etching aluminum nitride or aluminum oxide to produce a beam of aluminum ions

Abstract

An ion implantation system 101, ion source 108, and method are provided in which the ion source is configured to ionize an aluminum-based ion source material 113, 112 and form an ion beam 112 and byproducts including non-conductive materials. The etchant gas mixture has a predetermined content of fluorine and a noble gas in fluid communication with the ion source. The predetermined content of fluorine is associated with a predetermined health and safety level, such as about 20% of a maximum content of fluorine. The etchant gas mixture can have a co-incident gas of argon with a content of less than about 5%. The aluminum-based ion source material can be a ceramic component, such as a repeller shaft, a shield, or other component within the ion source.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Application No. 63 / 107,769, filed October 30, 2020, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates generally to ion implantation systems, and more specifically to an ion implantation system configured to generate an ion beam comprising aluminum ions. Background Technology

[0004] The demand for ion-implanted products using metal ions is increasing. For example, aluminum-implanted products are important for the power device market, a small but rapidly growing segment. Providing feed to the ion source presents challenges for various metals, including aluminum. Systems using evaporators—small ovens located outside the arc cavity of the ion source—have been previously provided to heat metal salts to generate sufficient vapor pressure to supply vapor to the ion source. However, the oven is located far from the arc cavity and requires time to heat to the required temperature, establish vapor flow, initiate plasma, and start the ion beam. Furthermore, if a change of metal species is required, time is needed for the oven to cool sufficiently before such a change can occur.

[0005] Another conventional technique involves placing a metallic material (such as aluminum or other metals) within the arc cavity. For aluminum, the metallic material can include alumina, aluminum fluoride, or aluminum nitride, all of which can withstand the approximately 800°C temperature of the plasma cavity. In such a system, ions are sputtered directly from the material within the plasma. Another technique uses plasma containing an etchant (such as fluorine) to achieve chemical etching of the metal. While acceptable beam currents can be achieved using these various techniques, compounds of alumina, aluminum chloride, and aluminum nitride (all of which are good electrical insulators) tend to deposit on the electrodes adjacent to the ion source within a relatively short timeframe (e.g., 5–10 hours). This results in various detrimental effects, such as high voltage instability and associated variations in the injected ion dose. Summary of the Invention

[0006] Therefore, this disclosure provides systems and apparatus for generating ion beams comprising aluminum ions. Accordingly, a simplified overview of this disclosure is provided below to provide a basic understanding of some aspects of the invention. This overview is not a broad summary of the invention. It is neither intended to identify essential or key elements of the invention nor to describe the scope of the invention. Its purpose is to introduce some concepts of the invention in a simplified form as a prelude to the more detailed description that follows.

[0007] According to one aspect of this disclosure, an ion implantation system is provided, wherein an ion source is configured to ionize an aluminum-based ion source material and thereby form an ion beam. In one embodiment, the aluminum-based ion source material includes a ceramic component, wherein the ceramic component includes one or more of a repulsive pole axis, a shield, or a component within the ion source.

[0008] The ionization of the aluminum-based ion source material, for example, further forms byproducts including non-conductive materials. An etchant gas mixture is also in fluid communication with the ion source, wherein the etchant gas mixture includes a predetermined amount of fluorine and rare gases. The beam assembly is further configured to selectively deliver the ion beam to a terminal station for ion implantation into a workpiece. A vacuum system, for example, may be configured to substantially evacuate the ion source.

[0009] According to one embodiment, the rare gas includes one or more of helium and argon, wherein a predetermined content of fluorine is associated with a predetermined health and safety level. In one embodiment, the predetermined health and safety level is 20% of the maximum fluorine content. In another embodiment, the etchant gas mixture includes a pressurized gas source comprising ≤20% of an unreacted mixture of fluorine and helium. The pressurized gas source may also include a co-entraining gas. The co-entraining gas, for example, may include argon at a content of less than 5%. In another embodiment, the etchant gas mixture may include a co-entraining gas.

[0010] The etchant gas mixture, for example, is premixed within a pressurized bottle and comprises fluorine with one or more of argon and helium. In one embodiment, the container comprises about 20% or less fluorine. In another embodiment, the pressurized bottle also comprises less than about 5% argon.

[0011] According to another exemplary aspect of this disclosure, an ion implantation system is provided, wherein an ion source is configured to ionize an aluminum-based source material and thereby form an ion beam. The ionization of the aluminum-based source material further forms byproducts comprising non-conductive materials. An etchant gas supply is further provided, comprising an etchant gas mixture of fluorine and a rare gas, wherein the etchant gas supply is configured to introduce the etchant gas mixture into the ion source, wherein the fluorine is mixed with the rare gas at a health-safe level. A beam assembly selectively delivers the ion beam to a terminal station configured to receive the ion beam for ion implantation into a workpiece.

[0012] In one embodiment, the etchant gas mixture further includes a co-occurring gas. The co-occurring gas, for example, includes argon, such as argon at a concentration of less than 5%. The etchant gas supply may, for example, include a pressurized gas source. The pressurized gas source may, for example, include a pressurized bottle containing the etchant gas mixture. The etchant gas mixture may, for example, be provided in a premixed form in a container, such as a pressurized bottle containing a mixture of fluorine with one or more of argon and helium. The container may, for example, contain about 20% or less fluorine.

[0013] According to another exemplary aspect of this disclosure, a method for implanting aluminum ions into a workpiece is provided. The method, for example, includes providing an aluminum-based source material to an ion source and providing an etchant gas mixture to the ion source, wherein the etchant gas mixture includes a predetermined amount of fluorine and a rare gas. The predetermined amount of fluorine is, for example, less than about 20%. In one embodiment, the aluminum-based source material comprises a ceramic component. The rare gas may, for example, include one or more of argon and helium. The aluminum-based source material is ionized in the ion source, wherein fluorine etches the aluminum-based source material to generate aluminum ions. Furthermore, aluminum ions are implanted from the ionized aluminum-based source material into the workpiece.

[0014] In another embodiment, providing the etchant gas mixture to the ion source further includes providing a companion gas (e.g., argon) to the ion source. In another embodiment, the method further includes premixing the etchant gas in a container (e.g., a pressurized bottle containing fluorine with one or more of argon and helium). The container, for example, contains about 20% fluorine. In another embodiment, the container contains less than about 5% argon.

[0015] To achieve the foregoing and related objectives, this disclosure includes the features fully described and particularly pointed out in the claims. The following description and the accompanying drawings illustrate certain illustrative embodiments of the invention in detail. However, these embodiments indicate several of a variety of ways in which the principles of the invention can be employed. Other objects, advantages, and novel features of the invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings. Attached Figure Description

[0016] Figure 1 This is a block diagram of an exemplary vacuum system using aluminum-based ion source materials according to several aspects of this disclosure.

[0017] Figure 2 An exemplary method for ion implantation into a workpiece using an aluminum-based ion source material is shown. Detailed Implementation

[0018] This disclosure relates generally to ion implantation systems and related ion source materials. More specifically, this disclosure relates to components used in said ion implantation systems that utilize aluminum-based solid source materials to generate atomic ions at a range of temperatures (up to 1000°C) to electrically dope silicon, silicon carbide, or other semiconductor substrates. Furthermore, when using a premixed etchant gas comprising a predetermined mixture of fluorine and a rare or inert gas (e.g., helium), this disclosure minimizes various deposits on the extraction electrodes and source cavity components. This disclosure reduces source operating pressure, increases etching rates, and minimizes the sputtering rate of aluminum-containing materials, which will further improve overall lifetime and aluminum ion beam current.

[0019] Therefore, the invention will now be described with reference to the accompanying drawings, wherein the same reference numerals may be used to refer to the same elements throughout. It should be understood that the description of these aspects is illustrative only and should not be construed as limiting. In the following description, several specific details are set forth for purposes of explanation to provide a thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention may be practiced without these specific details. Furthermore, the scope of the invention is not intended to be limited by the embodiments or examples described below with reference to the accompanying drawings, but is intended to be limited only by the appended claims and their equivalents.

[0020] It should also be noted that the accompanying drawings are provided to illustrate certain aspects of embodiments of this disclosure and should therefore be considered exemplary only. In particular, the elements shown in the drawings are not necessarily to scale, and the arrangement of the various elements in the drawings is chosen to provide a clear understanding of the respective embodiments and should not be construed as necessarily representing the actual relative positions of the components in an implementation of an embodiment according to the invention. Furthermore, unless otherwise specifically stated, the features of the various embodiments and examples described herein can be combined with each other.

[0021] It should also be understood that any direct connection or coupling between the functional modules, devices, components, circuit elements, or other physical or functional units shown in the figures or described herein may also be implemented via indirect connection or coupling. Furthermore, it should be noted that the functional modules or units shown in the figures may be implemented as separate features or circuits in one embodiment, while in another embodiment they may or alternatively be implemented as common features or circuits, wholly or partially. For example, several functional modules may be implemented as software running on a common processor (e.g., a signal processor). It should further be understood that, unless otherwise stated, any connection described below as wire-based may also be implemented as wireless communication.

[0022] Ion implantation is a physical process used in semiconductor device fabrication to selectively implant dopants into semiconductor and / or wafer materials. Therefore, the implantation behavior is independent of the chemical interaction between the dopant and the semiconductor material. In ion implantation, dopant atoms / molecules from an ion source in an ion implanter are ionized, accelerated, form an ion beam, analyzed, and swept across or translated through the wafer by the ion beam. Dopant ions physically bombard the wafer, penetrate the surface, and stop below the surface at a depth relevant to their energy.

[0023] The ion source in an ion implanter typically generates an ion beam by ionizing source material in an arc cavity, where the source material is composed of the desired dopant element. The desired dopant element is then extracted from the ionized source material in the form of an ion beam.

[0024] Typically, when aluminum ions are the desired dopant element, materials such as aluminum nitride (AlN) and aluminum oxide (Al2O3) are used as source materials for aluminum ions for ion implantation purposes. Aluminum nitride or aluminum oxide is a solid insulating material, which is usually placed in the arc cavity (ion source) that forms the plasma.

[0025] A gas (e.g., fluorine) is introduced to chemically etch the aluminum-containing material, thereby ionizing the source material, and the aluminum is drawn out and transferred along the beamline to the workpiece (e.g., silicon carbide) located at the terminal station for injection. The aluminum-containing material, for example, is typically used as the source material for aluminum ions, in conjunction with some form of fluorine-based etchant gas (e.g., BF3, PF3, NF3, SiF4, SF6, etc.) in the arc cavity. However, these materials have the undesirable side effect of producing insulating materials (e.g., AlN, Al2O3, AlF3, etc.) that are expelled from the arc cavity along with the desired aluminum ions.

[0026] Insulating material is then applied to the components of the ion source, such as the lead-out electrodes, which then begin to build up charge and adversely alter the electrostatic properties of the lead-out electrodes. The result of this charge buildup is a behavior of the lead-out electrodes commonly referred to as arcing or "glitching," caused by the accumulated charge arcing with other components or grounding.

[0027] In extreme cases, the power supply behavior of the extraction electrodes can be altered or distorted. This often leads to unpredictable beam behavior, resulting in reduced beam current and frequent preventative maintenance to clean components associated with the ion source. Furthermore, debris and other residues from these materials can form in the arc cavity, thus altering its operating characteristics and requiring additional, frequent cleaning.

[0028] Furthermore, when using BF3, there are concerns, for example, that air leaks in the gas delivery system can lead to the formation of BO (AMU 27), which has the same mass as aluminum (AMU 27), allowing BO to be implanted along with the desired aluminum ions. When using BF3 as an etchant, for example, it has been observed that boron-containing lead-out electrode optical layers can subsequently delaminate and cause arcing between the electrode and the arc cavity slit, thus destabilizing the tool for production. Using NF3 can also present problems, for example, as the mass of nitrogen molecule+ (AMU 28) is close to that of aluminum+ (AMU 27) and can potentially cause implantation energy contamination through mass-resolved systems. Similar concerns exist for atomic nitrogen and doubly charged aluminum (Al++ has mass / charge ratios of 14 and 13.5, respectively), which have similar mass-to-charge ratios. Furthermore, it has been observed that using such molecules reduces the ability to obtain the desired aluminum beam current, particularly for multi-charged ions.

[0029] Therefore, this disclosure aims to minimize deposits on the extraction electrodes and other components associated with the ion source cavity while providing the required beam current during aluminum ion implantation. This disclosure advantageously reduces formation-related minor faults or arcing and further extends the overall lifetime of the ion source and electrodes, while improving efficiency.

[0030] According to one exemplary aspect of this disclosure, an aluminum-based sputtering / etching target is provided together with an etchant source gas. The etchant source gas is advantageously provided in a premixed form in a container (e.g., a gas cylinder) containing helium (He) and a predetermined percentage of fluorine (F2) to allow for a lower total gas flow than conventional systems, while providing lower arc cavity pressure and further reducing secondary collisions (e.g., charge exchange), attributed to the smaller ionization cross-section of helium compared to other conventional fluorine-containing molecules and mixtures.

[0031] The inventors have observed that the total extraction current can be reduced by >20% for the required aluminum beam current because fluorine donor atoms (e.g., boron, phosphorus, silicon) are not ionized and extracted. Helium has the highest first ionization energy of 24.57 ppm, and its contribution to the total extraction current is negligible. The reduction in extraction current also reduces the pressure between the arc cavity optics and the extraction electrodes, and decreases the arc between the two surfaces. This is beneficial for improving beam stability because, as previously mentioned, the extraction electrodes will be covered with insulating material over time. This disclosure notes that in some cases, based on operating conditions or the required injector, it is preferable to use a mixture of a rare or inert gas other than helium premixed with a predetermined percentage of fluorine. For example, in cases where sputtering aluminum-based ceramics is required, argon (Ar) can be premixed with fluorine and helium in a container and supplied to the arc cavity. When etching AlN or Al2O3 in a fluorine-based plasma, for example, a stable / non-volatile AlF3 film can be formed on the surface of the aluminum-based ceramic, thereby passivating the surface. In this case, Ar + Ions can sputter surfaces and remove fluorides or leave surfaces fluoride-free, allowing for further reactions, such as:

[0032] AlN + F2 → AlF3 + N2 (1)

[0033] or

[0034] Al2O3+F2→AlF3+O2 (2).

[0035] This disclosure further considers that if the argon content in the argon + fluorine premixed bottle is reduced due to charge exchange resulting in a decrease in aluminum beam current, for example, the bottle may be filled with three or more gases, wherein the dominant or highest level gas is, for example, helium, with the remainder being a predetermined percentage of fluorine, argon, or other rare, inert, or other non-reactive gases.

[0036] To better understand this disclosure, according to one aspect of this disclosure... Figure 1 An exemplary vacuum system 100 is described. The vacuum system 100 in this embodiment includes an ion implantation system 101, but other types of vacuum systems, such as plasma processing systems or other semiconductor processing systems, are also contemplated. The ion implantation system 101 includes, for example, a terminal 102, a beam assembly 104, and a termination station 106.

[0037] Overall, the ion source 108 in terminal 102 is coupled to power supply 110 to ionize the dopant gas into multiple ions from the ion source to form ion beam 112. Individual electrodes adjacent to the extraction electrodes can be biased to suppress backflow of neutralized electrons near the source or returning to the extraction electrodes. The ion source material 113 of this disclosure is provided in ion source 108, wherein the ion source material includes aluminum-based source materials, such as solid alumina (Al₂O₃), aluminum nitride (AlN), or other aluminum-containing materials.

[0038] In this embodiment, the ion beam 112 is guided through the beam steering device 114 and exits through the aperture 116 toward the terminal station 106. At the terminal station 106, the ion beam 112 bombards a workpiece 118 (e.g., a semiconductor, such as a silicon wafer, display panel, etc.), which is selectively clamped or mounted onto a chuck 120 (e.g., an electrostatic chuck or ESC). Once embedded in the lattice of the workpiece 118, the implanted ions alter the physical and / or chemical properties of the workpiece. Therefore, ion implantation is used in semiconductor device fabrication and metal surface treatment, as well as in various applications in materials science research.

[0039] The ion beam 112 of this disclosure can be in any form, such as a pen or dot beam, a strip beam, a scanning beam, or any other form of ion-directed terminal station 106, all of which are considered to fall within the scope of this disclosure.

[0040] According to one exemplary aspect, terminal 106 includes a processing chamber 122, such as a vacuum chamber 124, wherein a processing environment 126 is associated with the processing chamber. The processing environment 126 is generally present within the processing chamber 122 and, in one embodiment, includes a vacuum generated by a vacuum source 128 (e.g., a vacuum pump), which is coupled to the processing chamber and configured to substantially evacuate the processing chamber. Furthermore, a controller 130 is provided for overall control of the vacuum system 100.

[0041] This disclosure understands that workpieces 118 on which silicon carbide-based devices are formed have been found to have better thermal and electrical properties than silicon-based devices, especially in applications involving high voltage and high temperature devices (e.g., electric vehicles). However, the types of implantation dopants used for ions implanted into silicon carbide differ from those used for silicon workpieces. In silicon carbide implantation, aluminum, nitrogen, and phosphorus implantation are frequently performed. Nitrogen and phosphorus implantation are relatively simple, for example, because nitrogen can be introduced as a gas and provides relatively easy conditioning, cleaning, etc. However, aluminum is more difficult because there is currently no known good aluminum aerosol.

[0042] This disclosure considers an ion source material 113, for example, an aluminum-based ion source material 132. Furthermore, an etchant gas mixture 134 is provided, whereby the introduction of the etchant gas mixture advantageously provides a high ion beam current and minimizes the harmful problems associated with higher pressures, which are associated with materials of larger molecular weight and further amplify the negative effects caused by the formation of insulating and / or conductive materials discussed above. In a particular embodiment, the invention considers an aluminum-based ion source material 132, such as comprising aluminum oxide (Al₂O₃) or aluminum nitride (AlN), to combine with the etchant gas mixture 134 to generate atomic aluminum ions, wherein the etchant gas mixture comprises a predetermined percentage of fluorine in an unreacted mixture of a rare or inert gas. Thus, at least in part due to the aforementioned increased pressure in the high-voltage gap between the ion source arc slit and the extraction electrode, the effects of insulating materials, debris, etc., are less harmful, thereby extending the lifespan of the ion source and electrodes, resulting in more stable ion beam operation, and substantially allowing for higher beam currents.

[0043] For example, aluminum-based ion source material 132 is incorporated into ceramic component 136 (e.g., repulsion axis, shield, or other component within ion source 108), wherein the ceramic is sputtered or etched using fluorine gas from etchant gas mixture 134. Aluminum-based ion source material 132, for example, is subjected to high-temperature treatment (e.g., 1000°C or higher), thereby enabling the ceramic to withstand such temperatures without melting.

[0044] Therefore, this disclosure generates monatomic ions, such as aluminum ions, to electrically dope silicon carbide, silicon, or other substrates at temperatures ranging from room temperature to about 1000°C or higher. Compared to prior art, this generation of monatomic ions advantageously results in improved source lifetime, higher beam current, and better operating characteristics.

[0045] According to an alternative aspect of this disclosure, aluminum-based ion source material can be supplied to ion source 108 via a solid-source vaporizer 140 of ion implantation system 101 (e.g., a suitable ion implanter manufactured by Axcelis Technologies, Beverley, MA). The solid-source vaporizer 140 associated with ion source 108, for example, can be loaded with aluminum-based ion source material and heated in the vaporizer until it forms vapor, which migrates to an ionization chamber where aluminum is ionized and extracted from the beam.

[0046] This disclosure further clarifies that providing fluorine gas at concentrations higher than predetermined health and safety levels (e.g., 10-20%) can present safety concerns related to the transport and storage of bottles containing fluorine gas. In manufacturing facilities, fluorine gas concentrations exceeding 20% ​​are generally not permitted due to its high hazard in the event of a leak.

[0047] Therefore, this disclosure provides an etchant gas mixture 134 comprising up to a predetermined health and safety level (e.g., approximately 20%) of fluorine, the balance of which comprises inert gases, rare gases, or other non-reactive gases, such as helium (He), argon (Ar), krypton (Kr), xenon (Xe), etc. This disclosure understands that helium will not harmfully affect the beam current; therefore, helium is premixed with fluorine for use in the etchant gas mixture 134. The etchant gas mixture 134 may be transported, for example, in a premixed bottle (e.g., 20% F, 80% He) to the location of the ion implantation system 101, whereby the helium and fluorine do not bind together or chemically bond, but are simply mixed, with helium acting as a diluent. In another embodiment, when sputtering aluminum-based ceramics is required, argon may also be included in the etchant gas mixture 134 as a co-gas 138 of helium and fluorine. For example, a small amount of argon may facilitate sputtering and break down any insulating coatings formed on the ceramic component 136. This co-occurring gas 138 can be provided, for example, together with other gases in the etchant gas mixture 134, or it can be provided separately from other sources. For example, the etchant gas mixture can be 0.5-5% argon, 20% fluorine, and the balance including helium.

[0048] Figure 2 An exemplary method 200 for implanting ions into a workpiece is described. It should be further noted that while the exemplary method herein is illustrated and described as a series of actions or events, it is to be understood that the invention is not limited to the order of such actions or events, as certain steps may occur in a different order and / or simultaneously with other steps not shown and described herein, according to the invention. Furthermore, not all illustrated steps are necessary for implementing the method according to the invention. Moreover, it is understood that these methods may be implemented in combination with the systems illustrated and described herein, as well as with other systems not described herein.

[0049] According to one exemplary aspect, in Figure 2In action 202, an aluminum source material is provided. The aluminum-based ion source material may, for example, be a solid ceramic component that is a component within the ion source. In action 204, for example, an etchant gas mixture is provided to the ion source. The etchant gas mixture may, for example, include a predetermined amount of fluorine mixed with a rare gas (e.g., helium). In action 206, the aluminum-based ion source material is ionized in the ion source, wherein fluorine etches the aluminum-based ion source material within the ion source to generate aluminum ions. In optional action 208, a companion gas (e.g., argon) is introduced into the ion source to sputter the ceramic component.

[0050] Although the present invention has been described and illustrated with respect to one or more embodiments, it should be noted that the above embodiments are merely examples of implementing certain embodiments of the invention, and the application of the invention is not limited to these embodiments. In particular, regarding the various functions performed by the aforementioned components (components, devices, circuits, etc.), unless otherwise specified, the terminology used to describe these components (including the reference to "component") refers to any component that corresponds to the specific function performed by the described component (i.e., functionally equivalent), even if it is structurally not equivalent to the disclosed structure performing the function in the exemplary embodiments of the invention described herein. Furthermore, although a particular feature of the invention is disclosed with respect to only one of several embodiments, this feature may be combined with one or more other features of other embodiments if it may be necessary or advantageous for any specific or particular application. Accordingly, the invention is not limited to the embodiments described above, but is intended to be limited to the appended claims and their equivalents.

Claims

1. An ion implantation system, comprising: Aluminum-based ion source materials; An ion source is configured to ionize the aluminum-based ion source material and form an ion beam, thereby the ionization of the aluminum-based ion source material further forms byproducts including non-conductive materials. An etchant gas mixture in fluid communication with the ion source, wherein the etchant gas mixture comprises fluorine gas and rare gases, wherein the rare gases comprise helium gas and argon gas at a content of less than 5%; A beam assembly configured to selectively deliver the ion beam; and The terminal station is configured to receive the ion beam to implant ions into the workpiece.

2. The ion implantation system according to claim 1, wherein, The predetermined fluorine content is associated with a predetermined health and safety level, wherein the predetermined health and safety level is a maximum fluorine content of 20%.

3. The ion implantation system according to claim 2, wherein, The etchant gas mixture includes a pressurized gas source.

4. The ion implantation system according to claim 1, wherein, The aluminum-based ion source material includes ceramic components, wherein the ceramic components include a repulsive pole axis and / or a shielding component.

5. The ion implantation system according to claim 1, wherein, The etchant gas mixture is in a premixed form in a pressurized bottle and includes a mixture of fluorine with argon and helium.

6. The ion implantation system according to claim 5, wherein, The pressurized bottle contains 20% or less fluorine.

7. An ion implantation system, comprising: Aluminum-based ion source materials; An ion source is configured to ionize the aluminum-based ion source material and form an ion beam, thereby the ionization of the aluminum-based ion source material further forms byproducts including non-conductive materials. An etchant gas supply comprising an etchant gas mixture of fluorine and a rare gas, wherein the etchant gas supply is configured to introduce the etchant gas mixture into the ion source, wherein the fluorine is mixed with the rare gas at a health-safe level, the rare gas comprising less than 5% argon, and the health-safe level is a maximum fluorine content of 20%. A beam assembly configured to selectively deliver the ion beam; and The terminal station is configured to receive the ion beam to implant ions into the workpiece.

8. The ion implantation system according to claim 7, wherein, The etchant gas supply includes a pressurized gas source.

9. The ion implantation system according to claim 8, wherein, The pressurized gas source includes a pressurized bottle containing the etchant gas mixture.

10. The ion implantation system according to claim 7, wherein, The etchant gas mixture is provided in the container in a premixed form.

11. The ion implantation system according to claim 10, wherein, The container is a pressurized bottle containing a mixture of fluorine, argon, and helium.

12. The ion implantation system according to claim 10, wherein, The container contains 20% fluorine.

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