Reactors, systems including reactors, and methods of making and using same

Abstract

To provide a reactor for processing substrates, and methods for manufacturing and using the reactor.SOLUTION: A reactor 100 comprises a reaction chamber 110, a susceptor 120, and a showerhead 130 or other suitable gas distribution structure. The showerhead / gas distribution structure 130 disperses gas precursors that come from a remote plasma unit 140. The susceptor 120 holds a substrate 150 to be processed. The reactor also comprises a first gas source 160 and a second gas source 170. The first gas source 160 and the second gas source 170 feed a gas to the remote plasma unit 140, and additionally or alternatively provide gas(es) directly to the reaction chamber 110 without the gas(es) passing through the remote plasma unit 140.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE This disclosure relates generally to gas phase systems, reactors, and methods. More particularly, this disclosure relates to gas phase reactors, systems, and methods that can be used in the production of devices, such as semiconductor devices. [Background technology]

[0002] Semiconductor device fabrication can include dry etching processes in substrate processing reactors. The dry etching process may include, for example, exposing the substrate to bombardment of ions generated by a reactive gas. The reactive gas may include a halide chemical, such as a gas having fluoride or chloride atoms. The dry etching process may utilize a remote or direct plasma to activate the reactive gas (e.g., to form ions and / or other reactive species).

[0003] Substrates may have corrosion-resistant materials, such as transition metal nitrides, transition metal oxides, or transition metal carbides, that are etched during dry etching processes. These corrosion-resistant materials may require highly reactive etching gases to react with the corrosion-resistant materials. During the etching process, the highly reactive gases may not only etch material from the substrate, but may also react with the walls of the substrate processing reactor. This may result in the formation and deposition of contaminants on the substrate being processed. Contamination problems may increase when the reactor operates at higher temperatures and / or with certain chemicals.

[0004] As a result, reactors, systems, and methods that mitigate or reduce contaminants on substrates are desirable. Summary of the Invention

[0005] Various embodiments of the present disclosure provide improved systems, reactors, and methods for processing substrates in a reactor. While various drawbacks of the prior art are discussed in more detail below, in general, the systems, reactors, and methods can be used to assemble devices while mitigating contaminants on the surface of the substrate that might otherwise occur.

[0006] According to at least one embodiment of the present disclosure, a system (e.g., a semiconductor processing system) includes a reaction chamber including a first material, a susceptor including a second material and configured to hold a substrate for processing, a gas distribution structure (e.g., a showerhead) including a third material, and a first gas source for providing a first gas precursor to the reaction chamber in a process for etching a film on a substrate, wherein the first material, the second material, and the third material react with one or more of the first gas precursor and the second gas precursor to form (e.g., volatile) gas compounds that can be purged from the reaction chamber.

[0007] According to at least one other embodiment of the present disclosure, a method of forming a semiconductor processing device includes providing a reaction chamber containing a first material; providing a susceptor containing a second material and configured to hold a substrate for processing; providing a gas distribution structure (e.g., a showerhead) containing a third material; and providing a first gas source that provides a first gas precursor to the reaction chamber in a process of etching a film on a substrate, wherein the first material, the second material, and the third material react with one or more of the first gas precursor and the second gas precursor to form (e.g., volatile) gas compounds that can be purged from the reaction chamber.

[0008] Certain objects and advantages of the present invention have been described hereinabove for purposes of summarizing the invention and the advantages achieved over the prior art. Of course, it should be understood that not necessarily all such objects or advantages may be achieved in accordance with any particular embodiment of the invention. Thus, for example, one skilled in the art will recognize that the invention may be embodied or performed in a manner that achieves or optimizes one advantage or group of advantages as taught or suggested herein, without necessarily achieving other objects or advantages as may be taught or suggested herein.

[0009] All of these embodiments are intended to be within the scope of the invention disclosed herein. These and other embodiments will be readily apparent to those skilled in the art from the following detailed description of the preferred embodiments, taken in conjunction with the accompanying drawings, and the invention is not limited to any particular embodiment(s) disclosed. [Brief explanation of the drawings]

[0010] These and other features, aspects, and advantages of the inventions disclosed herein are described below with reference to drawings of certain specific embodiments, which are intended to be illustrative and not limiting of the invention.

[0011] [Figure 1] FIG. 1 is a cross-sectional view of a reactor according to at least one embodiment of the present invention.

[0012] [Figure 2] FIG. 2 is a cross-sectional view of another reactor in accordance with at least one embodiment of the present invention.

[0013] It will be appreciated that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] Although certain specific embodiments and examples are disclosed below, it will be understood by those skilled in the art that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention, and obvious modifications and equivalents thereof. It is therefore not intended that the scope of the disclosed invention should be limited by the specific disclosed embodiments described below.

[0015] As described in more detail below, exemplary embodiments of the present disclosure are directed to reactors in which films on substrates are etched, systems including such reactors, and methods of forming and using the reactors and systems. By way of example, embodiments of the present disclosure may relate to methods of etching via an atomic layer etching (ALE) process. Examples of films that can be etched using the systems and methods described herein include transition metal nitrides, transition metal oxides, and transition metal carbides. Gas types used to etch these films include mixed halide chemistries, particularly those with fluorine, chlorine, and / or bromine chemistries.

[0016] These mixed halide chemistries typically also etch the materials that form the reactor walls and components. With conventional reactors, such as nickel reaction chambers, significant contamination on the substrate surface can occur when a combination gas chemistry of fluorine and chlorine is used to process substrates in the reaction chamber. In this case, the gases can react with the nickel reaction chamber to form nickel halides that can contaminate the substrate surface.

[0017] 1 illustrates a reactor 100 in accordance with at least one embodiment of the present invention. The (e.g., etch) reactor 100 may include a reaction chamber 110, a susceptor 120, and a showerhead 130 or other suitable gas distribution structure. The showerhead / gas distribution structure 130 may distribute gas precursors coming from a remote plasma unit 140. The susceptor 120 holds a substrate 150 to be processed.

[0018] The reactor 100 may also include a first gas supply 160 and a second gas supply 170. The first gas supply 160 and the second gas supply 170 are illustrated as supplying gas to the remote plasma unit 140, but may additionally or alternatively provide gas(es) directly to the reaction chamber 110 without passing the gas(es) through the remote plasma unit 140. The first gas supply 160 and / or the second gas supply 170 may provide a metal halide gas, such as a transition metal or aluminum halide gas (e.g., TiCl, TiF, TiCl ... x , TiF x , MoCl x , MoF x , WCl x , W.F. x , NbCl x , NbF x , TaCl x , TaF x , VCl x , V.F. x , AlCl x , HfCl x , and / or ZrCl xThe first gas source 160 and / or the second gas source 170 may provide a precursor gas, including one or more of fluorine, chlorine, or bromine. The first gas source 160 and / or the second gas source 170 may provide a halide gas, including organic halides such as SbF5, CCl4, and / or metal oxyhalides such as WOCl4, and non-metal halides such as WOF4. As described in more detail below, precursors from the first gas source 160 and / or the second gas source 170 can react with the reaction chamber 110 material(s) and / or material(s) deposited onto portions of the reaction chamber 110 to produce gas compounds that can be relatively easily removed (e.g., purged from the reaction chamber 110). As used herein, "precursor" or "gas precursor" refers to a compound that participates in a chemical reaction to produce another compound. Precursors can include gases from gas sources (e.g., gas sources 160, 170) and / or other chemicals, such as chemical species generated when gases are exposed to a plasma, which may be directly from a reaction chamber, such as reaction chamber 110, or may be remote. Characteristics of the precursor(s) (e.g., metal halide gas(es)) and gas compounds may promote or facilitate high saturated vapor pressure and relatively little or no condensation to allow for efficient purging, as well as keeping contaminants in the reaction chamber low. The first and / or second gas sources 160, 170 may provide precursor(s) containing at least one halide atom, such as chlorine, fluorine, or bromine, from, for example, NbF or CCl. While illustrated with two gas sources, reactor 100 can include any suitable number of gas sources, including purge, carrier, and / or other reactant gas sources.

[0019] In some embodiments, the reaction chamber may be maintained at a reaction or process temperature of less than 1000°C and greater than about 20°C, greater than about 100°C, greater than about 200°C, greater than about 300°C, greater than about 400°C, greater than about 450°C, or between about 20°C and about 700°C, between about 100°C and about 700°C, between about 200°C and about 500°C, or between about 250°C and about 450°C. Suitable reactive gases and process conditions can be found in U.S. Patent Application Serial No. 15 / 835,262, filed December 7, 2017, entitled "THERMAL ATOMIC LAYER ETCHING PROCESSES," and PCT Application No. PCT / US2017 / 065170, filed December 7, 2017, entitled "THERMAL ATOMIC LAYER ETCHING PROCESSES," the contents of both of which are incorporated herein by reference to the extent not inconsistent with the present disclosure.

[0020] Components of the reactor 100 may be made of materials that react (e.g., volatilize) with precursors derived from gases (e.g., metal halide gases) from the first gas source 160 and / or the second gas source 170 to form gas compounds. In particular, the reaction chamber 110, the susceptor 120, and / or the showerhead 130 can be made of materials that will react with metal halide gases to form gas compounds. Materials include at least one of tungsten, molybdenum, titanium, niobium, tantalum, vanadium, aluminum, hafnium, zirconium, zinc, and mixtures and alloys thereof, such as vanadium alloys, zinc alloys, quartz, borosilicate quartz, or stainless steel. Other components of the reactor 100 that can be made of the materials listed above include gas lines, gas distribution blocks, heater plates, and gaskets, each of which is a potential source of contamination.

[0021] FIG. 2 illustrates another reactor 200 in accordance with at least one embodiment of the present disclosure. The reactor 200 may include a reaction chamber 210, a reaction chamber lining 220, a susceptor 230, and a gas distribution structure (e.g., a showerhead 240). The reaction chamber lining 220 may be a coating containing a material deposited onto the reaction chamber 210. Additionally or alternatively, reactor 200 components downstream and / or upstream from the reaction chamber, such as gas lines and pump lines, may be similarly coated. While illustrated as a vertical flow reactor with a showerhead 240, similar to the reactor 100, the reactor 200 may alternatively include a cross-flow reaction chamber instead of a showerhead type of reaction chamber. The showerhead 240 may distribute gas precursors coming from a remote plasma unit 260 and / or a first or second gas source, as described below. The susceptor 230 holds a substrate 250 to be processed.

[0022] The reactor 200 may also include a first gas supply 270 and a second gas supply 280. The first gas supply 270 and the second gas supply 280 are illustrated as supplying gas to the remote plasma unit 260, but may additionally or alternatively provide gas directly to the reaction chamber 210 without passing through the remote plasma unit 260. The first gas supply 270 and / or the second gas supply 280 may supply a transition metal or aluminum halide (such as fluorine, chlorine, or bromine) (e.g., TiCl, TiF, TiCl ... x , TiF x , MoCl x , MoF x , WCl x , W.F. x , NbCl x , NbF x , TaCl x , TaF x , VCl x , V.F. x , AlCl x , HfCl x , or ZrCl xThe first gas source 270 and / or the second gas source 280 may provide a metal halide gas, such as NbF or CCl, including one or more of the following: a non-metal halide gas such as SbF, an organic halide gas such as CCl, or a metal oxyhalide gas such as WOF. The precursors from the first gas source 270 and / or the second gas source 280 may react with the chamber lining 220 to form gas compounds with high saturated vapor pressures and little or no condensation to enable efficient purging, as well as to keep contaminants low in the reaction chamber 210. The first gas source 270 and the second gas source 280 may provide a precursor containing at least one halide atom, such as chlorine, fluorine, and / or bromine, such as NbF or CCl.

[0023] Components of the reactor 200, including the lining 220, may be made of materials that react with precursors from one or more gas sources 270, 280 (e.g., one or more metal halide gases) to form (e.g., volatile) gaseous compounds. In particular, the reaction chamber lining 220, the susceptor 230, and / or the showerhead 240 can be made of materials that react with the first precursor and / or the second precursor to form gaseous compounds. Materials can include, for example, at least one of tungsten, molybdenum, titanium, niobium, tantalum, vanadium, aluminum, hafnium, zirconium, zinc, vanadium alloys, zinc alloys, quartz, borosilicate quartz, and stainless steel. Other components of the reactor 200 that can be made and / or coated with the materials listed above include gas lines, gas distribution blocks, heater plates, and gaskets, as each of these is a potential source of contamination. According to some embodiments, components fabricated and / or coated with a material reactive with the first precursor and / or second precursor include surfaces of components located below or downstream of the showerhead plate to the pump line. According to exemplary embodiments, components fabricated and / or coated with a material reactive with the first precursor and / or second precursor include surfaces of components located downstream of the point where gas enters the space above the showerhead plate to the pump line. In some embodiments, components fabricated and / or coated with a material reactive with the first precursor and / or second precursor include surfaces of components located downstream of the point of the last valve before the reaction chamber to the pump line. In some embodiments, components fabricated and / or coated with a material reactive with the first precursor and / or second precursor include surfaces of components located downstream of the point of the penultimate valve before the reaction chamber to the pump line. In some embodiments, components made of and / or coated with a material that reacts with the first precursor and / or the second precursor comprise surfaces of the components located in a region having a temperature difference between the reaction chamber temperature and the edge of the reaction region of less than about 400°C, less than about 300°C, less than about 200°C, less than about 150°C, less than about 100°C, less than about 50°C, or less than about 25°C.A point in a pump line can be considered to be a point downstream from the reaction chamber or substrate from which chemicals, reaction by-products, particles, or other materials can no longer adversely affect the product or substrate in the reaction chamber, or the life of the reaction chamber, or have any other adverse effect on the process, product, substrate, or operation of the reactor.

[0024] The reaction chamber lining 220 may be formed on the surfaces within the reaction chamber 210 using a variety of methods, including, for example, liquid coating / deposition methods such as atomic layer deposition (ALD) and / or chemical vapor deposition (CVD) and / or electrodeposition. The reaction chamber lining 220 can have a thickness in the range of 0.1 mm to 10 mm, 0.5 to 5 mm, 1 to 3 mm, 0.0001 to 0.001 mm, 0.001 to 0.01 mm, or 0.01 to 0.1 mm, or in some cases less than 10 mm, but greater than about 10 nm, greater than about 100 nm, greater than about 1 μm, greater than about 10 μm, or greater than about 100 μm. With these thicknesses, the etch rate can be significantly lower (on the order of 1-10 nm / min or even lower), allowing for extremely long chamber lifetimes, resulting in lifetimes ranging from 1-5 years, or greater than about 1 week, greater than about 1 month, greater than about 6 months, greater than about 1 year, greater than about 2 years, greater than about 3 years, greater than about 4 years, or greater than about 5 years. In some embodiments, the etch rate of the reaction chamber material or lining is about 0.1 to about 100 nm / min, about 0.5 to about 50 nm / min, about 1 to about 50 nm / min, or greater than 0.1 nm / min, but less than about 5 nm / min, less than about 10 nm / min, less than about 25 nm / min, less than about 50 nm / min, or less than about 100 nm / min. In some embodiments, the etch rate of the reaction chamber material or lining is about 0.001 to about 10 nm, about 0.01 to about 5 nm, about 0.02 to about 2 nm, about 0.02 to about 1 nm per pulse or cycle of etching chemistry, or greater than 0.001 nm / min per pulse or cycle of etching chemistry, but less than about 10 nm, less than about 5 nm, less than about 1 nm, less than about 0.5 nm, or less than about 0.1 nm per pulse or cycle of etching chemistry.

[0025] Applying or utilizing a reaction chamber material and / or lining / coating that is etched by one or more reactive gases (e.g., precursors derived from one or more gases from gas sources such as gas sources 160, 170, 270, 280), or combinations of reactive gases, can effectively reduce impurity or contaminant levels in the etched substrate. In some embodiments, when the reaction chamber material or lining / coating is etched by one or more reactive gases or combinations of reactive gases, the substrate has less than about 5 at.%, less than about 1 at.%, less than about 0.5 at.%, less than about 0.1 at.%, less than about 0.05 at.%, less than about 0.01 at.%, less than about 0.005 at.%, or less than about 0.001 at.% of impurities from the reaction chamber, e.g., as metal contamination. In some cases, when the reaction chamber material or lining / coating is etched with one or more reactive gases or combinations of reactive gases, the substrate has less than 10,000 ppm, less than 1,000 ppm, less than 100 ppm, less than 50 ppm, or less than 10 ppm, or in some cases an undetectable amount of impurities from the reaction chamber, e.g., as metal contamination.

[0026] The specific implementations shown and described are illustrative of the invention and its best mode and are not intended to otherwise limit the scope of aspects and implementations in any way. Indeed, for the sake of brevity, conventional manufacturing, association, preparation, and other functional aspects of systems, reactors, or methods may not be described in detail. Furthermore, connecting lines shown in the various figures are intended to represent example functional relationships and / or physical couplings between the various elements. Many alternative or additional functional relationships or physical connections may be present in an actual system and / or may not be present in some embodiments.

[0027] It should be understood that the configurations and / or approaches described herein are exemplary in nature, and that these specific embodiments or examples are not to be construed in a limiting sense, as numerous variations are possible. The particular routines or methods described herein may represent one or more of any number of processing strategies. As such, various illustrated operations may be performed in the illustrated sequence, in other sequences, or in some cases omitted.

[0028] The subject matter of the present disclosure includes all novel and non-obvious combinations and subcombinations of the various processes, systems, reactors, and configurations, as well as other features, functions, operations, and / or properties disclosed herein, and any and all equivalents thereof.

Claims

1. 1. A semiconductor processing system comprising: a reaction chamber containing a first material; a susceptor comprising a second material and configured to hold a substrate for processing; a showerhead including a third material; a first gas supply configured to provide a first gas precursor to the reaction chamber through a first gas line between the first gas supply and the reaction chamber in a process of etching a film on the substrate, the first gas line being made of the first material, the second material, or the third material; a second gas supply source configured to provide a second gas precursor to the reaction chamber through a second gas line between the second gas supply source and the reaction chamber in the process of etching a film on the substrate, the second gas line being made from the first material, the second material, or the third material; the first material, the second material, and the third material are configured to react with one or more of the first gas precursor and the second gas precursor to form volatile gas compounds; The semiconductor processing system is configured such that the volatile gas compounds are removed from the semiconductor processing system.

2. The semiconductor processing system of claim 1 further comprising a reaction chamber lining.

3. 3. The semiconductor processing system of claim 2, wherein said reaction chamber lining comprises a coating comprising a material to be deposited in said reaction chamber.

4. 4. The semiconductor processing system of claim 3, wherein the reaction chamber lining has a thickness of 0.0001 to 0.001 mm.

5. 3. The semiconductor processing system of claim 2, wherein said reaction chamber lining is made of a material selected from the group consisting of tungsten, molybdenum, titanium, niobium, tantalum, vanadium, aluminum, hafnium, zirconium, zinc, vanadium alloys, zinc alloys, quartz, borosilicate quartz, and stainless steel.

6. 3. The semiconductor processing system of claim 2, wherein said reaction chamber lining is made of said first material, said first material comprising at least one of tungsten, molybdenum, aluminum, zinc, and a zinc alloy.

7. The first gas precursor is TiCl ４ , TiF ４ , TiCl ｘ , TiF ｘ , MoCl ｘ , MoF ｘ , WCl ｘ , W.F. ｘ , NbCl ｘ , NbF ｘ , TaCl ｘ , TaF ｘ , VCl ｘ , V.F. ｘ , AlCl ｘ , HfCl ｘ , or ZrCl ｘ 10. The semiconductor processing system of claim 1, comprising or derived from one or more of:

8. The semiconductor processing system of claim 1 , wherein the second gas precursor comprises a halide.

9. At least one of the first gas precursor and the second gas precursor is NbF ５ , CCl ４ or WOF ４ 9. The semiconductor processing system of claim 8, comprising:

10. 10. The semiconductor processing system of claim 1, wherein said susceptor is made from said second material, said second material comprising at least one of tungsten, molybdenum, zinc, and a zinc alloy.

11. The semiconductor processing system of claim 1, wherein the third material comprises at least one of tungsten, molybdenum, zinc, and a zinc alloy.

12. 10. The semiconductor processing system of claim 1, wherein at least one of said first gas source and said second gas source comprises at least one of a non-metal halide, an organic halide, and a metal oxyhalide.

13. 10. The semiconductor processing system of claim 1, further comprising a remote plasma unit, wherein at least one of the first gas precursor and the second gas precursor is flowed through the remote plasma unit before entering the showerhead.

14. 14. The semiconductor processing system of claim 13, wherein both the first gas precursor and the second gas precursor are flowed through the remote plasma unit before entering the showerhead.

15. 14. The semiconductor processing system of claim 13, wherein at least one of the first gas precursor and the second gas precursor is additionally supplied to the reaction chamber without passing through the remote plasma unit.

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