Silicon nitride and silicon oxide deposition methods using fluorine inhibitors

Abstract

A method of depositing material on a surface of a substrate is disclosed. The method includes using a fluorine reactant to reduce a per-cycle growth rate of silicon oxide and / or silicon nitride deposited on the surface of the substrate.

Description

Technical Field

[0001] This disclosure generally relates to methods for depositing materials onto a substrate surface, structures formed using such methods, and systems for depositing materials. Background Technology

[0002] In the fabrication of electronic devices, such as semiconductor devices, it may be desirable to fill gaps (e.g., spaces between trenches, vias, or features) on the substrate surface with insulating materials such as silicon nitride or silicon oxide. Atomic layer deposition (ALD) can be used to conformally deposit silicon nitride or silicon oxide over these gaps, thereby filling them.

[0003] In some cases, plasma-enhanced processes such as plasma-enhanced ALD (PEALD) can be used to deposit silicon nitride or silicon oxide. Compared to methods without plasma, plasma-enhanced processes can operate at relatively lower temperatures and / or exhibit relatively higher deposition rates.

[0004] Unfortunately, silicon nitride and silicon oxide deposited using PEALD on high aspect ratio features (e.g., gaps with an aspect ratio of 3 or greater) tend to form voids in the deposited material because less material is deposited at the bottom of the feature (e.g., on the bottom or side surfaces near the bottom of the gap—compared to the gap side surfaces at or near the top of the gap). Poor conformability and / or undesirable deposition profiles can be attributed to the loss of active material (e.g., free radicals), which can occur through surface recombination of free radicals, for example, at the gap sidewalls.

[0005] Efforts to improve the low conformality and / or gap-filling capability of PEALD-deposited materials have focused on adjusting process parameters, such as RF power, plasma exposure time, and pressure, to provide sufficient activating material, such as radicals, near the feature bottom, thereby increasing the amount of material deposited thereon. However, because radical recombination is an intrinsic phenomenon, this effort is limited. Furthermore, recent device fabrication specifications typically require low plasma levels near the feature bottom. For such applications, conventional methods involving increasing the amount of active material and / or the energy of that active material cannot be used.

[0006] To overcome these problems, various techniques have been proposed. For example, U.S. Patent No. 9,887,082 to Pore et al. discloses a method for filling gaps. This method includes providing a precursor into a reaction chamber to form an adsorbed material on a substrate surface, exposing the adsorbed material to a nitrogen plasma to form a material on top of a nitrogen-containing feature, and providing a reactant plasma into the reaction chamber, wherein nitrogen acts as a reactant inhibitor, resulting in less material deposited on top of the gap compared to conventional PEALD techniques. This technique can produce silicon nitride with fewer voids or seams than conventional techniques; however, voids and seams can still form within the silicon nitride, especially in gaps with higher aspect ratios. Furthermore, for some applications, the wet etching rate of silicon nitride deposited using this technique may be undesirably high.

[0007] Therefore, there is a need for improved methods for depositing materials suitable for filling gaps on a substrate surface, and for structures formed using such methods. Any discussion of problems and solutions involved in related art has been included in this disclosure merely to provide context for the invention and should not be construed as an admission that any or all of the discussions were known at the time of making this invention. Summary of the Invention

[0008] Various embodiments of this disclosure relate to methods for depositing material onto a substrate surface—for example, depositing material onto a feature on the substrate surface—suitable for filling gaps on the substrate surface. While the ways in which various embodiments of this disclosure address the disadvantages of existing methods and systems will be discussed in more detail below, in general, various embodiments of this disclosure provide improved methods suitable for filling gaps on surfaces while mitigating the formation of voids or seams that may occur when using conventional techniques.

[0009] According to embodiments of this disclosure, a method is provided for depositing one or more of silicon nitride and silicon oxide onto a substrate surface. The method may include: providing a fluorine reactant to a reaction chamber for a fluorine reactant pulse; providing a silicon precursor to a reaction chamber for a silicon precursor pulse; providing one or more of a nitrogen reactant and an oxygen reactant to a reaction chamber for a reactant pulse; and optionally providing a hydrogen reactant to a reaction chamber for a hydrogen reactant pulse. When hydrogen is provided, hydrogen may be introduced into the reaction chamber alone, or it may be mixed with another reactant, such as a nitrogen reactant, and introduced into the reaction chamber simultaneously with the nitrogen reactant. Examples of these embodiments include, according to these embodiments, the silicon precursor may include one or more of silanes, halosilanes, and organosilanes. The nitrogen reactant may include one or more of nitrogen (N2), N2O, and NO, and / or the oxygen reactant may include, for example, O2. The fluorine reactant may include one or more of NF3, CF4, C2F6, SF6, NH2F, C3F8, and F2. The hydrogen reactant may include one or more of hydrogen (H2), NH3, N2H4, and N2H2. As described in more detail below, various combinations of reactants can be continuously supplied to the reaction chamber during two or more process steps. Alternatively or concurrently, in some cases, two or more process steps may overlap in time and space. In some cases, the order of two or more steps can be specified. In some cases, two or more steps may be specified not to overlap. In such cases, overlap may mean that reactants enter or are in the same reaction chamber simultaneously (e.g., without intermediate purging). According to a further example of this disclosure, one or more reactants can be exposed to plasma to form an activating material. The plasma can be a direct or remote plasma. The methods described herein can be used to form silicon oxide and / or silicon nitride suitable for filling gaps on surfaces, suitable for forming hard masks, etc.

[0010] According to yet another exemplary embodiment of this disclosure, a deposition apparatus configured to perform the methods described herein is provided.

[0011] According to yet another exemplary embodiment of this disclosure, the structure includes silicon oxide and / or silicon nitride deposited according to the methods described herein.

[0012] Referring to the accompanying drawings, these and other embodiments will become apparent to those skilled in the art from the following detailed description of certain embodiments; the invention is not limited to any particular embodiment disclosed. Attached Figure Description

[0013] A more complete understanding of exemplary embodiments of the present disclosure can be obtained by considering the following illustrative drawings, along with reference to the detailed description and claims.

[0014] Figure 1 A method according to at least one embodiment of the present disclosure is shown.

[0015] Figure 2-5 The timing of the method according to an embodiment of this disclosure is shown.

[0016] Figure 6 A method according to at least one embodiment of the present disclosure is shown.

[0017] Figure 7 and 8 The timing of the method according to an embodiment of this disclosure is shown.

[0018] Figure 9 The structure of a layer including gaps and partially filled gaps is shown, wherein the layer is relatively thin near the bottom of the gap.

[0019] Figure 10 The structure of a layer including gaps and partially filling gaps according to an embodiment of the present disclosure is shown, wherein the layer is relatively thick near the bottom of the gap.

[0020] Figure 11 The structure during a gap-filling method according to at least one embodiment of the present disclosure is shown.

[0021] Figure 12 A system according to at least one embodiment of the present disclosure is shown.

[0022] It should be understood that the elements in the accompanying drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some elements may be exaggerated relative to other elements to aid in understanding the illustrated embodiments of this disclosure. Detailed Implementation

[0023] Although certain embodiments and examples are disclosed below, those skilled in the art will understand that the invention extends beyond the specific disclosed embodiments and / or uses of the invention, as well as obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited to the specific disclosed embodiments described below.

[0024] This disclosure generally relates to methods for depositing materials onto a substrate surface, deposition apparatus for performing the methods, and structures formed using the methods. The methods and systems described herein can be used to process substrates to form, for example, electronic devices. For instance, the systems and methods described herein can be used to deposit silicon nitride and / or silicon oxide onto a substrate surface, the substrate including high aspect ratio features to, for example, fill gaps within or between the high aspect ratio features.

[0025] In this disclosure, "gas" can include materials that are gaseous at ambient temperature and pressure, evaporated solids, and / or evaporated liquids, and can consist of a single gas or a mixture of gases, depending on the circumstances. Gases other than process gases, i.e., gases introduced without passing through gas distribution components (such as spray heads, other gas distribution devices, etc.), can be used, for example, to seal the reaction space, including sealing gases, such as rare gases. In some embodiments, the term "precursor" generally refers to a compound that participates in a chemical reaction to produce another compound, particularly a compound constituting the membrane matrix or membrane backbone, while the term "reactant" refers to a compound other than the precursor that activates, modifies, or catalyzes the reaction of the precursor, wherein, when RF power is applied, the reactant can provide elements (such as O, N, C) to the membrane matrix and become part of the membrane matrix. The term "inert gas" refers to a gas that does not participate in a chemical reaction and / or excites the precursor when RF power is applied, but unlike reactants, it may not become part of the membrane matrix to a perceptible degree.

[0026] As used herein, the term "substrate" can refer to any one or more underlying materials that can be used to form or on which devices, circuits, or films can be formed. Substrates can include bulk materials such as silicon (e.g., single-crystal silicon), other Group 4 materials such as germanium, or compound semiconductor materials such as Group 3-5 or Group 2-6 semiconductors, and can include one or more layers on or under the bulk material. Furthermore, substrates can include various topologies, such as recesses, lines, etc., formed within or on at least a portion of the substrate layers.

[0027] In some embodiments, a “membrane” refers to a layer that extends continuously in a direction substantially perpendicular to the thickness direction, without pinholes to cover the entire target or associated surface, or simply a layer that covers the target or associated surface. In some embodiments, a “layer” refers to a structure of a certain thickness formed on a surface, or a synonym for a membrane or non-membrane structure. A membrane or layer may consist of discrete single membranes or layers or multiple membranes or layers having certain properties, and the boundaries between adjacent membranes or layers may or may not be clear, and may or may not be established based on the physical, chemical and / or any other properties, formation process or sequence and / or function or purpose of adjacent membranes or layers.

[0028] The term “cyclic deposition process” or “cyclic deposition process” can refer to the sequential introduction of precursors (and / or reactants) into a reaction chamber to deposit a layer on a substrate, and includes processing techniques such as atomic layer deposition (ALD), cyclic chemical vapor deposition (cyclic CVD), and hybrid cyclic deposition processes that include ALD components and cyclic CVD components.

[0029] As used herein, the term "atomic layer deposition" (ALD) can refer to a vapor-phase deposition process in which deposition cycles, preferably multiple consecutive cycles, are performed in a processing chamber. Typically, during each cycle, a precursor is introduced and can be chemisorbed onto the deposition surface (e.g., a substrate surface or an underlying surface previously deposited, such as material from a previous ALD cycle), forming a monolayer or sub-monolayer that is not readily reactive with further precursors (i.e., a self-limiting reaction). Subsequently, a reactant (e.g., another precursor or reactive gas) can be introduced into the processing chamber to convert the chemisorbed precursor into the desired material on the deposition surface. Typically, this reactant is capable of further reacting with the precursor. Furthermore, following the conversion of the chemisorbed precursor, a purging step can be used during each cycle to remove excess precursor and / or excess reactant and / or reaction byproducts from the processing chamber. Furthermore, the term "atomic layer deposition" as used herein also includes processes specified by related terms such as chemical vapor deposition, atomic layer epitaxy (ALE), molecular beam epitaxy (MBE), gas-source MBE or organometallic MBE, and chemical beam epitaxy when performed with alternating pulses of precursor components, reactant gases, and purge gases (e.g., inert carrier gases). PEALD refers to the ALD process in which plasma is applied in one or more ALD steps.

[0030] As used herein, silicon nitride refers to a material comprising silicon and nitrogen. Silicon nitride can be represented by the formula SixNy (e.g., Si3N4). In some cases, silicon nitride may not include stoichiometric amounts of silicon nitride. In some cases, silicon nitride may include other elements such as carbon, oxygen, and hydrogen.

[0031] As used herein, silicon oxide refers to a material comprising both silicon and oxygen. Silicon oxide can be represented by the chemical formula SiOx (e.g., SiO2). In some cases, silicon oxide may not include stoichiometric amounts of silicon oxide. In other cases, silicon oxide may include other elements such as carbon, nitrogen, and hydrogen.

[0032] As used herein, silicon oxynitride refers to a material comprising silicon, oxygen, and nitrogen. Silicon oxynitride can be represented by the chemical formula SiOxNy. In some cases, silicon oxynitride may include other elements, such as carbon and hydrogen. Silicon oxynitride can include silicon oxide and silicon nitride.

[0033] Furthermore, in this disclosure, any two numbers of a variable can constitute a working range for the variable, as the working range can be determined based on routine work, and any indicated range can include or exclude endpoints. Additionally, any value of the indicated variable (whether or not it is indicated by “about”) can refer to an exact value or an approximate value and includes equivalents, and in some embodiments can refer to the average, median, representative value, multi-value, etc. Furthermore, in this disclosure, in some embodiments, the terms “comprising,” “consisting of,” and “having” can independently mean “generally or broadly comprising,” “including,” “substantially constituted of,” or “consisting of.” In this disclosure, in some embodiments, the meaning of any definition does not necessarily exclude the common and customary meaning.

[0034] In this disclosure, "continuously" can mean one or more of the following: without breaking the vacuum, without interrupting the timeline, without performing any material intervention steps, without changing the processing conditions, immediately following as the next step, or in some embodiments without intervening discrete physical or chemical structures between two structures other than the two structures.

[0035] Now turn to the attached image. Figure 1 A method 100 according to at least one embodiment of the present disclosure is illustrated, the method being adapted to deposit one or more of silicon nitride and silicon oxide onto a substrate surface in a reaction chamber. Method 100 includes the steps of: providing a substrate in the reaction chamber (step 102); providing a fluorine reactant to the reaction chamber for a fluorine reactant pulse (step 104); providing a silicon precursor to the reaction chamber for a silicon precursor pulse (step 106); and providing one or more of a nitrogen reactant and an oxygen reactant to the reaction chamber for a reactant pulse (step 108). As shown, method 100 may further include providing a hydrogen reactant to the reaction chamber for a hydrogen reactant pulse (step 110). Method 100 may include a cyclic (e.g., ALD) process, such as a PEALD process.

[0036] Step 102 includes providing at least one substrate into a reaction chamber and bringing the substrate to a desired temperature. The reaction chamber may include a PEALD reaction chamber. During step 102, the temperature within the reaction chamber may reach a temperature suitable for subsequent processing, for example, between about -10°C and about 1000°C, or between about 75°C and about 600°C. Similarly, the pressure within the reaction chamber may be controlled to provide a reduced pressure atmosphere for subsequent processing. For example, the pressure within the reaction chamber may be less than 5000 Pa, or less than 2000 Pa, or less than 1000 Pa, or between about 0.0001 Pa and about 101325 Pa, or between about 10 Pa and about 13333 Pa.

[0037] During step 104, the surface of the substrate is exposed to the fluorine reactant. During this step, the temperature and / or pressure may be as described above in conjunction with step 102. According to an example of this disclosure, plasma is applied during at least a portion of step 104, which involves supplying the fluorine reactant to the reaction chamber. The plasma may be a remote plasma, thereby introducing the activated fluorine material into the reaction chamber, or a direct plasma, wherein the activated fluorine material is formed within the reaction chamber. According to an example of this disclosure, the activated fluorine material may preferentially react with the top surface of the feature (e.g., a gap), such that the effect of the fluorine reacting with the substrate surface is greater near the top of the feature than at the bottom. The presence of fluorine on the surface increases the cultivation of subsequently deposited silicon nitride and / or silicon oxide and / or decreases the growth rate per cycle.

[0038] The power used to generate the activated fluorine substance during step 104 can be between 0 W and about 10,000 W, or between about 50 W and about 3,000 W. The frequency of the power can be between about 430 kHz and about 13.56 MHz.

[0039] According to examples of this disclosure, the temperature inside the reaction chamber can be relatively low, for example below 25°C or below 550°C, to prevent or mitigate material etching during step 104.

[0040] The fluorine reactant provided during step 104 may include any suitable fluorine-containing reactant. For example, the fluorine reactant may be or include one or more of NF3, CF4, C2F6, SF6, NH2F, C3F8, and F2. In some cases, the fluorine reactant may be provided to the reaction chamber and / or a remote plasma unit mixed with a carrier gas, such as an inert gas. Suitable inert or carrier gases include, for example, N2, Ar, He, Ne, and Xe.

[0041] The exemplary fluorine reactant flow rate during step 104 can be from about 1 sccm to about 1000 sccm or from about 2 sccm to about 100 sccm. During step 104, the pulse duration of the fluorine reactant stream can be from about 0.01 seconds to about 600 seconds or from about 1 second to about 300 seconds.

[0042] According to examples of this disclosure, the process conditions of step 104 can be controlled to mitigate the etching of the underlying material and / or control the areas affected by the fluorine reactant. For example, process conditions can be selected such that the growth rate of the subsequently formed material in the top region of the feature (e.g., the top 25% or the top 10%) is lower than that of the remainder of the feature. Furthermore, when a hydrogen reactant is used, it can promote the growth of the lower / remaining portion of the feature.

[0043] During step 106, a silicon precursor is supplied to the reaction chamber for silicon precursor pulsation. The pressure and temperature within the reaction chamber can be as described above in conjunction with step 102. In some cases, the substrate, gas distribution system (e.g., spray nozzle), and / or reaction chamber wall temperature during step 106 can be higher than the substrate, gas distribution system, and / or reaction chamber wall temperature during step 104, for example, to facilitate deposition during steps 106 and 108 and 110. According to an example of this disclosure, no plasma is supplied during step 106.

[0044] The silicon precursor provided in step 106 may include one or more of silanes, halosilanes, and organosilanes. Exemplary halosilanes include one or more of dichlorosilane, diiodosilane, hexachlorodisilane, octachlorotrisilane, dibromosilane, tribromosilane, trichlorosilane (HSiCl3), chlorosilane (H3SiCl), silicon tetrachloride (SiCl4), bromosilane (H3SiBr), triiodosilane (HSil3), iodosilane (H3SiI), diiodosilane (H2Si2I4), H4Si2I2, and H5Si2I. Exemplary organosilanes include one or more of aminosilanes and heterosilanes. As a specific example, the silicon precursor may include one or more of the following: tris(dimethylamino)silane, bis(tert-butylamino)silane, bis(sec-butylamino)silane, trisilaneamine, neopentyl silane, bis(dimethylamino)silane (DMAS), bis(diethylamino)silane (BDEAS), bis(ethylmethylamino)silane (BEMAS), tetra(dimethylamino)silane (TKDMAS), trimethylsilane (SiH(CH3)3), tetramethylsilane (Si(Ch3)4), silane, tetra(ethoxy)silane (TEOS, Si(OC2H5)4), tris(tert-butoxy)silanol (TBOS), tris(tert-pentoxy)silanol (TPSOL), and dimethyldichlorosilane (Si(OC2H5)4, Si(CH3)2(OCH3)2).

[0045] The exemplary silicon precursor flow rate during step 106 may be from about 1 sccm to about 500 sccm or from about 3 sccm to about 100 sccm. During step 106, the pulse duration of the silicon precursor flow may be from about 0.1 seconds to about 10 seconds or from about 0.2 seconds to about 3 seconds.

[0046] During step 108, one or more of the nitrogen reactant and the oxygen reactant are supplied to the reaction chamber for reactant pulses. The temperature and pressure inside the reaction chamber during step 108 may be the same as or similar to the temperature and pressure inside the reaction chamber during steps 104 or 106.

[0047] According to an example of this disclosure, plasma is applied during at least a portion of step 108, which involves supplying one or more of nitrogen and oxygen reactants to the reaction chamber. The plasma can be a remote plasma or a direct plasma. The power of the plasma generated during step 108 can be between 0 W and about 10,000 W, or between about 50 W and about 3,000 W. The frequency of the power can be between about 400 kHz and about 60 MHz, or about 13.56 MHz.

[0048] Nitrogen reactants may include one or more nitrogen-containing compounds, such as nitrogen (N2), N2O, and NO. Alternatively, oxygen reactants may include oxygen-containing compounds, such as O2.

[0049] The exemplary nitrogen reactant flow rate during step 108 can be from about 100 sccm to about 50,000 sccm or from about 5,000 sccm to about 30,000 sccm. During step 108, the pulse duration of the nitrogen reactant stream can be from about 0.05 seconds to about 20 seconds or from about 0.1 seconds to about 10 seconds. During step 108, the exemplary oxygen reactant flow rate can be from about 100 sccm to about 50,000 sccm or from about 5,000 sccm to about 30,000 sccm. During step 108, the pulse duration of the oxygen reactant stream can be from about 0.05 seconds to about 20 seconds or from about 0.05 seconds to about 10 seconds.

[0050] During optional step 110, hydrogen reactants are supplied to the reaction chamber for hydrogen reactant pulses. The temperature and pressure inside the reaction chamber during step 110 may be the same as or similar to the temperature and pressure inside the reaction chamber during any of steps 104-108, and particularly any of steps 106, 108.

[0051] According to an example of this disclosure, plasma is applied during at least a portion of step 110. The plasma can be a remote plasma or a direct plasma. The power of the plasma generated during step 110 can be between 0 W and about 10,000 W, or between about 50 W and about 3,000 W. The frequency of the power can be between about 400 kHz and about 60 MHz, or about 13.56 MHz.

[0052] The hydrogen reactants may include one or more of, for example, hydrogen (H2), NH3, N2H4, and N2H2. An exemplary hydrogen reactant flow rate during step 108 may be from about 1 sccm to about 5000 sccm or from about 10 sccm to about 500 sccm. During step 108, the pulse duration of the hydrogen reactant stream may be from 0.1 seconds to about 15 seconds or from about 0.5 seconds to about 5 seconds.

[0053] As mentioned above, the use of activated hydrogen and fluorine substances can promote deposition in the lower part of the feature compared to the top. This is especially true for halogenated silanes and / or aminosilane silicon precursors.

[0054] Steps 106-110 can be considered as a deposition cycle, which can be repeated once or multiple times (loop 112). Method 100 may further include loop 114 repeating steps 104-110. For example, loop 114 can be repeated multiple times until the gaps on the substrate surface are filled with one or more of silicon nitride and silicon oxide and / or the desired film thickness is achieved. Furthermore, although not shown separately, any of steps 104-110 can be repeated before proceeding to the next step.

[0055] Two or more of steps 106-110 may be performed simultaneously or may at least partially overlap in time. For example, steps 106 and 110 may overlap or be performed simultaneously. Alternatively, steps 108 and 110 may overlap. Furthermore, as described in more detail below, one or more steps—such as providing one or more of nitrogen and oxygen reactants to the reaction chamber—may be performed continuously during the steps of providing the silicon precursor, optionally providing the hydrogen reactant, and / or providing the fluorine reactant.

[0056] Furthermore, unless otherwise stated, the steps of method 100 can be performed in any order. In the illustrated example, step 104 occurs before step 106. However, as shown below, the method may include a step of introducing the fluorine reactant after one or more deposition cycles. According to some examples, the steps of providing the hydrogen reactant (110) and providing the fluorine reactant (104) do not overlap in the reaction chamber.

[0057] Figure 2 Timing 200 for a method (e.g., method 100) for forming silicon nitride on a substrate surface is shown. Timing 200 includes a fluorine treatment cycle 202 and a deposition cycle 204.

[0058] The fluorine treatment cycle 202 may include providing purge gas, nitrogen reactants, and fluorine reactants during a first period 206 (e.g., without plasma) and a second period 208 (with plasma). The conditions for the fluorine treatment cycle 202 may be as described above in combination with steps 104 and 108.

[0059] Deposition cycle 204 may include providing silicon precursors and nitrogen reactants in time period 210. The reaction chamber may then be purged—for example, using purge gas and nitrogen reactants during time period 212. While the nitrogen reactants continue to flow, plasma-generating power may be applied in time period 214. The reaction chamber may then be purged in time period 216. Gas flow rates may be combined as described above. Figure 1 As stated above.

[0060] Timing 200 may include multiple repeated deposition cycles 204. Furthermore, timing 200 may include multiple repeated fluorine treatment cycles 202 and deposition cycles 204, as described above. Figure 1 As described above. In the illustrated example, no separate hydrogen reactant is provided during method 200.

[0061] Figure 3 The timing sequence 300 of a method (e.g., method 100) for forming silicon nitride on a substrate surface using hydrogen reactants is shown. The timing sequence 300 includes a fluorine treatment cycle 302 and a deposition cycle 304.

[0062] The fluorine treatment cycle 302 may include providing purge gas, providing nitrogen reactants, and providing fluorine reactants in a first period 306 (e.g., without plasma) and a second period 308 (with plasma), as described above in conjunction with fluorine treatment step 202.

[0063] Deposition cycle 304 may include providing silicon precursors and nitrogen reactants in time period 310. The reaction chamber may then be purged during time period 312—for example, using a purge gas, nitrogen reactants, and hydrogen reactants. While the nitrogen and hydrogen reactants continue to flow, plasma-generating power may be applied in time period 314 to produce nitrogen and hydrogen-activated material. The reaction chamber may then be purged in time period 316.

[0064] Timing 300 may include multiple repeated deposition cycles 304. Furthermore, timing 300 may include multiple repeated fluorine treatment cycles 302 and deposition cycles 304, as described above. Figure 1 The various gas flow rates during time period 306-316 can be combined with the above description. Figure 1 As stated above.

[0065] Figure 4 Timing 400 is shown for a method (such as method 100) for forming silicon oxide on a substrate surface without additional hydrogen reactants. Timing 400 is similar to timing 200 (except that timing 400 includes oxygen reactants instead of nitrogen reactants). Timing 400 includes a fluorine treatment cycle 402 and a deposition cycle 404.

[0066] The fluorine treatment cycle 402 may include providing purge gas, providing nitrogen reactants, and providing fluorine reactants in a first period 406 (e.g., without plasma) and a second period 408 (with plasma), as described above in conjunction with fluorine treatment step 202.

[0067] Deposition cycle 404 may include providing silicon precursors and oxygen reactants in time period 410. The reaction chamber may then be purged during time period 412—for example, using purge gas and oxygen reactants. While the oxygen reactants continue to flow, plasma-generating power may be applied in time period 414 to produce oxygen-activated material. The reaction chamber may then be purged in time period 416.

[0068] Timing 400 may include multiple repeated deposition cycles 404. Furthermore, timing 400 may include multiple repeated fluorine treatment cycles 402 and deposition cycles 404, as described above. Figure 1 As stated above.

[0069] Figure 5 Timing 500 is shown for a method (e.g., method 100) of forming silicon oxide on a substrate surface using hydrogen reactants. Timing 500 includes a fluorine treatment cycle 502 and a deposition cycle 504.

[0070] The fluorine treatment cycle 502 may include providing purge gas, oxygen reactants (e.g., with carrier gas), and fluorine reactants in a first period 506 (e.g., without plasma) and a second period 508 (with plasma), as described above in conjunction with fluorine treatment step 202.

[0071] Deposition cycle 504 may include providing silicon precursors and oxygen reactants in phase 510. The reaction chamber may then be purged during phase 512—for example, using a purge gas, oxygen reactants, and / or a carrier gas, along with hydrogen reactants. While the oxygen and hydrogen reactants continue to flow, plasma-generating power may be applied in phase 514 to produce oxygen- and hydrogen-activated material. The reaction chamber may then be purged in phase 516.

[0072] Timing 500 may include multiple repeated deposition cycles 504. Furthermore, timing 500 may include multiple repeated fluorine treatment cycles 502 and deposition cycles 504, as described above. Figure 1 As stated above.

[0073] Figure 6A method 600 according to at least one embodiment of the present disclosure is shown, adapted to deposit one or more of silicon nitride and silicon oxide onto a substrate surface in a reaction chamber. Method 600 includes the steps of: providing a substrate in the reaction chamber (step 602), providing a silicon precursor to the reaction chamber for a silicon precursor pulse (step 604), providing one or more of a nitrogen reactant and an oxygen reactant to the reaction chamber for a reactant pulse (step 606), and providing a fluorine reactant to the reaction chamber for a fluorine reactant pulse (step 610). As shown, method 600 may further include providing a hydrogen reactant to the reaction chamber for a hydrogen reactant pulse (step 608). Steps 604-610 may be the same as or similar to the corresponding steps in method 100; however, in method 600, step 610 is performed after a deposition cycle including steps 604-608, rather than before the deposition cycle.

[0074] Similar to method 100, method 600 may include repeating steps 604-608 (ring 612) and / or repeating steps 604-610 (ring 614).

[0075] Figure 7 Timing 700 is shown for a method (e.g., method 600) for forming one or more of silicon nitride and silicon oxide on a substrate surface. Timing 700 includes a deposition cycle 702 and a fluorine treatment cycle 704.

[0076] Deposition cycle 702 may include providing silicon precursors and reactants, as well as hydrogen reactants, in time period 706. The reaction chamber may then be purged during time period 708—for example, using a purge gas, reactants, and hydrogen reactants. While the reactants and hydrogen reactants continue to flow, plasma-generating power may be applied in time period 710 to produce reactants and hydrogen-activated reactant material. Optionally, the reaction chamber may then be purged during a reactant purging time period (not shown).

[0077] The fluorine treatment cycle 704 may include providing purge gas and reactants (e.g., excluding hydrogen reactants) and fluorine reactants during a first period 712 (e.g., without plasma) and a second period 714 (with plasma), as described above in conjunction with fluorine treatment step 202. The reaction chamber may then be purged during the fluorine reactant purging period 716.

[0078] Timing 700 may include multiple repeated deposition cycles 702. Furthermore, timing 700 may include multiple repeated deposition cycles 702 and fluorine treatment cycles 704, as described above. Figure 6 As stated above.

[0079] Figure 8Another timing sequence 800 is shown for a method (such as method 600) for forming one or more of silicon nitride and silicon oxide on a substrate surface. Timing sequence 800 includes a deposition cycle 802, a hydrogen cycle 804, and a fluorine treatment cycle 806.

[0080] In the illustrated example, deposition cycle 802 includes providing silicon precursors and reactants during phase 808. The reaction chamber can then be purged during phase 810—for example, using a purge gas and reactants. While the reactants continue to flow, plasma-generating power can be applied during phase 812 to produce reactant-activated material. The reaction chamber can then be purged during reactant purging phase 814.

[0081] Hydrogen cycle 804 includes supplying hydrogen reactants to the reaction chamber and providing power to the plasma unit during time period 816. The reactor conditions for step 804 can be as described above in conjunction with step 608.

[0082] The fluorine treatment cycle 806 may include providing purge gas and reactants (e.g., excluding hydrogen reactants) and fluorine reactants during period 818, during which plasma is applied for at least a portion of period 818. The plasma conditions may be combined as described above. Figure 1 and 6 The reaction chamber can then be purged during the fluorine reactant purging period (not shown separately).

[0083] Timing 800 may include multiple repeated deposition cycles 802—for example, prior to steps 804 and 806. Furthermore, timing 800 may include multiple repeated deposition cycles 802, a hydrogen cycle 816, and / or a fluorine treatment cycle 818, such as... Figure 8 As shown.

[0084] Figure 9 A structure 900 is shown, including gaps 902 and 904 formed on the surface of a substrate 906. Structure 900 includes a silicon nitride or silicon oxide layer 908 formed according to conventional methods for covering the substrate 906. As shown, the thickness t1 of the silicon nitride or silicon oxide layer 908 near the top of the gap 902 is greater than the thickness of the layer 908 at the bottom of the gap 902. When the gap 902 is filled using conventional techniques, voids are formed within the gap 902.

[0085] Figure 10 A structure 1000 is shown, including gaps 1002 and 1004 formed on the surface of a substrate 1006. Structure 1000 includes one or more of silicon nitride and silicon oxide 1008 formed according to methods described herein (e.g., method 100 or method 600). As shown, the thickness t1 of one or more of the silicon nitride and silicon oxide 1008 near the top of the gap 1002 is less than the thickness of the layer 1008 at the bottom of the gap 1002. Figure 11 As further shown, when gap 1002 is filled using the exemplary method disclosed herein, no voids are formed within gap 1002. The conformality of the deposited silicon nitride and / or silicon oxide can be greater than 100% or even greater than 200%, where conformality (%) = side (bottom) thickness / side (top) thickness * 100.

[0086] Now go to Figure 12 According to exemplary embodiments of the present disclosure, a reactor system 1200 is shown. The reactor system 1200 can be used to perform one or more steps or sub-steps as described herein and / or form one or more structures or portions thereof as described herein.

[0087] The reactor system 1200 includes a pair of parallel and facing conductive plate electrodes 4, 2 within the interior 11 (reaction zone) of the reaction chamber 3. Plasma can be excited within the reaction chamber 3 by applying, for example, HRF power (e.g., 100 kHz, 13.56 MHz, 27 MHz, 2.45 GHz, or any value between) from a power source 25 to one electrode (e.g., electrode 4) and electrically grounding the other electrode (e.g., electrode 2). A temperature regulator is located in the lower platform 2 (lower electrode), and the temperature of the substrate 1 placed thereon can be maintained at a desired temperature, such as the substrate temperature described above. Electrode 4 can be used as a gas distribution device, such as a spray plate or spray head. Precursor gases, oxygen and / or nitrogen reactant gases, hydrogen reactant gases, fluorine reactant gases, and dilution / carrier gases (if any) can be introduced into the reaction chamber 3 from sources 21, 22, 20, and 26 and through the spray plate 4 using one or more of gas lines 23, 24, 25, and 27. Although the illustration shows four gas lines 23, 24, 25, and 26, the reactor system 1200 may include any suitable number of gas lines. For example, source 21 may correspond to a silicon precursor source, source 22 may correspond to one or more of an oxygen reactant source and a nitrogen reactant source, source 20 may correspond to a hydrogen reactant source, and source 26 may correspond to a fluorine reactant source.

[0088] In reaction chamber 3, a circular conduit 13 with an exhaust line 7 is provided, through which gas in the interior 11 of reaction chamber 3 can be discharged. Furthermore, a transfer chamber 5 located below reaction chamber 3 is provided with a sealing gas line 24 to introduce sealing gas into the interior 11 of reaction chamber 3 via the interior 16 (transfer zone) of transfer chamber 5, which is provided with a separation plate 14 for separating the reaction zone and the transfer zone (the gate valve through which the substrate is transferred into or out of transfer chamber 5 is omitted in this figure). The transfer chamber is also provided with an exhaust line 6. In some embodiments, the deposition and / or fluorine treatment steps are performed in the same reaction space, allowing two or more (e.g., all) steps to be performed consecutively without exposing the substrate to air or other oxygen-containing atmospheres.

[0089] In some embodiments, continuous flow of carrier gas to reaction chamber 3 can be achieved using a flow-through system (FPS), wherein the carrier gas line is provided with a bypass line having a precursor reservoir (bottle), and the main line and the bypass line are switched, wherein the bypass line is closed when only carrier gas is intended to be supplied to the reaction chamber, and the main line is closed when both carrier gas and precursor gas are intended to be supplied to the reaction chamber, and the carrier gas flows through the bypass line and exits from the bottle together with the precursor gas. In this way, the carrier gas can flow continuously into the reaction chamber, and the precursor gas can be carried in a pulsed manner by switching between the main line and the bypass line, without substantially causing pressure fluctuations in the reaction chamber.

[0090] Reactor system 1200 may include one or more controllers 26, which are programmed or otherwise configured to enable one or more method steps described herein to be performed. As those skilled in the art will understand, controllers 26 are coupled to various power supplies, heating systems, pumps, robots, and airflow controllers or valves of the reactor. For example, controllers 26 may be configured to control the airflow of silicon precursors, nitrogen and / or oxygen reactants, optionally hydrogen reactants, and fluorine reactants into at least one of one or more reaction chambers to form one or more of silicon nitride and silicon oxide layers on a substrate surface.

[0091] In some embodiments, a dual-chamber reactor (for processing two portions or compartments of a substrate disposed close to each other) may be used, wherein the reactive gas and the inert gas may be supplied through a shared pipeline, while the precursor gas may be supplied through a non-shared pipeline.

[0092] The exemplary embodiments disclosed above do not limit the scope of the invention, as these embodiments are merely examples of embodiments of the invention. Any equivalent embodiments are within the scope of the invention. In fact, various modifications to this disclosure, such as alternative and useful combinations of the described elements (e.g., steps), will become apparent to those skilled in the art from the description, in addition to those shown and described herein. Such modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for filling gaps on a substrate surface by depositing one or more of silicon nitride and silicon oxide on the substrate surface, the method comprising the steps of: Fluorine reactants are supplied to the reaction chamber for fluorine reactant pulses to react with the surface of the substrate, such that the growth rate of the subsequently formed material is lower in the top region of the gap than in the rest of the gap; Silicon precursors are supplied to the reaction chamber for silicon precursor pulses; One or more of nitrogen reactants and oxygen reactants are supplied to the reaction chamber for reactant pulses; as well as Hydrogen reactants are supplied to the reaction chamber for hydrogen reactant pulses to promote the deposition of one or more of silicon nitride and silicon oxide in the lower region of the gap.

2. The method according to claim 1, wherein, The silicon precursor includes one or more of silanes, halosilanes, and organosilanes.

3. The method according to claim 2, wherein, The silicon precursor includes the halosilane, and the halosilane includes one or more of the following: dichlorosilane, diiodosilane, hexachlorodisilane, octachlorotrisilane, dibromosilane, tribromosilane, trichlorosilane (HSiCl3), monochlorosilane (H3SiCl), silicon tetrachloride (SiCl4), monobromosilane (H3SiBr), triiodosilane (HSiI3), monoiodosilane (H3SiI), H2Si2I4, H4Si2I2, and H5Si2I.

4. The method according to claim 2, wherein, The silicon precursor includes organosilanes, and the organosilanes include aminosilanes.

5. The method according to claim 2, wherein, The silicon precursor includes heterosilanes.

6. The method according to any one of claims 1-5, wherein, The silicon precursor includes one or more of the following: tris(dimethylamino)silane, bis(tert-butylamino)silane, bis(sec-butylamino)silane, trisilaneamine, neopentyl silane, bis(dimethylamino)silane (DMAS), bis(diethylamino)silane (BDEAS), bis(ethylmethylamino)silane (BEMAS), tetra(dimethylamino)silane (TKDMAS), trimethylsilane (SiH(CH3)3), tetramethylsilane (Si(CH3)4), silane, tetra(ethoxy)silane (TEOS, Si(OC2H5)4), tri(tert-butoxy)silanol (TBOS), tri(tert-pentoxy)silanol (TPSOL), and dimethyldichlorosilane.

7. The method according to any one of claims 1-5, wherein, The nitrogen reactants include one or more of nitrogen (N2), N2O and NO, and / or the oxygen reactants include O2.

8. The method according to any one of claims 1-5, wherein, The method includes supplying the hydrogen reactant to the reaction chamber, and the hydrogen reactant includes one or more of hydrogen (H2), NH3, N2H4, and N2H2.

9. The method according to any one of claims 1-5, wherein, The fluorine reactants include one or more of NF3, CF4, C2F6, SF6, NH2F, C3F8, and F2.

10. The method according to any one of claims 1-5, wherein, The step of providing one or more of nitrogen reactants and oxygen reactants to the reaction chamber includes continuously providing one or more of nitrogen reactants and oxygen reactants, and the continuous provision of one or more of nitrogen reactants and oxygen reactants is performed simultaneously with the step of providing silicon precursors.

11. The method according to claim 10, wherein, The continuous supply of one or more of the nitrogen reactant and the oxygen reactant is performed simultaneously with the steps of supplying the silicon precursor and the steps of supplying the hydrogen reactant and the fluorine reactant.

12. The method according to any one of claims 1-5, wherein, The steps of providing one or more of nitrogen reactants and oxygen reactants and the step of providing hydrogen reactants overlap in the reaction chamber.

13. The method according to any one of claims 1-5, wherein, The steps of providing hydrogen reactants and providing silicon precursors overlap in the reaction chamber.

14. The method according to any one of claims 1-5, wherein, The step of providing the fluorine reactant precedes the step of providing the silicon precursor.

15. The method according to any one of claims 1-5, wherein, The steps of providing hydrogen reactants and providing fluorine reactants do not overlap in the reaction chamber.

16. The method according to any one of claims 1-5, wherein, Plasma is applied during the step of providing one or more of nitrogen reactants and oxygen reactants to form one or more of activated nitrogen substances and activated oxygen substances.

17. The method according to any one of claims 1-5, wherein, Plasma is applied during the step of providing hydrogen reactants to form activated hydrogen material.

18. The method according to any one of claims 1-5, wherein, Plasma is applied during the step of providing fluorine reactants to form activated fluorine substances.

19. The method according to claim 1, wherein, During the step of providing fluorine reactants, the temperature of the substrate is between -20°C and 1000°C.

20. The method according to claim 19, wherein, During the step of providing the fluorine reactants, the temperature of the substrate is between 75°C and 600°C.

21. The method according to claim 18 or 19, wherein, The power used to produce activated fluorine during the step of providing fluorine reactants is between 0W and 10000W.

22. The method according to claim 21, wherein, The power to produce activated fluorine during the step of providing fluorine reactants is between approximately 50 W and approximately 3000 W.

23. The method according to any one of claims 1-5, wherein, The duration of the fluorine reactant pulse is between 0.01 seconds and 600 seconds.

24. The method according to claim 23, wherein, The duration of the fluorine reactant pulse is between 1 second and 300 seconds.

25. The method according to any one of claims 1-5, wherein, During the fluorine reactant pulse, the pressure inside the reaction chamber is between 0.0001 Pa and 101325 Pa.

26. The method of claim 25, wherein, During the fluorine reactant pulse, the pressure in the reaction chamber is between 10 Pa and 13333 Pa.

27. The method according to any one of claims 1-5, wherein, The method includes filling gaps on the substrate surface with one or more of silicon nitride and silicon oxide.

28. The method according to any one of claims 1-5, wherein, The method includes forming a hard mask using one or more of silicon nitride and silicon oxide.

29. A structure formed using the method according to any one of claims 1-28.

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