiency of a low-energy particle beam .

[0040] Beneficial Effects: This method achieves separate detection of total particles (ions + neutral particles) and pure neutral particles through two measurement logics involving turning the ion deflection power supply on and off. This solves the problems of traditional secondary electron detection methods failing to distinguish between low-energy ions and neutral particles, and calorimetric methods resulting in large errors due to insufficient energy deposition. The first measurement (with the deflection power supply off) captures the total particle energy deposition; the second measurement (with the deflection power supply on) deflects the ions through an electric field, capturing only the neutral particle energy deposition. The two integrated results (Itotal, Ineutral) are then calculated using a formula. The calculation directly locks in the core parameters of neutral efficiency.

[0041] Furthermore, by integrating the energy density of the target surface using the following formula, the energy density of the target surface can be obtained. for:

[0042] ;

[0043] in For specific heat capacity, To determine the thickness of the target receiving membrane within the target, To accept the density of the target membrane, Temperature rise distribution on the back of the receiving target as measured by the detector.

[0044] Beneficial effects: The formula in this scheme directly represents the two-dimensional temperature rise distribution of the receiving target membrane. With target surface energy density Linear correlation, where (Specific heat capacity) (Accepting target film thickness) The density of the receiving target film ((receiving target film density)) are all inherent physical parameters of the target film material, exhibiting strong stability and precise calibrability. For low-energy particles, their energy deposition is negligible, making direct quantification difficult using traditional methods. However, this formula converts the temperature rise signal into energy density, transforming minute temperature changes (precisely captured by the detector) into calculable energy parameters, thus solving the core challenge of quantifying low-energy particle energy deposition. Combined with the rapid energy deposition characteristics of 100-500μm ultrathin receiving target films, the correlation between energy density and temperature rise becomes more direct, avoiding signal distortion caused by energy conduction in thick target bodies, and providing accurate basic data for subsequent integration calculations. Attached Figure Description

[0045] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0046] Fig. 1 This is a schematic diagram of an embodiment of a low-energy particle beam neutralization efficiency measurement device according to the present invention;

[0047] Fig. 2 This is a cross-sectional view of the sampling electrode in an embodiment of a low-energy particle beam neutralization efficiency measurement device of the present invention.

[0048] The attached diagram shows the markings and corresponding component names:

[0049] Sampling electrode 1, grounding shield 2, receiving target membrane 3, lens 4, detector 5, receiving target 6, suppression electrode 7, ion deflection power supply 8, controller 9, suppression electrode power supply 10, sampling orifice plate 16, deflection electrode 17, first insulating ceramic 18, second insulating ceramic 19, sampling hole 20, grounding electrode 21. Detailed Implementation

[0050] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0051] As one embodiment of this application, such as Figs. 1-2 As shown, this embodiment provides a low-energy particle beam neutralization efficiency measurement device, including a sampling electrode 1, a grounded shield 2, an ion deflection power supply 8, a controller 9, a suppression electrode power supply 10, a suppression electrode 7 disposed inside the grounded shield 2, a receiving target 6, a focusing element, and a detector 5.

[0052] Both the sampling electrode 1 and the grounding shield 2 are cylindrical structures. The sampling electrode 1 includes a deflection electrode 17, a grounding electrode 21 and an insulating component. One end of the sampling electrode 1 is provided with a sampling hole 20 for collecting particle beams, and the other end is fixedly connected to the grounding shield 2. In this embodiment, the left end of the sampling electrode 1 and the right end of the grounding shield 2 are fixedly connected by screws.

[0053] The grounding shield 2 is connected to the sampling electrode 1 at one end and has a through hole coaxially. In this embodiment, the right end of the grounding shield 2 is the end cap of the grounding shield 2 and the through hole is opened on the end cap. The suppression electrode 7 is located inside the grounding shield 2 and close to the sampling electrode 1. The suppression electrode 7 has a central hole, which is coaxially arranged with the through hole of the grounding shield 2.

[0054] The receiving target 6 is disposed on the side of the suppressor 7 away from the sampling electrode 1. The receiving target 6 is provided with a receiving target film 3 on the side facing the suppressor 7. The focusing element is disposed on the side of the receiving target 6 away from the suppressor 7. The detector 5 is disposed on the side of the focusing element away from the receiving target. In this embodiment, the detector 5 is an infrared thermometer with a two-dimensional distribution, and the focusing element is a lens 4.

[0055] The ion deflection power supply 8 is electrically connected to the sampling electrode 1, the suppression power supply 10 is electrically connected to the suppression electrode 7, and the controller 9 is signal-connected to the detector 5.

[0056] In one embodiment, such as Fig. 2 As shown, the end of the sampling electrode 1 is a sampling aperture plate 16, and the sampling hole 20 is opened on the sampling aperture plate 16. The deflection electrode 17 and the grounding electrode 21 are located on the left and right sides of the sampling hole 20, respectively. The insulating component includes a first insulating ceramic 18 and a second insulating ceramic 19, which are located on the lower and upper sides of the sampling aperture plate 16, respectively.

[0057] In one embodiment, such as Fig. 2 As shown, both the sampling electrode 1 and the grounding shield 2 are waist-shaped cylindrical structures with a waist-shaped cross-section. In this embodiment, the first insulating ceramic 18 and the second insulating ceramic 19 are both semi-circular structures. The first insulating ceramic 18 and the second insulating ceramic 19 are located at the two semi-circular ends of the waist-shaped cylindrical structure, and the two ends of the first insulating ceramic 18 and the second insulating ceramic 19 are in contact with the deflection electrode 17 and the grounding electrode 21, respectively, to provide insulation. In this embodiment, the first insulating ceramic 18 and the second insulating ceramic 19 are respectively disposed on the upper and lower sides of the sampling aperture plate 16. On the one hand, this achieves physical isolation between the deflection electrode and the grounding electrode, avoiding short circuits that could lead to electric field failure, while also ensuring the symmetry and stability of the overall structure of the sampling electrode. On the other hand, the insulating ceramic material has the characteristics of high temperature resistance and resistance to ion bombardment, which can adapt to the harsh environment brought about by particle beam bombardment and reduce component wear.

[0058] In this embodiment, the distance between the deflection electrode 17 and the grounding electrode 21 is 10-15mm, the sampling hole 20 is located in the center of the sampling hole plate 16, and the diameter φ of the sampling hole 20 is 3-5mm.

[0059] In one embodiment, the grounding shield 2 is made of stainless steel or molybdenum. The diameter of the through hole at the end of the grounding shield 2 is larger than the diameter of the sampling hole 20 of the sampling electrode 1, and the through hole is coaxially arranged with the sampling hole 20. The diameter φ of the through hole is 5-8mm. The small diameter design of the sampling hole enables accurate sampling of the particle beam and avoids irrelevant stray particles from entering the device. The larger diameter design of the through hole of the grounding shield can effectively reduce the collision loss of the particle beam during transmission. Especially for low-energy particles, whose kinetic energy is weak, if the diameter of the through hole is equal to or smaller than that of the sampling hole, the transmission efficiency will decrease due to the collision between the particles and the hole wall, affecting the strength of the detection signal.

[0060] In one embodiment, the suppressor 7 is made of molybdenum material, and the diameter φ of the central hole on the suppressor 7 is 5-10 mm.

[0061] In one embodiment, the surface of the receiving target 6 facing the suppressor 7 has a mounting hole, and the receiving target membrane 3 is fixed in the mounting hole. In this embodiment, the thickness of the receiving target membrane 3 is 100-500μm, and the diameter φ of the mounting hole is 5-10mm.

[0062] In this embodiment, the receiving target 6 is made of stainless steel, and the receiving target membrane 3 is made of stainless steel or molybdenum. The ultra-thin receiving target membrane has a small heat capacity, allowing for a rapid and detectable temperature rise after particle beam bombardment. Furthermore, within this detection cycle on the order of hundreds of milliseconds, the lateral heat transfer range of the receiving target membrane is extremely small (heat is concentrated in the bombardment area), effectively avoiding signal ambiguity caused by heat diffusion. Combined with the fixing and limiting effect of the mounting holes on the target membrane, the spatial range of energy deposition can be precisely defined, enabling the detector to capture the two-dimensional temperature rise distribution and ultimately achieve high spatial resolution.

[0063] In one embodiment, the voltage range of the ion deflection power supply 8 is continuously adjustable from 0 to 1000V. The positive terminal of the ion deflection power supply 8 is electrically connected to the deflection electrode 17, and the negative terminal of the ion deflection power supply 8 is connected to the ground electrode 21. The voltage range of the suppression electrode power supply 10 is continuously adjustable from 0 to 100V. The negative terminal of the suppression electrode power supply 10 is connected to the suppression electrode 7, and the positive terminal of the suppression electrode power supply 10 is connected to the ground electrode 21.

[0064] In another embodiment, this embodiment provides a method for measuring the neutralization efficiency of a low-energy particle beam. This method employs a low-energy particle beam neutralization efficiency measuring device as described in the above embodiment, and includes the following steps:

[0065] Turn on the neutral beam source, and place the low-energy particle beam neutralization efficiency measurement device of the above embodiment directly opposite the neutral beam source outlet, within a range of 50-150mm from the neutral beam source outlet.

[0066] The ion deflection power supply is turned off, and a suppression voltage of -50 to -150V is provided to the suppression electrode through the suppression electrode power supply. This allows the low-energy particle beam to enter the low-energy particle beam neutralization efficiency measurement device through the sampling hole of the sampling electrode. The electric field generated by the deflection electrode deflects and separates the ion components in the beam. The neutral particle components pass through the through-hole of the grounding shield and the central hole of the suppression electrode in a coaxial direction, and then bombard the receiving target film on the receiving target. The temperature rise on the back of the receiving target is measured and recorded by the detector within 100-800ms, obtaining the temperature rise distribution on the back of the receiving target. This is used to characterize the energy distribution of the beam deposited on the front of the target. Let dQ be the energy deposited onto a micro-element of the target surface after irradiation.

[0067] (1),

[0068] Then the energy density of the target surface is received. for:

[0069] (2),

[0070] in For specific heat capacity, To determine the thickness of the target receiving membrane within the target, To receive the density of the target film, dS is the area element of a tiny region on the target surface. Temperature rise distribution on the back of the receiving target as measured by the detector.

[0071] Using formula (2), the total particle detection intensity value Itotal is obtained by integrating the energy density of the receiving target surface;

[0072] The ion deflection power supply is activated, and a deflection voltage is applied to the deflection electrodes. In this embodiment, a +300V deflection voltage is applied to the deflection electrodes to deflect and separate the ion components in the beam. Neutral particles bombard the receiving target. Under the influence of the electric field, the ions are deflected to achieve separation from the neutral particles, ensuring that only neutral particles are received when the beam bombards the metal target (i.e., the receiving target). The temperature rise on the back of the receiving target is recorded and measured within 100-800ms to obtain the temperature rise distribution on the back of the receiving target. Using formula (2), the neutral particle detection intensity value Ineutral is obtained by integrating the energy density of the target surface of the receiving target;

[0073] Finally, according to the formula Calculate the neutralization efficiency of a low-energy particle beam .

[0074] In this embodiment, after the detector captures the temperature changes at different positions (x, y coordinates) of the receiving target film, it generates corresponding analog electrical signals (such as voltage and current signals). The controller receives the raw signals in real time through the signal lines. The controller is the core hub of signal acquisition, processing, transmission and application in the device. It can convert the raw temperature rise signal captured by the detector into standardized two-dimensional data that can be directly used for energy density calculation, and coordinate to ensure the accuracy, efficiency and stability of the measurement process. It is an indispensable control unit for realizing high-precision measurement of neutralization efficiency of low-energy particle beams.

[0075] It should be noted that the above description of the disclosed embodiments enables those skilled in the art to implement or use this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A device for measuring the neutralization efficiency of a low-energy particle beam, characterized in that, It includes a sampling electrode, a grounding shield, an ion deflection power supply, a controller, a suppressor power supply, a suppressor electrode disposed inside the grounding shield, a receiving target, a focusing element, and a detector; Both the sampling electrode and the grounding shield are cylindrical structures. The sampling electrode includes a deflection electrode, a grounding electrode, and an insulating component. One end of the sampling electrode is provided with a sampling hole for collecting particle beams, and the other end is fixedly connected to the grounding shield. The grounding shield has a through hole coaxially opened at one end connected to the sampling electrode. The suppression electrode is located inside the grounding shield and close to the sampling electrode. The suppression electrode has a central hole, which is coaxially arranged with the through hole of the grounding shield. The receiving target is disposed on the side of the suppressor away from the sampling electrode, and the receiving target is provided with a receiving target film on the side of the receiving target facing the suppressor. The focusing element is disposed on the side of the receiving target away from the suppressor, and the detector is disposed on the side of the focusing element away from the receiving target. The ion deflection power supply is electrically connected to the sampling electrode, the suppression electrode power supply is electrically connected to the suppression electrode, and the controller is signal-connected to the detector.

2. The low-energy particle beam neutralization efficiency measurement device according to claim 1, characterized in that, The end of the sampling electrode is a sampling orifice plate, and the sampling orifice is formed on the sampling orifice plate. The deflection electrode and the grounding electrode are located on the left and right sides of the sampling orifice, respectively. The insulating component includes a first insulating ceramic and a second insulating ceramic, which are located on the lower and upper sides of the sampling orifice plate, respectively.

3. The low-energy particle beam neutralization efficiency measurement device according to claim 2, characterized in that, Both the sampling electrode and the grounding shield are waist-shaped cylindrical structures with a waist-shaped cross-section, and both the first insulating ceramic and the second insulating ceramic are semi-circular structures.

4. The low-energy particle beam neutralization efficiency measurement device according to claim 1, characterized in that, The grounding shield is made of stainless steel or molybdenum, and the diameter of the through hole at the end of the grounding shield is larger than the diameter of the sampling hole of the sampling electrode.

5. The low-energy particle beam neutralization efficiency measurement device according to claim 1, characterized in that, The suppression electrode is made of molybdenum.

6. The low-energy particle beam neutralization efficiency measurement device according to claim 1, characterized in that, The surface of the receiving target facing the suppression electrode has a mounting hole, and the receiving target film is fixed in the mounting hole. The thickness of the receiving target film is 100-500μm.

7. The low-energy particle beam neutralization efficiency measurement device according to claim 6, characterized in that, The receiving target is made of stainless steel, and the receiving target membrane is made of stainless steel or molybdenum.

8. The low-energy particle beam neutralization efficiency measurement device according to claim 1, characterized in that, The detector is an infrared thermometer, and the focusing element is a lens; the voltage range of the ion deflection power supply is continuously adjustable from 0 to 1000V, the positive terminal of the ion deflection power supply is electrically connected to the deflection electrode, and the negative terminal of the ion deflection power supply is connected to the ground electrode; the voltage range of the suppression electrode power supply is continuously adjustable from 0 to 100V, the negative terminal of the suppression electrode power supply is connected to the suppression electrode, and the positive terminal of the suppression electrode power supply is connected to the ground electrode.

9. A method for measuring the neutralization efficiency of a low-energy particle beam, characterized in that, The method of using any one of the low-energy particle beam neutralization efficiency measurement devices according to claims 1-8 includes the following steps: Turn on the neutral beam source, and position the low-energy particle beam neutralization efficiency measuring device directly opposite the neutral beam source outlet, within a range of 50-150 mm from the neutral beam source outlet; The ion deflection power supply is turned off, and a suppression voltage of -50 to -150V is provided to the suppression electrode through the suppression electrode power supply. This allows the particle beam to enter the low-energy particle beam neutralization efficiency measurement device through the sampling aperture. The electric field generated by the deflection electrode deflects and separates the ion components in the beam. The neutral particle components pass sequentially through the through-hole of the grounding shield and the central hole of the suppression electrode before bombarding the receiving target film on the receiving target. The temperature rise on the back of the receiving target is measured and recorded by the detector within 100-800ms to obtain the temperature rise distribution on the back of the receiving target. The total particle detection intensity value Itotal is obtained by integrating the energy density of the receiving target surface. The ion deflection power supply is activated, and a deflection voltage is applied to the deflection electrodes to deflect and separate the ion components in the beam. Neutral particles bombard the receiving target, and the temperature rise on the back side of the receiving target is recorded and measured within 100-800 ms to obtain the temperature rise distribution on the back side of the receiving target. The neutral particle detection intensity value Ineutral is obtained by integrating the energy density of the target surface of the receiving target. According to the formula Calculate the neutralization efficiency of a low-energy particle beam .

10. A method for measuring the neutralization efficiency of a low-energy particle beam according to claim 9, characterized in that, The energy density of the receiving target surface can be obtained by integrating the energy density of the receiving target surface using the following formula. for: ； in For specific heat capacity, To determine the thickness of the target receiving membrane within the target, To accept the density of the target membrane, Temperature rise distribution on the back of the receiving target as measured by the detector.

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