KR20160089490A - Method for implant productivity enhancement - Google Patents

Abstract

A method of processing a workpiece is disclosed, wherein the ion chamber is first coated with the desired dopant species and other species. Following this conditioning process, a feed gas comprising fluorine and the desired dopant is introduced into the chamber and ionized. The ions are then extracted from the chamber and accelerated toward the workpiece, where the ions are first injected without being mass analyzed. Other species used during the conditioning process may be Group 3, Group 4, or Group 5 elements. The dopant species desired may be boron.

Description

[0001] METHOD FOR IMPLANT PRODUCTIVITY ENHANCEMENT [0002]

This application claims priority to U.S. Provisional Patent Application Serial No. 61 / 847,776, filed July 18, 2013, the disclosure of which is incorporated by reference.

Technical field

Embodiments of the present disclosure are directed to methods for improving ion beam quality in an ion implantation system, and more particularly, to methods for improving boron ion beam quality.

Semiconductor workpieces are usually implanted into the dopant species to produce the desired conductivity. For example, the solar cells may be implanted into the dopant species to create an emissive region. This implantation can be accomplished using a variety of different mechanisms. In one embodiment, an ion source is used. Such an ion source may include a chamber within which the source gases are ionized. Ions from these source gases can be extracted through the openings in the chamber using one or more electrodes. These extracted ions are directed toward the workpiece, where the ions are injected into the workpiece to form a solar cell.

In an effort to improve process efficiency and lower costs, in some embodiments, the ions extracted from the ion source are accelerated directly toward the workpiece without any mass analysis. In other words, the ions generated in the ion source are accelerated and injected directly into the workpiece. A mass spectrometer is used to remove unwanted species from the ion beam. Removal of the mass spectrometer means that all ions extracted from the ion source will be injected into the workpiece. As a result, undesired ions, which can also be generated in the ion source, are then injected into the workpiece.

This phenomenon may be most noticeable when the source gas is a halogen-based compound such as a fluoride. (Metastable or excited) neutral particles and fluorine ions may react with the inner surfaces of the ion source, which may include silicon, oxygen, carbon, and aluminum and heavy metals present as unwanted ions, such as impurity elements Release.

Thus, a method of improving beam quality, particularly a method of improving beam quality for embodiments in which halogen-based source gases are used, would be beneficial.

A method of processing a workpiece is disclosed, wherein the ion chamber is first coated with the desired dopant species and other species. Following this conditioning process, a feed gas containing fluorine and the desired dopant species is introduced into the chamber and ionized. The ions are then extracted from the chamber and accelerated toward the workpiece, where the ions are first injected without being mass analyzed. Other species used during the conditioning process may be Group 3, Group 4, or Group 5 elements. The dopant species desired may be boron.

In one embodiment, a method for processing a workpiece is disclosed. The method includes the steps of introducing a conditioning gas into a chamber of an ion source, wherein the conditioning gas comprises a hydride and a conditioning co-gas comprising a desired dopant species, the conditioning nose gas comprises an inert gas, A hydride of a Group 4 element, or a hydride of a species having a conductivity opposite to the desired dopant species, wherein between about 10% and 40% of the total volume of introduced gas comprises a conditioning nose gas; Ionizing the conditioning gas and the conditioning nose gas to form a coating on the walls of the chamber; Modifying the gases introduced into the chamber after formation of the coating and introducing the feed gas into the chamber, wherein the feed gas comprises fluorine and the desired dopant species; Ionizing the feed gas in the chamber to produce ions; And extracting ions from the chamber and accelerating the ions toward the workpiece so that the ions can be injected into the workpiece without mass analysis.

In a second embodiment, a method of processing a workpiece is disclosed, the method comprising: introducing a conditioning gas into a chamber of an ion source, wherein the conditioning gas comprises a borane and a conditioning nose- Wherein the conditioning co-gas comprises a hydride of a Group 4 or Group 5 element; Forming a coating on the walls of the chamber, wherein the coating comprises boron and Group 4 or Group 5 elements; Introducing a feed gas into the chamber after formation of the coating, wherein the feed gas comprises fluorine and boron; Ionizing the feed gas in the chamber to produce ions; And extracting ions from the chamber and accelerating ions toward the workpiece.

In a third embodiment, a method of processing works is disclosed. The method includes performing a conditioning process on the chamber of the ion source to coat the walls of the chamber with boron and Group 4 or Group 5 elements; And performing a post-implantation process after the coating is formed on the walls, wherein a feed gas comprising fluorine and boron is ionized to produce ions, ions are extracted from the chamber and accelerated toward the workpiece, Into the workpieces without the need for a vacuum. In some embodiments, the conditioning process includes ionizing a conditioning nose gas comprising a conditioning gas comprising borane and a hydride of a Group 4 or Group 5 element in the chamber. In some additional embodiments, the conditioning co-gas may be phosphine (PH ₃ ), arsine (AsH ₃ ), germane (GeH ₄ ), or silane (SiH ₄ ).

For a better understanding of the disclosure, reference is made to the accompanying drawings, which are incorporated herein by reference.
Figures 1A-1C illustrate an injection system according to different embodiments.
Figure 2 is a representative graph of dopant current and contaminant level as a function of diluent gas concentration.
Figures 3A-B illustrate contaminants as a percentage of total beam current using two different conditioning procedures.
Figures 4A-4B show the differences between the two conditioning procedures.

As described above, ionization of halogen-based species such as fluorides can result in particles being released from the inner surfaces of the ion source being injected into the workpiece. These contaminants may include aluminum, carbon, nitrogen, oxygen, silicon, fluorine-based compounds, and other unwanted species (including heavy metals present as impurity elements). One approach to address the damage caused by free halogen ions may be to introduce a second source gas during implantation.

1A-1C illustrate various embodiments in which a second source gas may be introduced into the chamber 105 of the ion source 100. In each of these figures, the ion source 100 includes a chamber 105 that is defined by several chamber walls 107, which may be made of graphite or other suitable material. In this chamber 105, one or more source gases stored in the source gas container 170 may be supplied through the gas inlet 110. This source gas may be energized by the RF antenna 120 or other mechanism. The RF antenna 120 is in electrical communication with an RF power supply (not shown) that supplies power to the RF antenna 120. A dielectric window 125, such as a quartz or alumina window, may be disposed between the RF antenna 120 and the interior of the ion source 100. The ion source 100 also includes an opening 140 through which ions can pass. A negative voltage is applied to the extraction inhibitor electrode 140 disposed outside the opening 140 to extract positively charged ions from within the chamber 105 through the opening 140 and toward the workpiece 160. [ (130). A ground electrode 150 may also be used. In some embodiments, the opening 140 is positioned on the side of the ion source 100 opposite the side comprising the dielectric window 125. Ions extracted from the chamber 105 are formed into an ion beam 180 and the ion beam is directed toward the workpiece 160. As described above, no mass analyzer is used to filter the ions before the ions collide with the workpiece 160. 1A, a secondary source gas is stored in a second gas container 175 and is introduced into the chamber 105 through a second gas inlet 111. In one particular embodiment, 1B, a secondary source gas is stored in the second gas container 176 and introduced into the chamber 105 through the same gas inlet 110 as used by the first source gas. do. 1C, the second source gas may be mixed with the first source gas in a single gas container 178. In one embodiment, This mixture of gases is then introduced into the chamber 105 through the gas inlet 110.

In any of these embodiments, the first source gas and the second source gas may be introduced into the chamber 105 simultaneously or sequentially.

The first source gas, also referred to as the feed gas, may comprise a dopant such as boron combined with fluorine. Thus, the feed gas may be in the form of DF _n or D _m F _n , where D represents a dopant atom, which may be boron, gallium, phosphorus, arsenic, or other Group 3 or Group 5 elements. The second source gas, which may also be referred to as a diluent gas, can be a molecule having the formula XH _n or X _m H _n , where H is hydrogen. X may be a dopant species such as any of those described above. Alternatively, X may also be an atom that does not affect the conductivity of the workpiece 160. For example, where workpiece 160 comprises silicon, X may be a Group 4 element such as silicon and germanium.

In other words, the feed gas may be BF ₃ or B ₂ F ₄ , while the diluent gas may be, for example, PH ₃ , SiH ₄ , NH ₃ , GeH ₄ , B ₂ H ₆ , or AsH ₃ . These lists represent some possible species that may be used. It should be understood that other feed gas species and diluent species are also possible.

By combining the feed gas and the diluting gas, the deleterious effects of the fluorine ions can be reduced. For example, without being limited to any particular theory, the introduction of hydrogen can produce films or coatings on the dielectric window 125. This contributes to protecting the dielectric window 125, which reduces the amount of contaminants that result from the dielectric window 125 contained within the ion beam 180 being extracted. In addition, the diluent gas may coat the inner surfaces of the plasma chamber walls 107, which may be other sources of contaminants. This coating can reduce the interaction between the fluorine ions and the inner surfaces of the plasma chamber walls 107, which reduces the amount of contaminants produced.

The introduction of a diluting gas can reduce the generation of contaminants and their inclusion in the ion beam. Conversely, the introduction of a large amount of diluent gas can negatively affect the generation of dopant ions to be used in the ion beam. For example, the introduction of an excessive amount of diluent gas may reduce the dopant beam current produced by the ion source. Additionally, an excessive amount of diluent gas, including hydrogen, can cause etching and hence additional contamination. Hydrogen is known to etch certain materials. For example, hydrogen can react with graphite walls, which results in the generation of CH _x gas.

Surprisingly, it was determined that the contaminant reduction did not decrease proportionally with increasing diluent concentration. In other words, when the amount of diluent increases above a certain threshold, the ratio of contaminant current to dopant current actually increases. This may be caused by the fact that, above certain thresholds, the additional coating on the inner surfaces of the plasma chamber walls 107 provides little or no additional protection for the fluoride ions. In addition, plasma parameters such as high plasma potential will be altered with a high percentage of diluent gas, which can cause additional sputtering of chamber walls by diluent gas ions. In addition, a high dilution gas percentage can cause etching of the wall material, thus adding contaminants. Additional sputtering of the chamber walls may result in increased contaminant levels. Thus, if the dopant current decreases as a function of the diluent concentration and the contaminant concentration remains constant or increases after a certain threshold, the percentage of contaminants in the ion beam necessarily increases.

Figure 2 shows an exemplary graph showing the effects of dilute gas concentration on both the dopant beam current and percent of contaminants as compared to the dopant in the ion beam. As discussed above, the contaminant can be an ion species containing silicon, nitrogen, oxygen, hydrogen, aluminum, carbon, carbon-based compounds, fluorine, fluorine-based compounds, or other non- .

As can be seen in FIG. 2, the dopant current represented by the bar graph is maximum when no diluent is present. In this example, depending on the concentration of the diluted GeH ₄ gas is increased, there is an almost linear decrease of the dopant current. It should be noted that although these graphs show a particular relationship between the dopant current and the diluent concentration, this relationship may be unique to the test conditions used. For example, different diluent gases, different RF power levels, or different pressures (or flow rates) within the plasma chamber can produce different results. Thus, this bar graph is intended to show the general trend between dopant current and diluent concentration.

Line 300 shows a measurement of beam impurities defined as a percentage of a particular contaminant as compared to the dopant in the ion beam, wherein the contaminant may be one of those identified above. As expected, the beam impurity decreases as the diluent concentration increases from 0% to 10%. As mentioned above, this can be attributed to the coating action of hydrogen in the diluent gas. It may be possible that other paper in the diluent gas may affect the coating action. For example, in the case of GeH ₄ , the hydrogen molecules are light and thus can be quickly pumped out. However, GeH ₄ is a heavier molecule with attached hydrogen, and therefore may have a long residence time and high probability to react with and coat the chamber surfaces. For example, compounds having the composition GeH _x can coat the walls, thereby protecting the wall material from fluorine etching. However, unexpectedly, the beam impurity remains relatively flat until the diluent concentration reaches about 30%. In other words, despite the introduction of more diluent gas, the amount of contaminant remains relatively constant with respect to the amount of dopant. Over a range of about 5% to 30%, the beam impurity is less than about 1%. Surprisingly, if the diluent concentration is increased by more than about 30%, the beam impurities increase dramatically and reach a level exceeding 5% if the gas mixture is a 60% diluent gas. The beam impurity can be minimized when the concentration of diluent gas is between 5% and 30%.

1A through 1C use an ion source having an RF antenna 120 and an RF power supply for generating necessary ions. However, it will be appreciated that other ion sources may be used, including IHC, hollow-cathode, helicon, and microwave ion sources. For example, an indirectly heated cathode (IHC) that uses heat to cause thermal ion emission of electrons may also be used in some embodiments. Other ion sources are also within the scope of this disclosure.

Thus, by using two source gases, an extracted ion beam 180 with reduced beam impurity can be generated. The first source gas, or feed gas, may be a species containing both boron and fluorine, such as BF ₃ or B ₂ F ₄ . The second source gas, or diluent, can be either silicon or germanium, such as silane (SiH ₄ ) or germane (GeH ₄ ), and hydrogen containing species. These two source gases are introduced simultaneously or sequentially into the chamber 105 of the ion source 100 where they are ionized. The ion source may use RF energy generated by the RF antenna 120. In another embodiment, the ion source can use thermal ion emission of electrons using IHC. Other methods of ionizing the gas may also be used by the ion source. These two source gases can be introduced such that between 5% and 30% of the total gas (by volume) becomes the diluent gas and the remainder is the feed gas. Ions from both source gases are extracted through openings 140 through the use of electrodes 130 and 150 and accelerated toward workpiece 160 where they are injected into workpiece 160 . As described above, these ions may not be mass analyzed, meaning that all of the extracted ions are injected into the workpiece 160.

In another example, the diluent gas may comprise a dopant having an opposite conductivity. For example, the first source gas, or feed gas, may be a species containing both boron and fluorine, such as BF ₃ or B ₂ F ₄ . The second source gas, or diluent, may be a Group 5 element such as phosphorus, nitrogen or arsenic and a species containing hydrogen.

The above discussion discusses diluents ranging between about 5% and 30% of the total volume of gas. However, in some embodiments, this range may be different. For example, in some embodiments, the diluent concentration can amount to 10%, such as 1-10%, 2-10%, 3-10%, or 5-10%. In another embodiment, the diluent concentration can amount to 15%, such as 1-15%, 2-15%, 3-15%, 5-15%, or 7-15%. In another embodiment, the diluent concentration can reach 20%, such as 2-20%, 3-20%, 5-20%, 7-20%, or 10-20%. In another embodiment, the diluent concentration can amount to 30%, such as 3-30%, 5-30%, 7-30%, 10-30%, or 15-30%. In another embodiment, the diluent concentration can reach 40%, such as 3-40%, 5-40%, 7-40%, 10-40%, 15-40%, or 20-40%. In other embodiments, the diluent concentration can amount to 50%, such as 5-50%, 7-50%, 10-50%, 15-50%, 20-50%, or 25-50%. Finally, in another embodiment, the diluent concentration may range from 60%, such as 5-60%, 7-60%, 10-60%, 15-60%, 20-60%, 25-60%, or 30-60% % ≪ / RTI >

The above description details the use of a diluting gas with the feed gas to produce the plasma used to generate the ions to be injected into the workpiece using the non-mass analyzed ion beam. However, other techniques may also be used in addition to or instead of this method.

For example, in one embodiment, the inner surfaces of the plasma chamber walls 107 of the ion source 100 may be conditioned prior to the implantation process. Conditioning is a process in which the material is coated onto the inner surfaces of these plasma chamber walls 107. This material can contribute to protecting the plasma chamber walls 107 from the harmful effects of halogens, which reduces the amount of contaminants introduced into the ion beam that are etched and extracted from these plasma chamber walls 107.

Conditioning can be performed in a number of ways. In the first embodiment, conditioning is performed in the same manner as implantation. In other words, the plasma is generated in the chamber 105 using energy from the RF antenna 120 or other plasma generator. Ions from the plasma are then extracted from the chamber 105 through the application of bias voltages to the electrodes 130,150. During this time, ions from the unextracted plasma may be deposited on the dielectric window 125 as well as the plasma chamber walls 107 of the chamber 105.

In the second embodiment, bias voltages are not applied to the electrodes 130,150. In this manner, the plasma and ions remain in the chamber 105. Again, ions from the plasma can be deposited on the plasma chamber walls 107 of the chamber 105.

In each embodiment, the generation of this plasma produces ions, some of which adhere to the inner surface of the plasma chamber walls 107, which creates a coating on these surfaces. This conditioning process can be performed for about 60 minutes, but the amount of time is not limited by this disclosure. In other embodiments, such a conditioning process may be performed until a coating of a certain thickness is produced.

In some embodiments, a hydride containing the desired dopant species is used to condition the plasma chamber walls 107. The dopant species desired may be a dopant to be used during the subsequent implantation process. In other words, in scenarios where the feed gas comprises boron to be injected into the workpiece during the injection process, borane can be used as the conditioning gas during the conditioning process. Such borane can be diborane (B ₂ H ₆ ), pentaborene (B ₅ H ₉ ), decaborane (B ₁₀ H ₁₄ ), or any other borane. If different dopants are to be injected, different hydrides may be used as the conditioning gas.

In addition, a conditioning co-gas can be used with these hydrides. In some embodiments, the conditioning co-gas may be an inert gas, such as helium, argon, krypton, or xenon. In other embodiments, conditioning co- gas may be a hydride containing a Group 4 element, such as, but not limited to, silicon (i.e., silane, SH ₄₎ or germanium (that is, germane, GH _4). In yet other embodiments, the conditioning co-gas may be a hydride containing a conductive species opposite the desired dopant. In other words, if the feed gas contains boron, a hydride containing a Group 5 element may be used as the conditioning co-gas. In such a scenario, the conditioning co-gas may be phosphine (PH ₃ ) or arsine (AsH ₃ ).

The amount of conditioning co-gas can be varied. For example, in some embodiments, the conditioning co-gas may be between 10-40% of the total gas introduced into the chamber 105. In other embodiments, the conditioning co-gas may be between 20-40% of the total gas. In yet other embodiments, the conditioning co-gas may be about 30% of the total gas introduced during the conditioning process.

In a particular example, BF ₃ or B ₂ F ₄ is used as the feed gas for injecting the workpiece. In order to condition the plasma chamber walls 107 of the ion source 100, diborane may be used with the conditioning nose-gas. Such conditioning co-gases include, for example, inert gases such as helium, argon, krypton or xenon; A _quaternary hydride such as SH ₄ or GeH ₄ ; Or a 5-membered hydride such as PH ₃ or AsH ₃ . Of course, this list is not exhaustive, and other molecules can be used as conditioning co-gases during the conditioning process.

Surprisingly, the addition of the conditioning co-gas during the conditioning process greatly affects the quality of the subsequent injection. For example, in one test, the conditioning process was performed on an ion source using only diborane as the conditioning gas. This conditioning was carried out for 1 hour. After conditioning, a feed gas such as B ₂ F ₄ was used with RF power of about 3 KW to generate the plasma in the chamber 105, and the workpieces were implanted with a boron-based ion beam. Additionally, 10% of the total gas introduced during the injection process was diluted gas containing GeH _4. For this test, an extraction energy of 10 keV was used. While the workpiece was being injected, an analysis of the ion beam was performed. After less than 2 hours of injection with B ₂ F ₄ using 10% GeH ₄ as the diluting gas, it was found that the contaminant exceeded 1% as a percentage of the total beam current. This can be confirmed graphically at A of FIG. 3 where line 400 represents the percentage of contaminants in the ion beam. Contaminants include, but are not limited to, carbon, nitrogen, oxygen, fluorine, aluminum, and compounds containing any of these elements.

In the second test, conditioning was performed using a combination of conditioning gas (diborane) and conditioning co-gas (germane). This conditioning was also carried out for 1 hour. Again, after conditioning, a feed gas, such as B ₂ F ₄ , was used with a 10% GeH ₄ dilution gas to produce a plasma within the chamber 105, and the workpieces were implanted with a boron-based ion beam. While the workpiece was being injected, an analysis of the ion beam was performed. Unlike the first results, in this case, even after 9 hours of continuous operation, the level of contaminants was still less than 1% of the total beam current. This is graphically illustrated in Figure 3B, where line 410 represents the percentage of contaminants in the ion beam.

In operation, a conditioning cycle is first performed to coat the plasma chamber walls 107 of the ion source 100 with a material. As described above, in some embodiments, the coating is a boron-based material that is produced by introducing a boron such as diborane into the chamber 105. These conditioning gases are then activated by the plasma, and ions from the plasma adhere to and coat the plasma chamber walls 107 of the chamber 105. As described above, in order to improve the quality and thickness of the conditioning process, a conditioning co-gas can be used with borane. Such a conditioning co-gas may be an inert gas such as helium, argon, krypton or xenon. In other embodiments, such a conditioning co-gas may be a hydride containing a Group 5 element such as PH ₃ or AsH ₃ . In other embodiments, such a conditioning co-gas may be a hydride of a Group 4 element. Such a conditioning co-gas can be introduced at least partially into the boron.

This conditioning process contributes to coating the plasma chamber walls 107 such that impurities and other contaminants found in the plasma chamber walls 107 are separated from the plasma. Such a coating contains a dopant that is found in a conditioning gas, which may be a Group III element such as boron. The coating may also include Group 4 elements such as germanium or silicon; Or molecules found in a conditioning co-gas such as Group 5 elements such as phosphorus or arsenic. A coating of sufficient thickness may be applied. The duration of the conditioning procedure may be based on the elapsed time, such as a 1-hour conditioning cycle, or it may be based on the measured thickness of the coating as the coating is deposited on the plasma chamber walls 107.

The gases supplied to the chamber 105 are then changed to gases to be used during the injection process. In particular, feed gas is introduced. The conditioning gas and conditioning co-gas may or may not be continuously introduced into the chamber 105. As described above, this feed gas can be a dopant and a fluorine containing molecule such as BF ₃ or B ₂ F ₄ , but other gases can also be used. It should be noted that the dopant used in the implantation process may be the same as described above in connection with the conditioning process. Additionally, a diluent gas may be supplied to the chamber 105 during the injection process. Such a diluent gas may be, without limitation, a hydride containing a Group III, Group IV, or Group 5 element such as B ₂ H ₆ , GeH ₄ , SH ₄ , PH ₃ , and AsH ₃ . As mentioned above, in the scenario where the desired dopant species is a Group 3 element, the diluent gas may comprise Group 4 or Group 5 elements. In some embodiments, the diluent gas and the conditioning co-gas may be the same gas. In other embodiments, the dilution gason and the conditioning gas may be the same gas. In still other embodiments, the diluent gas may comprise both a conditioning gas and a conditioning co-gas. Then, the injection gases are activated by plasma and extracted by applying a bias voltage to the electrodes 130. The extracted ions are then directed toward the workpiece, where the ions are injected first without being mass analyzed.

This implantation process is used for a plurality of workpieces 160 and may be continued for a specific time period or may be terminated when the level of contaminants in the extracted ion beam reaches a predetermined level. For example, the implantation process may continue until the level of contaminants reaches about 1% of the total beam current, but other levels of contamination may be selected. Figures 4A-4B show a comparison of two conditioning procedures. In the first embodiment shown in Fig. 4A, conditioning is carried out using only diborane as the conditioning gas. Conditioning is performed for one hour, and then an infusion process is initiated. The injection process ends when the level of contaminants reaches a predetermined level, e.g., 1%. As can be seen, this results in a duty cycle of about 50%, where an amount of time approximately equal to the time required to inject the workpieces is required to condition the chamber 105. In the second embodiment shown in Fig. 4B, conditioning is performed using a conditioning co-gas, which may be trivial in this example with diborane. As shown in Figure 3B, this combination resists the deleterious effects of halogen and allows longer injection times. In this particular example, the conditioning process was performed for one hour, and then the infusion process was performed for about nine hours. After 9 hours, the level of contaminants was below a predetermined level. In other words, in this particular embodiment, the duty cycle defined as the required injection time divided by the total time is about 90%. This difference in duty cycle is very large. In other words, for a period of 10 days, at a duty cycle of 90%, the injection will be performed for about 216 hours. In contrast, using a 50% duty cycle would take 18 days to achieve the same duration of injection. This directly translates into operating efficiency and the cost of each workpiece. These examples are illustrative, and the results may differ depending on the choice of different gases and / or implant energies.

The ability to use these various gases and nose gases in an ion implantation system that does not use mass spectrometry is surprising because all of the ions generated in the chamber 105 are ultimately injected into the workpiece. The ability to use species other than the dopant species during both the conditioning process and the infusion process, without adversely affecting the workpiece, is unpredictable.

This disclosure is not to be limited in scope by the specific embodiments described herein. Rather, in addition to the embodiments described herein, various other embodiments of the disclosure and modifications thereto will be apparent to those skilled in the art from the foregoing description and accompanying drawings. Accordingly, these other embodiments and modifications are intended to fall within the scope of the present disclosure. Further, although the present disclosure has been described herein in the context of certain embodiments in a particular environment for a particular purpose, those skilled in the art will appreciate that the benefit of this disclosure is not so limited, and that the disclosure may be applied to any number of environments As will be appreciated by those skilled in the art. Accordingly, the claims set forth below should be construed in light of the full breadth and spirit of this disclosure, as set forth herein.

Claims (14)

CLAIMS What is claimed is: 1. A method of processing a workpiece,
Introducing a conditioning gas into a chamber of an ion source, wherein the conditioning gas comprises a hydride and a conditioning co-gas containing a desired dopant species, the conditioning nose gas An inert gas, a hydride of a Group 4 element, or a hydride of a conductivity species opposite the desired dopant species, wherein between 10% and 40% of the total volume of the introduced gas comprises the conditioning nose gas Comprising;
Ionizing the conditioning gas and the conditioning nose gas in the chamber to form a coating on the walls of the chamber;
Modifying the gases introduced into the chamber after the coating is formed and introducing feedgas into the chamber, wherein the feed gas comprises fluorine and the desired dopant species;
Ionizing the feed gas in the chamber to produce ions; And
Extracting the ions from the chamber and accelerating the ions toward the workpiece so that the ions can be injected into the workpiece without mass analysis.
The method according to claim 1,
Wherein the desired dopant species comprises boron.
The method of claim 2,
Wherein the conditioning nose gas comprises a hydride of a Group 4 element.
The method of claim 2,
Wherein the conditioning nose gas comprises a hydride of a Group 5 element.
The method of claim 2,
Wherein the conditioning nose gas comprises an inert gas.
CLAIMS What is claimed is: 1. A method of processing a workpiece,
Introducing a conditioning gas into a chamber of an ion source, wherein the conditioning gas comprises a borane and a conditioning nose gas, the conditioning nose gas comprising a hydride of a Group 4 or Group 5 element, step;
Forming a coating on the walls of the chamber, wherein the coating comprises a Group 4 or Group 5 element and boron;
Introducing a feed gas into the chamber after the coating is formed, the feed gas comprising fluorine and boron;
Ionizing the feed gas in the chamber to produce ions; And
Extracting the ions from the chamber and accelerating the ions toward the workpiece.
The method of claim 6,
Wherein the ions are injected into the workpiece without mass analysis.
The method of claim 6,
A diluent gas is introduced into the chamber together with the feed gas, wherein the diluent gas comprises a hydride of a Group 4 or Group 5 element,
The method further comprising the step of ionizing the diluent gas with the feed gas in the chamber to produce ions.
The method of claim 6,
Wherein the coating is formed by ionizing the conditioning gas and the conditioning nose gas in the chamber.
CLAIMS 1. A method for processing works,
Performing a conditioning process on the chamber of the ion source to coat the walls of the chamber with Group 4 or Group 5 elements and boron; And
Performing a post-implantation process after a coating is formed on the walls, wherein a feed gas comprising fluorine and boron is ionized to produce ions, the ions are extracted from the chamber and accelerated toward the workpiece, Ions are injected into the work without mass analysis.
The method of claim 10,
Wherein the conditioning process comprises ionizing a conditioning gas in the chamber comprising a conditioning gas comprising borane and a hydride of the Group 4 or Group 5 element.
The method of claim 11,
Wherein the conditioning nose gas comprises phosphine (PH ₃ ) or arsine (AsH ₃ ).
The method of claim 11,
Wherein the conditioning nose gas comprises germane (GeH ₄ ) or silane (SiH ₄ ).
The method of claim 10,
The extracted ions form an ion beam,
The method further comprising repeating the conditioning process if the percentage of contaminants in the ion beam exceeds a predetermined threshold.

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