Radio-frequency extraction high-energy hydrogen-helium ion implanter

Abstract

The embodiments of the present disclosure relate to the technical field of semiconductor ion implantation. Provided is a radio-frequency extraction high-energy hydrogen-helium ion implanter. The specific implementation of the radio-frequency extraction high-energy hydrogen-helium ion implanter comprises: generating an alternating voltage of a radio-frequency extraction electrode by means of a radio-frequency power supply and a first radio-frequency acceleration unit; the alternating voltage periodically extracting ion beams from an ion source; by means of the dispersion of velocity, causing the ion beams to periodically cluster in a Z-axis transmission direction; shaping the ion beams by means of a first beam-shaping electrostatic quadrupole lens and a second beam-shaping electrostatic quadrupole lens, and then transmitting same to a radio-frequency acceleration system; transmitting the ion beams, which have been accelerated to a high-energy state by the radio-frequency acceleration system, to an energy analyzer for screening; expanding, by means of an electric-field scanning system, the ion beams screened by the energy analyzer, and then making the expanded ion beams pass through a beam parallelization lens, such that parallel ion beams are produced; and finally, transmitting the parallel ion beams to a target chamber to complete implantation. The implementation can reduce the size of a high-energy ion implanter, reduce the machine footprint, and reduce the implantation costs.

Description

A radio frequency-induced hydrogen-helium high-energy ion implanter

[0001] This application claims priority to a Chinese application filed with the Patent Office of China on November 27, 2023, with application number CN202311591496.X and application name “A Radio Frequency Induced Hydrogen-Helium High-Energy Ion Implantation Machine”, all contents of which are incorporated by reference into this application. Technical Field

[0002] The present disclosure relates to the technical field of semiconductor ion implantation, and in particular to a radio frequency induced hydrogen and helium high-energy ion implanter. Background Art

[0003] A key step in semiconductor device manufacturing is the implantation of ions into a semiconductor wafer in a vacuum, introducing impurities into the wafer's crystal lattice and altering its conductivity. This process is performed using an ion implanter, which typically ionizes semiconductor impurity atoms into ions, accelerates them, and then implants them into the semiconductor wafer.

[0004] With the high integration of semiconductor components, it is necessary to implant high-energy ions deeper into the semiconductor wafer. The corresponding device is called a high-energy ion implanter. The components used for ion beam acceleration in high-energy ion implanters usually use a tandem electrostatic accelerator. The structure of the electrostatic accelerator gradually increases in complexity as the voltage increases. The gradually increasing insulation distance will significantly increase the physical size of the equipment. At the same time, the acceleration voltage is generally less than 500kV. For processes that require high-energy MeV (Million Electron Volts) injection, the electrostatic accelerator cannot meet the energy requirements of different scenarios. Therefore, linear accelerators that use the radio frequency acceleration principle and can accelerate ions to MeV energy (Patent.No.US4667111) have gradually become widely used. When a high-energy ion implanter uses an RF acceleration system, various ions generated by the ion source are extracted by an extraction voltage, filtered by a mass analyzer, and then enter the RF acceleration system to accelerate as many ion beams as possible to the required energy. The ions with the required energy are then filtered by the energy analyzer, scanned and parallelized, and injected into the wafer in the target chamber.

[0005] High-energy ion implanters previously used batch systems. However, for high-quality imaging devices such as CCDs, which require ultra-high-energy ion implantation (3-8 MeV) and have an allowable implantation angle error of approximately 0.1°, batch systems with large implantation angle deviations are difficult to use. Consequently, single-wafer high-energy ion implanters have been put into use in recent years. These parallelize the one-dimensional electrically scanned ion beam, achieving not only uniform implantation dose across the wafer surface but also uniform implantation angles, thus resolving the implantation angle deviation issue.

[0006] The extraction electrode of the high-energy ion implanter uses a DC voltage. In order to achieve the effect of ion beam clustering, the Buncher (i.e., buncher) technology is introduced to improve the clustering effect of the ion beam in the radio frequency acceleration system to increase the longitudinal pass rate of the beam. The Buncher is introduced to the front end of the radio frequency acceleration system (Patent.No.CN1310279C). Since the longitudinal clustering of the beam requires a certain space to complete, the radio frequency acceleration barrel of the radio frequency acceleration system needs to maintain a certain distance from the Buncher, which invisibly increases the length of the radio frequency acceleration system, resulting in an increase in the volume of the radio frequency acceleration system and an increase in the machine area. On the other hand, the high-energy ion implanter requires a mass analyzer to screen the ion mass, which is also bulky and increases the cost of the machine.

[0007] Summary of the Invention

[0008] In view of this, the embodiments of the present disclosure provide a radio frequency-induced hydrogen-helium high-energy ion implanter, which can solve the problems of existing high-energy ion implanters being bulky, occupying a large area, and having excessively high implantation costs.

[0009] To achieve the above objectives, according to one aspect of the present disclosure, a radio frequency hydrogen-helium high-energy ion implanter is provided, comprising:

[0010] Ion source, radio frequency extraction electrode, suppression electrode, three-coordinate ground electrode, first beam shaping electric quadrupole lens, second beam shaping electric quadrupole lens, radio frequency acceleration system, energy analyzer, electric field scanning system, beam parallelization lens and target chamber, wherein:

[0011] The alternating voltage of the RF extraction electrode is generated by the RF power supply and the first RF acceleration unit. The alternating voltage periodically extracts an ion beam from the ion source. The discreteness of the velocity causes the ion beam to generate periodic clustering in the Z-direction transmission direction. After being shaped by the first beam shaping electric quadrupole lens and the second beam shaping electric quadrupole lens, the ion beam is transmitted to the RF acceleration system. The ion beam accelerated to a high energy state by the RF acceleration system is transmitted to the energy analyzer for screening. The ion beam after screening by the energy analyzer is expanded in at least one direction by the electric field scanning system, and then a parallel ion beam flow is generated by the beam parallelization lens. Finally, the ion beam is transmitted to the target chamber to complete the injection.

[0012] One or more technical solutions provided in the embodiments of the present application can achieve the following technical effects by applying an alternating voltage to the RF extraction electrode through the RF power supply and the first RF acceleration unit, eliminating the mass analyzer and the buncher:

[0013] (1) The RF extraction electrode combines the functions of the Buncher and the DC extraction electrode into one, so that the RF acceleration system of the high-energy ion implanter does not need to be equipped with a Buncher. It provides an injection solution with a simple and compact structure and a large beam current for the lightweight hydrogen and helium high-energy ion implantation, which has the advantages of saving machine space and reducing beam loss.

[0014] (2) The ions extracted by the radio frequency extraction hydrogen-helium high-energy ion implanter disclosed herein are highly homogeneous, and there is no need to set up a mass analyzer. The filtering characteristics of the radio frequency extraction electrode, the shaped electric quadrupole lens, and the radio frequency acceleration system can be used to screen and accelerate specific low relative atomic mass ions. Even if ions or electrons related to the elements in the ion source chamber are generated and enter the radio frequency acceleration system, due to the large difference in their charge-to-mass ratio with hydrogen and helium, stray particles are difficult to accelerate and can be easily filtered using an energy analyzer. Therefore, by abandoning the bulky mass analyzer, it is also possible to save machine space and reduce machine costs.

[0015] (3) The RF extraction electrode directly interacts with the ion beam. In principle, a power supply with a DC voltage difference needs to be attached to the RF extraction electrode to suppress electrons from entering the beam transmission system. Usually, an isolation transformer can be used to apply high voltage to the ion source to achieve the same effect. Since the amplitude of the alternating voltage applied to the RF extraction electrode is greatly reduced (for example, 30 kV peak-to-peak), compared with the traditional 70-90 kV DC ion source voltage, the volume and weight of the isolation transformer are greatly reduced, and can even be omitted, further saving machine space and reducing machine costs.

[0016] (4) The shape of the RF extraction electrode needs to be determined according to the structure of the ion source extraction slit. The shape and size of the extraction slit are closely related to the extraction flux intensity requirement. In traditional mass analyzer scenarios, when calculating the beam extraction and deflection of irregular extraction slits, either details are ignored and the transmission matrix is ​​used for calculation, or full three-dimensional electromagnetic simulation is performed. The design and simulation are very difficult, which delays the development of new models and only allows minor modifications to certain typical designs. After the present invention adopts linear extraction, the beam optics can present a two-dimensional axisymmetric and mirror-symmetrical structure, which greatly reduces the difficulty of design and simulation. Many precedent scenarios of linear electron optics and ion optics can be used. Even if the extraction slit is irregular, it is relatively easy to control the size and angle of the ion beam.

[0017] (5) The lateral fluctuation of the beam caused by the RF extraction electrode is real. Therefore, the electrons that are no longer accelerated due to the premature neutralization of the positive ions of hydrogen and helium are suppressed by the suppression electrode and the three-coordinate ground electrode to prevent the electrons from entering the subsequent beam channel. The beam is then shaped and the fluctuation is suppressed from the lateral direction using the shaping electric quadrupole lens, gradually approaching the "O"-shaped beam cross section desired by the RF acceleration system.

[0018] (6) The beam profile shaping and ideal clustering disclosed in the present invention have sufficient length and can be separated from the acceleration area as much as possible. Unlike traditional high-energy ion implantation machines, the beam profile shaping and ideal beam clustering must be completed simultaneously within a limited distance between the buncher and the radio frequency acceleration system, thereby improving the shaping and acceleration effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Further details, features and advantages of the present disclosure are disclosed in the following description of exemplary embodiments in conjunction with the accompanying drawings, in which:

[0020] FIG1( a ) shows a schematic diagram of a radio frequency extraction hydrogen-helium high energy ion implanter according to an exemplary embodiment of the present disclosure;

[0021] FIG1( b ) shows a schematic diagram of a radio frequency power supply and a first radio frequency acceleration unit according to an exemplary embodiment of the present disclosure;

[0022] FIG2 shows a schematic diagram 1 of the relative relationship between the ion source voltage and the alternating voltage of the radio frequency extraction electrode according to an exemplary embodiment of the present disclosure;

[0023] FIG3 shows a second schematic diagram of the relative relationship between the ion source voltage and the alternating voltage of the radio frequency extraction electrode according to an exemplary embodiment of the present disclosure;

[0024] FIG4 shows a third schematic diagram of the relative relationship between the ion source voltage and the alternating voltage of the radio frequency extraction electrode according to an exemplary embodiment of the present disclosure;

[0025] FIG5 shows a schematic diagram of a cross section of a ribbon ion source and a radio frequency extraction electrode according to an exemplary embodiment of the present disclosure;

[0026] FIG6 shows a schematic diagram of a cross section of a spherical ion source and a radio frequency extraction electrode according to an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0027] The following describes embodiments of the present disclosure in more detail with reference to the accompanying drawings. Although certain embodiments of the present disclosure are shown in the accompanying drawings, it should be understood that the present disclosure can be implemented in various forms and should not be construed as limited to the embodiments described herein. Rather, these embodiments are provided to provide a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the present disclosure are for illustrative purposes only and are not intended to limit the scope of protection of the present disclosure.

[0028] The term "including" and its variations used in this document are open inclusions, that is, "including but not limited to". The term "based on" means "at least partially based on". The term "in an embodiment of the present disclosure" means "at least one embodiment"; the term "another exemplary embodiment" means "at least one other embodiment". The relevant definitions of other terms will be given in the following description. It should be noted that the concepts of "first", "second", etc. mentioned in this disclosure are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0029] It should be noted that the modifications of "one" and "multiple" mentioned in the present disclosure are illustrative rather than restrictive, and those skilled in the art should understand that unless otherwise clearly indicated in the context, they should be understood as "one or more".

[0030] Aspects of the present disclosure are described below with reference to the accompanying drawings.

[0031] Figure 1(a) shows a schematic diagram of a radio frequency extraction hydrogen-helium high-energy ion implanter according to an exemplary embodiment of the present disclosure. As shown in Figure 1(a), the radio frequency extraction hydrogen-helium high-energy ion implanter of the present disclosure includes: an ion source 101, a radio frequency extraction electrode 102, a suppression electrode 103, a three-coordinate ground electrode 104, a first beam shaping electric quadrupole lens 105, a second beam shaping electric quadrupole lens 106, a radio frequency acceleration system 107, an energy analyzer 108, an electric field scanning system 109, a beam parallelization lens 110 and a target chamber 111.

[0032] The RF extraction electrode 102 extracts the ion beam from the ion source 101. The discreteness of the velocity causes the ion beam to generate periodic clustering in the Z-direction transmission direction. After being shaped by the first beam shaping electric quadrupole lens 105 and the second beam shaping electric quadrupole lens 106, it directly enters the RF acceleration system 107. After being accelerated to a high energy state by the RF acceleration system 107, the energy analyzer 108 selects the ion beam of predetermined energy. The selected ion beam is transmitted to the target chamber 111 through the electric field scanning system 109 and the beam parallelization lens 110. A target stage motion mechanism is provided in the target chamber 111. The target stage motion mechanism has a motion dimension perpendicular to the scanning direction of the electric field scanning system 109, and the ion beam injection is completed in the target chamber 111.

[0033] Furthermore, the present disclosure is applicable to ions with low relative atomic mass (e.g., hydrogen or helium), and the ions drawn out have a high degree of homogeneity. For example, high-purity hydrogen gas is ionized by the ion source 101 to produce H + 、H2 + 、H3 + Alternatively, high-purity helium is ionized by ion source 101 to produce He + 、He 2+ .

[0034] In the disclosed embodiment, as shown in FIG1( a ), the ion source 101 generates positive ions of low relative atomic mass, and an alternating voltage is applied to the RF extraction electrode 102, causing the RF extraction electrode 102 to periodically extract an ion beam from the ion source 101. As shown in FIG1( b ), the alternating voltage on the RF extraction electrode 102 is generated by an RF power supply 1021 and a first RF acceleration unit 1022 , which employs a structure similar to that of a Buncher. The RF power supply 1021 feeds RF power into the first RF acceleration unit 1022 , the main structure of which is an LC resonant circuit, as described in the patent (Patent. No. US6262638), including a capacitor C and an inductor L, so that the first RF acceleration unit 1022 is always in a resonant state, and the resonant high voltage is applied to the RF extraction electrode 102 . The capacitor C and the inductor L determine the resonant frequency of the first RF acceleration unit 1022 . Due to its close proximity to the ion source 101, the vacuum near the RF extraction electrode 102 is less than ideal. Consequently, the amplitude of the sinusoidal high voltage applied to the RF extraction electrode 102 is limited, typically between 0 and 30 kV. Excessive amplitude can easily lead to electrical breakdown. However, the RF extraction electrode 102 serves only to extract ions and cluster them; it does not provide energy for ion acceleration. The final beam energy of a high-energy ion implanter is primarily provided by the RF acceleration system 107. Therefore, there is no need to apply a high voltage to the RF extraction electrode 102.

[0035] Unlike a DC power supply that extracts a uniform ion beam, the RF extraction electrode disclosed in the present invention applies an alternating voltage to extract a periodically pulsating ion beam, and as the alternating voltage changes, velocity dispersion is applied to the ions, so that the ion beam produces sparse and dense clusters in the direction of motion in subsequent motion, which can provide a good periodic ion cluster for the RF acceleration system and reduce the longitudinal beam loss in RF acceleration. On the one hand, since the RF extraction electrode 102 has the capabilities of both the DC extraction electrode of a traditional high-energy ion implanter and the Buncher in the RF system, there is no need to set up a Buncher in the RF acceleration system 107; on the other hand, the present invention is applicable to ions with low relative atomic mass. Since the extracted ions have velocity dispersion, there is no need for a mass analyzer to perform ion screening, which greatly reduces beam loss, makes beam simulation design easier, and can simplify system components for microwave ion sources that require isolation waveguides. In summary, the technical effects of saving machine space and reducing machine costs can be achieved.

[0036] As shown in Figure 1(a), the discreteness of the velocity causes the periodically extracted ion beam to produce periodic clustering in the Z-direction transmission direction. In order to prevent the electrons in the ion source 101 from being introduced into the subsequent beam channel, in addition to setting the suppression electrode 103 to suppress the electrons, the voltage of the ion source 101 can also be appropriately increased. The periodically clustered ion beam passes through the suppression electrode 103 and the three-coordinate ground electrode 104 before reaching the beam shaping area.

[0037] As shown in Figure 1(a), the movement of the suppression electrode 103 and the three-coordinate ground electrode 104 causes a change in capacitance C, resulting in a slight shift in the resonant frequency of the first RF acceleration unit 1022. Therefore, the first RF acceleration unit 1022 also includes a frequency compensation motion device to compensate for the impact of the movement of the suppression electrode 103 and the three-coordinate ground electrode 104 on the RF frequency. As shown in Figure 1(b), the RF extraction electrode 102 is close to the ion source 101 and away from the suppression electrode 103 and the three-coordinate ground electrode 104. This is also to reduce the impact of the moving suppression electrode 103 and the three-coordinate ground electrode 104 on the resonant frequency, while better controlling the extraction of the ion source 101 in the desired manner.

[0038] As shown in Figure 1(a), the beam shaping region includes a first beam shaping electric quadrupole lens 105 and a second beam shaping electric quadrupole lens 106, which are used to shape the irregular ion beam passing through the three-coordinate ground electrode 104 into the "O"-shaped beam required by the radio frequency acceleration system 107. The first beam shaping electric quadrupole lens 105 and the second beam shaping electric quadrupole lens 106 can initially suppress the disturbance of the radio frequency extraction electrode 102 on the ion beam, so that the ion beam is clustered longitudinally (i.e., in the Z direction) and prevent lateral fluctuations of the ions. At the same time, the first beam shaping electric quadrupole lens 105 and the second beam shaping electric quadrupole lens 106 can reduce the self-expansion of the low-speed ion beam before acceleration caused by space charge forces, thereby ensuring the "O" beam forming effect of the ion beam. It should be noted that the number of beam shaping electric quadrupole lenses included in the beam shaping area can be selectively set as needed. The first beam shaping electric quadrupole lens and the second beam shaping electric quadrupole lens disclosed in the present invention are only examples; alternatively, other beam optical elements can be set in the beam shaping area as needed to meet actual shaping requirements.

[0039] As shown in Figure 1(a), the RF acceleration system 107, energy analyzer 108, electric field scanning system 109, beam parallelization lens 110, and target chamber 111 are essentially the same as those of a conventional high-energy ion implanter. The ion beam accelerated to a high energy state by the RF acceleration system 107 is screened by the energy analyzer 108. The screened ion beam is then scanned in at least one direction (e.g., the X direction) by the electric field scanning system 109. The screened ion beam is then generated by the beam parallelization lens 110 to produce a parallel ion beam. Finally, the beam is transmitted to the target chamber 111 to complete the ion beam implantation. The number of second RF acceleration units 1071 and quadrupole lenses 1072 in the RF acceleration system 107 depends on the acceleration energy range covered by the implanter.

[0040] In the disclosed embodiment, the alternating voltage applied to the RF extraction electrode 102 can be a sinusoidal voltage, a triangular wave voltage, or a pulsed voltage. With the platform ground of the high-energy ion implanter as the reference ground potential, the ion source voltage 201 and the sinusoidal voltage 202 applied to the RF extraction electrode 102 are shown in FIG2 , the ion source voltage 301 and the triangular wave voltage 302 applied to the RF extraction electrode 102 are shown in FIG3 , and the ion source voltage 401 and the pulsed voltage 402 applied to the RF extraction electrode 102 are shown in FIG4 . Since positive ions are often extracted, the ion source voltages 201, 301, and 401 are generally positive and adjustable, primarily used to suppress electron extraction from the ion source 101. Ion source voltages 201, 301, and 401 are DC voltages, whose amplitudes depend on the amplitude of the AC voltage applied to the RF extraction electrode 102. However, they do not need to be as high as 70-90 kV. Compared to conventional 70-90 kV DC ion source voltages, the significantly reduced distance between the isolation transformer and the withstand voltage in the ion source region saves space and reduces the machine footprint. This significantly reduces the space and weight of the isolation transformer required by the present disclosure, and can even eliminate the need for an isolation transformer, eliminating exposed high-voltage electrodes in the source region. Furthermore, ion source voltages 201, 301, and 401 also play a crucial role in energy calibration in high-energy ion implanters.

[0041] Furthermore, as shown in FIG2 , the amplitude of the sinusoidal voltage 202 is adjustable, but generally does not exceed 30 kV, which is suitable for the extraction frequency f of ion acceleration. 引出 In the radio frequency band, 13.56MHz, 27.12MHz, and 40.68MHz are mostly used in the industrial field. In this frequency range, sinusoidal voltage is much easier to use than other types of alternating voltage. For light ions such as hydrogen and helium, the extraction frequency f 引出 The higher frequency can be considered. The extraction frequency f of the sinusoidal voltage 202 引出 The acceleration frequency f of the radio frequency acceleration system 107 加速 The relationship between is shown in the following formula (1): 加速 =n×f引出 ,(n=1,2,3,…)——(1)

[0042] In the above formula, the extraction period T of the sinusoidal voltage 202 is 引出 and the extraction frequency f 引出 The relationship between T 引出 =1 / f 引出 , among which n=1 is the easiest to implement. In the case of n=1, the alternating voltage on the RF extraction electrode 102 and the RF voltage of each second RF acceleration unit 1071 in the RF acceleration system 107 maintain homologous phase locking, which can achieve efficient acceleration, and the phase difference between the alternating voltage and each RF voltage can be adjusted to facilitate fine adjustment of the energy and ion beam current in high-energy acceleration.

[0043] As shown in FIG3 , the amplitude of the triangular wave voltage 302 is adjustable, but usually does not exceed 30 kV. The extraction frequency f of the triangular wave voltage 302 is 引出 The acceleration frequency f of the radio frequency acceleration system 107 加速 The relationship between and also satisfies the above formula (1). In the frequency range of 13.56MHz, 27.12MHz, and 40.68MHz, the generation of triangular wave voltage is much more difficult than that of sine voltage, but the triangular wave voltage can make the ion beam clustering effect better.

[0044] As shown in FIG4 , the amplitude of the pulse voltage 402 is adjustable, but usually does not exceed 30 kV. The extraction frequency f of the pulse voltage 402 is 引出 The acceleration frequency f of the radio frequency acceleration system 107 加速 The relationship between and also satisfies the above equation (1). Within the frequency range of 13.56 MHz, 27.12 MHz, and 40.68 MHz, the generation of ultra-narrow pulse voltage is much more difficult than that of sinusoidal voltage. However, because the pulse voltage of the pulse voltage is constant, the ion velocity extracted by the RF extraction electrode 102 is consistent, which can directly provide the RF acceleration system 107 with an ion cluster with small velocity dispersion, making subsequent acceleration easier.

[0045] In the disclosed embodiments, the ion beams extracted by the ion source 101 and the RF extraction electrode 102 can have various shapes. As shown in FIG5 , the ion source 101 of the disclosed RF extraction hydrogen-helium high-energy ion implanter utilizes a ribbon ion source 501. The ribbon ion source 501 extracts a ribbon ion beam. Accordingly, the through-holes of the RF extraction electrode 502, the suppression electrode 503, and the three-coordinate ground electrode 504 are all ribbon-shaped. The advantage of a ribbon beam is its high beam current. The RF extraction electrode 502 is extracted from the side of the ribbon ion source 501, while the suppression electrode 503 is still used to suppress electrons from entering the subsequent acceleration system and to suppress secondary electron bombardment. This can be selected or omitted depending on the specific situation. When the voltage on the RF extraction electrode 502 changes to a value lower than the ion source voltage of the ribbon ion source 501, positive ions are extracted and enter the through hole of the RF extraction electrode 502. After passing through the through hole of the RF extraction electrode 502, the ions are motivated to continue moving through the suppression electrode 503 and the three-coordinate ground electrode 504 because the voltage of the RF extraction electrode 502 is higher than that of the three-coordinate ground electrode 504 behind it. + and He + , it will not move as slowly as heavy ions, so the inter-electrode distances between the RF extraction electrode 502 and the ribbon ion source 501, the RF extraction electrode 502 and the suppression electrode 503, and the three-coordinate ground electrode 504 are not too small. As shown in Figure 5, the RF extraction electrode 502 is close to the extraction end of the ribbon ion source 501 and far from the suppression electrode 503 and the three-coordinate ground electrode 504, so that the electric field between the RF extraction electrode 502 and the ribbon ion source 501 is strong, which can modulate the speed of the ions. The ion beam is converted from velocity modulation to density modulation in the journey between the RF extraction electrode 502 and the suppression electrode 503. Although there is a weak electric field in this space, it is not affected and gradually begins to become a cluster of ions in the Z direction of movement. Therefore, the RF extraction electrode 502 can simultaneously achieve the two effects of extracting ions and promoting ion clustering. It should be noted that the extraction frequency f 引出 The inter-pole spacing can be simulated in detail as needed to meet the actual clustering requirements.

[0046] Alternatively, as shown in FIG6 , the ion source 101 of the radio frequency extraction hydrogen-helium high energy ion implanter disclosed in the present invention can also adopt a spherical ion source 601. The spherical ion source 601 extracts a spherical ion beam. Accordingly, the through holes of the radio frequency extraction electrode 602 and the three-coordinate ground electrode 603 are all "O"-shaped. The advantage of the spherical extraction beam is that the beam current is large and the extraction frequency f is small. 引出 The inter-pole spacing can also be designed and simulated in detail as needed to meet the actual clustering requirements.

[0047] Furthermore, when using the spherical ion source 601 , it can be determined whether a suppression electrode needs to be added based on the movement path of the electrons and the bombardment of the secondary electrons.

Claims

1. A radio frequency hydrogen-helium high energy ion implanter, characterized in that: include: An ion source (101), a radio frequency extraction electrode (102), a suppression electrode (103), a three-coordinate ground electrode (104), a first beam shaping electric quadrupole lens (105), a second beam shaping electric quadrupole lens (106), a radio frequency acceleration system (107), an energy analyzer (108), an electric field scanning system (109), a beam parallelization lens (110) and a target chamber (111), wherein: The alternating voltage of the radio frequency extraction electrode (102) is generated by a radio frequency power supply (1021) and a first radio frequency acceleration unit (1022). The alternating voltage periodically extracts an ion beam from the ion source (101). The discreteness of the speed causes the ion beam to generate periodic clustering in the Z-direction transmission direction. After being shaped by the first beam shaping electric quadrupole lens (105) and the second beam shaping electric quadrupole lens (106), the ion beam is transmitted to the radio frequency acceleration system (107). The ion beam accelerated to a high energy state by the radio frequency acceleration system (107) is transmitted to the energy analyzer (108) for screening. The ion beam screened by the energy analyzer (108) is expanded in at least one direction by the electric field scanning system (109), and then a parallel ion beam is generated by the beam parallelization lens (110). Finally, the ion beam is transmitted to the target chamber (111) to complete the injection.

2. The radio frequency extraction hydrogen-helium high energy ion implanter as claimed in claim 1, characterized in that: The extraction frequency f of the alternating voltage applied to the radio frequency extraction electrode (102) is 引出 and the radio frequency f applied to each second radio frequency acceleration unit (1071) in the radio frequency acceleration system (107) 加速 , satisfying the following relationship: 加速 =n×f 引出 , (n=1,2,3,…).

3. The radio frequency extraction hydrogen-helium high energy ion implanter as claimed in claim 1, characterized in that: The alternating voltage applied to the radio frequency extraction electrode (102) is a sinusoidal voltage, a triangular wave voltage or a pulse voltage.

4. The radio frequency hydrogen-helium high energy ion implanter as claimed in claim 1, characterized in that: The ion source (101) is a spherical ion source, and the radio frequency extraction electrode (102) is extracted from the side; Alternatively, the ion source (101) is a ribbon-shaped ion source, and the through hole of the radio frequency extraction electrode (102) is ribbon-shaped.

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