Ion implantation method and related system

Abstract

Methods of ion implantation and related systems are provided herein. The ion implantation method comprises vaporizing a precursor comprising a metal borohydride compound to obtain a vaporized precursor, and contacting the vaporized precursor with a substrate under vapor deposition conditions to form a film on the substrate. The metal borohydride compound isotope is enriched in at least one boron isotope.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the field of ion implantation systems and methods. BACKGROUND

[0002] Precursors for ion implantation involve implanting a chemical into a substrate, such as a microelectronic device wafer, must have sufficient vapor pressure to produce sufficient ion current for deposition. Most metal precursors are solids that contain carbon and require heating. However, carbon-based precursors and heating are preferably avoided to prevent carbon deposition into the ion source beam, which reduces source lifetime. SUMMARY

[0003] Some embodiments relate to an ion implantation method. In some embodiments, the ion implantation method includes vaporizing a precursor including a metal borohydride compound to obtain a vaporized precursor, and contacting the vaporized precursor with a substrate under vapor deposition conditions to form a film on the substrate. In some embodiments, the metal borohydride compound is isotopically enriched in at least one boron isotope.

[0004] Some embodiments relate to a gas supply assembly. In some embodiments, the gas supply assembly includes at least one gas supply container containing a precursor including a metal borohydride compound. In some embodiments, the metal borohydride compound is isotopically enriched in at least one boron isotope. In some embodiments, the at least one gas supply container is configured to vaporize the metal borohydride compound to produce a vaporized precursor for ion implantation into a substrate.

[0005] Some embodiments relate to an ion implantation system. In some embodiments, the ion implantation system includes a gas supply assembly including at least one gas supply container in fluid communication with an ion implantation device. In some embodiments, the at least one gas supply container contains a precursor including a metal borohydride compound. In some embodiments, the metal borohydride compound is isotopically enriched in at least one boron isotope. In some embodiments, the at least one gas supply container is configured to vaporize the metal borohydride compound to produce a vaporized precursor, which is supplied to the ion implantation device for ion implantation into a substrate. BRIEF DESCRIPTION OF DRAWINGS

[0006] Some embodiments of the present disclosure are described herein with reference to the accompanying drawings only by way of example. With specific reference to the drawings in detail, it is stressed that the particulars shown are by way of example and for purposes of illustrative discussion of embodiments of the present disclosure. In this regard, the description taken with the drawings makes apparent to those skilled in the art how embodiments of the present disclosure can be practiced.

[0007] Figure 1 A schematic diagram depicting an ion implantation system, in accordance with some embodiments.

[0008] Figure 2 is a flowchart of a method for ion implantation, in accordance with some embodiments. DETAILED DESCRIPTION

[0009] Among the benefits and improvements that have been disclosed are other objects and advantages that will be apparent to or can be learned by the reader from the following description of the preferred embodiments when considered in connection with the accompanying drawings. The detailed embodiments of the present disclosure set forth herein are described as being illustrative of the present disclosure and not limiting thereof. There is no intention that the present disclosure be limited to such detailed embodiments. Rather, the detailed description is to be regarded as describing what is considered to be a preferred embodiment of the present disclosure and is presented as illustrations of the application claims. Therefore, various changes can be made without departing from the scope or spirit of the present disclosure.

[0010] Any prior patent and publication referred to herein is incorporated by reference in its entirety.

[0011] Throughout this specification and claims, the following terms have the meanings associated with them as explicitly associated, unless the context clearly dictates otherwise. As used herein, the phrases “in one embodiment,” “in an embodiment,” and “in some embodiments” do not necessarily refer to the same embodiment, although they can. In addition, as used herein the phrases “in another embodiment” and “in some other embodiments” do not necessarily refer to a different embodiment, although they can. All embodiments of the present disclosure are intended to be combinable with each other, unless the context clearly dictates otherwise.

[0012] As used herein, the term “based on” is non-exclusive and permits additional factors based on which a determination is made. In addition, throughout this specification, the meaning of “a,” “an,” and “the” include plural references. The meaning of “in” includes “in” and “on.”

[0013] As used herein, the term “contacting” refers to bringing two or more components in close or intimate proximity, or direct contact.

[0014] Some embodiments relate to ion implantation methods and related systems. As disclosed herein, at least one advantage of the present disclosure is that the ion implantation methods (and related systems) disclosed herein are carbon-free and do not require heating in the ion implantation chamber. At least one additional advantage of the present disclosure is that the ion implantation methods (and related systems) disclosed herein surprisingly exhibit longer source life. For example, as disclosed herein, in some embodiments, when the ion implantation methods (and related systems) employ a liquid aluminum precursor (e.g., borohydride aluminum), the ion implantation system exhibits enhanced ion beam current and / or source life.

[0015] Some embodiments relate to precursors and related methods. At least some of these embodiments relate to precursors that can be used to manufacture microelectronic devices, including semiconductor devices and the like. For example, the precursors can be used to form a film by one or more deposition processes. Examples of deposition processes include, but are not limited to, at least one of a chemical vapor deposition (CVD) process, a digital or pulsed chemical vapor deposition process, a plasma-enhanced cyclic chemical vapor deposition process (PECCVD), a flow chemical vapor deposition process (FCVD), an atomic layer deposition (ALD) process, thermal atomic layer deposition, a plasma-enhanced atomic layer deposition (PEALD) process, a metal-organic chemical vapor deposition (MOCVD) process, a plasma-enhanced chemical vapor deposition (PECVD) process, or any combination thereof.

[0016] As mentioned above, the precursors can include any source precursor, including vaporizable precursors. In some embodiments, the precursors include a metal borohydride. In some embodiments, the metal borohydride compound is isotopically enriched in at least one boron isotope.

[0017] As used herein, “isotopically enriched” can refer to boron isotopes. As another example, the at least one boron isotope includes 10 B. As another example, the at least one boron isotope includes 11 B. As another example, the at least one boron isotope includes 10 B and 11 B. As another example, the at least one boron isotope includes 10 B, 11 B, or any combination thereof. Non-limiting examples of isotopically enriched metal borohydride compounds include, but are not limited to, at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof. In some embodiments, the metal borohydride compound is a compound of the following formula:

[0018] M(BH4) n ,

[0019] wherein:

[0020] M is K, Ca, Li, Na, Hf, or Al; and

[0021] n is 0 to 4.

[0022] In some embodiments, the metal borohydride compound can include at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof. In some embodiments, the at least one boron isotope includes 10 B. In some embodiments, the at least one boron isotope includes11 B. In some embodiments, the at least one boron isotope comprises 10 B and 11 B. As another example, the at least one boron isotope comprises 10 B, 11 B or any combination thereof.

[0023] In some embodiments, the purity of the metal borohydride compound is at least 90%. In some embodiments, the purity of the metal borohydride compound is at least 91%, 92%, 93%, 94%, 95%, 96%, 97%, 98%, 99%, 99.9%, 99.99%, 99.999%, or 99.9999%. In some embodiments, the purity of the metal borohydride compound is 100%.

[0024] In some embodiments, the precursor is present in a liquid phase.

[0025] In some embodiments, the precursor is vaporized at a temperature of 20 °C to 50 °C. In some embodiments, the precursor is vaporized at a temperature of 25 °C to 50 °C, 26 °C to 50 °C, 27 °C to 50 °C, 28 °C to 50 °C, 29 °C to 50 °C, 30 °C to 50 °C, 31 °C to 50 °C, 32 °C to 50 °C, 33 °C to 50 °C, 34 °C to 50 °C, 35 °C to 50 °C, 36 °C to 50 °C, 37 °C to 50 °C, 38 °C to 50 °C, 39 °C to 50 °C, 40 °C to 50 °C, 41 °C to 50 °C, 42 °C to 50 °C, 43 °C to 50 °C, 44 °C to 50 °C, 45 °C to 50 °C, 46 °C to 50 °C, 47 °C to 50 °C, 48 °C to 50 °C, or 49 °C to 50 °C. In some embodiments, the precursor is vaporized at a temperature of 20 °C to 49 °C, 20 °C to 48 °C, 20 °C to 47 °C, 20 °C to 46 °C, 20 °C to 45 °C, 20 °C to 44 °C, 20 °C to 43 °C, 20 °C to 42 °C, 20 °C to 41 °C, 20 °C to 40 °C, 20 °C to 39 °C, 20 °C to 38 °C, 20 °C to 37 °C, 20 °C to 36 °C, 20 °C to 35 °C, 20 °C to 34 °C, 20 °C to 33 °C, 20 °C to 32 °C, 20 °C to 31 °C, 20 °C to 30 °C, 20 °C to 29 °C, 20 °C to 28 °C, 20 °C to 27 °C, 20 °C to 26 °C, 20 °C to 25 °C, 20 °C to 24 °C, 20 °C to 23 °C, 20 °C to 22 °C, or 20 °C to 21 °C.

[0026] In some embodiments, the precursor is vaporized at a temperature of 20°C to 25°C. In some embodiments, the precursor is vaporized at a temperature of 21°C to 25°C, 22°C to 25°C, 23°C to 25°C, or 24°C to 25°C. In some embodiments, the precursor is vaporized at a temperature of 20°C to 24°C, 20°C to 23°C, 20°C to 22°C, or 20°C to 21°C.

[0027] In some embodiments, the precursor is vaporized at a pressure of 100 to 800 Torr. In some embodiments, the precursor is vaporized at pressures of 150 to 800 Torr, 200 to 800 Torr, 250 to 800 Torr, 300 to 800 Torr, 350 to 800 Torr, 400 to 800 Torr, 450 to 800 Torr, 500 to 800 Torr, 550 to 800 Torr, 600 to 800 Torr, 650 to 800 Torr, 700 to 800 Torr, or 750 to 800 Torr. In some embodiments, the precursor is vaporized at pressures of 100 to 750 Torr, 100 to 700 Torr, 100 to 650 Torr, 100 to 600 Torr, 100 to 550 Torr, 100 to 500 Torr, 100 to 450 Torr, 100 to 400 Torr, 100 to 350 Torr, 100 to 300 Torr, 100 to 250 Torr, 100 to 200 Torr, or 100 to 150 Torr.

[0028] In some embodiments, the precursor is vaporized at a pressure of 740 Torr to 780 Torr. In some embodiments, the precursor is vaporized at a pressure of 740 Torr to 780 Torr, 745 Torr to 780 Torr, 750 Torr to 780 Torr, 755 Torr to 780 Torr, 760 Torr to 780 Torr, 765 Torr to 780 Torr, 770 Torr to 780 Torr, or 775 Torr to 780 Torr. In some embodiments, the precursor is vaporized at a pressure of 740 Torr to 775 Torr, 740 Torr to 770 Torr, 740 Torr to 765 Torr, 740 Torr to 760 Torr, 740 Torr to 755 Torr, 740 Torr to 750 Torr, or 740 Torr to 745 Torr.

[0029] In some embodiments, the precursor or vaporized precursor further comprises H2.

[0030] In some embodiments, the precursor or vaporized precursor further comprises at least one of BF3, BH3, B2H6, or any combination thereof.

[0031] Figure 1Schematic diagrams of ion implantation systems according to some embodiments are depicted. In some embodiments, the gas component supplied from at least one gas supply container 102 to an arc chamber 150 for implantation into a substrate contains a precursor comprising a metal borohydride compound. In some embodiments, the metal borohydride compound is an isotope enriched with at least one boron isotope. In some embodiments, at least one gas supply container 102 is configured to vaporize the metal borohydride compound to generate a vaporized precursor for ion implantation into the substrate.

[0032] In some embodiments, the metal borohydride compound of the gas supply assembly and / or at least one gas supply container 102 includes at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof. In some embodiments, at least one boron isotope includes... 10 B 11 B or at least one of the following combinations:

[0033] In some embodiments, at least one gas supply container 102 is a single container. In some embodiments, at least one gas supply container 102 includes two or more containers. In some embodiments, at least one gas supply container 102 includes at least one of a first container, a second container, a third container, a fourth container, or any combination thereof. It will be understood that any of the at least one gas supply container 102 disclosed herein may further include other gases and / or materials, such as (e.g., but not limited to) at least one of ionizable gases, diluent gases, carrier gases, auxiliary gases, the like, or any combination thereof. In some embodiments, the gas supply container 102 includes a single container containing a precursor. In some embodiments, the precursor includes a metal borohydride compound. In some embodiments, the metal borohydride compound is isotopically enriched.

[0034] In some embodiments, individual containers among one or more containers include more than one dopant gas, such that the container includes a mixture of dopant gases. In some embodiments, gas supply container 102 is configured to deliver dopant gas below atmospheric pressure via one or more pressure regulators. In some embodiments, the dopant gas is delivered below atmospheric pressure using an absorbent.

[0035] In some embodiments, the arc chamber 150 includes an arc chamber wall having a surface facing the internal plasma. One or more arc chamber liners may be present, all or a portion of the surface of the arc chamber 150 wall facing the internal plasma, configured to contact the internal plasma.

[0036] like Figure 1As shown, the gas supply container 102 may have an internal volume for containing a precursor comprising a metal borohydride compound for ion implantation into a substrate 128 in the illustrated ion implantation chamber 101. In some embodiments, the metal borohydride compound is isotopically enriched with at least one boron isotope. In some embodiments, the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof. In some embodiments, the at least one boron isotope comprises 10 B 11 B or at least one of the following combinations:

[0037] The storage and gas supply container 102 may be of the type containing an adsorption medium on which the dopant gas is physically adsorbed to store the gas, wherein the gas is desorbed from the adsorption medium under application conditions to be discharged from the gas supply container 102. The adsorption medium may be a solid-phase carbon adsorbent material. This type of adsorbent-based container is available from Interg Inc. (Danbury, Connecticut, USA, under the trademarks SDS and SAGE). Alternatively, the container may be of the internal pressure regulating type, containing one or more pressure regulators within the internal volume of the container. Such pressure regulating containers are available from Interg Inc. (Danbury, Connecticut, USA, under the trademark VAC). As a further alternative, the container may contain a dopant source material in solid form, which is vaporized, for example, by heating the container and / or its contents to produce a dopant gas as a vaporization or sublimation product.

[0038] The storage and gas supply container 102 may include a cylindrical container wall 104 that surrounds the internal volume containing the metal borohydride compound or mixture thereof in an adsorbed, free gas, or liquefied gas state.

[0039] The gas supply container 102 may include a valve head 108 coupled in gaseous communication via a dispensing line 117. A pressure sensor 110 may be housed in the line 117 together with a mass flow controller 114; other optional monitoring and sensing components may be coupled to the line and interface with control components (e.g., actuators, feedback and computer control systems, cyclic timers, etc.).

[0040] The ion implantation chamber 101 may contain an ion source 116 that receives a pre-treatment agent from line 117 and generates an ion beam 105. The ion beam 105 passes through a mass analyzer unit 122, which selects desired ions and rejects unselected ions.

[0041] Selected ions can pass through an accelerating electrode array 124 and then through a deflecting electrode 126. The resulting focused ion beam can be used to impinge on a substrate element 128, which is mounted on a rotatable holder 130 mounted on a spindle 132. The ion beam of dopant ions can be used to form a doped structure according to the desired doping substrate.

[0042] The corresponding sections of the ion implantation chamber 101 can be emptied through pipelines 118, 140 and 144 by means of pumps 120, 142 and 146 respectively.

[0043] Figure 2 This is a flowchart of a method 200 for ion implantation according to some embodiments.

[0044] like Figure 2 As shown, method 200 may include one or more of the following steps: step 202, vaporizing a precursor comprising a metal borohydride compound to obtain a vaporized precursor; and step 204, contacting the vaporized precursor with a substrate under vapor deposition conditions to form a film on the substrate. In some embodiments, the metal borohydride compound isotope enriched with at least one boron isotope. In some embodiments, the metal borohydride compound includes at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof. In some embodiments, at least one boron isotope includes 10 B 11 B or at least one of the following combinations:

[0045] In some embodiments, the vaporization of step 202 includes heating the precursor, sputtering the precursor with a reactive gas, vaporizing the precursor at a certain pressure, or vaporizing the precursor at a certain pressure and temperature.

[0046] In some embodiments, the arc chamber in step 202 may be an arc chamber 150 as described herein. The gas component may include a precursor as described herein for a gas supply container 102.

[0047] In some embodiments, the contact in step 204 includes reacting the vaporized precursor with the substrate. In some embodiments, the contact includes mixing the vaporized precursor with the substrate. In some embodiments, the contact includes absorbing the vaporized precursor on the substrate. In some embodiments, the contact includes combining the vaporized precursor with the substrate. In some embodiments, the contact is performed under gas phase conditions. In some embodiments, the contact forms a film on the substrate.

[0048] It will be understood that any one or more of the embodiments disclosed herein may be used alone or in combination without departing from the scope of this disclosure.

[0049] Aspect

[0050] The following describes various aspects. It should be understood that any one or more of the features listed in (several) of the following aspects may be combined with any one or more other aspects.

[0051] Aspect 1. An ion implantation method, comprising:

[0052] Vaporization involves obtaining vaporized precursors from metal borohydride compounds.

[0053] The metal borohydride compound is isotopically enriched with at least one boron isotope; and

[0054] The vaporized precursor is brought into contact with the substrate under vapor deposition conditions to form a film on the substrate.

[0055] Aspect 2. The method according to aspect 1, wherein the metal borohydride compound is a compound of the following formula:

[0056] M(BH4) x ,

[0057] in:

[0058] M is K, Ca, Li, Na, Hf, or Al; and

[0059] n is between 0 and 4.

[0060] Aspect 3. The method according to any one of Aspects 1 to 2, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

[0061] Aspect 4. The method according to any one of aspects 1 to 3, wherein the at least one boron isotope comprises 10 B.

[0062] Aspect 5. The method according to any one of aspects 1 to 4, wherein the at least one boron isotope comprises 11 B.

[0063] Aspect 6. The method according to any one of aspects 1 to 5, wherein the at least one boron isotope comprises 10 B and 11 B.

[0064] Aspect 7. The method according to any one of aspects 1 to 6, wherein the purity of the metal borohydride compound is at least 90%.

[0065] Aspect 8. The method according to any one of aspects 1 to 7, wherein the precursor exists in a liquid phase.

[0066] Aspect 9. The method according to any one of aspects 1 to 8, wherein the precursor is vaporized at a temperature of 20°C to 50°C.

[0067] Aspect 10. The method according to any one of aspects 1 to 9, wherein the precursor is vaporized at a temperature of 20°C to 25°C.

[0068] Aspect 11. The method according to any one of aspects 1 to 10, wherein the precursor is vaporized at a pressure of 100 Torr to 800 Torr.

[0069] Aspect 12. The method according to any one of aspects 1 to 11, wherein the precursor is vaporized at a pressure of 740 Torr to 780 Torr.

[0070] Aspect 13. The method according to any one of aspects 1 to 12, wherein the precursor further comprises H2.

[0071] Aspect 14. The method according to any one of aspects 1 to 13, wherein the precursor further comprises at least one of BF3, BH3, B2H6, or any combination thereof.

[0072] Aspect 15. A gas supply assembly comprising:

[0073] At least one gas supply container contains a precursor including a metal borohydride compound.

[0074] The metal borohydride compound is isotopically enriched with at least one boron isotope;

[0075] The at least one gas supply container is configured to vaporize the metal borohydride compound to generate a vaporized precursor for ion implantation into the substrate.

[0076] Aspect 16. The gas supply assembly according to aspect 15, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

[0077] Aspect 17. The gas supply assembly according to any one of aspects 15 to 16, wherein the at least one boron isotope comprises 10 B 11 B or at least one of the following combinations:

[0078] Aspect 18. An ion implantation system comprising:

[0079] A gas supply assembly comprising at least one gas supply container in fluid communication with an ion implantation device.

[0080] The at least one gas supply container contains a precursor comprising a metal borohydride compound;

[0081] The metal borohydride compound is isotopically enriched with at least one boron isotope;

[0082] The at least one gas supply container is configured to vaporize the metal borohydride compound to produce a vaporized precursor, which is supplied to the ion implantation device for ion implantation into the substrate.

[0083] Aspect 19. The ion implantation system according to aspect 18, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

[0084] Aspect 20. An ion implantation system according to any one of aspects 18 to 19, wherein said at least one boron isotope comprises 10 B 11 B or at least one of the following combinations:

[0085] It should be understood that variations may be made in details, particularly in the construction materials used and the shape, size, and arrangement of components, without departing from the scope of this disclosure. This specification and the described embodiments are examples, wherein the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. An ion implantation method, comprising: Vaporization involves obtaining vaporized precursors from metal borohydride compounds; The metal borohydride compound isotopes are enriched with at least one boron isotope; and The vaporized precursor is brought into contact with the substrate under vapor deposition conditions to form a film on the substrate.

2. The method according to claim 1, wherein the metal borohydride compound is a compound of the following formula: M(BH4) n , in: M is K, Ca, Li, Na, Hf, or Al; and n is between 0 and 4.

3. The method according to claim 1, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

4. The method according to claim 1, wherein the at least one boron isotope comprises 10 B.

5. The method according to claim 1, wherein the at least one boron isotope comprises 11 B.

6. The method according to claim 1, wherein the at least one boron isotope comprises 10 B and 11 B.

7. The method according to claim 1, wherein the purity of the metal borohydride compound is at least 90%.

8. The method according to claim 1, wherein the precursor exists in the liquid phase.

9. The method of claim 1, wherein the precursor is vaporized at a temperature of 20°C to 50°C.

10. The method of claim 1, wherein the precursor is vaporized at a temperature of 20°C to 25°C.

11. The method of claim 1, wherein the precursor is vaporized at a pressure of 100 Torr to 800 Torr.

12. The method of claim 1, wherein the precursor is vaporized at a pressure of 740 Torr to 780 Torr.

13. The method of claim 1, wherein the precursor further comprises H2.

14. The method of claim 1, wherein the precursor further comprises at least one of BF3, BH3, B2H6, or any combination thereof.

15. A gas supply assembly comprising: At least one gas supply container contains a precursor including a metal borohydride compound. The metal borohydride compound isotopes are enriched with at least one boron isotope; The at least one gas supply container is configured to vaporize the metal borohydride compound, thereby generating a vaporized precursor for ion implantation into the substrate.

16. The gas supply assembly of claim 15, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

17. The gas supply assembly of claim 15, wherein the at least one boron isotope comprises 10 B. 11 B or at least one of the following combinations:

18. An ion implantation system comprising: A gas supply assembly comprising at least one gas supply container in fluid communication with an ion implantation device. The at least one gas supply container contains a precursor comprising a metal borohydride compound; The metal borohydride compound isotopes are enriched with at least one boron isotope; The at least one gas supply container is configured to vaporize the metal borohydride compound to produce a vaporized precursor, which is supplied to the ion implantation device for ion implantation into the substrate.

19. The ion implantation system of claim 18, wherein the metal borohydride compound comprises at least one of KBH4, Ca(BH4)2, LiBH4, NaBH4, Hf(BH4)4, Al(BH4)3, or any combination thereof.

20. The ion implantation system of claim 18, wherein the at least one boron isotope comprises 10 B. 11 B or at least one of the following combinations:

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