Method of forming a structure comprising a silicon carbonitride layer

Abstract

A method of forming a structure including a silicon carbon nitride layer is disclosed. An exemplary method includes using high frequency power during deposition of the silicon carbon nitride layer to form a film having desired properties. In some cases, a continuous plasma is used to form the silicon carbon nitride layer and a carbon silicon oxynitride layer.

Description

Technical Field

[0001] This disclosure generally relates to methods for forming thin films and structures including thin films. More specifically, this disclosure relates to methods for forming structures including layers comprising silicon, carbon, and nitrogen, and to structures including such layers. Background Technology

[0002] Silicon nitride materials (such as those containing silicon carbonitride (SiCN)) can be used in a variety of applications. For example, during the fabrication of electronic devices, such materials can be used to form insulating layers, etch stop layers, and / or spacers.

[0003] For various applications, relatively robust resistance to wet etching processes, such as wet etching using hydrofluoric acid and / or hot phosphoric acid, and / or ashing processes, may be desired. Furthermore, a relatively low dielectric constant may be desirable. While SiCN can exhibit the desired dielectric constant, it may not exhibit the desired etch-stopping properties.

[0004] Silicon nitride materials (such as silicon oxycarbonitride (SiOCN)) can exhibit desired etch rates or etch stop and / or ashing resistance. However, SiOCN may not exhibit the desired dielectric constant. Furthermore, the deposition of SiOCN on the substrate surface can lead to undesirable oxidation of the substrate surface.

[0005] For many applications, it may be desirable to deposit SiCN and / or SiOCN on the surface of a substrate at relatively low temperatures (e.g., below 650°C). Plasma-enhanced chemical vapor deposition (PECVD) can be used to deposit SiCN and / or SiOCN layers on the substrate surface at relatively low temperatures.

[0006] Typical PECVD techniques for depositing SiCN and / or SiOCN layers involve the use of silicon precursors and reactants. The reactants are typically used to form a plasma. The activating material from the plasma reacts with the silicon precursor to form SiCN and / or SiOCN. While these techniques work well for some applications, the properties of SiCN and / or SiOCN layers formed using activating materials formed with typical plasma formation techniques may not allow for the desired combination of etch selectivity, dielectric constant, density, and / or other properties. Additionally, or alternatively, such techniques can be relatively time-consuming. Therefore, improved methods for forming structures comprising SiCN and / or SiOCN are desired.

[0007] Any discussion set forth in this section (including discussions of problems and solutions) is included in this disclosure and is for the purpose of providing background to this disclosure only. Such discussion should not be construed as an admission that any or all information was known at the time of making this invention or otherwise constitutes prior art. Summary of the Invention

[0008] Various embodiments of this disclosure relate to methods for forming structures including silicon carbonitride layers. While various embodiments of this disclosure address the shortcomings of existing methods and structures in more detail below, in general, various embodiments of this disclosure provide improved methods for forming SiCN and / or SiOCN (also referred to herein as SiCON) layers with desired properties (e.g., desired etch resistance, desired dielectric constant, desired composition, desired density, etc.). Alternatively or additionally, exemplary methods provide relatively efficient processes for forming structures including both SiCN and SiOCN layers.

[0009] According to at least one embodiment of this disclosure, a method of forming a structure including a silicon carbonitride layer includes: providing a substrate in a reaction chamber; providing a silicon precursor in the reaction chamber; providing a nitrogen-containing reactant in the reaction chamber; and forming a plasma in the reaction chamber while providing one or more of the silicon precursor and the nitrogen-containing reactant. Forming the plasma may include providing plasma power to electrodes within the reaction chamber. According to examples of this disclosure, the frequency of the plasma power is equal to or greater than 60 MHz. A plasma power frequency equal to or greater than 60 MHz allows the formation of a structure with desired properties (e.g., greater than 2.3 g / cm³). 3 The method comprises a silicon carbonitride layer with a density and a dielectric constant of less than 5 or 4.5. According to various examples of these embodiments, the silicon precursor includes one or more of aminosilanes or alkylsilanes. According to further examples, the nitrogen-containing reactant includes one or more of nitrogen, ammonia (NH3), hydrazine (N2H4), triazine (N3H5), alkyl-substituted hydrazine, triazine, or C1-C4 amine. The method may also include the step of forming a silicon oxynitride layer on the silicon carbonitride layer.

[0010] According to further embodiments of this disclosure, a continuous method is provided for forming a structure comprising a silicon carbonitride layer and a silicon oxynitride layer. The continuous method can be used to form the silicon carbonitride layer and the silicon oxynitride layer in an efficient and time-saving manner. According to various embodiments, the continuous method includes providing a substrate in a reaction chamber, providing a silicon precursor in the reaction chamber, providing a first nitrogen-containing reactant in the reaction chamber, providing a second nitrogen-containing reactant in the reaction chamber, and forming a plasma by providing plasma power in the reaction chamber while providing one or more of the silicon precursor and the first nitrogen-containing reactant to form the silicon carbonitride layer. Exemplary methods also include reducing the flow rate of the second nitrogen-containing reactant and providing or increasing the flow rate of an oxygen-containing reactant during a transition period while maintaining the plasma, and forming the silicon oxynitride layer while continuing to maintain the plasma. According to various examples of these embodiments, the frequency of the plasma power is equal to or greater than 60 MHz. In some cases, the plasma forming step includes providing dual-frequency plasma power, wherein at least one frequency of the dual-frequency plasma power is equal to or greater than 60 MHz. According to another example, during the transition period, the flow rate of the second nitrogen-containing reactant is reduced by about 40% or more. According to another example, the oxygen-containing reactant comprises carbon. In some cases, oxygen-containing reactants include mixtures containing hydrogen-containing gases.

[0011] According to another exemplary embodiment of this disclosure, a structure includes a layer comprising SiCN and / or SiOCN. The structure can be formed using, for example, the methods described herein.

[0012] According to another embodiment, a reactor system is provided. An exemplary reactor system includes a reaction chamber, a precursor source coupled to the reaction chamber, one or more reactant sources, and a controller. The controller may be configured to perform the methods described herein. The reactor system may include multiple reaction chambers. One or more steps performed by the controller may be performed in one or more of the multiple reaction chambers.

[0013] These and other embodiments will become apparent to those skilled in the art from the following detailed description of certain embodiments with reference to the accompanying drawings; the invention is not limited to any particular embodiment disclosed. Attached Figure Description

[0014] Exemplary embodiments of this disclosure can be more fully understood when considered in conjunction with the following illustrative drawings, and by referring to the detailed description and claims.

[0015] Figure 1 A method for forming a structure comprising a silicon carbonitride layer according to at least one embodiment of the present disclosure is shown.

[0016] Figure 2 Another method for forming a structure comprising a silicon carbonitride layer according to at least one embodiment of the present disclosure is shown.

[0017] Figure 3 Timings according to at least one embodiment of the present disclosure are shown.

[0018] Figure 4 The structure according to at least one embodiment of the present disclosure is shown.

[0019] Figure 5 A schematic diagram of a reactor system according to an example of this disclosure is shown.

[0020] Figure 6 A schematic diagram of a reactor system with multiple reaction chambers according to an example of this disclosure is shown.

[0021] Figure 7 The dielectric constant of a silicon carbonitride layer according to an example of this disclosure is shown in relation to film density, leakage, and stress.

[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 embodiments shown in 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 embodiments and / or uses disclosed herein, as well as their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited to the specific embodiments described below.

[0024] This disclosure generally relates to methods for forming structures including silicon carbonitride layers. As described in more detail below, the methods described herein can be used to form silicon carbonitride layers with desired properties, such as relatively high density, relatively high resistance to wet etch, relatively low dielectric constant, relatively low leakage current to an applied field, and / or with desired composition, such as desired carbon concentration.

[0025] The exemplary methods described herein can be used to form structures suitable for a variety of applications, such as forming electronic devices. For example, the method can be used to form structures suitable for cell isolation, self-aligned vias, dummy gates, inverted tone patterns, PC RAM isolation, cut hard masks, DRAM memory node contact (SNC) isolation, etc., in 3D cross-point memory devices.

[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 are formed. A substrate may comprise a bulk material, such as silicon (e.g., single-crystal silicon), other group IV materials (e.g., germanium), or compound semiconductor materials (e.g., group III-V or group II-VI semiconductors), and may comprise one or more layers overlying or underlying the bulk material. Furthermore, a substrate may include various features such as gaps (e.g., recesses or vias), lines, or protrusions, such as lines having gaps formed therebetween, formed on or within at least a portion of the layers or bulk material of the substrate.

[0027] In some embodiments, a membrane refers to a layer extending in a direction perpendicular to the thickness direction. In some embodiments, a layer refers to a material of a certain thickness formed on a surface, and may be synonymous with 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 be established based on or not 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] In this disclosure, "continuous" or "serial" can refer to a step that does not break the vacuum, is uninterrupted in timeline, involves no material intervention, does not change processing conditions, follows immediately after, is the next step, or, in some embodiments and depending on the circumstances, is a discrete physical or chemical structure that, apart from the two structures, has no intervention between them.

[0029] As used herein, a silicon carbonitride layer or a layer comprising SiCN includes a material having silicon, carbon, and nitrogen. In some embodiments, the SiCN layer may include one or more elements other than Si, C, and N, such as H and / or O. In some embodiments, the SiCN layer may contain about 1.5% to about 50% carbon on an atomic basis. In some embodiments, the SiCN layer may contain about 3.0% to about 40% carbon on an atomic basis. In some embodiments, the SiCN layer may contain about 0% to about 6.0% oxygen on an atomic basis. In some embodiments, the SiCN layer may contain substantially no oxygen on an atomic basis. In some embodiments, the SiCN layer may contain about 25% to about 50% silicon on an atomic basis. In some embodiments, the SiCN layer may contain about 30% to about 50% silicon on an atomic basis. In some embodiments, the SiCN layer may contain about 1.5% to about 40% hydrogen on an atomic basis. In some other embodiments, the SiCN layer may contain about 0% to about 50% on an atomic basis (atomic %).

[0030] As used herein, unless otherwise stated, the silicon oxynitride (SiOCN) layer is not intended to limit, constrain, or define the bonding or chemical state, such as oxidation state, of any of the Si, O, C, N, and / or any other elements in the film. Furthermore, in some embodiments, the SiOCN layer may contain one or more elements other than Si, O, C, and N, such as H. In some embodiments, the SiOCN layer may contain Si-C bonds and / or Si-O bonds. In some embodiments, the SiOCN layer may contain more Si-O bonds than Si-C bonds; for example, the ratio of Si-O bonds to Si-C bonds may be from about 1:1 to about 10:1. In some embodiments, the SiOCN layer may contain about or greater than 0% to about 40% carbon on an atomic basis. In some embodiments, the SiOCN layer may contain about 0.1% to about 40% carbon on an atomic basis. In some embodiments, the SiOCN layer may contain about or greater than 0% to about 70% oxygen on an atomic basis. In some embodiments, the SiOCN layer may contain about 10% to about 70% oxygen on an atomic basis. In some embodiments, the SiOCN layer may comprise about 20% to about 55% silicon on an atomic basis. In some embodiments, the SiOCN layer may comprise about 10% to about 50% silicon on an atomic basis. In some embodiments, the SiOCN layer may comprise about 3.0% to about 40% hydrogen on an atomic basis. In some other embodiments, the SiOCN layer may comprise about 0% to about 20% nitrogen on an atomic basis (atomic %).

[0031] The dielectric constant of the SiCN layer can range from about 3 to about 5.5 or from about 3.6 to less than 5 or less than 4.5. Alternatively, the density of the SiCN layer can be greater than 2.3 g / cm³. 3 Additional properties of SiCN and SiOCN layers according to this disclosure are provided below.

[0032] In this disclosure, any two numbers of a variable may constitute a feasible range of the variable, and any indicated range may include or exclude endpoints. Furthermore, any value of the indicated variable (whether or not it is indicated by an approximation) may refer to an exact value or an approximate value and include equivalents, and in some embodiments may refer to an average, median, representative value, multi-value, etc. Additionally, in this disclosure, the terms "comprising," "consisting of," and "having" may, in some embodiments, independently mean generally or broadly comprising, including, substantially consisting of, or composed of. The meaning of any definition in this disclosure does not necessarily exclude the common and customary meanings in some embodiments.

[0033] Now turn to the attached image. Figure 1A method 100 according to an example of this disclosure is illustrated. Method 100 includes providing a substrate in a reaction chamber (step 102), providing a silicon precursor in the reaction chamber (step 104), providing a nitrogen-containing reactant in the reaction chamber (step 106), and forming a plasma in the reaction chamber while providing one or more of the silicon precursor and the nitrogen-containing reactant (step 108). Although shown separately, one or more (e.g., all) of steps 104-108 may overlap in time. For example, steps 104-108 may overlap in time to perform a plasma-enhanced chemical vapor deposition (PECVD) process, as shown in 110.

[0034] The substrate provided during step 102 can be provided in any suitable reaction chamber of any suitable reactor. According to examples of this disclosure, the reaction chamber can be part of a chemical vapor deposition (CVD) reactor (such as a PECVD reactor). The reactor can be a single-substrate reactor or a batch reactor. The reactor including the reaction chamber can be equipped with a heater to activate the reaction by raising the temperature of one or more of the substrate and / or reactants and / or precursors. Exemplary reactors and reactor systems suitable for method 100 are described in more detail below.

[0035] After step 102 and during or before steps 102-108, the substrate may be brought to the desired temperature and pressure for forming the silicon carbonitride layer. For example, the temperature within the reaction chamber (e.g., the temperature of the substrate or substrate support) may be between about 75°C and about 500°C. The pressure within the reaction chamber during one or more of steps 104-108 may be between about 250 Pa and about 900 Pa.

[0036] During step 104, a silicon precursor is provided in the reaction chamber. The silicon precursor may be, or may include, for example, an aminosilane or an alkylsilane.

[0037] In some embodiments, the silicon precursor may be represented by the following formula.

[0038]

[0039] In this embodiment, at least one R1-R4 group is independently selected from amino or C1-C4 alkyl, and the other R1-R4 groups may be independently selected from amino, C1-C4 alkyl, or H. Exemplary amino groups include C1-C4 alkylamines.

[0040] In some cases, a silicon precursor may include two silicon atoms. In such cases, the silicon atoms may be bonded together or individually to one or more other atoms.

[0041] As a specific example, the silicon precursor may be or include one or more of the following: (SiH3)2NMe, (SiH3)2NEt, (SiH3)2N(iPr), (SiH3)2N(tBu), SiH3NEt2, SiH3N(tBu)2, SiH2(NEt2)2, SiH2(NMe2)2, SiH2(NHtBu)2, SiH2(NHSiMe3)2, SiH3N(iPr)2, SiH(N(Me)2)3, SiH2[N(Et)(Me)]2, Si2(NHEt)6, Si(NHEt)4, Si(CH3)4, (CH3)3SiH, or mixtures thereof. In this document, for the corresponding groups, Me refers to methyl, Et refers to ethyl, Bu refers to butyl, t refers to tert-butyl, and Pr refers to propyl.

[0042] A carrier gas can be used to supply the silicon precursor to the reaction chamber. Exemplary suitable carrier gases include one or more of Ar, He, and N2. The flow rate of the carrier gas used to supply the silicon precursor to the reaction chamber can be between about 100 and about 5000 sccm or between about 2000 and about 4000 sccm.

[0043] During step 106, nitrogen-containing reactants are provided in the reaction chamber. As described above, step 106 may overlap with step 104.

[0044] According to various examples, the nitrogen-containing reactants do not include oxygen. According to a particular example, the nitrogen-containing reactants include nitrogen and hydrogen. Exemplary nitrogen-containing reactants suitable for step 106 include one or more of nitrogen (N2), ammonia (NH3), hydrazine (N2H4), triazine (N3H5), (e.g., C1-C4) alkyl-substituted hydrazine, triazine, or C1-C4 amine. According to a more particular example, the nitrogen-containing reactants comprise one or more of N2, NH3, NH4, N2H2, N2H4, or mixtures thereof. The flow rate of the nitrogen-containing reactants to the reaction chamber can be between about 75 and about 2500 sccm.

[0045] During step 108, a plasma is formed in the reaction chamber while one or more of a silicon precursor and a nitrogen-containing reactant are provided by supplying plasma power to the electrodes within the reaction chamber. According to examples of this disclosure, the frequency of the plasma power is equal to or greater than 60 MHz, or between about 60 MHz and about 100 MHz. The power intensity used to form the plasma can be between about 200 and about 1200 W.

[0046] Using plasma power at frequencies equal to or greater than 60 MHz expands the range of process parameters available for adjusting the quality (e.g., density, dielectric constant, etc.) of the deposited silicon carbonitride layer. For example, using power at frequencies of 60 MHz or higher can produce silicon carbonitride layers with relatively low dielectric constants while maintaining the desired film density. Table 1 below illustrates various properties of silicon carbonitride layers formed using plasma power at frequencies of 60 MHz or higher versus plasma power at lower frequencies (e.g., less than 20 MHz). Figure 7 The dielectric constant, film density, leakage, and stress of silicon carbonitride layers deposited using 60 MHz (data 702) and 13.56 MHz (data 704) under the same or similar conditions are shown. As illustrated, using power at 60 MHz or higher frequencies reduces the dielectric constant in the layer and can reduce stress while maintaining the desired density, compared to lower frequencies (e.g., 20 MHz or 15 MHz or lower).

[0047] Table 1

[0048]

[0049] Although not shown separately, according to various examples of this disclosure, method 100 may also include the step of forming a silicon oxynitride layer on the silicon carbonitride layer. The step of forming the silicon oxynitride layer may be combined with the following... Figure 2 As stated above.

[0050] Figure 2 Another method 200 is shown. Method 200 is a continuous method for forming a structure comprising a silicon carbonitride layer and a silicon oxynitride layer. Typically, such layers are formed using separate or discontinuous processes, wherein a first plasma is formed to form a first layer, and another plasma is formed to form a second layer. In contrast, method 100 employs a continuous plasma to form both the silicon carbonitride layer and the silicon oxynitride layer.

[0051] As shown in the figure, method 200 includes the following steps: providing a substrate (202) in a reaction chamber, providing a silicon precursor (204) in a reaction chamber, providing a first nitrogen-containing reactant (206) in a reaction chamber, providing a second nitrogen-containing reactant (208) in a reaction chamber, forming a plasma by providing plasma power in the reaction chamber, while providing one or more of the silicon precursor and the first nitrogen-containing reactant to form a silicon carbonitride layer (210), reducing the flow rate of the second nitrogen-containing reactant (214) and providing or increasing the flow rate of an oxygen-containing reactant (216) during a transition period (218) while maintaining the plasma, and forming a silicon oxynitride layer (220) while continuing to maintain the plasma.

[0052] Steps 202 and 204 can be the same as or similar to steps 102 and 104 described above. For example, the reaction chamber temperature and / or pressure, as well as the silicon precursor, can be as described above in conjunction with steps 102 and 104.

[0053] Steps 206 and / or 208 may be the same as or similar to step 106 described above. For example, the first and / or second nitrogen-containing reactants may be or include any of the nitrogen-containing reactants described above. In some cases, the first and second nitrogen-containing reactants may be different. As a specific example, the first nitrogen-containing reactant may be or include one or more of NH3 or N2. Alternatively or additionally, the second nitrogen-containing reactant may contain one or more of N2, NH3, or C1-C4 (e.g., alkyl)amines. The flow rates of the first and / or second nitrogen-containing reactants may be as described above in conjunction with step 106.

[0054] During step 210, a plasma is formed in the reaction chamber while one or more of the silicon precursor and nitrogen-containing reactant are provided by supplying plasma power to the electrodes within the reaction chamber. According to examples of this disclosure, the frequency of the plasma power is equal to or greater than 60 MHz or is between about 60 MHz and about 100 MHz. The power intensity used to form the plasma can be between about 200 and about 1200 W. According to some examples of this disclosure, the plasma formation step includes providing dual-frequency plasma power, wherein at least one frequency of the dual-frequency plasma power is equal to or greater than 60 MHz. The other frequency can be in the range, for example, between about 60 MHz and about 100 MHz.

[0055] Steps 204-210 may overlap, such that a silicon carbonitride layer is formed at least partially using a PECVD process 212 including steps 204-210. After forming a silicon carbonitride layer for a specified duration or desired thickness (e.g., about 1 to about 20 nm), method 200 proceeds to a transition step 218, which in the illustrated example includes stopping or reducing the flow rate 214 of the second nitrogen-containing reactant and increasing the flow rate of the oxygen-containing reactant or providing oxygen-containing reactant 216 while maintaining the plasma.

[0056] According to an example of this disclosure, during transition period 218, the flow rate of the second nitrogen-containing reactant may be reduced by about 85% or more. According to another example, the flow rate of the second nitrogen-containing reactant may be reduced by 3000 sccm or more.

[0057] The oxygen-containing reactant provided during step 218 may be or includes an oxygen-containing gas. In some cases, the oxygen-containing reactant contains carbon. In some cases, the oxygen-containing reactant includes a mixture containing a hydrogen-containing gas. As a specific example, the oxygen-containing reactant or gas may be or includes CO2. Alternatively or alternatively, the hydrogen-containing gas may be or includes H2 or NH4.

[0058] The duration of transition step 218 can be between approximately 2.0 seconds and approximately 6.0 seconds. During this step, one or more of the flow rates of the second nitrogen-containing reactant and / or the oxygen-containing reactant are reduced.

[0059] Figure 3 A timing sequence 300 suitable for use with method 200 is shown. As shown, timing sequence 300 includes a silicon carbonitride layer formation step 212, a transition step 218, and a silicon carbonitride oxynitride layer formation step 220. Figure 3 As further shown, the steps of providing the silicon precursor 302, providing the first nitrogen-containing reactant 304, and providing plasma power (e.g., high-frequency and low-frequency plasma power) 310 are continuous throughout the timing sequence 300 (e.g., remaining substantially constant or substantially the same). As described above, the step of providing the second nitrogen-containing reactant 308 may be reduced during transition step 218 and may thereafter continue during step 220 (e.g., remaining substantially constant). The step of providing the oxygen-containing reactant 306 may be increased during transition step 218 and may thereafter continue during step 220 (e.g., remaining substantially constant).

[0060] Figure 4 A structure 400 formed using method 200 is shown. The structure 400 includes a substrate 402, a silicon carbonitride layer 404 (e.g., directly) formed on the substrate 402, and a silicon oxynitride layer 406 (e.g., directly) formed on the silicon carbonitride layer 404.

[0061] Figure 5 The present invention illustrates a reactor system 500 according to an exemplary embodiment of the present disclosure. The reactor system 500 may 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.

[0062] The reactor system 500 includes a pair of parallel, facing conductive plate electrodes 514, 518 within the interior 501 (reaction zone) of the reaction chamber 502. Plasma can be excited within the reaction chamber 502 by applying plasma power, for example, from a plasma power source 508, to one electrode (e.g., electrode 514) and electrically grounding the other electrode (e.g., electrode 518). The power source 508 can be coupled to electrode 514 via transmission line 529 and RF filter 531. A temperature regulator 503 can be disposed in the lower platform 514 (lower electrode), and the temperature of the substrate 522 placed thereon can be maintained at a desired temperature, such as the temperature described above. Electrode 518 can serve as a gas distribution device, such as a spray plate or spray head. Precursor gas, reactant gas, and carrier gas or inert gas (if any) can be introduced into the reaction chamber 502 using one or more gas lines (e.g., reactant gas line 504 and precursor gas line 506, respectively connected to reactant and precursor sources). For example, inert gas and reactants (e.g., as described above) can be introduced into reaction chamber 502 using line 504 and / or precursor, and carrier gas (e.g., inert gas as described above) can be introduced into reaction chamber 502 using line 506. Although two inlet gas lines 504, 506 are shown, reactor system 500 may include any suitable number of gas lines.

[0063] In reaction chamber 502, a circular pipe 520 with an exhaust line 521 can be formed within a metal pipe plate 530, through which gas in the interior 501 of reaction chamber 502 can be discharged to exhaust source 510. Additionally, transfer chamber 523 can be provided with a sealing gas line 532 to introduce sealing gas into the interior 501 of reaction chamber 502 via the interior of transfer chamber 523 (transfer zone). A separation plate 525 (omitted in this figure, through which the substrate is transferred in and out of transfer chamber 523) can be provided for separating reaction zone 501 and transfer chamber 523. Transfer chamber 523 may also be provided with an exhaust line 527 connected to exhaust source 510. In some embodiments, a flow-through system (FPS) can be used to achieve continuous flow of carrier gas to reaction chamber 502.

[0064] Reactor system 500 may include one or more controllers 512, which are programmed or otherwise configured to cause one or more method steps as described herein to be performed. As those skilled in the art will understand, controller 512 is connected to various power sources, heating systems, pumps, robots, and gas flow controllers or reactor valves. For example, controller 512 may be configured to control the gas flow of precursors, reactants, and inert gases into at least one of one or more reaction chambers to form a layer on the surface of a substrate. Controller 512 may be further configured to provide power to, for example, form a plasma within reaction chamber 502. Controller 512 may similarly be configured to perform additional or alternative steps as described herein. For example, controller 512 may be configured to perform a sequential method as described above for forming a structure comprising a silicon carbonitride layer and a silicon carbon oxynitride layer.

[0065] Controller 512 may include electronic circuitry and software to selectively operate valves, manifolds, heaters, pumps, and other components included in system 500. Such circuitry and components operate to introduce precursors, reactants, and purge gases from appropriate sources. Controller 512 may control the timing of gas pulse sequences, the temperature of the substrate and / or reaction chamber, the pressure within the reaction chamber, and various other operations to provide appropriate operation of system 500.

[0066] Controller 512 may include control software to electrically or pneumatically control valves to control the inflow and outflow of precursors, reactants, and / or purge gases from reaction chamber 502. Controller 512 may include modules, such as software or hardware components, like FPGAs or ASICs, that perform certain tasks. Modules may be advantageously configured to reside on addressable storage media of the control system and configured to perform one or more processes.

[0067] 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 reactant gases and rare gases may be supplied via a common line, while precursor gases may be supplied via a non-common line.

[0068] During operation of system 500, a substrate, such as a semiconductor wafer, is transferred from, for example, substrate transport region 523 to reaction region 501. Once the substrate is transferred to reaction region 501, one or more gases (e.g., precursors, reactants, carrier gases, and / or purge gases) are introduced into reaction chamber 502.

[0069] Figure 6 A reactor system 600 is shown comprising multiple reaction chambers 602-608, each reaction chamber being... Figure 5An example of reaction chamber 502 is provided. Reaction chambers 602-608 may be disposed around and / or coupled to transfer chamber 610, which includes transfer tools 612 for transferring a substrate between reaction chambers 602-608 and load locking chamber 614, and between reaction chambers 602-608 (e.g., through transfer chamber 610). For example, substrate 530 may be disposed in different chambers for different steps of the method described herein.

[0070] The exemplary embodiments described above do not limit the scope of the invention, as these embodiments are merely examples of embodiments of the invention, the scope of which is defined by the appended claims and their legal equivalents. Any equivalent embodiments are intended to fall within the scope of the invention. In fact, various modifications to this disclosure, such as alternative useful combinations of the described elements, in addition to those shown and described herein, will become apparent to those skilled in the art from the description. These modifications and embodiments are also intended to fall within the scope of the appended claims.

Claims

1. A method for forming a structure including a silicon carbonitride layer, the method comprising: A substrate is provided within the reaction chamber; Silicon precursors are provided within the reaction chamber; Nitrogen-containing reactants are provided in the reaction chamber; as well as Plasma is formed in the reaction chamber while providing one or more of silicon precursors and nitrogen-containing reactants. Plasma formation includes supplying plasma power to the electrodes within the reaction chamber, and The frequency of the plasma power is equal to or greater than 60MHz.

2. The method according to claim 1, wherein, The silicon precursor includes one or more of aminosilanes or alkylsilanes.

3. The method according to claim 2, wherein, The silicon precursor includes one or more of the following: (SiH3)2NMe, (SiH3)2NEt, (SiH3)2N(iPr), (SiH3)2N(tBu), SiH3NEt2, SiH3N(tBu)2, SiH2(NEt2)2, SiH2(NMe2)2, SiH2(NHtBu)2, SiH2(NHSiMe3)2, SiH3N(iPr)2, SiH(N(Me)2)3, SiH2[N(Et)(Me)]2, Si2(NHEt)6, Si(NHEt)4, Si(CH3)4, (CH3)3SiH, or mixtures thereof.

4. The method according to claim 1, wherein, The nitrogen-containing reactants include one or more of nitrogen, ammonia (NH3), hydrazine (N2H4), triazine (N3H5), alkyl-substituted hydrazine, triazine, or C1-C4 amine.

5. The method according to claim 1, wherein, The nitrogen-containing reactants include one or more of N2, NH3, NH4, N2H2, N2H4, or mixtures thereof.

6. The method according to claim 1, wherein, The density of the silicon carbonitride layer is greater than 2.3 g / cm³. 3 .

7. The method according to claim 6, wherein, The dielectric constant of the silicon carbonitride layer is less than 5.

8. The method according to claim 1, further comprising the step of forming a silicon oxynitride layer on the silicon carbonitride layer.

9. A continuous method for forming a structure comprising a silicon carbonitride layer and a silicon carbon oxynitride layer, the method comprising the following steps: A substrate is provided within the reaction chamber; Silicon precursors are provided within the reaction chamber; The first nitrogen-containing reactant is provided in the reaction chamber; A second nitrogen-containing reactant is provided in the reaction chamber; A silicon carbonitride layer is formed by providing plasma power in a reaction chamber while providing one or more of a silicon precursor and a first nitrogen-containing reactant. While maintaining plasma, the flow rate of the second nitrogen-containing reactant is reduced during the transition period, and an oxygen-containing reactant is provided; and While maintaining the plasma, a carbon silicon oxide layer is formed.

10. The method according to claim 9, wherein, The frequency of the plasma power is equal to or greater than 60 MHz.

11. The method according to claim 9, wherein, The steps of forming plasma include providing dual-frequency plasma power, wherein at least one frequency of the dual-frequency plasma power is equal to or greater than 60 MHz.

12. The method according to claim 9, wherein, The silicon precursor includes one or more of aminosilanes or alkylsilanes.

13. The method according to claim 9, wherein, The silicon precursor includes one or more of the following: (SiH3)2NMe, (SiH3)2Net, (SiH3)2N(iPr), (SiH3)2N(tBu), SiH3NEt2, SiH3N(tBu)2, SiH2(NEt2)2, SiH2(NMe2)2, SiH2(NHtBu)2, SiH2(NHSiMe3)2, SiH3N(iPr)2, SiH(N(Me)2)3, SiH2[N(Et)(Me)]2, Si2(NHEt)6, Si(NHEt)4, Si(CH3)4, (CH3)3SiH, or mixtures thereof.

14. The method according to claim 9, wherein, The first nitrogen-containing reactant includes one or more of N2, ammonia (NH3), hydrazine (N2H4), triazine (N3H5), C1-C4 alkyl-substituted hydrazine, triazine, or C1-C4 amine.

15. The method according to claim 9, wherein, The first nitrogen-containing reactant includes one or more of NH3 or N2.

16. The method according to claim 9, wherein, The second nitrogen-containing reactant includes one or more of N2, NH3, or C1-C4 amines.

17. The method according to claim 9, wherein, The flow rate of the second nitrogen-containing reactant decreases by approximately 40% or more during the transition period.

18. The method according to claim 9, wherein, The oxygen-containing reactants include carbon.

19. The method according to claim 9, wherein, The oxygen-containing reactants include a mixture containing hydrogen-containing gas.

20. The method according to claim 19, wherein, The hydrogen-containing gas includes one or more of H2 or NH4.

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