Ion source and ion beam tilt extraction device

Abstract

The application discloses an ion source and an ion beam tilting extraction device, and relates to the technical field of semiconductor processing equipment; the ion source comprises a microwave main path, a plasma chamber, a gas supply assembly, an ion beam extraction control assembly and a power supply assembly; the microwave main path comprises a microwave source, a waveguide and a residual power absorption load, the microwave source, the waveguide and the residual power absorption load are sequentially communicated, the waveguide is connected with the plasma chamber, a plurality of slot holes are formed on the waveguide and are spaced apart from each other and face the plasma chamber, and an ion beam extraction outlet is formed on the plasma chamber; the gas supply assembly is connected with the plasma chamber and is used for introducing working gas into the plasma chamber; the ion beam extraction control assembly is arranged at the ion beam extraction outlet of the plasma chamber, and the power supply assembly is electrically connected with the ion beam extraction control assembly. The application can realize uniform tilting extraction of the ion beam and can greatly improve the flexibility of process treatment.

Description

Technical Field

[0001] This invention relates to the field of semiconductor processing equipment technology, and more specifically, to an ion source and an ion beam tilting extraction device. Background Technology

[0002] In the semiconductor manufacturing field, ion implantation is one of the core technologies for material doping, surface modification, and defect repair, and it is widely used in the fabrication of semiconductor products such as integrated circuits, power devices, and optoelectronic devices. The principle of ion implantation is to ionize atoms or molecules to form plasma. Ions in the plasma carry a certain amount of charge and can be accelerated by an electric field, thereby controlling the ions to enter the wafer with a certain energy to achieve doping. The ribbon ion source in ion implantation equipment is often implemented through point source scanning or other methods.

[0003] In the semiconductor manufacturing field, pattern shaping is another emerging technology. It is used to optimize and correct lithography patterns, or, in the absence of advanced lithography machines (such as EUV), to reduce linewidth and adjust aperture through deposition and etching techniques (such as the Centura Sculpta model of Applied Materials). It requires a certain amount of energy of ribbon-shaped ions or planar ions to act tilted on the wafer to assist in etching the sides of the trenches on the wafer. It has high requirements for beam energy, incident angle and uniformity.

[0004] Currently, the ion sources for ion implantation mainly include indirect heated filament ion sources (IHC), inductively coupled plasma (ICP) sources, and microwave plasma sources. The ion sources for etching pattern shaping are mainly ICP ion sources. To achieve a uniform strip-shaped tilted ion beam, most of them have the following problems: (1) large equipment size; (2) poor plasma uniformity; (3) limited adjustment of ion beam extraction angle and low process flexibility.

[0005] Therefore, it is necessary to provide an ion source and ion beam tilting extraction device that can flexibly adjust the ion beam extraction angle and achieve better uniformity, in order to meet the development needs of semiconductor processes. Summary of the Invention

[0006] In view of this, the purpose of this invention is to provide an ion source and an ion beam tilting extraction device. By setting up a microwave main path and an ion beam extraction control component, microwave energy flows in a traveling wave state in the microwave main path, represented by a waveguide. It can be gradually and uniformly released into the plasma chamber through slots on the waveguide. The latter is uniformly introduced with working gas under a certain vacuum, and ionization occurs under the action of electron cyclotron oscillation. Under the action of the ion beam extraction control component, the tilting extraction of the ion beam is achieved. Its uniformity can be improved by adjusting the local electric field and the local airflow. By applying different voltages to the ion beam extraction control component, the extraction tilt angle can be dynamically changed. The microwave traveling wave cyclotron slotting method for generating plasma disclosed in this invention can generate multi-point sources, planar sources, and spherical sources, in addition to ribbon ion beam sources.

[0007] To achieve the above-mentioned technical effects, the technical solution of the present invention is as follows: An ion source and ion beam tilting extraction device include a microwave main circuit, a plasma chamber, a gas supply component, an ion beam extraction control component, and a power supply component. The microwave main circuit includes a microwave source, a waveguide, and a residual power absorption load. The microwave source, the waveguide, and the residual power absorption load are connected in sequence. The waveguide is connected to a plasma chamber, and multiple slots facing the plasma chamber are spaced apart on the waveguide. Sealing components are provided at the slots to allow microwave energy in the waveguide to couple into the plasma chamber. The residual power absorption load is used to absorb the residual microwave energy in the microwave main circuit, so that the microwaves in the waveguide are transmitted in a traveling wave state. An ion beam outlet is formed on the plasma chamber; The gas supply assembly is connected to the plasma chamber and is used to introduce working gas into the plasma chamber; The ion beam extraction control component is located at the ion beam exit point of the plasma chamber, and the power supply component is electrically connected to the ion beam extraction control component to provide an adjustable voltage for ion beam extraction and deflection.

[0008] Furthermore, the plasma chamber has a hollow rectangular structure, the ion beam outlet is located on the side wall of the plasma chamber and is elongated, and the ion beam extraction control component is an extraction deflection electrode group, which is located at the ion beam outlet and is used to extract the ion beam at an angle from the ion beam outlet to form a strip-shaped ion source.

[0009] Furthermore, the plasma chamber has a hollow rectangular structure; The waveguide is a U-shaped waveguide group, which includes two rectangular waveguides and a connecting waveguide. The two rectangular waveguides are respectively disposed on the upper and lower sides of the plasma chamber, and the connecting waveguide connects the two rectangular waveguides into a whole with a U-shaped rotating structure. The bottom of the rectangular waveguide located on the upper side of the plasma chamber has multiple slots, and the top of the rectangular waveguide located on the lower side of the plasma chamber has multiple slots; the input end of one of the rectangular waveguides is connected to the microwave source, and the output end of the other rectangular waveguide is connected to the residual power absorption load. And / or, the deflection electrode assembly includes an extraction electrode and at least one pair of deflection electrodes, the deflection electrodes being symmetrically disposed on the upper and lower sides of the ion beam extraction port.

[0010] Furthermore, the sealing assembly includes a first medium plate, a pressure plate, and a first sealing ring, wherein the first medium plate is made of quartz glass or ceramic plate, etc. The first dielectric plate is pressed against the slot by the pressure plate and the first sealing ring, and the pressure plate has a through hole corresponding to the first dielectric plate to achieve vacuum sealing of the plasma chamber and microwave unidirectional coupling of the microwave main circuit toward the plasma chamber; And / or, a water-cooled plate is also provided on the rectangular waveguide.

[0011] Furthermore, the pressure plate has a magnet placement groove on the side of the through hole, and a permanent magnet is installed in the magnet placement groove to provide a magnetic field to the plasma chamber.

[0012] Furthermore, an adjustment hole is provided on the sidewall of the rectangular waveguide corresponding to each slot, and a metal adjustment pin is inserted in the adjustment hole. The metal adjustment pin is used to independently change the length of at least one slot, thereby controlling the microwave energy coupled into the plasma cavity.

[0013] Furthermore, the plasma chamber is cylindrical, and the ion beam extraction outlet is formed at the bottom of the plasma chamber and is circular. The ion beam extraction control assembly includes at least one layer of grid, disposed at the ion beam extraction outlet, for extracting the ion beam from the outlet and forming a planar ion source. This type of tilted ion beam extraction is often achieved through structural misalignment between multiple grid layers and the application of a specific voltage. Furthermore, the waveguide is a tape measure-shaped waveguide with a tape measure-like path extending outward from a circular arc; the waveguide is disposed at the upper end of the plasma chamber, and microwave energy transmitted by the microwave source can be fed in along the outer end of the waveguide and transmitted towards the vicinity of the center along the tape measure-like path of the tape measure-shaped waveguide. The bottom of the waveguide has multiple slots along the tape measure-like path.

[0014] Furthermore, the sealing assembly includes a second dielectric plate and a second sealing ring; the size of the second dielectric plate is adapted to the diameter of the plasma chamber, and the second dielectric plate is sealed between the bottom of the tape measure-shaped waveguide and the top of the plasma chamber by the second sealing ring; the material of the second dielectric plate is quartz glass or ceramic plate, etc.

[0015] Furthermore, the gas supply assembly includes a first gas supply pipe, the input end of which is connected in series with a mass flow controller and a gas cylinder, and the output end extends into the plasma chamber and is sealed at the rear end. A plurality of gas outlet holes are spaced apart on the first gas supply pipe located in the plasma chamber. And / or, the gas supply assembly includes a plurality of second gas supply pipes, and a plurality of air inlets are spaced apart on the side wall of the plasma chamber. Each air inlet is connected to a second gas supply pipe, and the input end of the second gas supply pipe is connected to a mass flow controller, a gas path branch and a gas cylinder.

[0016] Furthermore, the first air supply pipe is provided with a plurality of air outlet holes at unequal intervals.

[0017] The beneficial effects of this invention are as follows: The ion source and ion beam tilting extraction device provided by this invention, through the arrangement of a microwave main path and an ion beam extraction control component, allows microwave energy to flow in a traveling wave state within the microwave main path, represented by a waveguide with a rotating structure. This energy is gradually and uniformly released into the plasma chamber through slots in the waveguide. The plasma chamber, under a certain vacuum, is uniformly supplied with working gas through a gas supply component, which ionizes under the action of electron cyclotron oscillation. Under the action of the ion beam extraction control component, uniform tilting extraction of the ion beam can be achieved. The uniformity can be further improved by adjusting the local electric field and the local airflow. By applying different voltages to the ion beam extraction control component, the extraction tilt angle can be dynamically changed, significantly improving the flexibility of the process. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this application or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other embodiments can be obtained based on these drawings.

[0019] Figure 1 This is a schematic diagram of the overall architecture of the present invention.

[0020] Figure 2This is a schematic diagram of the rear side of the ion source and ion beam tilting extraction device of the present invention.

[0021] Figure 3 This is a schematic diagram of the front structure of the ion source and ion beam tilting extraction device of the present invention.

[0022] Figure 4 This is a schematic diagram of the structure of the rectangular waveguide and sealing assembly in this invention.

[0023] Figure 5 This is a schematic diagram of the rectangular waveguide structure in this invention.

[0024] Figure 6 This is a schematic diagram of the pressure plate in this invention.

[0025] Figure 7 This is a schematic diagram of the application of the strip-shaped bundle to the wafer in this invention.

[0026] Figure 8 This is a schematic diagram of the structure of the present invention, which combines a tape measure-shaped waveguide to extract a planar ion source.

[0027] Explanation of reference numerals in the attached figures: 1. Microwave main path; 11. Microwave source; 12. Waveguide; 121. Slot; 122. U-shaped waveguide group; 1221. Rectangular waveguide; 1222. Connecting waveguide; 1223. Adjustment hole; 1224. Metal adjustment pin; 1225. First flange; 123. Measuring tape waveguide; 1231. Second flange; 13. Residual power absorbs the load; 2. Plasma chamber; 21. Ion beam exit point; 22. Gas inlet; 3. Air supply assembly; 31. First air supply pipe; 32. Air outlet; 33. Second air supply pipe; 4. Ion beam extraction and control assembly; 41. Deflection electrode; 42. Insulating support; 43. Grid; 5. Power supply assembly; 6. Sealing assembly; 61. First dielectric plate; 62. Pressure plate; 621. Through hole; 622. Magnet placement slot; 63. Second dielectric plate; 7. Water cooling plate; 10. Ion beam; 20. Wafer. Detailed Implementation

[0028] The structure provided by the present invention will be explained and described in detail below with reference to the accompanying drawings.

[0029] Example 1 refer to Figures 1 to 7As shown, this embodiment specifically discloses an ion source and an ion beam tilting extraction device, including a microwave main circuit 1, a plasma chamber 2, a gas supply component 3, an ion beam extraction control component 4, and a power supply component 5; The simplest microwave main circuit 1 includes a microwave source 11, a waveguide 12, and a residual power absorption load 13. The entire microwave main circuit 1 can operate in an atmospheric environment. A more complex microwave main circuit 1 can have a power circulator (not shown in the figure) or an isolator (not shown in the figure) connected in series after the microwave source 11. This absorbs the reflected microwave power generated thereafter, ensuring that no standing waves are formed in the waveguide 12. The microwave source 11 provides microwave energy to the microwave main circuit 1. Its frequency can be a commonly used industrial frequency such as 915MHz, 2450MHz, 5800MHz, or 24.125GHz, or a microwave source with a specially customized frequency. The power of the microwave source varies from 100 to 10000W, and it can be a continuous wave or a pulsed wave, which can be selected and set as needed.

[0030] Waveguide 12 is a waveguide with a rotation path, allowing it to pass through plasma chamber 2 at least twice. Microwave source 11, waveguide 12, and residual power absorption load 13 are connected in sequence. Waveguide 12 is connected to plasma chamber 2, and multiple slots 121 facing plasma chamber 2 are spaced apart on waveguide 12. Sealing components 6 are provided at slots 121 to couple microwave energy in waveguide 12 into plasma chamber 2. That is, sealing components 6 can couple microwave energy into plasma chamber 2, while sealing and isolating plasma chamber 2 from waveguide 12, preventing material exchange between plasma chamber 2 and waveguide 12 through slots 121, and ensuring vacuum in plasma chamber 2. Residual power absorption load 13 is used to absorb the remaining microwave energy in microwave main path 1, so that microwaves in waveguide 12 are transmitted in a traveling wave state. In this embodiment, the reason for maintaining the microwave traveling wave state is that once the microwave in the waveguide 12 forms a standing wave, the incident and reflected power superimposed, and the field strength in space will have a periodic high and low distribution, which in turn leads to uneven microwave energy penetrating into the plasma chamber 2, resulting in uneven plasma density and thus uneven beam spatial distribution. An ion beam outlet 21 is formed on the plasma chamber 2; The gas supply component 3 is connected to the plasma chamber 2 and is used to introduce working gas, such as inert gas (argon), reactive gas (fluorine, chlorine, carbon tetrafluoride), etc., into the plasma chamber 2, which is the gas source for forming plasma; the reactive gas can also be directly introduced into the process chamber where the wafer is located.

[0031] The ion beam extraction control component 4 is located at the ion beam extraction outlet 21 of the plasma chamber 2. The power supply component 5 is electrically connected to the ion beam extraction control component 4 according to the electrodes, and is used to provide an adjustable voltage for the extraction and deflection of the ion beam 10.

[0032] Specifically, waveguide 12 permeates a portion of the microwave power into plasma chamber 2 through a slot (slot 121). Plasma chamber 2 is in a vacuum system, and then working gas is introduced through gas supply component 3. When the vacuum level reaches the expected range (10... -3 When the microwave field penetrating the waveguide reaches a certain intensity (Pa~10Pa), the gas molecules will be ionized, generating plasma. The size of the slot 121 on the waveguide 12 can affect the plasma density in a local area, while ensuring that arcing does not occur in the main microwave path 1. The position and number of slots 121 on the waveguide 12 are determined according to the specific application requirements and the distribution of the surface current when the microwave propagates within the waveguide.

[0033] In some preferred embodiments, a static magnetic field can be provided by setting a permanent magnet. With the assistance of the applied static magnetic field, an electron cyclotron resonance (ECR) is generated in the plasma chamber 2, which further increases the probability of electrons colliding with gas molecules, and the plasma density can be further increased, eventually reaching a steady state.

[0034] It should be noted that even without the assistance of a static magnetic field, a slightly lower plasma density can still be generated. Therefore, the choice of whether to use a permanent magnet to generate a static magnetic field can be made based on specific requirements and difficulty.

[0035] The ion source and ion beam tilting extraction device provided in this embodiment, by setting up a microwave main path 1 and an ion beam extraction control component 4, allows microwave energy to flow in a traveling wave state in the microwave main path 1, represented by a waveguide 12 with a rotating structure. This energy is gradually and uniformly released into the plasma chamber 2 through slots 121 on the waveguide 12. The plasma chamber 2, under a certain vacuum, is uniformly supplied with working gas through a gas supply component 3. Ionization occurs under the action of electron cyclotron oscillation. Under the action of the ion beam extraction control component, tilting extraction of the ion beam can be achieved. Its uniformity can be further improved by adjusting the local electric field and the local airflow. By applying different voltages to the ion beam extraction control component 4, the extraction tilt angle can be dynamically changed, significantly improving the flexibility of the process.

[0036] Combination Figure 2-5As shown, in this embodiment, the plasma chamber 2 has a hollow rectangular structure, and the ion beam outlet 21 is located on the front side wall of the plasma chamber 2 and is elongated. During operation, the plasma chamber 2 and the vicinity of its outlet process space are first evacuated and then a specified flow rate of working gas is introduced (the boundary of the vacuum region is not shown in the figure).

[0037] The ion beam extraction control assembly 4 is an extraction deflection electrode group, specifically including extraction electrodes and at least one pair of deflection electrodes 41. The deflection electrodes 41 are symmetrically arranged on the upper and lower sides of the ion beam extraction outlet 21, and are specifically installed and fixed at the ion beam extraction outlet 21 of the plasma chamber 2 by an insulating support 42, which serves as an insulating isolation. The voltage applied between the extraction electrodes and the plasma chamber is negative or positive, which can extract positive or negative ions or electrons from the ion source. Correspondingly, the power supply assembly 5 includes an extraction power supply connected to the extraction electrode and a deflection power supply connected to the deflection electrode 41. The extraction power supply can be used to form an accelerating electric field between the extraction electrode and ground to control the emission energy of the ion beam. The deflection power supply can independently apply voltage to the two deflection electrodes 41. By adjusting the positive and negative values ​​and magnitudes of the voltage, different intensities of deflection electric fields can be formed to control the tilt extraction angle of the ion beam. The power supply assembly 5 can also integrate a voltage display, adjustment knob, and control module, supporting manual or automatic adjustment of voltage parameters to meet the precise requirements of different processes. The power supply can operate in a DC voltage state or in a specific pulse voltage state. Coordination and synchronization are required during adjustment.

[0038] The following example of extracting positive ions shows that positive ions can be extracted in (but not limited to) the following ways: The extraction electrode can be directly the target stage (the target stage on which the wafer is placed). The target stage is subjected to a negative voltage, so the extracted positive ions are accelerated under the action of the electric field; The extraction electrode can also be independent of the plasma chamber. Its material can be metal, metal-ceramic sandwich structure, or ceramic surface coated with metal film structure. The plasma chamber is grounded, and the extraction electrode and the target stage are simultaneously subjected to a negative voltage, forming an equipotential space between them. The deflection electrode 41 can also be arranged in this space. The positive ions are accelerated before entering this equipotential space; The extraction electrode can also be the equipotential cavity wall of the ion source chamber. They are subjected to a positive voltage. There is a deflection electrode 41 and a ground electrode between them and the target stage. The target stage and the ground electrode are both grounded. The electric field between the extraction electrode and the ground electrode accelerates the positive ions and extracts them from the slots and holes of the two. In this way, the ground electrode and the target stage present an equipotential space. The ions have basically no large directional deflection in a short distance and are only affected by the charge force of the surrounding space.

[0039] The deflection electrode 41 is also one of the electrodes in the ion beam extraction and control assembly. It applies an electric field from both sides of the strip beam to cause the strip beam to deflect as a whole. Each deflection electrode 41 is connected to the deflection power supply in the power supply assembly 5 to achieve rich beam deflection and beam divergence effects. The deflection electrode does not affect the final energy of ion emission.

[0040] This embodiment can achieve dynamic tilt angle extraction of the ribbon beam (defined as the angle between the normal of the ion source emission surface and the beam emission direction), with an angle range of 0° to 80°. The ion energy is determined by the extraction voltage in the power supply component to accelerate the ions, and the size of the ion beam is jointly determined by the plasma density inside the ion source and the extraction voltage.

[0041] Correspondingly, in this embodiment, waveguide 12 is a U-shaped waveguide assembly 122, which generally operates under atmospheric conditions. It includes two rectangular waveguides 1221 of the same specifications and a connecting waveguide 1222. The two rectangular waveguides 1221 are respectively arranged on the upper and lower sides of the plasma chamber 2. The connecting waveguide 1222 connects the two rectangular waveguides 1221 into a whole with a U-shaped rotation structure. The connecting waveguide 1222 can be a bent waveguide or a coaxial waveguide adapter, and can be connected and fixed through the first flange 1225 during connection. At this time, the microwave main path is U-shaped, and the U-shaped rotation itself has almost no impact on the traveling wave transmission of microwave energy. The bottom of the rectangular waveguide 1221 located on the upper side of the plasma chamber 2 is provided with multiple slots 121, and the top of the rectangular waveguide 1221 located on the lower side of the plasma chamber 2 is provided with multiple slots 121; the input end of one rectangular waveguide 1221 is connected to the microwave source 11, and the output end of the other rectangular waveguide 1221 is connected to the residual power absorption load 13. The microwave main path is a U-shaped traveling wave flowing in the waveguide. The microwave reflection caused by the waveguide slot is minimal. Even if there is reflection, it is absorbed by the microwave source (which often has its own isolator) and the residual power absorption load 13, and does not affect the traveling wave state on the microwave main path.

[0042] In this embodiment, as the microwave travels along the U-shaped main path, energy continuously permeates into the plasma chamber 2 through the slot 121. The microwave power continuously attenuates along the main path, but due to the back-and-forth movement, the combined effect of energy leakage from the upper and lower slots on any part of the plasma in the plasma chamber 2 is essentially the same, ensuring basic plasma uniformity. Without loss of generality, to ensure uniform etching on the 12-inch wafer, the length of the ion beam exit 21 on the plasma chamber 2 is 350mm to 500mm, ensuring sufficient margin on both sides.

[0043] Because some of the microwave energy will eventually be consumed inside the device as a temperature rise, which can cause slight structural deformation and possible demagnetization of permanent magnets, thus affecting the beam state, in some preferred embodiments, water-cooled plates 7 are also provided on the outer surfaces of the two rectangular waveguides 1221. The cooling medium in the water-cooled plates 7 is in direct or indirect contact with the rectangular waveguides 1221 to keep the temperature of the U-shaped waveguide group 122 constant.

[0044] Continue to refer to Figure 2 and Figure 3 In this embodiment, the gas supply component 3 includes a first gas supply pipe 31. The input end of the first gas supply pipe 31 is connected in series with a mass flow controller and a gas cylinder (containing working gas). The output end extends into the plasma chamber 2 and is sealed at the end. Several gas outlet holes 32 are spaced apart on the first gas supply pipe 31 located in the plasma chamber 2. This is the first ventilation method. Because more gas will flow out from the first small hole, in order to further ensure the uniformity of gas supply, the gas outlet holes 32 can be opened at unequal intervals on the first gas supply pipe 31. The size of the holes and the degree of unequal intervals can be obtained by simulation optimization using fluid software to ensure that the gas is uniformly diffused in the plasma chamber 2. A mass flow controller is set on the first gas supply pipe 31 before entering the plasma chamber 2 to control and regulate the airflow.

[0045] In some other embodiments, the gas supply assembly 3 includes multiple second gas supply pipes 33, and multiple air inlets 22 are spaced apart on the rear side wall of the plasma chamber 2. Each air inlet 22 is connected to a second gas supply pipe 33, and the input end of the second gas supply pipe 33 is connected to a gas cylinder. This is the second type of ventilation. In this case, a mass flow controller can be installed at the front end of each second gas supply pipe 33 and connected to a gas cylinder through a branch gas path. This provides sufficient means to adjust the uniformity of the gas jet distribution.

[0046] Combination Figure 4-6 In this embodiment, a plurality of slots 121 are formed on the rectangular waveguide 1221 along its width direction. The size and position of these slots 121 are designed to cut off the surface current on the inner surface of the waveguide, so that a large amount of radiation will be radiated from the waveguide into the plasma chamber 2. At this time, a sealing component 6 is installed at each slot 121. The sealing component 6 includes a first dielectric plate 61, a pressure plate 62 and a first sealing ring. The material of the first dielectric plate 61 is sufficient to ensure that microwave energy is fed into the plasma chamber 2. Specifically, it can be quartz glass, alumina ceramic, yttrium oxide ceramic, etc. The first dielectric plate 61 is pressed against the slot 121 by the pressure plate 62 and the first sealing ring. The pressure plate 62 has a through hole 621 corresponding to the first dielectric plate 61, realizing the vacuum sealing state of the plasma chamber 2 and the unidirectional microwave coupling of the microwave main circuit 1 towards the plasma chamber 2. This ensures that the inside of the waveguide operates under atmospheric conditions while the inside of the plasma chamber 2 operates under a vacuum, and also avoids large microwave power reflection on the main circuit caused by arcing inside the waveguide.

[0047] In some preferred embodiments, the pressure plate 62 has magnet placement slots 622 on the left and right sides of the through hole 621. When the ECR requires a static magnetic field with a certain magnetic induction intensity, a permanent magnet with a designed magnetization direction and size can be placed here to enhance the local plasma density.

[0048] Continue to refer to Figure 4 and Figure 5 In this embodiment, an adjustment hole 1223 is provided on the sidewall of the rectangular waveguide 1221 corresponding to each slot 121. A metal adjustment pin 1224 is inserted into the adjustment hole 1223. The metal adjustment pin 1224 can be a metal screw or a metal pin. The metal adjustment pin 1224 is used to independently change the length of at least one slot 121 (i.e., to achieve one-dimensional line segment movement in the adjustment hole 1223), thereby controlling the microwave energy coupled into the plasma chamber 2; thus controlling the local plasma density. Two rows of slow electrodes (not shown in the figure) can be set in the atmosphere to regulate these metal adjustment pins 1224, which can automatically control the plasma distribution and assist in homogenizing the extracted ion beam.

[0049] Combination Figure 7The diagram illustrates a simplified representation of the strip beam of ions applied to wafer 20 and the target stage (used to hold the wafer). Various beam extraction methods exist; here, the extraction voltage acts directly between the target stage and the ion source. Positive and negative voltages (within the absolute values) are applied to a pair of metal deflection electrodes 41. This creates a non-equipotential space where the ion beam 10 exhibits a curved trajectory, with ions carrying energy acting on wafer 20 at a specific angle. This angle depends on the sign and magnitude of the deflection voltage on the deflection electrodes 41, the magnitude of the extraction voltage between the target stage and the ion source, and the distance between them. Due to the influence of the electric field and space charge force, the ion beam exhibits a gradually diverging trend, described by the ion angular distribution (IAD). The IAD can also be controlled by the relative magnitude of the deflection voltage on the pair of deflection electrodes 41. Thus, in practical applications, the angle of the strip beam and the IAD can be dynamically adjusted without structural movement, providing more flexible options for wafer processing. For those familiar with the field, employing a multi-electrode extraction structure to create an equipotential space in the ion flight region is feasible and common. The metal deflection electrodes 41 can also be of other shapes, sizes, and numbers; combined with beam simulation software (COMSOL, CST, etc.), the electric field morphology can be altered to adjust the direction of the ion beam 10.

[0050] In this embodiment, the generation of a ribbon ion source and the tilted extraction of the ion beam are achieved through the synergistic effect of microwave traveling wave feeding ionization, uniform gas feeding, and electric field-controlled ion beam extraction and deflection. The coordinated movement of each component and the energy transfer process are as follows: (1) Vacuum environment establishment: Start the vacuum system of plasma chamber 2 to pump the vacuum level in plasma chamber 2 and the ion beam extraction area to the required process preset range, so as to provide vacuum conditions for gas ionization; (2) Working gas feed: Start the gas supply assembly 3 and feed the basic working gas into the plasma chamber 2 through the first gas supply pipe 31 and / or the second gas supply pipe 33 to achieve uniform gas distribution in the chamber. (3) Microwave traveling wave transmission and feeding: Start the microwave source 11 and output microwave energy with preset power. The microwave energy enters the input end of the U-shaped waveguide group 122 through the flange and is transmitted in the form of a traveling wave in the two rectangular waveguides 1221 along the U-shaped rotation path. During the transmission process, the microwave energy passes through the first dielectric plate 61 through each slot 121 and is fed into the plasma chamber 2 in one direction. The remaining microwave energy is completely absorbed by the remaining power absorption load 13 to ensure that there are no reflected microwaves in the U-shaped waveguide group 122 and avoid the formation of standing waves. (4) Plasma generation and uniformity control: In the plasma chamber 2, the coupled microwave energy, with the assistance of the local static magnetic field provided by the permanent magnet (or without setting a static magnetic field), realizes electron cyclotron resonance. The electrons collide with the working gas molecules at high frequency, causing the gas molecules to ionize and form plasma. If the plasma density distribution is uneven, the effective radiation length of the corresponding slot 121 can be changed by independently turning the metal adjusting nail 1224, thereby adjusting the microwave coupling at that position and controlling the local plasma density in the plasma chamber 2 to achieve the optimization of the uniformity of the overall plasma density. The water-cooled plate 7 continuously circulates cooling water during microwave transmission to remove the waveguide heat and ensure the stability of microwave energy transmission. (5) Ion beam extraction and tilting deflection: Start the power supply component 5, apply a preset acceleration voltage to the power supply, and form an acceleration electric field between the extraction electrode and the ground. Accelerate the positive ions in the plasma along the direction of the electric field (in the pulse working state, positive ions, negative ions or electrons can be extracted alternately) and be extracted from the long strip-shaped ion beam extraction outlet 21 to form a strip-shaped ion beam. At the same time, according to the ion beam tilt angle required by the process, apply positive and negative voltages to the deflection electrodes 41 on the upper and lower sides of the ion beam extraction outlet 21 through two independent deflection power supplies to form a deflection electric field on the ion beam emission path. When the strip-shaped ion beam passes through the deflection electric field, it undergoes curved motion under the action of the electric field force and is emitted at a preset tilt angle of 0°~80° to realize the tilting extraction of the ion beam. (6) Parameter dynamic control: During the process, the plasma density can be dynamically controlled by adjusting the output power of the microwave source 11 and the position of the metal adjustment pin 1224, thereby changing the beam current of the extracted ion beam; the output energy of the ion beam can be changed by adjusting the voltage of the extraction power supply; the tilt extraction angle and angular divergence of the ion beam can be controlled in real time by adjusting the positive and negative voltage and magnitude of the deflection electrode 41. Without changing the mechanical structure, the pure electric dynamic control of the ion beam parameters can be achieved, which meets the anisotropic requirements of semiconductor process.

[0051] Example 2 refer to Figure 8 As shown in the figure, this embodiment is a schematic diagram of the result of extracting a planar ion source. The plasma chamber 2 is cylindrical, and the ion beam outlet 21 is formed at the bottom of the plasma chamber 2 and is circular. The ion beam extraction control component 4 includes at least one layer of grid 43, which is disposed at the ion beam outlet 21 and is used to extract the ion beam from the ion beam outlet 21 and form a planar ion source.

[0052] Specifically, such as Figure 8As shown, in this embodiment, waveguide 12 is a tape measure-shaped waveguide 123, which has a tape measure-like path extending outward from a circumferential arc. A second flange 1231 is provided at the outermost input end of the tape measure-shaped waveguide 123. Waveguide 12 is located at the upper end of plasma chamber 2. Microwave energy transmitted through microwave source 11 can be fed in along the second flange 1231 at the outer end of waveguide 12 and transmitted towards the vicinity of the center along the tape measure-like path of the tape measure-shaped waveguide 123. Then, it can be fed out to the residual power absorption load 13 (in the coaxial waveguide adapter and coaxial cable) through a coaxial waveguide adapter and coaxial cable. Figure 8 (Not shown in the text); Similarly, the microwaves in the tape measure-shaped waveguide 123 are in a traveling wave state to avoid forming standing waves, so as to ensure the uniformity of the formed ion source. Multiple slots 121 are formed along a tape measure-like path at the bottom of waveguide 12. The current in the cut surface inside waveguide 12 causes microwave energy to permeate out. The number of tape measure layers, the number, distribution, and size of the slots 121 can be designed and optimized in detail using electromagnetic field software (HFSS, COMSOL, CST, etc.). The microwave energy attenuates continuously as it travels, and combined with the slot distribution, this allows for uniform microwave energy penetration across the entire circular surface.

[0053] In this embodiment, since there are too many slots 121, it is not suitable to dynamically adjust the length of each slot 121 individually. Instead, they are all coupled to the plasma chamber 2 through an insulating medium.

[0054] That is, in this embodiment, the sealing assembly 6 includes a second dielectric plate 63 and a second sealing ring; the size of the second dielectric plate 63 is adapted to the diameter of the plasma chamber 2, and the second dielectric plate 63 is sealed between the bottom of the tape measure-shaped waveguide 123 and the top of the plasma chamber 2 by the second sealing ring.

[0055] The second dielectric plate 63 and the second sealing ring ensure that the plasma chamber 2 operates normally in the vacuum system without obstructing microwave penetration into the plasma chamber 2. The second dielectric plate 63 can be made of quartz glass, alumina ceramic, yttrium oxide ceramic, etc. In PE (Plasma Etching) equipment, the target stage and wafer can be designed to be transported into the plasma chamber 2 for processing. In IBE (Ion Beam Etching) or RIE (Reactive Ion Etching) equipment, the ion beam is extracted from a grid hole on one side of the plasma chamber 2. The grid 43 can be a single-layer, double-layer, triple-layer, or multi-layer grid to achieve acceleration, deflection, and grounding to create an equipotential space. The target stage and wafer 20 can be designed to be transported below the grid to receive the ion beam for processing. To increase the ECR ionization effect, a current-carrying coil can be placed outside the plasma chamber 2 to generate a static magnetic field, provided that this static magnetic field does not have an additional impact on the extracted beam.

[0056] The present invention has the following technical effects: (1) Regardless of whether it is a 6-inch, 8-inch, or 12-inch wafer, the strip beam source and the planar source described in this invention can be easily scaled up. For the strip beam source, only the length of the rectangular waveguide and the plasma chamber needs to be adjusted; for the planar source, only the number of layers of the tape measure waveguide and the diameter of the plasma chamber need to be adjusted.

[0057] (2) The plasma density generated by microwave ECR is no weaker than that generated by ICP, but it exhibits the characteristics of smaller volume, easier uniformity adjustment, easier heat dissipation under high power, and fewer electromagnetic compatibility problems caused by energy leakage. The plasma generated by traveling wave avoids the natural non-uniformity of plasma generated by standing wave in the prior art.

[0058] (3) The tilt angle and IAD of the ion beam are dynamically controlled by deflection electrodes, which greatly improves the flexibility of the process compared with the fixed method in the prior art.

[0059] (4) Compared with the microwave electronic source (MPEF: Microwave Plasma Electron Flood) commonly used in semiconductor equipment, the microwave main path and plasma region of the present invention are physically separated. The microwave energy is uniformly and slowly released into the plasma region, and the plasma is restricted to enter the microwave main path to achieve unidirectional coupling, which can prevent abnormal arcing inside the waveguide.

[0060] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0061] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0062] In the description of this specification, the references to terms such as "this embodiment," "an embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the present invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any at least one embodiment or example. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0063] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0064] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and simple improvements made on the substantive content of the present invention should be included within the protection scope of the present invention.

Claims

1. An ion source and an ion beam tilting extraction device, characterized in that, It includes a microwave main circuit (1), a plasma chamber (2), a gas supply assembly (3), an ion beam extraction and control assembly (4), and a power supply assembly (5). The microwave main path (1) includes a microwave source (11), a waveguide (12), and a residual power absorption load (13). The waveguide (12) is a waveguide with a rotation path, so that the waveguide (12) passes through the plasma chamber (2) at least twice. The microwave source (11), the waveguide (12), and the residual power absorption load (13) are connected in sequence. The waveguide (12) is connected to the plasma chamber (2), and a plurality of slots (121) facing the plasma chamber (2) are spaced apart on the waveguide (12). A sealing component (6) is provided at the slot (121) to allow the microwave energy in the waveguide (12) to be coupled to the plasma chamber (2). The residual power absorption load (13) is used to absorb the residual microwave energy in the microwave main path (1), so that the microwave in the waveguide (12) is transmitted in a traveling wave state. An ion beam outlet (21) is formed on the plasma chamber (2). The gas supply assembly (3) is connected to the plasma chamber (2) and is used to introduce working gas into the plasma chamber (2); The ion beam extraction control component (4) is located at the ion beam outlet (21) of the plasma chamber (2). The power supply component (5) is electrically connected to the ion beam extraction control component (4) and is used to provide an adjustable voltage for the extraction and deflection of the ion beam (10).

2. The ion source and ion beam tilting extraction device according to claim 1, characterized in that, The plasma chamber (2) has a hollow rectangular structure. The ion beam outlet (21) is located on the side wall of the plasma chamber (2) and is long and narrow. The ion beam extraction control component (4) is an extraction deflection electrode group, which is located at the ion beam outlet (21) and is used to extract the ion beam from the ion beam outlet (21) and form a strip-shaped ion source.

3. The ion source and ion beam tilting extraction device according to claim 2, characterized in that, The waveguide (12) is a U-shaped waveguide group (122), which includes two rectangular waveguides (1221) and a connecting waveguide (1222). The two rectangular waveguides (1221) are respectively disposed on the upper and lower sides of the plasma chamber (2). The connecting waveguide (1222) connects the two rectangular waveguides (1221) into a whole with a U-shaped rotating structure. The bottom of the rectangular waveguide (1221) located on the upper side of the plasma chamber (2) is provided with a plurality of slots (121), and the top of the rectangular waveguide (1221) located on the lower side of the plasma chamber (2) is provided with a plurality of slots (121); the input end of one of the rectangular waveguides (1221) is connected to the microwave source (11), and the output end of the other rectangular waveguide (1221) is connected to the residual power absorption load (13); And / or, the deflection electrode group includes an extraction electrode and at least one pair of deflection electrodes (41), the deflection electrodes (41) being symmetrically disposed on the upper and lower sides of the ion beam extraction port (21).

4. The ion source and ion beam tilting extraction device according to claim 3, characterized in that, The sealing assembly (6) includes a first medium plate (61), a pressure plate (62) and a first sealing ring. The first medium plate (61) is made of quartz glass or ceramic plate. The first dielectric plate (61) is pressed against the slot (121) by the pressure plate (62) and the first sealing ring, and the pressure plate (62) has a through hole (621) corresponding to the first dielectric plate (61) to achieve vacuum sealing of the plasma chamber (2) and microwave unidirectional coupling of the microwave main circuit (1) toward the plasma chamber (2); And / or, a water-cooled plate (7) is also provided on the rectangular waveguide (1221).

5. The ion source and ion beam tilting extraction device according to claim 4, characterized in that, The pressure plate (62) has a magnet placement groove (622) on the side of the through hole (621), and a permanent magnet is provided in the magnet placement groove (622) to provide a magnetic field to the plasma chamber (2).

6. The ion source and ion beam tilting extraction device according to claim 3, characterized in that, An adjustment hole (1223) is provided on the side wall of the rectangular waveguide (1221) for each slot (121). A metal adjustment pin (1224) is inserted in the adjustment hole (1223). The metal adjustment pin (1224) is used to independently change the length of at least one slot (121) to control the microwave energy coupled to the plasma chamber (2).

7. The ion source and ion beam tilting extraction device according to claim 1, characterized in that, The plasma chamber (2) is cylindrical, and the ion beam outlet (21) is formed at the bottom of the plasma chamber (2) and is circular. The ion beam extraction control component (4) includes at least one layer of grid (43) and is disposed at the ion beam outlet (21) for extracting from the ion beam outlet (21) and forming a planar ion source.

8. The ion source and ion beam tilting extraction device according to claim 7, characterized in that, The waveguide (12) is a tape measure-shaped waveguide (123) with a tape measure-shaped path extending outward from the circumferential arc; the waveguide (12) is located at the upper end of the plasma chamber (2), and the microwave energy transmitted by the microwave source (11) can be fed in along the outer end of the waveguide (12) and transmitted towards the vicinity of the center along the tape measure-shaped path of the tape measure-shaped waveguide (123); The bottom of the waveguide (12) has a plurality of slots (121) along the tape measure-like path.

9. The ion source and ion beam tilting extraction device according to claim 8, characterized in that, The sealing assembly (6) includes a second dielectric plate (63) and a second sealing ring; the size of the second dielectric plate (63) is adapted to the diameter of the plasma chamber (2), and the second dielectric plate (63) is sealed between the bottom of the tape measure waveguide (123) and the top of the plasma chamber (2) by the second sealing ring; the material of the second dielectric plate (63) is quartz glass or ceramic plate.

10. The ion source and ion beam tilting extraction device according to any one of claims 1-9, characterized in that, The gas supply assembly (3) includes a first gas supply pipe (31). The input end of the first gas supply pipe (31) is connected in series with the mass flow controller and the gas cylinder. The output end extends into the plasma chamber (2) and is sealed at the end. A plurality of gas outlet holes (32) are spaced apart on the first gas supply pipe (31) located in the plasma chamber (2). And / or, the gas supply assembly (3) includes a plurality of second gas supply pipes (33), and a plurality of air inlets (22) are spaced apart on the side wall of the plasma chamber (2). Each air inlet (22) is connected to a second gas supply pipe (33), and the input end of the second gas supply pipe (33) is connected to a mass flow controller, a gas path branch and a gas cylinder.

11. The ion source and ion beam tilting extraction device according to claim 10, characterized in that, The first air supply pipe (31) has a plurality of air outlet holes (32) spaced at unequal intervals.

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