Method of forming a structure including silicon-carbon material and the structure including silicon-carbon material formed using the method

Abstract

The disclosed invention relates to methods and systems for forming structures comprising silicon-carbon materials, and structures formed using such methods or systems. An exemplary method includes providing a first gas to a reaction space, providing a silicon-carbon precursor to the reaction space, terminating the flow of the silicon-carbon precursor to the reaction space, forming a first plasma within the reaction space to deposit silicon-carbon material on a substrate surface, and optionally treating the silicon-carbon material with an activating agent to form a treated silicon-carbon material.

Description

Technical Field

[0001] This disclosure generally relates to methods for forming structures suitable for use in the manufacture of electronic devices. More specifically, examples of this disclosure relate to methods for forming structures including layers of silicon carbide material, structures of such layers, and systems for performing the aforementioned methods and / or forming the aforementioned structures. Prior Technology

[0002] During the manufacture of devices (such as semiconductor devices), it is often desirable to fill features (e.g., trenches or gaps) on the surface of a substrate having insulating or dielectric materials. Due to its high etch selectivity relative to other materials (such as silicon oxide), silicon-carbon materials may be desired for use in a variety of applications.

[0003] Unfortunately, typical silicon-carbon deposition techniques can result in the formation of voids in the deposited silicon-carbon material, especially when the silicon-carbon material is deposited using plasma-assisted deposition techniques.

[0004] Accordingly, the desired improvement method for forming a structure is specifically for a method of filling gaps on the surface of a substrate with a silicon carbide material, the aforementioned method reducing the formation of voids in the silicon carbide material and / or providing the desired properties of the silicon carbide material.

[0005] Any discussion presented in this section (including discussions of problems and solutions) is included in this disclosure for the purpose of providing context for this disclosure and should not be construed as an admission that any or all of the discussion was known or otherwise constituted prior art at the time of completion of this invention. Summary of the Invention

[0006] The various embodiments disclosed herein relate to methods for forming structures suitable for use in the fabrication of electronic devices (sometimes referred to herein as membrane structures). While the various embodiments of this disclosure address the shortcomings of prior methods and structures in more detail below, generally, the exemplary embodiments of this disclosure provide improved methods for forming structures including silicon carbide materials, structures including silicon carbide materials, and systems for performing the aforementioned methods and / or forming the aforementioned structures. The methods described herein can be used to fill features on the surface of a substrate.

[0007] According to various embodiments of this disclosure, a method for forming a structure is provided, for example, a method for filling a patterned recess on a surface of a substrate. An exemplary method includes providing a substrate containing the patterned recess within a reaction space, providing a first gas to the reaction space, providing a silicon carbide precursor to the reaction space, terminating a flow of the silicon carbide precursor to the reaction space, and forming a first plasma within the reaction space to deposit silicon carbide material on a surface of the substrate. In examples of these embodiments, a flow of the silicon carbide precursor is terminated before the formation of the first plasma. In other examples, the first plasma may be continuous through a plurality of deposition steps and / or a plurality of deposition and processing steps, as described in more detail below. The first gas may include, for example, one or more of Ar, He, NH3, N2, and H2. An exemplary method may additionally include a step of providing a second gas to the reaction chamber. The second gas comprises one or more of Ar, He, NH3, N2, and H2. The first gas and the second gas may be different gases. As explained in more detail below, the various steps of providing the silicon-carbon precursor, providing a first gas, providing a second gas, and forming a plasma may overlap. An exemplary method may also include a step of processing the silicon-carbon material; this processing step may include providing the first gas to the reaction chamber during the step of forming the first plasma and / or during the step of forming a second plasma. The chemical formula of the silicon-carbon precursor may be represented by the formula Si aC bH cN d, where a is a natural number, b is a natural number, c is a natural number, and d is 0 or a natural number. As further explained below, various properties of the silicon-carbon material (such as etching rate, density, composition, and the like) may be manipulated by changing one or more of the first gas, the second gas, and / or another process parameter.

[0008] According to a further exemplary embodiment of the invention, a structure is formed at least in part according to the methods described herein. The structure may include silicon carbide material and / or treated silicon carbide material.

[0009] According to further exemplary embodiments of this disclosure, a system is provided for performing a method as described herein and / or for forming a structure.

[0010] Those skilled in the art will readily understand these and other embodiments from the following detailed description of some embodiments already described with reference to the accompanying drawings; the invention is not limited to any of the specific embodiments disclosed. Simple Explanation of the Diagram

[0011] A more complete understanding of the exemplary embodiments disclosed herein can be derived by referring to the embodiments and the claims, when considered in conjunction with the following illustrative drawings. Figure 1 illustrates a method according to an exemplary embodiment of the present disclosure. Figure 2 illustrates a timing sequence without additional plasma processing steps according to an exemplary embodiment of the present disclosure. Figure 3 illustrates another timing sequence of plasma processing steps according to an exemplary embodiment of the present disclosure. Figure 4 illustrates another timing sequence of plasma processing steps according to an exemplary embodiment of the present disclosure. Figure 5 illustrates a transmission electron microscope image and properties of a silicon carbide material based on the manufacturing process shown in Figures 2, 3 and 4, according to an exemplary embodiment of the present disclosure. Figure 6 illustrates another time sequence based on an example disclosed herein. Figure 7 illustrates a transmission scanning electron microscope image of a silicon carbide material, depending on the type of precursor, according to an exemplary embodiment of this disclosure. Figure 8 illustrates a reactor system according to an exemplary embodiment of the present disclosure. It will be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, some of the elements in the drawings may be enlarged relative to other elements to help improve the understanding of the embodiments illustrated in this disclosure. Implementation

[0012] While certain embodiments and examples are disclosed below, it will be understood by those skilled in the art that the invention extends beyond the specific embodiments and / or uses disclosed herein, as well as their obvious modifications and equivalents. Therefore, it is intended that the scope of the invention disclosed herein not be limited to the specific disclosed embodiments described below.

[0013] This disclosure generally relates to methods for depositing materials, methods for forming structures, structures formed using the aforementioned methods, and systems for performing the aforementioned methods and / or forming the aforementioned structures. As an example, the methods described herein can be used to fill features on the surface of a substrate, such as gaps (e.g., spaces between trenches, vias, or protrusions), with a silicon carbide material. The terms gap and recess are used interchangeably herein.

[0014] To mitigate void and / or seam formation during the gap-filling process, the deposited silicon carbide material may initially be flowable and flow within the gaps to fill them. The initially flowable material may subsequently harden. As described below, in at least some cases, the hardened silicon carbide material can be processed, for example, to densify the material and / or increase its etch resistance. As further described below, various silicon carbide material properties can be tuned by adjusting one or more parameters (such as the first gas and / or the second gas used during the deposition and / or processing steps).

[0015] The exemplary structures described herein can be used in a variety of applications, including but not limited to: cell isolation in 3D cross-point memory devices, self-aligned vias, dummy gates, inverted patterns, PC RAM isolation, cut hard masks, DRAM storage node contact (SNC) isolation, and the like.

[0016] In this disclosure, "gas" can refer to materials, vaporized solids, and / or vaporized liquids that are gaseous at room temperature and pressure, and may consist of a single gas or a mixture of gases depending on the context. Gases other than process gases, i.e., gases introduced without passing through gas distribution assemblies such as spray heads, other gas distribution devices, or the like, can be used, for example, to seal reaction spaces, including sealing gases such as rare gases. In some cases, such as in the context of material deposition, the term "precursor" can refer to a compound that participates in a chemical reaction that produces another compound, and specifically refers to a compound that constitutes the membrane matrix or the main framework of the membrane, while the term "reactant" can refer (in some cases other than precursors) to a compound that activates, modifies, or catalyzes a precursor reaction; reactants may provide elements (such as H) to the membrane matrix and become part of the membrane matrix when power (e.g., radio frequency (RF) power) is applied, for example. In some cases, the terms precursor and reactant are used interchangeably. The term "inert gas" refers to a gas that, when power is applied (e.g., RF power), does not participate in the chemical reaction to a perceptible extent and / or excites the precursor (e.g., promotes precursor polymerization), but unlike reactants, the inert gas cannot become part of the membrane matrix to a perceptible extent.

[0017] As used herein, the term "substrate" can refer to any underlying material(s) on which devices, circuits, or films can be formed or on which they are formed. Substrate can include bulk materials (such as silicon (e.g., single-crystal silicon)), other group IV materials (such as germanium), or compound semiconductor materials (such as group III-V or group II-VI semiconductors), and can include one or more layers overlying or underlying the bulk material. Furthermore, substrate can include various features such as gaps (e.g., recesses or vias), lines or protrusions (e.g., lines having gaps formed between them), and the like, which are formed on or within at least a portion of a layer or bulk material of the substrate. For example, one or more features (e.g., recesses) can have a width of about 10 nm to about 100 nm, a depth or height of about 30 nm to about 1,000 nm, and / or an aspect ratio of about 3.0 to 100.0.

[0018] In some embodiments, "film" refers to a layer extending in a direction perpendicular to the thickness direction. In some embodiments, "layer" refers to a material formed on a surface having a certain thickness, and may be synonymous with membrane or non-membrane structures. 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 be clear or indistinct, 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. A layer or membrane may be continuous or discontinuous. Furthermore, multiple deposition cycles and / or multiple deposition and processing cycles may be used to form a single membrane or layer.

[0019] As used herein, the terms "silicon-carbon layer" or "silicon-carbon material" may refer to a layer whose chemical formula can be represented as including silicon and carbon. Layers containing silicon-carbon material may include other elements, such as one or more of nitrogen and hydrogen.

[0020] As used herein, the term "structure" can refer to a device structure that has been partially or completely fabricated. For example, a structure can be a substrate or a substrate having one or more layers and / or features formed thereon.

[0021] As used herein, the term "cyclic deposition process" can refer to a vapor deposition process in which deposition cycles (typically multiple successive deposition cycles) are performed in a process chamber. Cyclic deposition processes can include cyclic chemical vapor deposition (CVD) and atomic layer deposition processes. A cyclic deposition process can include one or more cycles, which(e.g.) include plasma activation of precursors, reactants, and / or inert gases.

[0022] In this disclosure, in some embodiments and depending on the context, "continuously" or "continuous" may mean without breaking the vacuum, without interruption of the timeline, without any substantial intervention steps, without changing the processing conditions, immediately following, as the next step, or between two structures without the intervention of discrete physical or chemical structures other than the two structures.

[0023] Liquidity (e.g., initial liquidity) can be determined as follows: Table 1 Bottom / Top Ratio (B / T) Liquidity 0 < B / T < 1 none 1 ≤ B / T < 1.5 bad 1.5 ≤ B / T < 2.5 good 2.5 ≤ B / T < 3.5 very good 3.5≤ B / T Excellent The B / T ratio refers to the ratio of the film thickness deposited at the bottom of the recess before it is filled to the film thickness deposited on the top surface forming the recess. Generally, flowability is evaluated using wide recesses with an aspect ratio of about 1 or less, because generally, the higher the aspect ratio of the recess, the higher the B / T ratio. When the aspect ratio of the recess is high, the B / T ratio generally becomes higher. As used herein, "flowable" membranes or materials exhibit good or better flowability.

[0024] When volatile silicon-carbon precursors are polymerized and deposited onto a substrate surface, for example by plasma polymerization, a temporary flowability of the film can be achieved. This is achieved by activating or splitting the gaseous precursors using energy provided by plasma gas discharge to initiate polymerization. The resulting polymer material may exhibit temporarily flowable behavior. Once the deposition step is complete and / or after a short period of time (e.g., approximately 3.0 seconds), the film may cease to flow and instead solidify, thus eliminating the need for a separate curing process.

[0025] In this disclosure, any two numbers of a variable may constitute the working range of the variable, and any indicated range may include or exclude endpoints. Additionally, any numerical value of the indicated variable (regardless of whether the value is indicated as "about") may refer to an exact value or an approximate value and include equivalent values, and in some embodiments may refer to an average value, median value, representative value, multi-value, etc. Furthermore, in this disclosure, in some embodiments, the terms "including," "constituted by," and "having" may independently mean "typically or broadly comprising," "comprising," "consisting essentially of," or "consisting of." In this disclosure, any defined meaning does not necessarily exclude the common and conventional meanings in some embodiments.

[0026] Turning now to the figures, Figure 1 illustrates method 100 according to an example of this disclosure. Method 100 can be used to fill one or more patterned recesses on the surface of a substrate. Method 100 may be or may include a plasma-enhanced chemical vapor deposition (PECVD) process, or a plasma-enhanced atomic layer deposition (PEALD) process, or a combination of PECVD and PEALD processes. In some cases, method 100 may be a cyclic deposition process. Method 100 can be used to form a silicon-carbon material having an etch selectivity greater than 50 relative to silicon oxide (e.g., SiO₂) and / or an etch selectivity greater than 20 relative to silicon nitride (e.g., Si₃N₄).

[0027] As illustrated, method 100 includes the following steps: providing a substrate within a reaction space (step 102); providing a first gas to the reaction space (step 104); providing a second gas to the reaction space (step 106); providing a silicon carbide precursor to the reaction space (step 108); terminating the flow of the silicon carbide precursor to the reaction space (step 110); and forming a first plasma within the reaction space to deposit silicon carbide material on the surface of the substrate (step 112). According to a specific embodiment of this disclosure, the substrate includes one or more features, such as recesses. Method 100 may also include (e.g., plasma) processing steps (step 114).

[0028] During step 102, the substrate is provided into the reaction space of the vapor phase reactor. According to examples disclosed herein, the reaction space may form part of a circulating deposition reactor, such as an atomic layer deposition (ALD) reactor (e.g., PEALD) or a chemical vapor deposition (CVD) reactor (e.g., PECVD). The various steps of the methods described herein may be performed in a single reaction chamber or in multiple reaction chambers, such as the reaction chamber of a cluster tool.

[0029] During step 102, the substrate may be brought to a desired temperature, and / or the reaction chamber may be brought to a desired pressure, such as a temperature and / or pressure suitable for subsequent steps. For example, the temperature within the reaction chamber (e.g., the substrate or substrate support) may be less than or equal to 100°C (e.g., from about 23°C to about 100°C). The pressure within the reaction chamber may range from about 200 Pa to about 1,250 Pa.

[0030] During step 104, a first gas comprising one or more gases, either separately or in any mixture thereof, is supplied to the reaction space, such as one or more of argon (Ar), helium (He), ammonia (NH3), nitrogen (N2), and hydrogen (H2). As a specific example, the first gas system may be hydrogen or include hydrogen. The flow rate of the first gas to the reaction chamber during this step may be from about 200 sccm to about 3,000 sccm.

[0031] During step 106, a second gas comprising one or more gases, either separately or in any mixture thereof, is provided to the reaction space, such as one or more of argon (Ar), helium (He), ammonia (NH3), nitrogen (N2), and hydrogen (H2). The second gas may be different from the first gas. For example, at least one of the first and second gases may be different. As a specific example, the second gas system is argon and / or helium, or includes argon and / or helium. The mixture of argon and helium may range from about 0 to about 50 vol.% argon and / or helium. The flow rate of the second gas to the reaction space during this step may range from about 10 sccm to about 2,000 sccm. As described in more detail below, the second gas may be used to facilitate plasma ignition within the reaction space, to remove reactants and / or byproducts from the reaction chamber, and / or as a process gas. According to various embodiments of this disclosure, steps 104 and 106 may at least partially overlap.

[0032] During step 108, a precursor for forming the silicon-carbon material layer is introduced into the reaction space. Exemplary silicon-carbon precursors include compounds represented by the formula Si aC bH cN d, where a is a natural number, b is a natural number, c is a natural number, and d is 0 or a natural number. For example, a can range from 1 to 5, b from 1 to 20, c from 1 to 40, and d from 0 to 5. Silicon-carbon precursors can include chain or cyclic molecules having two or more carbon atoms, one or more silicon atoms, and one or more hydrogen atoms (such as molecules represented by the above formula). As a specific example, the precursor may be or may include one or more cyclic (e.g., aromatic) structures and / or compounds having at least one double bond.

[0033] Referring temporarily to FIG7, (a) structure 702 is illustrated, which includes a substrate 704 (with gaps 706 formed therein) and a silicon-carbon layer 708 covering the surface 710 of the substrate 704. In FIG7, (b) structure 712 is illustrated, which includes a substrate 714 (with gaps 716 formed therein) and a silicon-carbon layer 718 covering the surface 720 of the substrate 714. The deposition conditions of structures 702 and 712 are the same, except that the precursor used to form structure 702 is hexamethyldisilane and the precursor used to form structure 712 is dimethyldivinylsilane (DMDVS). Compared with layer 708 of structure 702, structure 712 has fewer voids in silicon-carbon layer 718, indicating that the use of a precursor having at least one carbon (e.g., carbon-carbon) double bond can be beneficial in filling the recesses while reducing any void formation. Therefore, based on the examples disclosed herein, silicon-carbon precursors contain one or more double bonds.

[0034] Based on some examples disclosed herein, the chemical formula of silicon-carbon precursors can be represented by the following formula: R 1R 4 │ │ R 2── S i── S i── R 5 │ │ R 3R 6 R1 to R6 are independently selected from (C1-C10) alkyl, olefin, or aryl and H. In a particular example, each of R1 to R6 may include a methyl group represented by the following chemical formula. CH 3CH 3 │ │ CH 3── S i── S i── CH 3 │ │ CH 3CH 3

[0035] Based on other examples disclosed herein, the chemical formula of silicon-carbon precursors can be represented by the following formula: R 2 │ R 1── S i── R 3 │ R 4 R1 to R4 are independently selected (e.g., C1 to C10) from alkyl, olefin, or aryl groups and H. For example, the chemical formula can be represented by: CH 3 │ CH 2══ CH ── S i── CH ══ CH 2 │ CH 3

[0036] The flow rate of the silicon-carbon precursor from the source to the reaction chamber can vary depending on other process conditions. For example, the flow rate can range from about 100 sccm to about 3,000 sccm. Similarly, the duration of each step in supplying the silicon-carbon precursor to the reaction chamber can vary depending on various considerations. For example, the duration can range from about 1.0 second to about 35.0 seconds.

[0037] During step 110, the flow of silicon-carbon precursor into the reaction space is reduced or terminated. During a subsequent period after step 110, the concentration of silicon-carbon precursor in the reaction space may be reduced. In some cases, the flow of silicon-carbon precursor may be reduced for various steps without complete shutdown.

[0038] During step 112, for example, after step 110, plasma may be formed. Alternatively, plasma may be formed before steps 108 and 110. The plasma may be direct plasma. The power used to ignite and sustain the plasma may range from about 50 W to about 800 W. The frequency range of the power may range from about 0.4 MHz to about 27.12 MHz. At the end of step 112, the plasma may be terminated, for example by reducing or extinguishing the power used to generate the plasma.

[0039] During step 112, the silicon-carbon precursor system is converted into an initial viscous material using an excited species. The initial viscous silicon-carbon material can flow into at least one recess and can be converted into silicon-carbon material, for example, through further reaction with the excited species. The silicon-carbon material can be converted into a solid or substantially solid state.

[0040] One or more of steps 104 to 112 may be repeated to form a silicon-carbon material of the desired thickness.

[0041] As mentioned above, method 100 may also include a processing step 114. Processing step 114 can be used to densify the silicon-carbon material. Step 114 may include, for example, treating the silicon-carbon material with an activating agent to form a treated silicon-carbon material. Step 114 may include forming agents, such as the second gas provided during step 106. The power used to form the plasma during step 114 can range from about 50 W to about 800 W. The frequency range of the power can range from about 0.4 MHz to about 27.12 MHz.

[0042] According to the exemplary embodiments disclosed herein, during step 114, the activated species are formed using plasma (e.g., radio frequency and / or microwave plasma). Direct plasma and / or distal plasma can be used to form the activated species. In some cases, a gas (e.g., a second gas) may be continuously flowed into the reaction space during one or more steps, and the activated species are periodically formed by circulating the power used to form the plasma. The temperature in the reaction chamber during step 114 may be less than or equal to 100°C. The pressure in the reaction chamber during the formation of the species for the treatment may be from about 300 Pa to about 2,000 Pa. The species formation for the treatment step may be formed in the same reaction chamber used for one or more or other steps, or it may be in separate reaction chambers (such as another reaction chamber of the same clustering tool). Furthermore, as illustrated, method 100 may include a repeating loop that includes steps 104 to 114.

[0043] As mentioned above and elsewhere in this article, the steps of the methods described herein may overlap and need not be performed in the order mentioned above. Furthermore, in some cases, various steps or combinations of steps may be repeated one or more times before the method proceeds to the next step.

[0044] Figures 2 through 4 and 6 illustrate examples of pulse timing sequences used in the methods according to exemplary embodiments of the present disclosure. For example, the timing sequences illustrated in Figures 2 through 4 and 6 can be used in conjunction with method 100.

[0045] Figures 2 through 4 and 6 schematically illustrate a first gas, a second gas, a silicon carbide precursor, and a plasma power pulse, wherein the gas and / or plasma power are supplied to the reactor system or reaction space for a sustained pulse duration. The pulse width may not necessarily indicate the amount of time associated with each pulse; the illustrated pulses may indicate the relative start and / or end times of each pulse. Similarly, the height may not necessarily indicate a specific amplitude or value, but may show relative high and low values. The process conditions used for each pulse duration can be described above in conjunction with the corresponding steps of method 100. The examples below are illustrative only and are not intended to limit the scope of this disclosure or the claims.

[0046] Figure 2 illustrates a timing sequence 200 according to an example of this disclosure. The timing sequence 200 includes a plurality of silicon-carbon material deposition and processing cycles 1 to N. According to examples of these embodiments, N can range from about 1 to about 50.

[0047] In the example illustrated in Figure 2, a first gas is supplied to the reaction space for a continuous pulse period 202, and a second gas is supplied to the reaction chamber for a continuous pulse period 204. The pulse periods 202 and / or 204 can range from about 5.0 to about 100.0 seconds, and can be the same or different, and / or can vary with individual deposition cycles.

[0048] After pulse periods 202 and / or 204 are initiated, the silicon-carbon precursor is supplied to the reaction chamber for a sustained pulse period 206. The pulse period 206 may range from, for example, about 1.0 second to about 35.0 seconds. Each pulse period 206 may be the same or vary in time. As illustrated, pulse periods 202, 204, and 206 may overlap. For example, pulse period 206 may begin after pulse periods 202 and / or 204 and may end before pulse periods 202 and / or 204.

[0049] After the flow of the silicon-carbon precursor to the reaction chamber has terminated at t1, power for plasma formation is provided for a sustained pulse period 208. The power during the pulse period 208 (e.g., applied to the electrodes) can range from about 100 W to about 800 W, or as otherwise mentioned herein. The frequency of the power can range from about 0.4 MHz to about 27.12 MHz, or as otherwise mentioned herein.

[0050] Pulse period 206 may end at t2, during which most or substantially all (e.g., 90% or more) of the silicon carbide precursor present at t1 is removed from the reaction space. Pulse period 208 may begin before t2 and after t1. Thus, in the illustrated example, the first gas, the second gas, and the silicon carbide precursor are present in the reaction chamber when the plasma is ignited / formed at the beginning of pulse period 208. The range of pulse period 208 may be, for example, from about 1.0 second to about 30.0 seconds. Each pulse period 208 may be the same or vary in time.

[0051] As illustrated in this example, pulse periods 202 and 204 may begin and / or terminate at approximately or substantially the same time (e.g., within 10, 5, 2, 1, or 0.5 percent of each other). Once the flow of the silicon-carbon precursor into the reaction chamber has ceased, a flushing period or flushing pulse may be initiated using a first gas and / or a second gas from the reaction space to flush the silicon-carbon precursor. Flushing may be further assisted by a vacuum pump and may continue after steps 202 and / or 204. The flushing period may range, for example, from about 5.0 seconds to about 30.0 seconds. The flushing periods may be the same or vary in time.

[0052] The timing sequence 200 may also include a processing step that may begin at approximately t2 and end at the end of plasma pulse 208. In the illustrated example, both the first gas and the second gas are provided during the processing step. In other examples, the second gas may be provided only during the processing step.

[0053] Figure 3 illustrates another timing sequence 300 according to an example of this disclosure. Timing sequence 300 is similar to timing sequence 200, except that the processing step / pulse period in at least one deposition cycle is longer than the processing pulse period of timing sequence 200.

[0054] The timing sequence 300 includes a plurality of silicon-carbon material deposition cycles i...n. Furthermore, the timing sequence 300 includes processing steps T1...Tn, which, together with the deposition steps, are represented by deposition and processing steps or cycles 1...N. According to examples of these embodiments, n can range from about 1 to about 50, and N can range from about 1 to about 50.

[0055] The timing sequence 300 may include supplying a first gas and a second gas (e.g., continuously) to the reaction chamber during one or more deposition and processing steps 1...N. In the illustrated example, the first gas is supplied to the reaction chamber for a pulse period 302, and the second gas is supplied to the reaction chamber for a pulse period 304. Pulse periods 302 and 304 may overlap. For example, pulse periods 302 and 304 may begin and / or end at approximately the same time. Pulse periods 302 and / or 304 may begin before pulse periods 306 and / or 308 described below, and may continue until the end of at least one pulse period 308. The first gas and / or the second gas may be used to facilitate flushing of the reaction space between deposition steps and / or deposition and processing steps, and / or to facilitate plasma formation during the deposition and / or processing of silicon carbide materials.

[0056] Pulse durations 302 and / or 304 may be the same as or similar to pulse durations 202 and 204 described above; the range of pulse durations 302 and 304 may be from about 10.0 to about 100.0 seconds, and may be the same or different, and / or may vary with individual processing and deposition cycles.

[0057] During pulse period 306, a silicon carbide precursor is provided to the reaction space for pulsation. The range of pulse period 306 may be, for example, from about 1.0 second to about 5.0 seconds. Similar to pulse period 206, pulse period 306 may be stopped at t1, and the silicon carbide precursor may be substantially removed at t2.

[0058] After the flow of the silicon-carbon precursor to the reaction chamber has terminated at t1, power for plasma formation is provided for a continuous pulse period 308. Therefore, the flow of the silicon-carbon precursor is terminated before the plasma is ignited / formed.

[0059] The deposition step can begin when the plasma is ignited and end when the silicon-carbon precursor is substantially dissipated from the reaction space at t2.

[0060] The processing steps (T1-Tn) can be performed using the remainder of pulse 308. In this case, the processing steps can begin at t2 and end at the end of pulse 308.

[0061] The power level and pressure within the reaction chamber can be described above along with pulse 208. The pulse duration 308 can range from, for example, about 1 second to about 30 seconds. Each pulse duration 308 can be the same or vary in time.

[0062] Following pulse period 308, the reaction chamber may be flushed for a continuous pulse period. The range of flushing pulse periods may be, for example, from about 10 seconds to about 70 seconds. The flushing pulse periods may be the same or vary in time.

[0063] Figure 4 illustrates another timing sequence 400 according to an additional example of this disclosure. Timing sequence 400 is similar to timing sequence 300, except that timing sequence 400 includes separate, non-overlapping deposition and processing plasma pulses 408 and 409, instead of a continuous plasma pulse 308. Furthermore, timing sequence 400 includes separate second gas pulses 404 and 405, instead of a continuous pulse 304. And, sequence 400 does not include the supply of a first gas during the processing step / pulse period.

[0064] The timing sequence 400 includes a plurality of silicon-carbon material deposition cycles i...n. Furthermore, the timing sequence 400 includes processing steps, which, together with the deposition steps, are represented by deposition and processing steps or cycles 1...N. According to examples of these embodiments, n can range from about 1 to about 50, and N can range from about 1 to about 50.

[0065] The first gas pulse 402 and the second gas pulse 404 may be the same as or similar to the first gas pulse 202 and the second gas pulse 204 described above together with Figure 2. The first gas pulse 402 and the second gas pulse 404 may overlap, may start and / or end at approximately the same time, and / or may have approximately the same duration.

[0066] Similarly, silicon carbide precursor pulse 406 may be the same as or similar to silicon carbide precursor pulse 206 or 306. Furthermore, plasma pulse 408 may be the same as or similar to plasma pulse 208.

[0067] The range of the second gas pulse 405 can be from about 1.0 second to about 90.0 seconds. The flow rate of the second gas can be described as in conjunction with pulses 204 and 304. As shown in Figure 4, the second gas pulse 405 can begin after the end of plasma pulse 408 and before the start of plasma pulse 409. The second gas pulse 405 can end after plasma pulse 409.

[0068] The conditions of plasma pulse 409 may be the same as or similar to those of plasma pulses 308 and / or 408. Alternatively, the power level may be increased during plasma pulse period 408 compared to the power used during plasma pulse period 408. The power applied during pulse period 409 may range from about 100 W to about 800 W. The frequency range of the power may range from about 0.4 MHz to about 27.12 MHz.

[0069] Figure 5 illustrates illustrative transmission electron microscope (TEM) images of features filled with time sequences 200, 300, and 400. The following process conditions were used. Sequence 200 / 300 / 400 illustrative range Silicon carbide precursors dimethyldivinylsilane (Dimethyldivinylsilane) See above First Gas Hydrogen (0 to 50%) Ar or He (50 to 100%) One or more of Ar, He, NH3, N2 and H2 Second gas Hydrogen (0 to 50%) Ar or He (50 to 100%) One or more of Ar, He, NH3, N2 and H2 Substrate temperature Same as the right 23 to 100 °C Reaction space pressure used for deposition Same as the right 300 Pa to 2,000 Pa Reaction space pressure used for processing Same as the right 300 Pa to 2,000 Pa Plasma power used for deposition 50 to 500 W Same as left Plasma power used for deposition 50 to 3,000 W Same as left Deposition pulse period ON_0.5 to 5.0 seconds OFF_3.0 to 10.0 seconds Same as left Processing pulse period ON_1.0 to 90.0 seconds OFF_3.0 to 150.0 seconds Same as left

[0070] As illustrated in Figure 5, silicon carbide deposited using sequence 300 and sequence 400 exhibits less shrinkage and a lower etch rate compared to silicon carbide deposited using sequence 200 (without a processing step or with a relatively short processing step). Furthermore, compared to silicon carbide treated only with a second gas, silicon carbide treated with a second gas (e.g., hydrogen) in addition to the first gas during the processing steps produces silicon carbide with higher etch resistance. Therefore, the properties of the silicon carbide can be manipulated by controlling the processing time and / or the gas (first gas and / or second gas) provided during the processing pulse.

[0071] Figure 6 illustrates another timing sequence 600 according to an example of this disclosure. Timing sequence 600 is similar to timing sequence 200, except that the power plasma step is continuous through one or more deposition and processing steps.

[0072] The timing sequence 600 includes a plurality of silicon-carbon material deposition cycles i...n. Furthermore, the timing sequence 600 includes processing steps T1...Tn, which, together with the deposition steps, are represented by deposition and processing steps or cycles 1...N. According to examples of these embodiments, n can range from about 1 to about 200, and N can range from about 1 to about 200.

[0073] The timing sequence 600 may include supplying a first gas and a second gas (e.g., continuously) to the reaction chamber during one or more deposition and processing steps 1...N. In the illustrated example, the first gas is supplied to the reaction chamber for a pulse period 602, and the second gas is supplied to the reaction chamber for a pulse period 604. Pulse periods 602 and 604 may overlap. For example, pulse periods 602 and 604 may begin and / or end at approximately the same time. Pulse periods 602 and / or 604 may begin before pulse periods 606 and / or 608 as described below, and may continue until the end of at least one pulse period 608. The first gas and / or the second gas may be used to facilitate flushing of the reaction space between deposition steps and / or deposition and processing steps, and / or to facilitate plasma formation during the deposition and / or processing of silicon carbide materials.

[0074] Pulse periods 602 and / or 604 may be the same as or similar to pulse periods 202 and 204 described above; the range of pulse periods 602 and 604 may be from about 10.0 to about 100.0 seconds, and may be the same or different, and / or may vary with individual processing and deposition cycles.

[0075] During pulse period 606, a silicon carbide precursor is provided to the reaction space for pulsation. The pulse period 606 can range from, for example, about 0.01 seconds to about 10.00 seconds. Similar to pulse period 206, pulse period 606 can terminate at t1, and the silicon carbide precursor can be substantially removed at t2.

[0076] A power pulse duration 608 is provided for forming the plasma. In the illustrated example, the plasma power may be continuous throughout a deposition and processing step or during multiple deposition and processing steps.

[0077] In this case, the deposition step can begin when the silicon-carbon precursor is provided to the reaction chamber and can end when the silicon-carbon precursor has substantially dissipated from the reaction space at t2.

[0078] The processing steps (T1-Tn) can be performed using the remainder of pulse 608 (between silicon carbide precursor pulses 606). In this case, the processing steps can begin at t2 and end at the start of pulse 606.

[0079] The power level and pressure in the reaction chamber during sequence 600 can be described above in conjunction with pulse 208. The pulse duration 608 can range, for example, from about 1 second to about 5,000 seconds.

[0080] After pulse period 608, the reaction chamber can be flushed for a continuous pulse period. The range of the flushing pulse period can be, for example, from about 1 second to about 10 seconds.

[0081] Figure 8 illustrates a reactor system 800 according to an exemplary embodiment of the present disclosure. The reactor system 800 can be used to perform one or more steps or sub-steps as described herein, and / or to form one or more structures or portions thereof as described herein.

[0082] The reactor system 800 includes a pair of parallel, mutually facing conductive plate electrodes 4, 2 within the interior 11 (reaction space) of the reaction chamber 3. Plasma can be generated within the reaction chamber 3 by applying, for example, HRF power (e.g., 13.56 MHz or 27 MHz) 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 can be provided in the lower platform 2 (lower electrode), and the temperature of the substrate 1 placed thereon can be maintained at a desired temperature. Electrode 4 can act as a gas distribution device (such as a spray plate). One or more of gas lines 20, 21, and 22 can be used, and a first gas, a second gas, a dilution gas (if present), a precursor gas, and / or the like can be introduced into the reaction chamber 3 via the spray plate 4. Although illustrated with three gas lines, the reactor system 800 may include any suitable number of gas lines.

[0083] In the reaction chamber 3, a circular pipe 13 with an exhaust line 7 is provided to discharge gas from the interior 11 of the reaction chamber 3. Furthermore, a sealing gas line 24 is provided via a transfer chamber 5 located below the reaction chamber 3 to introduce sealing gas into the interior 11 of the reaction chamber 3 via the interior 16 (transfer zone) of the transfer chamber 5, which includes a partition plate 14 for separating the reaction zone and the transfer zone (a gate valve is omitted in this diagram; the wafer is transferred to or from the transfer chamber 5 through this gate valve). The transfer chamber also has an exhaust line 6. In some embodiments, the deposition and processing steps are performed in the same reaction space so that two or more (e.g., all) of the aforementioned steps can be performed continuously without exposing the substrate to air or other oxygen-containing atmospheres.

[0084] In some embodiments, continuous flow of inert or 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 bypass line are switched such that the bypass line is closed when only carrier gas is intended to be fed into the reaction chamber, and the main line is closed when both carrier gas and precursor gas are intended to be fed into 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 pulses by switching between the main line and the bypass line without substantially fluctuating the reaction chamber pressure.

[0085] As those skilled in the art will understand, the apparatus includes one or more controllers 26 planned or otherwise configured to perform one or more method steps as described herein. As those skilled in the art will understand, the controllers communicate with various power sources, heating systems, pumps, robots, gas flow controllers, or valves of the reactor.

[0086] In some embodiments, a dual-chamber reactor (two sections or compartments configured close to each other for processing wafers) may be used, wherein reactant gases and rare gases are supplied via a common pipeline, while the precursor gas system is supplied via a separate pipeline.

[0087] The examples and embodiments described above do not limit the scope of the invention, as these embodiments are merely examples of embodiments of the invention. Any equivalent embodiments are intended to fall within the scope of the invention. In fact, in addition to what is shown and described herein, those skilled in the art will understand from this specification various modifications to the disclosure (such as substitutions of described elements in combination). Such modifications and embodiments are also intended to fall within the scope of the appended claims.

[0088] 2: Flat plate electrode 3: Reaction Chamber 4: Flat electrode / spray plate 6,7: Exhaust pipes 11: Internal 13: Round tube 20, 21, 22: Gas pipelines 26: Controller 100: Method 102, 104, 106, 108, 110, 112, 114: Steps 200, 300, 400, 600: Time series 202,204,206,208,302,304,306,308,602,604,606,608: Pulse periods 402: First gas pulse 404, 405: Second gas pulse 406: Silicon-Carbon Precursor Pulse 408, 409: Plasma pulse 702, 712: Structure 704, 714: Substrate 706, 716: Gap 708, 718: Silicon-carbon layer 710, 720: Surface 800: Reactor System T1 to Tn: Processing steps

Claims

1. A method for filling a patterned recess on a surface of a substrate, the method comprising the steps of: providing a substrate including the patterned recess in a reaction space; providing a first gas to the reaction space; providing a silicon carbide precursor to the reaction space; terminating the flow of the silicon carbide precursor to the reaction space; and forming a first plasma in the reaction space to deposit a silicon carbide material on a surface of the substrate, wherein the step of providing the first gas and the step of providing the silicon carbide precursor overlap.

2. The method as described in claim 1, wherein the first gas comprises one or more of Ar, He, NH3, N2 and H2.

3. The method as described in claim 1, further comprising a step of providing a second gas to the reaction space.

4. The method as described in claim 3, wherein the second gas comprises one or more of Ar, He, NH3, N2 and H2, and wherein the first gas is different from the second gas.

5. A method for filling a patterned recess on a surface of a substrate, the method comprising the steps of: providing a substrate including the patterned recess in a reaction space; providing a first gas to the reaction space; providing a second gas to the reaction space; providing a silicon carbide precursor to the reaction space; terminating the flow of the silicon carbide precursor to the reaction space; and forming a first plasma in the reaction space to deposit a silicon carbide material on the surface of the substrate, wherein the step of providing the first gas and the step of providing the second gas overlap.

6. The method as described in claim 1, comprising a processing step of the silicon-carbon material, wherein the processing step includes providing the first gas to the reaction space during the step of forming the first plasma.

7. The method as described in claim 3, comprising a processing step of the silicon-carbon material, wherein the processing step includes providing the second gas to the reaction space during a step of forming a second plasma.

8. The method as described in claim 7, wherein the first plasma and the second plasma do not overlap.

9. The method as described in any one of claims 1 to 8, wherein the method comprises a plasma-enhanced chemical vapor deposition (PECVD) process, or a plasma-enhanced atomic layer deposition (PEALD) process, or a combination of a PECVD and a PEALD process.

10. The method as described in claim 9, wherein PECVD includes a method of supplying radio frequency pulses with a continuous precursor or supplying precursor pulses with a continuous radio frequency.

11. The method as described in any one of claims 1 to 8, wherein the chemical formula of the silicon-carbon precursor is represented by the formula SiaCbHcNd, wherein a is a natural number from 1 to 5, b is a natural number from 1 to 20, c is a natural number from 1 to 40, and d is 0 or a natural number from 1 to 5.

12. The method as described in any one of claims 1 to 8, wherein the chemical formula of the silicon-carbon precursor contains one or more double bonds.

13. The method as described in any one of claims 1 to 8, wherein the chemical formula of the silicon-carbon precursor is represented by the following formula: R1 R4 │ │ R2 ── Si ── Si ── R5 │ │ R3 R6 where R1 to R6 are independently selected from alkyl, olefin, or aryl and H.

14. The method as described in any one of claims 1 to 8, wherein the chemical formula of the silicon-carbon precursor is represented by the following formula: R2 │ R1 ── Si── R3 │ R4 wherein R1 to R4 are independently selected from alkyl, olefin, or aryl and H.

15. The method as described in any one of claims 1 to 8, wherein the silicon-carbon precursor comprises one or more of the following: CH3CH3 │ │ CH3 ── Si ── Si ── CH3 │ │ CH3CH3 and CH3 │ CH2══ CH ── Si ── CH ══ CH2. │ CH3 16. The method as described in any one of claims 1 to 8, wherein a temperature within the reaction space is below 100 °C.

17. The method as described in any one of claims 1 to 8, wherein a pressure within the reaction space is between 300 Pa and 2,000 Pa.

18. The method as described in claim 3 or claim 5, wherein the properties of the silicon-carbon material are manipulated by changing one or more of the first gas and the second gas.

19. The method as described in any one of claims 1 to 8, wherein the etch selectivity of the silicon-carbon material relative to silicon oxide is greater than 50.

20. The method as described in any one of claims 1 to 8, wherein the etching selectivity of the silicon-carbon material relative to silicon nitride is greater than 20.

21. A structure comprising a silicon-carbon material, formed by the method described in any one of claims 1 to 20.

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