Fluorine-based molecular co-gas when flowing dimethylaluminum chloride as a source material for generating an aluminum ion beam

Abstract

Ion implantation systems, ion sources, and methods are provided that have a gaseous aluminum-based ion source material. The gaseous aluminum-based ion source material may be or may include dimethylaluminum chloride (DMAC). DMAC is a liquid that transitions to a gas phase at room temperature. The ion source receives the gaseous aluminum-based ion source material and ionizes the material to form an ion beam. A low-pressure gas bottle supplies DMAC as a gas to the arc chamber of the ion source through a primary gas line. A separate secondary gas line supplies a co-gas, such as a fluorine-containing molecule, to the ion source. The co-gas and DMAC reduce energetic carbon cross-contamination and / or increase doubly charged aluminum.

Description

Detailed Description of the Invention

[0001] [Cross - Reference to Related Applications] This application claims the benefit of U.S. Provisional Application No. 63 / 107,729, filed October 30, 2020. The entire content of the provisional application is hereby incorporated by reference in its entirety into this specification.

[0002] [Field] The present invention generally relates to ion implantation systems. More specifically, the present invention relates to an ion implantation system that generates an ion beam containing aluminum ions from gaseous dimethylaluminum chloride (dimethylaluminum chloride: DMAC).

[0003] [Background] The demand for ion implantation using metal ions is increasing. For example, the implantation of aluminum is important for the power device market, which is growing rapidly in the market although on a small scale. For many metals including aluminum, it is a problem to supply the feedstock to the ion source. Systems have been conventionally provided that utilize a vaporizer, which is a small oven located outside the arc chamber of the ion source. The oven heats the metal salt to generate a sufficient vapor pressure to supply vapor to the ion source. However, the oven is separated from the arc chamber and takes time to heat to the desired temperature, establish a vapor flow, generate a plasma, and generate an ion beam. Further, when a change from one metal species to a plurality of other species is desired, it takes time to wait for the oven to be properly cooled (cooled down) for such a species change.

[0004] Another prior art aims to place a material containing a metal, such as aluminum or another metal (metal-containing material), inside the arc chamber. In the case of aluminum, the metal-containing material may include aluminum oxide, aluminum fluoride, or aluminum nitride. All of these can withstand the temperature of about 800 °C in the plasma chamber. In such a system, ions are directly ejected from the material in the plasma. Another technique aims to achieve chemical etching of metals using a plasma containing an etchant (etching agent) such as fluorine. Using these various techniques, an acceptable beam current can be obtained. However, compounds of aluminum oxide, aluminum chloride, and aluminum nitride, all of which are good electrical insulators, tend to deposit on the electrodes located near the ion source in a relatively short time (e.g., 5 to 10 hours). As a result, various harmful effects are observed, such as high voltage instability and related fluctuations in the dosage of the implanted ions.

[0005] [Summary] Accordingly, the present disclosure provides a system and apparatus for generating an ion beam containing aluminum ions from gaseous dimethylaluminum chloride (DMAC). Therefore, a simplified summary of the present disclosure is presented below to provide a basic understanding of several aspects of the present invention. This summary is not an extensive overview of the present invention. This summary is not intended to identify key elements of the present invention, nor is it intended to define the scope of the present invention. The purpose of this summary is to present some concepts of the present invention in a simplified form as a prelude to the detailed description that follows.

[0006] According to one aspect of the present disclosure, an ion implantation system is provided. A gaseous aluminum-based ion source material is provided. The ion source receives the gaseous aluminum-based ion source material and forms an ion beam from the material by ionizing the material. The beam line assembly selectively transports the ion beam. The end station receives the ion beam for implanting ions into a workpiece.

[0007] For example, the gaseous aluminum-based ion source material includes, or consists of, dimethylaluminum chloride (DMAC). For example, DMAC is stored as a liquid that transitions to the gas phase at room temperature at a predetermined negative pressure (e.g., vacuum pressure). For example, a pressurized gas bottle is configured to contain DMAC and supply the DMAC to the ion source. For example, the ion source includes an arc chamber. The pressurized gas bottle is configured to supply DMAC to the arc chamber. One or more dedicated supply lines (pipelines) may be further provided to transport DMAC from the pressurized gas bottle to the arc chamber. For example, a low-pressure gas container is configured to contain DMAC and supply the DMAC as a gas to the arc chamber of the ion source via a primary gas line.

[0008] For example, a co-gas source (auxiliary gas source) and a secondary gas line separate from the one or more dedicated supply lines are provided. The co-gas source and the secondary gas line are configured to supply co-gas to the ion source. For example, the co-gas includes one or more of BF3, SiF4, PF3, PF5, NF3, He+F2, and He+F2+Ar. The co-gas source may be pressurized or a sub-atmospheric gas source. In another example, the co-gas includes one or more of (i) a fluorine-containing compound and (ii) a mixture of fluorine and one or more inert gases (noble gases).

[0009] For example, a fluorine-containing molecule and DMAC are set to reduce energetic carbon cross-contamination (cross-contamination by carbon having energy). For example, the fluorine-containing compound may be further set to etch the ceramic in order to generate a larger beam current when flowing double-charged aluminum. For example, the co-gas includes a fluorine-containing molecule mixed with an inert gas.

[0010] A vacuum system may be further provided. The vacuum system may be configured to substantially evacuate one or more surrounding portions of the ion implantation system. For example, one or more surrounding portions of the ion implantation system may include an ion source.

[0011] According to another exemplary aspect, an ion source for an ion implantation system is provided. For example, the ion source includes an arc chamber, a DMAC source material, and one or more source material supply lines configured to transport the DMAC source material to the arc chamber. For example, the arc chamber is configured to ionize the DMAC source material. For example, a pressurized gas bottle may be configured to contain the DMAC source material.

[0012] For example, one or more co-gas supply source lines may be further configured to supply the co-gas to the arc chamber. For example, the co-gas may include one or more of (i) a fluorine-containing compound and (ii) a mixture of fluorine and one or more inert gases. For example, the co-gas includes one or more of BF3, SiF4, PF3, PF5, NF3, He+F2, and He+F2+Ar. The vacuum system may be further configured to substantially evacuate one or more surrounding portions of the ion source.

[0013] According to another exemplary aspect of the present invention, a method for implanting aluminum ions into a workpiece is provided. The method includes, for example, the step of supplying an aluminum-based source material containing DMAC to an ion source. The aluminum-based source material is ionized inside the ion source. Aluminum ions are extracted from the ion source. Further, aluminum ions derived from the ionized aluminum-based source material are implanted into the workpiece.

[0014] For example, DMAC is supplied from a pressurized gas source to the arc chamber of the ion source. In another example, a co-gas is further provided to the ion source. For example, the co-gas may include one or more of (i) a fluorine-containing compound and (ii) a mixture of fluorine and one or more inert gases. For example, the co-gas may include one or more of BF3, SiF4, PF3, PF5, NF3, He+F2, and He+F2+Ar.

[0015] According to still another exemplary aspect of the present invention, an ion implantation system including a gaseous aluminum-based ion source material is provided. For example, the gaseous aluminum-based ion source material contains or consists of DMAC. DMAC is a liquid that transfers to the gas phase at room temperature. For example, the ion implantation system further includes an ion source. The ion source is configured to receive the aluminum-based ion source material, ionize the material, and form an ion beam from the material. For example, the beam line assembly is configured to selectively transport the ion beam. The end station is configured to receive the ion beam for implanting ions into the workpiece.

[0016] For example, the gaseous aluminum-based ion source material is in a liquid state in a low-pressure bottle and transfers to the gas phase upon introduction to the ion source.

[0017] According to a further exemplary aspect of the present invention, an ion source is provided. The ion source includes an arc chamber and a DMAC source containing a DMAC source material. For example, one or more supply lines are configured to transport the DMAC source material from the DMAC source to the arc chamber. For example, the DMAC source material is a liquid that transitions to the gas phase at room temperature.

[0018] For example, one or more supply lines include dedicated gas lines configured to exclusively transport the DMAC source material from the DMAC source to the arc chamber. In another example, an inert gas source containing an inert gas is provided. One or more supply lines are further configured to transport the inert gas to the arc chamber. For example, one or more supply lines may include a single supply line configured to supply a mixture of the DMAC source material and the inert gas to the arc chamber. In another example, the DMAC source material and the inert gas are pre-mixed within a common source.

[0019] For example, a co-gas source and one or more co-gas supply lines may be configured to supply a co-gas from the co-gas source to the arc chamber. For example, one or more co-gas supply lines are different from one or more supply lines. For example, the co-gas includes fluorine-containing molecules set to reduce energy carbon cross-contamination inside the arc chamber. For example, the fluorine-containing molecules include one or more of BF3, PF3, PF5, NF3, and SiF4. In another example, a ceramic target is provided and disposed within the arc chamber. For example, the ceramic target contains aluminum. The ceramic target is etched by the fluorine-containing molecules.

[0020] In another example, the co-gas is a pre-mixture of a plurality of gases. At least one component of the pre-mixture of the gases is fluorine. Fluorine is set to reduce energy cross-contamination in the arc chamber. For example, the pre-mixture of the gases includes one or more of argon and helium in addition to fluorine. For example, the pre-mixture of the gases includes one or more of (Ar+F2), (He+F2), and (Ar+He+F2).

[0021] Therefore, according to one exemplary aspect, an ion implantation system for implanting aluminum ions is provided. The electrode power supply is electrically connected to an electrode (e.g., cathode) in the arc chamber. A process gas source containing (e.g., in a liquid state) DMAC is fluidly connected to the arc chamber via a process gas supply line. The process gas supply line is configured to selectively transport DMAC in gaseous form from the process gas source to the arc chamber. For example, the electrode is configured to form (generate) a plasma from DMAC inside the arc chamber based at least in part on the energy (e.g., current) supplied to the electrode from the electrode power supply. Thus, in order to generate at least C2H3, DMAC is ionized, or decomposed or dissociated. C2H3 has a mass close to that of atomic aluminum.

[0022] For example, a co-gas source containing a co-gas containing fluorine is further provided. For example, fluorine may be molecular or in a gaseous form mixed with an inert gas. For example, the co-gas supply line fluidly connects the co-gas source and the arc chamber. The co-gas supply line is configured to selectively transport the co-gas from the co-gas source to the arc chamber. For example, the co-gas supply line is different from and spaced apart from the process gas supply line. For example, fluorine from the co-gas source is configured to react with at least C2H3 to generate CF x is generated. CFx By generating [it], the remaining (available) C2H3 in the arc chamber is minimized. Thereby, beneficially, CF having an atomic mass different from that of atomic aluminum x can be separated from aluminum ions by subsequent mass spectrometry.

[0023] In another example, an extraction electrode is provided. The extraction electrode is configured to extract an aluminum-based ion beam from the arc chamber based on the bias of the extraction electrode with respect to the arc chamber. For example, by arranging the extraction electrode near the extraction opening of the arc chamber, an aluminum-based ion beam is formed. For example, a mass spectrometer is further arranged downstream of the extraction electrode. The mass spectrometer is configured to perform mass spectrometry on the aluminum-based ion beam to remove (eliminate) CF x Thereby, an aluminum ion beam (mass-analyzed aluminum ion beam) can be defined after mass spectrometry. And, beneficially, the energy cross-contamination caused by C2H3 in the aluminum ion beam after mass spectrometry is minimized.

[0024] In another example, a ceramic target is further arranged in the arc chamber or the ceramic target is provided in the arc chamber by another method. The ceramic target contains aluminum. Fluorine is configured to etch the ceramic target to increase the beam current of the aluminum-based ion beam. For example, the aluminum-based ion beam may contain doubly charged aluminum ions.

[0025] To achieve the above and related objectives, the present disclosure includes the configurations that are fully described below and particularly recited in the claims. The following description and the accompanying drawings show exemplary embodiments of the present invention in detail. However, these embodiments merely show a part of various ways of using the principles of the present invention. Other objectives, advantages, and novel configurations of the present invention will become apparent from the detailed description of the present invention with reference to the drawings.

Brief Description of the Drawings

[0026]

Figure 1

Figure 2

Figure 3

Figure 4

[0027] [Detailed Description] The present disclosure generally relates to ion implantation systems and ion source materials related to such ion implantation systems. More specifically, the present disclosure relates to components for such ion implantation systems that use dimethylaluminum chloride as an ion source material for generating atomic ions for electrically doping silicon (silicon), silicon carbide (silicon carbide), or other semiconductor substrates at various temperatures. Advantageously, the present disclosure minimizes carbon energy cross-contamination during aluminum implantation when using dimethylaluminum chloride as the ion source material. Further, the present disclosure minimizes various deposits on the extraction electrode and source chamber components. Accordingly, the present disclosure reduces related arc discharge (arcing) and glitching and further increases the overall life of the ion source and related electrodes.

[0028] Accordingly, the present invention will be described below with reference to the drawings, and like reference numerals may be used throughout to refer to like elements (members). It should be understood that the description of these aspects is merely illustrative and should not be construed in a limiting sense. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. However, it will be apparent to one of ordinary skill in the art that the present invention may be practiced without these specific details. Also, the scope of the present invention is not intended to be limited by the embodiments or examples described below, but is intended to be limited only by the claims and their equivalents.

[0029] The drawings are provided to illustrate examples of multiple aspects of embodiments of the present disclosure, and thus it should also be noted that they are to be regarded as merely schematic. In particular, the elements shown in the drawings are not necessarily to scale with each other. Also, the arrangement of various elements in the drawings is selected to provide a clear understanding of each embodiment, and should not necessarily be construed as representing the actual relative positions of various components in the implementation according to the embodiments of the present invention. Furthermore, the configurations in various embodiments and examples described in this specification may be combined with each other unless otherwise specified.

[0030] In the following description, it should also be understood that any direct connection or coupling between functional blocks, devices, components, or other physical or functional units shown in the drawings or described in this specification may be implemented by an indirect connection or coupling. Furthermore, it should be understood that the functional blocks or units shown in the drawings may be implemented as individual configurations in one embodiment, or alternatively, in another embodiment, may be implemented as a completely or partially common configuration.

[0031] Ion implantation is a physical process used in semiconductor device manufacturing to selectively implant dopants into semiconductor materials and / or wafer materials. Therefore, the behavior of implantation does not depend on the chemical interaction between the dopant and the semiconductor material. For ion implantation, dopant atoms / molecules from the ion source of an ion implantation apparatus are ionized, accelerated, formed into an ion beam, analyzed, and scanned across the wafer or the wafer is moved to pass through the ion beam. The dopant ions physically collide with the wafer and enter the surface, and come to rest at a depth related to their energy below the surface.

[0032] Typically, an ion source within an ion implantation apparatus generates an ion beam by ionizing a source material within an arc chamber. The component of the source material is the desired dopant element. The desired dopant element is then extracted from the ionized source material in the form of an ion beam.

[0033] To obtain a general understanding of the present disclosure, according to one aspect of the present disclosure, FIG. 1 shows an exemplary vacuum system 100. The vacuum system 100 in this example includes an ion implantation system 101. However, various other types of vacuum systems are also contemplated, such as plasma processing systems or other semiconductor processing systems. As an example, the ion implantation system 101 includes a terminal 102, a beam line assembly 104, and an end station 106.

[0034] Generally, the ion source 108 within the terminal 102 is connected to a power supply 110 and ionizes dopant gas from the ion source into a plurality of ions to form an ion beam 112. The ion beam 112 in this example is directed through a mass spectrometer 114 (e.g., a beam steering device), exits through an aperture 116, and is directed towards the end station 106. For example, the mass spectrometer 114 includes a magnetic field generating component such as a magnet. The mass spectrometer 114 operates to supply a magnetic field that intersects the path 117 of the ion beam 112 and deflects the ions from the ion beam along trajectories that vary according to mass (e.g., mass-to-charge ratio). Ions moving through the magnetic field are subject to a force that deflects them to guide individual ions of a desired mass along the path 117 and away from ions of undesired mass from that path. Inside the end station 106, the ion beam 112 impinges on a workpiece 118 (e.g., a semiconductor such as a silicon wafer, a display panel, etc.). The workpiece is selectively clamped or attached to a chuck 120 (e.g., an electrostatic chuck or ESC). When the implanted ions are embedded within the lattice of the workpiece 118, they change the physical and / or chemical properties of the workpiece. Thus, ion implantation is used in various applications in materials science research in addition to semiconductor device manufacturing and metal finishing.

[0035] The ion beam 112 of the present disclosure can take any form, such as a pencil beam, a spot beam, a ribbon beam, a scanning beam (scan beam), or any other form in which ions are directed towards the end station 106. All such forms are considered to be within the scope of the present disclosure.

[0036] According to an exemplary aspect, the end station 106 includes a process chamber 122, such as a vacuum chamber 124. A process environment 126 is associated with the process chamber. The process environment 126 generally exists within the process chamber 122. Also, for example, the process chamber includes a vacuum generated by a vacuum source 128 (e.g., a vacuum pump). The vacuum source is connected to the process chamber and is configured to substantially evacuate the process chamber. Further, a controller 130 is provided for overall control of the vacuum system 100.

[0037] It is understood that the present disclosure has found that a workpiece 118 having a silicon carbide-based device formed on its surface has better thermal and electrical properties than silicon-based devices, particularly in applications used for high-voltage and high-temperature devices such as electric vehicles. However, ion implantation into silicon carbide utilizes a different class of implant dopants than those used for silicon workpieces. In silicon carbide implantation, implantation of aluminum, phosphorus, and nitrogen is often performed. For example, nitrogen implantation is relatively simple because nitrogen can be introduced as a gas and provides relatively easy tuning and cleaning. However, aluminum is more difficult because there is little known good gaseous solution of aluminum.

[0038] For example, the present invention contemplates that ion source material 132 is supplied to arc chamber 134 of ion source 108 to form ion beam 112. Ion beam 112 is extracted through extraction opening 140 of arc chamber 134 via the electrical bias of associated extraction electrode 142. To generate ion beam 112 for subsequent aluminum ion implantation, a material that can be safely and efficiently supplied to ion source 108 in gaseous form has not heretofore existed. Heretofore, some solid source material (not shown) has been placed within a heated vaporizer assembly (not shown). In this case, the resulting gas is supplied into arc chamber 134. Alternatively, a solid and high-temperature ceramic such as Al2O3 or AlN (not shown) is placed within the arc chamber. Within the arc chamber, the ceramic is etched by a fluorine-based gas.

[0039] However, both of these techniques can have substantial limitations. For example, the time to reach the temperature required for the vaporizer to transfer solid material to the gas phase can be longer than 30 minutes. This can affect the productivity of the tool. Further, if it is desired to introduce different dopant gases into the arc chamber, the time required to subsequently lower the temperature of the vaporizer so that the source material is no longer in the gas phase can be longer than 30 minutes. This time is generally referred to as the interspecies transfer time. The transfer time can reduce the productivity of the ion implantation apparatus.

[0040] Furthermore, when etching a ceramic of aluminum oxide (Al2O3) or aluminum nitride (AlN) using a fluorine-based dopant gas (e.g., BF3, NF3, PF3, PF5), by-products obtained as a result of the reaction (e.g., AlF x, Al, N, and neutral substances of AlN and Al2O3) can form an insulating coating on the extraction electrode (e.g., at a negative voltage). This, in turn, can cause charge accumulation and subsequent discharge to the ion source arc slit optical plate (e.g., at a positive voltage). Therefore, the productivity of the tool is further reduced.

[0041] Ion implantation system 101 of the present invention supplies gaseous dimethylaluminum chloride (C4H 10 AlCl, also referred to as DMAC) as the ion source material 132, and advantageously supplies the aluminum-based material in gaseous form to the arc chamber 134 of the ion source 108. For example, supplying DMAC in gaseous form to the arc chamber 134 is beneficial in that there is no waiting time for heating (warming up) and cooling (cooling down) of the material, and there is no formation of insulating material on the extraction electrode as observed in conventional systems, realizing a faster transition time between species (e.g., less than 5 minutes).

[0042] DMAC is stored in a pressurized gas bottle as a liquid that transitions to the gas phase at room temperature at a predetermined pressure (e.g., vacuum). For example, since the ion source material 132 (e.g., DMAC) is a highly reactive material (pyrophoric), it is selectively supplied to the arc chamber 134 via a dedicated primary gas line 136. A fluorine-containing gas source 144 (e.g., BF3, PF3, etc.) is selectively supplied to the arc chamber 134 via a secondary gas line 146. The primary gas line 136 and the secondary gas line are separate and distinct gas lines. The fluorine-containing gas source 144 is, for example, a molecule or a premix of a gas in which at least one component is fluorine.

[0043] The inventors have observed that for singly-charged aluminum (Al+), a large beam current (e.g., greater than about 30 mA) can be achieved, but for doubly-charged (Al++) the beam current is quite small (e.g., less than about 5 mA). To promote the generation of doubly-charged aluminum, a ceramic target made of either AlN or Al2O3, for example, may be placed on or near the shaft. The shaft is made of a heat-resistant metal and can be biased to a negative potential. For example, by biasing the shaft to a negative potential, a negative electric field is generated that accelerates ions towards the surface (e.g., the ion current increases). This then causes the temperature of the heat-resistant metal shaft and the aluminum-based ceramic target to increase. When using fluorine-based gas molecules, this temperature increase increases the etching rate of the aluminum-based ceramic and generates AlF x . Then, AlF x is decomposed in the plasma to produce Al+ and F. For example, the following reactions, AlN + F2 → AlF3 + N2 (1) and, Al2O3 + F2 → AlF3 + O2 (2) can occur.

[0044] Accompanying sputtering of the ceramic target also occurs, producing neutral particles of nitrogen, oxygen, and aluminum. The neutral particles can be further ionized inside the plasma. Providing an aluminum-based sputtering / etching target in combination with one or more of DMAC, and (i) fluorine-containing molecules (e.g., BF3, PF3, PF5, etc.), and (ii) a premixed gas where at least one component is fluorine (e.g., BF3 + Ar, He + F2, etc.) achieves a lower flow rate of DMAC to the ion source. As a result, the internal pressure of the arc chamber can be reduced (e.g., due to a decrease in charge exchange, a longer mean free path). This can be further beneficial for the generation of doubly-charged aluminum ions.

[0045] For example, the reaction between fluorine and hydrogen is beneficial for the generation of doubly charged aluminum. This is because a high hydrogen level correlates with a lower current of doubly charged aluminum due to the following reaction, H+F→HF (3) Furthermore, the chlorine component of DMAC etches AlN and / or Al2O3 to generate AlCl as follows:

[0046] Al+Cl2→AlCl3(4) Al+Cl2→AlCl3(4) AlCl x is generated. Subsequently, AlCl x can be ionized in the plasma.

[0047] According to another example, a further advantage of using a fluorine-based molecule as a co-gas when flowing DMAC is the reduction of energy carbon cross-contamination. The co-gas can include one or more of (i) a fluorine-containing molecule and (ii) a mixture of fluorine and one or more inert gases. For example, the co-gas includes one or more of BF3, SiF4, PF3, PF5, NF3, He+F2 (which may also be referred to as HeF2), and He+F2+Ar (which may also be referred to as HeF2Ar). For example, by adding a fluorine-based compound (e.g., BF3) or a preliminary mixture of other gases in which at least one component is fluorine (e.g., He+F2) to the supply of DMAC, when comparing the AMU spectrum 202 of the 85V bias electrode with the AMU spectrum 204 of the 85V bias electrode with the supply of BF3 as shown in the graph 200 of FIG. 2, it is observed that the contamination level has decreased by approximately 50% from 2.05e17 to 1e17.

[0048] Based at least in part on the comparison of the AMU spectra 202, 204, 206, and 208 in FIG. 2 and the AMU spectrum value comparison 300 shown in FIG. 3, the present disclosure understands the potential mechanisms of such variations. For example, fluorine (F) can scavenge hydrogen (H) atoms from carbon (C), so C2Hx Reduce the generation of species (e.g., C2H3 has approximately the same atomic weight as Al+). In another example, fluorine (F) can break carbon-carbon bonds (C-C). That is, the following reaction, C2H3 + 5F → 2CF + 3HF (5) occurs, and CF x can occur.

[0049] Figure 4 shows an exemplary method 400 for implanting aluminum ions into a workpiece. The exemplary method is illustrated and described herein as a series of acts or events. However, it should be further understood that the present invention is not limited by the illustrated order of such acts or events. This is because some steps can occur in a different order and / or can occur simultaneously with steps other than those illustrated and described herein. In addition, not all of the illustrated steps are required to practice the method according to the present invention. Further, the method can be practiced not only in connection with the systems illustrated and described herein, but also in connection with other systems not described.

[0050] According to an exemplary aspect, in act 402 of FIG. 4, a gaseous ion source material is supplied in the form of dimethylaluminum chloride (DMAC). The gaseous ion source material can be supplied, for example, within a low-pressure bottle (e.g., about 10 - 15 torr). In act 404, the DMAC flows as a gas from the low-pressure bottle into the arc chamber of the ion source. In act 406, the ion source material containing DMAC is ionized inside the ion source, generating aluminum ions. In act 408, the aluminum ions are extracted from the ion source to form an ion beam containing aluminum ions. In act 410, the aluminum ions are implanted into the workpiece.

[0051] Although one or more of the above-described embodiments have been described, the above-described embodiments are merely examples for implementing some embodiments of the present invention, and the scope of application of the present invention is not limited to these embodiments. In particular, with respect to the various functions realized by the above components (assemblies, devices, circuits, etc.), the terms used to describe the components (including references to "means") are not structurally equivalent to the disclosed structures that realize the functions in the exemplary embodiments of the present invention illustrated herein, unless otherwise specified, but are intended to correspond to any component (i.e., functionally equivalent) that realizes the specified function of the described component. Further, although a particular configuration of the present invention has been disclosed for only one of the plurality of embodiments, the configuration can be combined with one or more configurations in other embodiments that are desirable and advantageous for a given or particular application. Therefore, the present invention is not intended to be limited to the above-described embodiments, but is intended to be limited only by the appended claims and their equivalents.

Claims

1. An ion implantation system for implanting aluminum ions, including an electrode power supply, an arc chamber having an electrode electrically connected to the electrode power supply, a process gas source containing dimethylaluminum chloride (DMAC), a process gas supply line fluidly connected between the process gas source and the arc chamber, a co-gas source containing a co-gas containing fluorine, and a co-gas supply line fluidly connected between the co-gas source and the arc chamber, wherein the process gas supply line selectively transports the DMAC from the process gas source to the arc chamber, the electrode decomposes the DMAC by generating plasma from the DMAC in the arc chamber based at least in part on energy supplied from the electrode power supply to the electrode, and C having a mass close to that of atomic aluminum ２ H ３ is at least generated, the co-gas supply line selectively transports the co-gas from the co-gas source to the arc chamber, the co-gas supply line is different from the process gas supply line, the fluorine reacts with at least the C ２ H ３ to generate CF ｘ and the amount of C remaining in the arc chamber ２ H ３ is minimized. An ion implantation system.

2. The ion implantation system according to claim 1, wherein the process gas source maintains the DMAC in a liquid state.

3. The ion implantation system according to claim 2, wherein the process gas source includes a pressurized gas bottle containing the DMAC.

4. The co-gas-containing ion implantation system according to claim 1, wherein the co-gas contains a fluorine-containing molecule.

5. The fluorine-containing molecule is BF ３ , SiF ４ , PF ３ , PF ５ , or NF ３ The ion implantation system according to claim 4, which contains.

6. The co-gas-containing ion implantation system according to claim 1, wherein the co-gas contains an inert gas mixed with fluorine gas (F ２ ) at a predetermined concentration.

7. The ion implantation system according to claim 6, wherein the inert gas contains one or more of helium and argon.

8. The co-gas source-containing ion implantation system according to claim 1, which contains one or more pressurized gas sources.

9. The ion implantation system is An extraction electrode, A mass spectrometer disposed downstream of the extraction electrode, and further includes, Based on the bias of the extraction electrode with respect to the arc chamber, the extraction electrode extracts an aluminum-based ion beam from the arc chamber, The mass spectrometer mass-analyzes the aluminum-based ion beam to remove the CF ｘ , thereby defining an aluminum ion beam after mass analysis, and minimizing energy cross-contamination caused by C ２ H ３ in the aluminum ion beam after mass analysis. The ion implantation system according to claim 1.

10. The ion implantation system further includes a ceramic target disposed in the arc chamber. The above-mentioned ceramic target contains aluminum, and the above-mentioned fluorine etches the above-mentioned ceramic target. The ion implantation system according to claim 9.

11. The above-mentioned aluminum-based ion beam contains doubly charged aluminum ions. The ion implantation system according to claim 10.

12. A system for implanting aluminum ions into a workpiece, An ion source, An extraction electrode, A mass spectrometer, and is provided with, The above-mentioned ion source, Has one or more electrodes operably connected to an electrode power supply, and further has an arc chamber with an extraction opening, A process gas source containing dimethylaluminum chloride (DMAC), A process gas supply line fluidly connecting the above-mentioned process gas source to the above-mentioned arc chamber, A co-gas source containing a co-gas containing fluorine, A co-gas supply line fluidly connecting the above-mentioned co-gas source to the above-mentioned arc chamber, and is provided with, The above-mentioned process gas supply line selectively transports the above-mentioned DMAC from the above-mentioned process gas source to the above-mentioned arc chamber, Based at least in part on the energy supplied from the above-mentioned electrode power supply to the above-mentioned one or more electrodes, the above-mentioned DMAC is decomposed by generating plasma from the above-mentioned DMAC in the above-mentioned arc chamber, and has a mass close to that of atomic aluminum C ２ H ３ Is at least generated, The above-mentioned co-gas supply line selectively transports the above-mentioned co-gas from the above-mentioned co-gas source to the above-mentioned arc chamber, The above-mentioned co-gas supply line is different from the above-mentioned process gas supply line, The above-mentioned fluorine reacts with at least the above-mentioned C ２ H ３ To produce CF ｘoccurs, and the amount of C remaining in the arc chamber is minimized, ２ H ３ and the extraction electrode is located near the extraction opening of the arc chamber, and the extraction electrode extracts an aluminum-based ion beam from the arc chamber based on the bias of the extraction electrode with respect to the arc chamber, and the mass analyzer is disposed downstream of the extraction electrode, and the mass analyzer mass-analyzes the aluminum-based ion beam to remove the CF thereby defining an aluminum ion beam after mass analysis, and minimizing energy cross-contamination caused by C ｘ in the aluminum ion beam after mass analysis. ２ H ３ A system.

13. The system according to claim 12, wherein the process gas source includes a pressurized gas bottle containing the DMAc.

14. The co-gas is BF ３ , SiF ４ , PF ３ , PF ５ , or NF ３ The system according to claim 12, including one or more of them.

15. The co-gas includes an inert gas mixed with a fluorine gas (F ２ ) at a predetermined concentration. The system according to claim 12.

16. The system further includes a ceramic target disposed in the arc chamber, the ceramic target contains aluminum, and the fluorine etches the ceramic target and increases the beam current of the aluminum-based ion beam. The system according to claim 12.

17. The aluminum-based ion beam system according to claim 16, which contains doubly charged aluminum ions.

18. A system for implanting aluminum ions into a workpiece, comprising: an ion source; an extraction electrode; a mass spectrometer, wherein the ion source comprises: an arc chamber having an extraction opening; one or more electrodes electrically connected to an electrode power supply; a ceramic target disposed in the arc chamber and containing aluminum; a process gas source containing dimethylaluminum chloride (DMAC) in a liquid form; a process gas supply line fluidly connecting the process gas source to the arc chamber; a co-gas source containing a co-gas containing fluorine; a co-gas supply line fluidly connecting the co-gas source to the arc chamber, wherein the process gas supply line selectively transports the DMAC from the process gas source to the arc chamber in a gaseous form, at least one of the electrodes generates plasma from the DMAC in the arc chamber at least partially based on the energy supplied from the electrode power supply to the electrode, whereby the DMAC is decomposed and C having a mass close to atomic aluminum ２ H ３ is at least generated, wherein the co-gas supply line selectively transports the co-gas from the co-gas source to the arc chamber, the co-gas supply line is different from the process gas supply line, wherein the fluorine reacts with at least the C ２ H ３ to produce CF ｘ and the remaining C in the arc chamber ２ H ３ The amount of The fluorine etches the ceramic target, The extraction electrode is located near the extraction opening of the arc chamber, Based on the bias of the extraction electrode with respect to the arc chamber, the extraction electrode extracts an aluminum-based ion beam from the arc chamber, The mass spectrometer is arranged downstream of the extraction opening, The mass spectrometer mass-analyzes the aluminum-based ion beam to remove the CF ｘ By removing it, an aluminum ion beam after mass analysis is defined, and the energy cross-contamination caused by C ２ H ３ in the aluminum ion beam after mass analysis is minimized. A system.

19. The fluorine etches the ceramic target and increases the beam current of the aluminum-based ion beam. The system according to claim 16.

20. The ceramic target contains Al ２ O ３ or AlN. The system according to claim 16.

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