Systems and methods for preparing trisilylamine

Abstract

The present invention discloses a system and method for gas phase synthesis of trisilylamine. A system includes a reaction vessel having a top, a bottom and a sidewall having an inner surface. The reaction vessel includes an inlet for gaseous reactants and a gas inlet for an inert gas. In some reactors, the gas inlet is positioned near the top of the reaction vessel and is configured to inject the reaction gas into the reactor substantially vertically and downwardly therefrom. Other reactors are cyclone-shaped with tangential feed gas. One or more guide plates have a peripheral edge and are positioned substantially horizontally in the reactor to define a reaction zone above the guide plate and a separation zone below the guide plate. The guide plate is positioned in the reaction vessel so that there is a gap between the peripheral edge of the guide plate and the inner surface of the reaction vessel. Some systems and methods include a mechanical or static mixer.

Description

Background Art Technical Field

[0002] The present disclosure relates to methods and systems for preparing trisilylamine. Specifically, the present disclosure relates to methods and systems featuring one or more baffles or other separation devices, and in certain embodiments, one or more turbulence inducing features within a reactor for preparing trisilylamine. Background Art

[0003] Trisilylamine is an important precursor for semiconductor manufacturing. It is widely used to make silicon dielectric films into high aspect ratio (HAR) structures, such as shallow trench isolation (STI) in FinFET transistor processes and memory channel holes (or Macaroni bit lines) in 3D NAND flash memory processes. Under remote plasma excitation with other co-reactant gases, trisilylamine polymerizes and generates a flowable liquid-like reaction intermediate on the surface of the substrate. Flow chemical vapor deposition (FCVD) can be used in challenging HAR air gap filling applications, which overcomes the partial filling or void problems of conventional high-density plasma CVD gap filling using TEOS or other silicon precursors. The ability to form a flowable liquid mediated by trisilylamine and its co-reactants is a key advantage of HAR air gap filling. After the liquid intermediate flows into the HAR gap or hole, the filled intermediate continues to grow and solidify into a carbon-free and halogen-free Si:N:O:H-containing polymer. Typical co-reactants are oxidants, such as nitrous oxide N2O. Subsequent steam (H2O) and / or O3 annealing steps convert the polymer into high quality and high purity silicon dioxide SiO2, which is the best electrical insulating film for device insulation because it does not contain carbon or halogen atoms.

[0004] Trisilylamine (TSA) can be prepared from silyl halides and ammonia. Initial tests by Stock and Somieski (1921) in the reaction of monochlorosilane (MCS) with ammonia (NH3) found an instantaneous reaction with precipitation of a solid white substance. However, they could not determine whether monosilylamine (MSA, SiH3(NH2)) or disilylamine (DSA, (SiH3)2NH) or trisilylamine (TSA, (SiH3)3N) had been formed. The general mechanism for the formation of TSA is thought to be the stepwise addition of silyl chloride and ammonia by the following scheme:

[0005] SiH3Cl+2NH3→SiH3NH2+NH4Cl (1)

[0006] SiH3NH2+SiH3Cl+NH3→(SiH3)2NH+NH4Cl (2)

[0007] (SiH3)2NH+SiH3Cl+NH3→(SiH3)3N+NH4Cl (3)

[0008] And the overall reaction scheme is:

[0009] 3SiH3Cl+4NH3→(SiH3)3N+3NH4Cl (4)

[0010] Stock and Somieski (1921) also reported that the reaction of excess ammonia with MCS resulted in the formation of TSA, silanes, and nonvolatile polysilazanes. They proposed two decomposition modes for DSA; one is hydrogen migration:

[0011] x(SiH3)2NH→(SiH2NH) x +xSiH4 (5)

[0012] Another involves Si-N disproportionation:

[0013] 3(SiH3)2NH→2(SiH3)3N+NH3 (6)

[0014] Burg and Kuljiais (1950) reported high yields of TSA when the gaseous ammonia was introduced slowly (non-turbulently) into the gaseous MCS. To obtain good yields, they reported that the chlorosilanes had to be pure and the gaseous ammonia had to be introduced slowly into the gaseous MCS from below. The best yields of TSA accounted for 80% of the ammonia used.

[0015] Wells and Schaeffer (1966) discussed a batch process for the preparation of TSA by the reaction of silyl chloride with ammonia. They reported that the yield of TSA varied depending on the mixing method and the purity of the reactants. They mixed the reactants in the gas phase by introducing ammonia from below into a 1 liter bulb filled with silyl chloride. After very slowly introducing the gaseous ammonia, the reaction bulb and contents were held at room temperature for 15 minutes. As soon as mixing occurred, a large amount of white solid precipitated on the walls of the bulb. The product was removed and trisilylamine was recovered. The process yield was about 77% of the theoretical amount of trisilylamine. They also studied the reaction of bases with TSA and found that the reaction occurred in the liquid phase. Silanes are always formed in these reactions, and under certain conditions, N,N',N"-trimethylsilylcyclotrisilazane can be prepared according to the following scheme:

[0016] xNH3+3(SiH3)3N→3SiH4+(SiH3NSiH2)3+xNH3 (7)

[0017] The reaction mechanism for the synthesis of TSA has been extensively studied. In particular, the key intermediate monosilylamine (MSA) was not successfully detected, leading Aylett (1968) to question reaction (1). However, the existence of DSA was confirmed. Aylett and Hakim (1966) reported the preparation of DSA from diphenylaminosilane and ammonia at low temperatures. They determined that reaction (6) did not occur in the gas phase, but that the disproportionation reaction occurred slowly in the liquid phase at 0°C. They also observed that the reaction of DSA with silyl iodide did not occur rapidly (if at all) in the gas phase, but that the reaction was rapid and nearly quantitative in the condensed phase to give 87% TSA:

[0018] 4(SiH3)2NH+SiH3I→3(SiH3)3N+NH4I (8)

[0019] Recently, in situ mass spectrometric studies of silane / ammonia chemical vapor deposition (CVD) processes have led to the detection of MSA. MSA was first observed by Wu (1987) in mercury-sensitive photochemical studies of silane / ammonia mixtures. Wu reported that MSA decomposed in the dark and had a half-life of 1 hour to 20 hours, depending on the surface preparation of the gas cell. MSA was also observed in Smith et al. (1988) in studies of silane / ammonia plasma-enhanced CVD using a triple quadrupole mass spectrometer.

[0020] Beach (1992) studied the reaction of silyl iodide with ammonia under slow flow conditions using FTIR spectroscopy and mass spectrometry. At low (0.01 mbar) partial pressures of silyl iodide in excess ammonia, MSA was the only silylamine observed. At 0.1 mbar silyl iodide pressure, significant amounts (about 10%) of DSA were observed, indicating that both MSA and DSA intermediates were produced in the gas phase. No TSA was observed in the gas phase reaction of silyl iodide with ammonia under the low pressure conditions studied. This study confirmed that MSA is a reaction product formed by the gas phase reaction of ammonia and silyl iodide. Second, even in the gas phase, the MSA formed is sufficiently basic to react rapidly with a second molecule of silyl iodide to form DSA. This is in contrast to the reactivity of DSA with silyl iodide, which does not react in the gas phase, but only in the condensed phase, according to reaction (8). MSA does not disproportionate rapidly even in the presence of excess ammonia, which is consistent with the observations of Wu (1987), who observed only a slow disproportionation reaction that may have occurred on the reactor wall. DSA also does not disproportionate in the gas phase. Ultimately, MSA and DSA do not react rapidly to form trisilylamine. These observations suggest that the major pathway for the synthesis of TSA from halosilanes and ammonia is the stepwise silylation of ammonia to MSA, DSA, and finally to TSA.

[0021] The above-mentioned study on the mechanism of synthesizing TSA is crucial to understanding the shortcomings of existing methods. Various methods for the industrial-scale synthesis of TSA have been developed, but each method has one or more shortcomings. Various efforts in this field can be illustrated by the following patents: U.S. Patents 8,409,513B2, 8,568,682B2 and 9,284,198B2. U.S. Patent 8,409,513 describes a tubular flow gas phase reactor and a batch method for synthesizing silylamines. The reactor has a combination of characteristics present in plug flow and laminar flow devices, and is said to result in high-volume and efficient synthesis of silylamines. However, the method produces a large amount of ammonium halide solids deposited on the tube wall and the feed nozzle, which not only blocks the reaction tube, but also limits the available production capacity. Therefore, after producing each production batch, the reaction tube needs to be opened and cleaned. Cleaning is a labor-intensive process that causes significant downtime. In order to minimize the deposition on the reactor wall, non-stick materials such as fluoropolymers are used. Although the diameter of the tubular reactor can be increased to increase the available capacity, as the diameter of the tube increases, mixing and therefore the reaction efficiency deteriorates. In addition, the process also results in a large amount of DSA together with TSA, which will require subsequent conversion to TSA. In the example shown, the conversion of DSA to TSA is carried out in a relatively short time during the warming period of the collected product liquid with an excess of silyl halide. However, the conversion results in solid ammonium chloride (AMC) in the TSA / DSA mixture, which requires an additional separation step. The separated AMC still contains part of TSA / DSA, so a special waste treatment process is required. Additional separation steps are also required to separate and recycle excess silyl halide to reduce costs.

[0022] U.S. Patent 8,568,682B2 describes a condensed phase batch process for synthesizing TSA. The present invention describes an improved synthesis method, which includes a solvent to help promote the condensation phase reaction between ammonia (or liquid) and liquefied MCS with good yields. The solvents used include anisole, toluene and xylene. It is said that this method is conducive to removing by-product waste, and there is almost no reactor downtime, significantly reducing downstream solid pollution, and a high-purity product can be obtained in the first distillation. The optimal TSA yield is about 94%. It is estimated that about 6% of the collected crude product is carried into the solvent, salts and heavy objects. The crude product contains TSA and DSA in a ratio of 2: 1, plus silane and excess MCS. Therefore, additional steps are required to separate and recycle excess MCS and convert DSA into TSA.

[0023] U.S. Patent 9,284,198 B2 describes a method for preparing trisilylamine with the purpose of forming very little DSA. A reaction mixture of trisilylamine and monochlorosilane is fed into a reactor, wherein the reaction mixture is at a temperature and pressure sufficient to provide trisilylamine in the liquid phase without the addition of any solvent. Ammonia is sprayed through the reaction mixture to provide a crude mixture comprising trisilylamine and ammonium chloride solids, wherein monochlorosilane is in stoichiometric excess relative to ammonia. TSA is produced at a purity level of 90% or more, wherein less than 1% DSA is formed. The process yield is 80% or greater. The method also limits the formation of solid ammonium chloride to a single reactor for ease of cleaning. However, the method has the disadvantages of recycling excess MCS and separating ammonium chloride from the liquid product.

[0024] All liquid phase processes for preparing TSA suffer from the fact that ammonium chloride actually catalyzes the decomposition of TSA liquids, and has the added disadvantage of trapping the silylamine product. This results in additional losses in TSA yield, and requires special handling to dispose of the ammonium chloride. In addition, the liquid phase reaction allows the formation of other undesirable compounds, such as N,N',N"-trimethylsilylcyclotrisilazane, and disproportionation occurs at least at temperatures of about 0°C (reaction (6)), although slowly in the liquid phase at 0°C.

[0025] It can be seen that current practices may not be adequate for all situations and may result in the need for more separation steps and / or result in lower TSA recoveries. There remains a need for more robust TSA preparation methods and systems. The methods and systems of the present disclosure address these needs. Summary of the invention

[0026] According to the present disclosure, methods and systems are described that reduce or overcome many of the drawbacks of previously known systems and methods. The systems and methods of the present disclosure allow for large-scale production of TSA in the gas phase, are easy to operate, and are more selective for TSA than DSA. In addition, a product comprising TSA, DSA, and other byproducts can be passed to a separation system to separate DSA from TSA and convert DSA to TSA without forming solid ammonium halide in the TSA product.

[0027] A first aspect of the present disclosure is a system for the vapor phase synthesis of trisilylamine, which in certain embodiments comprises:

[0028] (a) a reaction vessel (2), the reaction vessel having a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0029] (b) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0030] (c) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0031] (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

[0032] It should be understood that in certain embodiments, the baffles may be replaced by (or may include in addition to) one or more other separation devices, such as packing, screens, trays, walls, dividers, grids, etc. In certain embodiments, the reaction vessel (2) may be cylindrical in shape and have a length (L), a diameter (D), and an L / D ratio, wherein the L / D ratio is in the range of about 0.1 to about 100, or about 1 to about 10.

[0033] In certain embodiments, the reaction product collection conduit (36) may include a particulate filter.

[0034] Certain embodiments may include a heating and / or cooling subsystem (H / C) that is thermally connected to at least the reaction zone (3) for temperature control. In certain embodiments, the heating and / or cooling subsystem (H / C) may be configured to maintain the reaction zone (3) at a temperature in the range of about -20°C to about 180°C, or about 10°C to about 150°C, or about 40°C to about 150°C.

[0035] Certain embodiments may include a condensation trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and configured to be maintained at a temperature in the range of about -10°C to about -80°C to remove silylamines from the reaction products, or configured to be maintained at a temperature in the range of about -20°C to about -40°C to remove silylamines from the reaction products.

[0036] In certain embodiments, the reaction vessel (2) may be configured to operate under temperature and pressure conditions such that ammonia, monohalosilane, and the reaction product silylamine are all in the gas phase. In certain embodiments, the reaction vessel (2) may be configured to operate under a pressure in the range of about 0.01 bar to about 15 bar (about 1 kPa to about 1500 kPa), or about 0.1 bar to 10 bar (about 10 kPa to about 1000 kPa), or about 0.2 bar to about 5 bar (about 20 kPa to about 500 kPa). In certain embodiments, the reaction vessel (2) may be configured to operate under temperature and pressure conditions such that ammonia, monohalosilane, and the reaction product silylamine are all in the gas phase.

[0037] In certain embodiments, one or more guide plates (32) may be selected from the group consisting of flat plate guide plates (32, 32C), corrugated plate guide plates (32A) and conical guide plates (32B), and one or more guide plates (32, 32A, 32B and 32C) may be supported by a bracket selected from the group consisting of two or more suspension support brackets (28, 30) connected at or near the top (7) of the reaction vessel (2) and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

[0038] Certain embodiments may also include a disproportionation unit (101) comprising a distillation column (120) fluidly connected to a condensate trap (51) via a feed conduit (122), a disproportionation reactor (126), a condenser (132), and a liquid reservoir (136). In these embodiments, the condensate trap (51) is fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2). The distillation unit (120) is fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142) can direct a TSA-rich stream from the distillation unit (120) to mix with TSA in the product conduit (36). The disproportionation reactor (126) has a disproportionation product conduit (128) and a conduit (130) for directing ammonia and volatiles to a condenser (132), the condenser (132) having a conduit (134) for directing DSA liquid to a reservoir (136), and the reservoir (136) having a recirculation conduit (140) and a recirculation pump (138) for directing DSA liquid from the reservoir (136) to the disproportionation reactor (126).

[0039] Certain embodiments may include one or more redundant components, such as two or more pumps arranged in series or parallel flow relationship, or two or more separators arranged in series or parallel flow relationship. Embodiments with mixed parallel flow and series flow are also contemplated, such as an arrangement of four separators, wherein a first separator and a second separator are arranged in parallel with each other, a third separator and a fourth separator are arranged in parallel with each other, and wherein the first separator is in series with the third separator, and the second separator is in series with the fourth separator.

[0040] The second aspect of the present disclosure is a system for the gas phase synthesis of trisilylamine, which is similar to the system of the first aspect, but in certain embodiments, includes one or more turbulence-inducing mixing structures (60, 70) positioned in the reaction zone (3). In certain embodiments, the one or more turbulence-inducing mixing structures (60, 70) can be selected from the group consisting of one or more mechanical agitators (60) and one or more static mixers (70). In certain embodiments, the one or more mechanical agitators (60) can be selected from the group consisting of motor-driven impellers and magnetic agitators. In certain embodiments, the one or more static mixers (70) can be selected from the group consisting of porous ceramic materials, porous polymer materials, porous steel mesh materials, and similar materials, and the one or more static mixers (70) can be supported by a bracket, the bracket selected from the group consisting of two or more suspension support brackets (28, 30) connected to the top (7) of the reaction vessel (2) or near it, and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

[0041] A third aspect of the present disclosure is a system for gas phase synthesis of trisilylamine, the system comprising:

[0042] (a) a cyclonic reaction vessel (2), the cyclonic reaction vessel having a top (7), a bottom (9), a tapered sidewall segment (80), a tangential feed chamber (82) and a generally cylindrical sidewall segment (84), the tapered sidewall segment (80) connecting the generally cylindrical sidewall segment (84) and the bottom (9), the tangential feed chamber (82) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) and the tangential feed chamber (82) are configured to inject the ammonia and the monohalosilane substantially horizontally and tangentially into the generally cylindrical segment (84) and then into the tapered sidewall segment (80);

[0043] (b) one or more baffles (32C) having a peripheral edge (33), the one or more baffles (32C) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32C) and a separation zone (5) extending to the bottom (9) of the reaction vessel (2) below the one or more baffles (32C);

[0044] (c) the one or more guide plates (32C) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0045] (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

[0046] Certain embodiments may include a monohalosilane purification subsystem comprising:

[0047] a first separator (102) configured to receive an impure monohalosilane stream (4A) and produce a silane and lighter compound stream (108) and an enriched monohalosilane stream (106),

[0048] A second separator (104) is configured to receive the enriched monohalosilane stream (106) and produce a reactor feed monohalosilane stream (16) and a polysilane and heavier stream (112).

[0049] Certain embodiments may include a fluorine or fluorine plasma source (94) fluidly connected to the reaction vessel (2), the fluorine or fluorine plasma being suitable for cleaning the reaction vessel (2), the system also including a conduit for directing a clean exhaust stream to an exhaust or waste treatment system (90).

[0050] A fourth aspect of the present disclosure is a method for gas phase synthesis of trisilylamine using the system of the present disclosure. Certain method embodiments may include a) feeding gaseous ammonia and gaseous monohalosilane under pressure downwardly and substantially vertically into a reaction vessel toward a separation device in the reaction vessel, the reaction vessel having an inner wall; b) separating ammonium chloride solid from gaseous silylamine product in the reaction vessel by using the separation device and a gap between the separation device and the inner wall of the reaction vessel; and c) collecting the gaseous silylamine product. Certain other method embodiments may include a) feeding gaseous ammonia and gaseous monohalosilane under pressure into a reaction vessel downwardly and substantially vertically toward and through a turbulence inducing device in the reaction vessel, the reaction vessel having an inner wall; b) causing at least some of the ammonium chloride solids to deposit on the inner wall of the reaction vessel while forming a gaseous silylamine product; c) optionally, separating the ammonium chloride solids from the gaseous silylamine product within the reaction vessel by using a separation device and a gap between the separation device and the inner wall of the reaction vessel; and d) collecting the gaseous silylamine product. Certain other method embodiments may include a) injecting ammonia and monohalosilane substantially horizontally and tangentially into a generally cylindrical segment; b) causing the ammonia and monohalosilane to flow into a tapered sidewall segment of the reaction vessel connected to the generally cylindrical segment toward a separation device in the reaction vessel, the reaction vessel having an inner wall; c) separating ammonium chloride solids from gaseous silylamine products within the reaction vessel by using the separation device and a gap between the separation device and the inner wall of the reaction vessel; and d) collecting the gaseous silylamine products.

[0051] As used herein, the terms "MCS" and "DCS" represent monochlorosilane and dichlorosilane. However, those skilled in the art will appreciate that any monohalosilane or mixture thereof may be used to react with ammonia to prepare TSA. For simplicity, the terms MCS and DCS will represent all monohalosilanes and dihalosilanes, respectively. The term "product stream" means a composition consisting essentially of TSA and having about 2 mol % to about 4 mol % MCS, DCS, silane and other undesirable substances, and substantially free of solid ammonium chloride. As used herein, "separator" means a unit employing one or more separation techniques, including but not limited to cryogenic separation, membrane separation, adsorption medium separation, distillation, adsorption, stripping, washing, solvent extraction or a combination thereof. As used herein, "conduit" means a component or combination of components (as described in detail herein) that connects one or more units operatively and fluidically to one or more other units. As used herein, the terms "source" and "receiver" may refer to a pipeline, a storage tank, a sample container, a liquid storage cylinder, a tank truck or any combination thereof.

[0052] In certain embodiments, one or more logic devices may be provided to control the systems and methods of the present disclosure, and the logic devices may be configured to be operated and / or viewed from a human-machine interface (HMI) connected to the logic devices by wire or wireless. Certain embodiments may include one or more audible and / or visual warning devices configured to receive communications from the logic devices when a pressure rise (or fall) in a sensed pressure above (or below) a set point pressure, or one or more sensed concentrations or temperatures or both above one or more set points occurs. In certain embodiments, the occurrence of changes in other measured parameters outside of the expected range may also be warned. Other measured parameters may include, but are not limited to, gas flow rate, vapor flow rate, multiphase fluid flow rate, liquid flow rate, and density of any of these.

[0053] Certain system and method embodiments of the present disclosure may include using one or more logic devices and certain valves (e.g., as specified by customers, laws or regulations) to start or shut down one, more than one or all operating equipment, and shut down when an adverse event occurs. As used herein, the term "operating equipment" includes, but is not limited to, gas reactant feed sources, inert gas feed sources, separators, heat exchangers, conduits, pumps, valves, plasma sources, exhaust systems, etc.

[0054] Certain system and method embodiments of the present disclosure can be operated in a mode selected from the group consisting of automatic continuous mode, automatic periodic mode and manual mode. In certain embodiments, the one or more operating devices may include a prime mover selected from the group consisting of pneumatic, electric, fuel, hydraulic and combinations thereof.

[0055] In certain embodiments, pressure (P) and / or temperature (T) may be sensed within a reaction vessel, separator, TSA collection vessel, valve inlet, valve outlet, etc. Different embodiments may have different sensor strategies, such as a mass flow sensor / controller for one gaseous reactant sensing the mass flow rate within a supply conduit for that reactant, and a mass flow sensor / controller for another gaseous reactant sensing the mass flow rate within a second gaseous reactant feed conduit. All combinations of sensing T, P, and / or mass flow rates of reactants and reaction products are disclosed herein and are considered to be within the scope of the present disclosure.

[0056] The systems of the present disclosure may include pressure management components and associated components such as, but not limited to, pressure control devices (back pressure valves), pressure relief devices (valves or bursting discs), expansion valves, pipes, conduits, vessels, towers, tanks, mass flow meters, temperature and pressure indicators, heat exchangers, pumps, compressors, and expanders.

[0057] These and other features of the methods and systems of the present disclosure will become more apparent upon review of the accompanying drawings, the detailed description, and the subsequent claims. It should be understood that anywhere the term "comprising" is used herein, other embodiments in which the term "comprising" is replaced by "consisting essentially of..." are expressly disclosed herein, and vice versa. It should also be understood that anywhere the term "comprising" is used herein, other embodiments in which the term "comprising" is replaced by "consisting essentially of..." are expressly disclosed herein, and vice versa. In addition, the use of negative limitations can also be specifically contemplated; for example, certain guide plates and mixing devices may not contain any material that will catalyze the destruction of TSA. In certain embodiments, the MCS gaseous reactant may contain no more than 2 mole %, or no more than 1 mole %, or no more than trace amounts of DCS. For example, the fluorine-based gas may not contain any components that can react explosively with ammonium chloride solids. BRIEF DESCRIPTION OF THE DRAWINGS

[0058] The manner in which the objects and other desirable features of the present disclosure may be achieved is illustrated in the following description and accompanying drawings, in which:

[0059] Figures 1 to 4 is a high-level schematic process flow diagram of four non-limiting system and method embodiments according to the present disclosure, with some portions cut away, and Figure 4A For schematic illustration Figure 4 A schematic plan view of an embodiment of the invention;

[0060] Figure 1A , Figure 2A , Figure 3A , Figure 3B and Figure 4B To show Figures 1 to 4Schematic cross-sectional views of certain features of four embodiments schematically shown in FIG.

[0061] Figure 5 is a high-level schematic process flow diagram of a disproportionation unit including a disproportionation reactor, which may be used in conjunction with any of the systems and methods of the present disclosure, and in certain embodiments may be integrated into the systems and methods of the present disclosure;

[0062] Figures 6 to 9 is a schematic logic diagram of four method embodiments according to the present disclosure; and

[0063] Fig.10 and Fig.11 is a SEM photograph of solid ammonium chloride powder removed from a reactor of one embodiment of the system of the present disclosure.

[0064] However, it should be noted that Figures 1 to 5 , Figure 1A , Figure 2A , Figure 3A , Figure 3B , Figure 4A and Figure 4B The accompanying drawings are not drawn to scale and only illustrate typical system and method embodiments of the present disclosure. Figures 6 to 9 Only four of the many possible methods according to the present disclosure are shown. Therefore, the accompanying drawings should not be considered limiting of the scope, as the present disclosure may admit of other equally effective embodiments. The same reference numerals are used for similar or similar elements in several views. DETAILED DESCRIPTION

[0065] In the following description, many details are set forth to provide an understanding of the apparatus, system, and method disclosed in the present invention. However, it will be appreciated by those skilled in the art that the apparatus, system, and method disclosed herein may be practiced without these details, and that many variations or modifications may be made to the embodiments. All technical articles, U.S. published and unpublished patent applications, standards, U.S. patents, U.S. laws, and regulations cited herein are hereby expressly incorporated herein by reference, regardless of the page, paragraph, or portion to which they are cited.

[0066] In the case where the range of values ​​describes a parameter, all sub-ranges, point values ​​and endpoints within the range or limiting a certain range are explicitly disclosed herein. Unless otherwise indicated, all percentages herein are by weight. All physical properties, size and ratio ranges and the sub-ranges (including endpoints) between the range endpoints of those properties, sizes and ratios are considered to be explicitly disclosed herein. As used herein, with respect to pressure, "about" means + / -0.5 bar (+ / -50kPa). As used herein, with respect to temperature, "about" means + / -10 ° C. As used herein, with respect to aspect ratio (ratio of length to diameter, or L / D), "about" means + / -1 for values ​​below 10, and + / -5 for values ​​10 and above 10. As used herein, with respect to length and diameter, "about" means + / -10cm, and in certain embodiments, + / -5cm. As used herein, with respect to angles (including angles from horizontal and vertical), "about" means + / - 15 degrees, in certain embodiments means + / - 10 degrees, and in certain other embodiments means within + / - 5 degrees.

[0067] As described herein, one of the challenges of all liquid phase processes for preparing TSA is that they suffer from the fact that ammonium chloride actually catalyzes the decomposition of the TSA liquid, and ammonium halides have the added disadvantage of trapping the silylamine product. This results in additional loss of TSA yield and requires special handling to dispose of the ammonium halide. In addition, the liquid phase reaction allows the formation of other undesirable compounds, such as N,N',N"-trimethylsilylcyclotrisilazane, and disproportionation occurs at least at temperatures of about 0°C (reaction (6)), although it occurs slowly in the liquid phase at 0°C. In configurations contemplated outside of those disclosed herein, in order to use the TSA prepared in the liquid phase process, the reaction product containing TSA needs to be further processed, which not only incurs additional expenses, but also leads to waste disposal problems. The systems and methods of the present disclosure address these problems by using a gas phase reaction with one or more internal baffles in the reactor. In order to solve the problem of producing TSA with low or only trace amounts of ammonium halide solids, the internal baffles allow for the collection of TSA with low or only trace amounts of ammonium halide solids. Alternatively, or in combination with one or more baffles, the system can employ turbulent flow conditions in the reactor, rather than laminar flow conditions. Thus, the systems and methods of the present disclosure not only allow for the preparation of relatively pure TSA, but also solve the waste disposal problem, thereby saving costs in terms of reduced capital expenses and reduced operating expenses when compared to previously known systems and methods. None of the references discussed in the background art mention the use of one or more baffles or the use of turbulent reaction conditions, as taught in the present disclosure.

[0068] It is known that gaseous silyl halides react with gaseous ammonia to form gaseous silylamines and solid ammonium halides. Unlike liquid phase reactions, the solid ammonium halides formed in gas phase reactions do not catalyze the decomposition of TSA and do not trap the silylamine product. However, solid ammonium halides quickly clog the reactor as well as the feed and product ports, which reduces the available reaction volume and limits production capacity.

[0069] Surprisingly, it has been found that ammonium halide powder can be separated from gaseous stream using one or more guide plates positioned in the reaction vessel as described herein. The guide plate is preferably placed in a downward flow direction, wherein the gas is fed from the top of the reaction vessel. Most of the ammonium halide powder will be deposited on the guide plate. A small amount of powder will pass through with the steam. Surprisingly, it has been found that when the gap between the guide plate and the container wall is small enough, a part of the powder can be accumulated on the gap, so that the powder layer can serve as a filter to keep more powder while keeping the gaseous product passing through. The result is that solid ammonium halide and gaseous silylamine are completely separated. Not subject to any theoretical constraints, the inventor has reason to believe that one or more guide plates can generate eddies within and / or outside the direct reaction zone where the gases entering begin to react with each other. The reaction gas stream entering from the inlet of the reaction vessel, which is guided in a downward direction and mixed with the reaction intermediates and products present locally, can experience recirculation in an upward direction when impacting the surface of one or more guide plates. It is believed that such recirculation phenomena can destroy any laminar flow pattern present in the reaction zone, even in the absence of a physical mixing device such as an impeller. The inventors have determined that a recirculating flow pattern facilitates efficient mixing within the reaction zone, whereby AMC solids are deposited on available baffle surfaces including previously deposited AMC solids, and gaseous products escape through gaps between the baffles and the reaction vessel wall. It has also been surprisingly discovered that a mechanical mixing device can greatly promote the reaction between silyl halide and ammonia, which provides a higher ratio of TSA to DSA.

[0070] Now refer to the accompanying drawings, Figures 1 to 4 is a high-level schematic process flow diagram of four non-limiting system and method embodiments according to the present disclosure, with some portions cut away, and Figure 4A For schematic illustration Figure 4 A schematic plan view of an embodiment of the invention is provided in FIG. Figure 1A , Figure 2A , Figure 3A , Figure 3B and Figure 4B To show Figures 1 to 4 Schematic cross-sectional views of certain features of four embodiments schematically shown in FIG. For simplicity, features common to all system embodiments such as Figure 1 and Figure 1AThe reaction vessel length (L), diameter (D) and thermal control (H / C) shown are not shown in the remaining figures.

[0071] See first Figure 1 and Figure 1A , system embodiment 100 includes a reaction vessel (2), a MCS source (4) and an ammonia source (6). The flow rates of MCS and ammonia are controlled by mass flow controllers (8) and (10) through conduits (14) and (16) to an annular nozzle (12), thereby forming a first gas inlet and a second gas inlet (11, 13) leading to the reaction vessel (2). The reaction vessel (2) includes a top (7), a bottom (9) and a side wall (15), the latter having an inner surface (21) (see Figure 1A ). System embodiment 100 and other systems of the present disclosure may have a thermal control unit (H / C) for temperature control of the reaction vessel via heating or cooling. System 100 also includes an inert gas source (18) for directing an inert gas such as nitrogen, argon or other inert gases or mixtures thereof to the reaction vessel (2) via another mass flow controller (20) and a conduit (22) fluidly connected to a third gas inlet (17) in an outer conduit (24) of the annular nozzle (12). Other arrangements will be within the scope of the skilled person through suitable valves and manifolds. For example, the inert gas may be directed to only one of the gas reactant conduits.

[0072] See again Figure 1 , more specifically with reference to the components within cutout 26, the reaction vessel (2) includes an internal flat horizontal baffle (32) which effectively divides the internal volume of the reaction vessel (2) into a reaction zone (3) and a separation zone or product collection zone (5). Although, as described herein, the baffle (32) performs the primary separation function of separating solid ammonium halide from gaseous products, for convenience, the zone (5) will be referred to herein as the separation zone. Figure 1A Cutaway view shown Figure 1A-1A, the baffle (32) in this embodiment is a substantially flat disk having a peripheral edge (33) that is spaced apart from the inner surface (21) of the reaction vessel sidewall (15) by a gap (34). The gap (34) may be in the range of about 0.01 mm to about 10 mm, and in certain embodiments in the range of about 0.02 mm to about 5 mm. Multiple baffles may be installed with the same or reduced gaps to ensure minimal passage of halide powder into the downstream product stream. In embodiment 100, the baffle (32) is supported by a pair of baffle supports (28, 30). A reaction product collection conduit (36) having an inlet end (38) is positioned so that its inlet end (38) extends below the guide plate (32) and the remainder of the reaction product conduit (36) (in this embodiment) extends substantially vertically through the reaction zone (3), through the fitting (40) on the top (7) of the reaction vessel, and through the conduit (36) and valve (63) to a reaction product cooler (37) having a cooling fluid inlet (CFI) and a cooling fluid outlet (CFO). A cooled reaction product conduit (42) having a distal end (44) directs the cooled reaction products to a TSA collection vessel (46) which is isolated or immersed in a cooling bath equipped with a pressure gauge (48). The distal end (44) of the conduit (42) extends to a position near the bottom of the TSA collection vessel (46). A TSA supply conduit (50) with the aid of valves (57, 61) directs the TSA to a downstream semiconductor manufacturing process (such as but not limited to CVD) or to a storage device (59). Samples of TSA may be obtained via sample valves (56, 58). Valves (55, 57) may be used to isolate the TSA collection vessel (46). Bypass conduit (52) and bypass valve (54) may be used to bypass the product cooler (37) and product collection vessel (46) in certain operating modes, such as during inerting or purging operations or other maintenance. Other valves (not shown for simplicity) may be used to isolate the reaction vessel (2) and the product cooler (37).

[0073] System embodiment 100 also includes a condensate trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and configured to be maintained at a temperature in the range of about -10°C to about -80°C to remove the silylamine from the reaction products, or configured to be maintained at a temperature in the range of about -20°C to about -40°C to remove the silylamine from the reaction products. In certain embodiments, the condensed material from the condensate trap (51) can be directed to a waste (53) or a disproportionation unit, as described herein with reference to Figure 5 Further explanation.

[0074] See now Figure 2 and Figure 2A, embodiment 200 is similar to embodiment 100, but with different key features. One key feature is the replacement of the flat baffles (32) of embodiment 100 with corrugated baffles (32A), which provide a larger surface area than flat plates and allow more ammonium halide powder to be collected than flat plates, thereby allowing the system to run longer before cleaning. Another feature is the addition of a mechanical stirring device (60), in which an agitator having an impeller that rotates as shown by the curved arrow is added. A motor (62) and a shaft can be used to rotate the stirring impeller. Other embodiments may use a magnetic stirring device, in which a permanent magnet or electromagnet is used outside the reaction vessel (2) to cause movement of the ferromagnetic stirrer. Another difference between embodiments 100 and 200 is the injection nozzles (64, 66) provided to force the reaction gas MCS and ammonia to mix through the impact of the flow near the impeller (60), thereby further increasing the generation of turbulence. The mechanical mixer (60) should be capable of applying sufficient force so that the flow of the reactant gas has a Reynolds number (Re) at least in a transient flow state, wherein the transient flow Re is in the range of about 2300 to about 4000, and in certain embodiments, sufficient force so that the flow of the reactant gas has a Re under turbulent conditions, wherein Re>4000.

[0075] See now Figure 3 , Figure 3A and Figure 3B Embodiment 300 is similar to embodiment 100, but with different key features. One feature is that the reaction gases MCS and ammonia enter the reaction vessel (2) in parallel flow, rather than in annular flow as in embodiment 100. Figure 3 and Figure 3BSchematically, the gas inlets (11, 13) are arranged substantially side by side so that the flow of the reactant gas MCS flows in parallel as it enters the reaction vessel toward the static mixer (70), which may be one or more circular members made of a porous steel mesh (such as but not limited to steel wool), a porous ceramic material (such as but not limited to a ceramic grid), a porous polymer material, etc. The static mixer (70) is supported by support brackets (28, 30) in embodiment 300, but may be attached to the inner surface (21) of the reaction vessel (2) by a partial bracket (not shown). The static mixer (7) is used to induce turbulence or turbulence of the mixed reactants, but should have a sufficiently large void area so as not to impede the flow of the reactant gas beyond a degree sufficient to induce significant turbulence above laminar flow conditions. In other words, the static mixer (70) should be able to exert sufficient retardation so that the flow of the reactant gas has a Reynolds number in either transient or turbulent conditions, wherein transient flow Re is in the range of about 2300 to about 4000, and turbulent flow conditions have Re>4000. For example, the openings in the screen grid may be in the range of about 0.01 cm to about 5 cm, or about 0.1 cm to about 3 cm, or about 0.1 cm to about 1 cm.

[0076] Still see Figure 3 and Figure 3A , system embodiment 300 differs from embodiments 100 and 200 in that the conical guide plate (32B) having a cone angle "α" can be in the range of about 90 degrees to about 175 degrees, or about 100 degrees to about 160 degrees. The conical guide plate (32B) can have certain advantages. When the ammonium halide powder is collected on the conical guide plate, the accumulation amount toward the peripheral edge (33) of the conical guide plate should be greater than the accumulation amount on the area near the cone apex (72), thereby producing a filtering effect.

[0077] See now Figure 4 , Figure 4A and Figure 4B, embodiment 400 differs from embodiments 100, 200 and 300 in that a cyclone-shaped reaction vessel (2) has a conical segment (80), a tangential feed chamber (82) feeding a cylindrical segment (84), and an exhaust pipe (86). Under appropriate conditions, the cyclone-shaped reaction vessel (2) generates turbulence in the reaction zone to promote effective reactant gas phase mixing and sufficient reaction pathways with residence time. The conical segment (80) has a cone angle "β" ranging from about 45 degrees to just less than about 90 degrees, or from about 45 degrees to about 75 degrees, or from about 45 degrees to about 65 degrees. The cyclone-shaped reaction vessel (2) can be operated in a continuous mode or a semi-continuous mode. In one embodiment, the cyclone-shaped reaction vessel (2) can be operated in a continuous mode that allows gaseous reaction products to be separated from solid reaction products without the use of a guide plate. The reaction product solids fall under gravity toward the bottom (9) of the cyclone-shaped reaction vessel (2), thereby allowing them to be removed, while the vapor product stream is directed upward toward and exits from the top (7) of the cyclone-shaped reaction vessel (2). In one example, the vapor product may enter the bottom of the product conduit (36) and then flow in an upward direction within the product conduit (36) until exiting from the top (7) of the cyclone-shaped reaction vessel (2). Figure 4A The plan view schematically shows that the tangential feed chamber (82) directs the feed ammonia and MCS gaseous reactants tangentially into the cylindrical section (84) and then into the conical section (80) to achieve better reaction gas mixing and a longer reaction path. These embodiments may also allow solid / gas separation in a possible continuous operation mode, where solids fall under gravity and the vapor product stream flows upward. In another embodiment, the cyclone-shaped reaction vessel (2) may be configured to be equipped with one or more guide plates, thereby allowing embodiment 400 to operate in a batch mode (i.e., semi-continuous mode). Optionally, guide plates may also be used. As Figure 4B Section view in Figure 4B-4BAs shown, a circular flat plate baffle (32C) having a diameter less than the inner diameter (D) of the reaction vessel (2) is positioned near the bottom of the conical section (80), forming a reaction zone (3) and a separation zone (5) as in other embodiments, and is positioned so that a gap (34) exists between the peripheral edge (33) and the inner surface of the reaction vessel. In this embodiment, a local bracket (92) is used, which can be welded, brazed or otherwise attached to the reactor side wall and the flat baffle (32C). If a baffle is used, another advantage of embodiment 400 is that the product conduit (36) can be centered upward through the baffle (32C), the top (7) of the reaction vessel (2), and through the exhaust conduit (86). The exhaust conduit (87) can direct the reaction vessel exhaust from the exhaust conduit (86) to a downstream exhaust or waste treatment station (90). The product conduit (36) directs the TSA to a location such as Figures 1 to 3 The downstream processing equipment (product cooler (37), TSA collection vessel (46), etc.) or storage device (88) shown. Valve (145) can allow the disproportionation unit ( Figure 5 ) is mixed with the TSA produced in reaction vessel (2).

[0078] Other method and system embodiments may include one or more optional components and steps to perform dry cleaning in situ to remove or significantly reduce ammonium chloride (NH4Cl) deposits on reactor interiors, baffles, gas injection nozzles, and other equipment such as baffle supports. This can be accomplished using fluorine radicals (gaseous or plasma, or mixtures thereof, such as, but not limited to, thermal fluorine or fluorine plasma, ammonia plasma, etc.). Figure 4 A source (94) is shown providing fluorine, fluorine plasma, or other cleaning gas or plasma for cleaning the reaction vessel (2). For this purpose, a mass flow controller (96) and conduit (98) may be provided. Those skilled in the art will appreciate that appropriate valves and manifolds will be involved to block the flow of the reaction gases during the cleaning operation; for simplicity, these valves are not shown.

[0079] Certain method and system embodiments may include one or more optional MCS purification steps to reduce the DCS content in the raw MCS feed material. Due to reported stability issues with MCS, some undesirable DCS (and SiH4) may be formed in the raw MCS material during transport (disproportionation). Due to significant vapor pressure differences, one or more distillation steps may be effectively used. In certain embodiments, the DCS concentration in the MCS feed to the reactor may be set as a process control target. One such optional MCS purification subsystem is schematically shown in Figure 4, comprising, for example, a first separator (102, 104), the first separator (102) receiving a feed of MCA having impurities therein (raw MCS) from source 4A. The first separator (102) separates silane and lighter components from the raw MCS via conduit (108) and directs them to further processing or storage means (110), thereby producing a stream rich in MCS and heavier components, which is directed via conduit (106) to the second separator (104), or, if impurities heavier than MCS are not present, directly into a reaction vessel (2) via a bypass conduit (107). The top separator (104) consists essentially of pure MCS and is directed to the reaction vessel (2) via conduit (16), while components heavier than MCS are removed via a bottom conduit (112) for further processing (114).

[0080] See now Figure 5 It is known from Aylett and Hakim (1966) that DSA in liquid form can undergo a disproportionation reaction via reaction scheme (6) to form TSA and ammonia. However, it is known from Well and Schaeffer (1966) that the presence of ammonia can catalyze the elimination of silane from TSA via reaction scheme (8). Therefore, if the DSA disproportionation reaction is carried out in a closed vessel, the by-product ammonia will lead to a parallel elimination of silane from TSA and the formation of undesirable polysilazane products. Figure 5 One embodiment 101 of a DSA disproportionation unit useful for the systems and methods of the present disclosure is schematically illustrated and includes a distillation column (120), a disproportionation reactor (126), a condenser (132), a liquid reservoir (136), and a recirculation pump (138). A feed conduit (122) feeds condensed material received from condensate traps (51, 53) to produce a DSA overhead vapor stream, which is directed to the disproportionation reactor (126) via conduit (124). A TSA-rich stream is directed from the bottom of the distillation unit (120) to a storage device via conduit (142), or returned to mix with TSA collected from a TSA collection vessel (46) (see Figure 4). The DSA disproportionation reaction is carried out in a certain manner so that all ammonia formed in the reaction is removed simultaneously by evaporation, for example, through conduit (130). The ammonia vapor, which also contains some DSA vapor, is then passed through a condenser (132) to condense the DSA and reflux (via conduit (134), a reservoir (136), a recirculation pump (138) and a recirculation conduit (140) back to the disproportionation reactor (126). The uncondensed ammonia vapor is discharged for recycling or disposal through conduit (148). In certain embodiments, the DSA disproportionation reaction can be carried out directly from the collected TSA / DSA liquid. Alternatively, DSA together with other volatile impurities (such as silane) can be easily separated from TSA by evaporation or distillation, such as Figure 5 As shown. It is relatively simple to distill DSA from crude TSA because there is a significant difference in the boiling points of DSA (36°C) and TSA (52°C). In certain embodiments, the TSA / DSA separation unit (120) can be used in combination with a DSA disproportionation reactor (126) and an ammonia and volatile component separation unit so that all other volatile impurities such as ammonia and silane can be removed (146). The TSA / DSA product from the DSA disproportionation reactor (126) is directed to the TSA / DSA separation (distillation) unit (120) via a conduit (128). The final TSA effluent can then be directed to a final purification step (not shown) to remove low volatility polysilazanes before being directed to a downstream semiconductor manufacturing process or to a storage device (144). Solid ammonium halide is not formed in this system, which is very beneficial for operation and cleaning. The TSA thus obtained is not only of high purity but also free of dissolved ammonia, and is therefore stable for storage over a long period of time.

[0081] Figures 6 to 9 600 is a gas phase method for preparing trisilylamine, comprising (block 602):

[0082] (a) allowing ammonia and monohalosilane to flow into a reaction vessel (2), the reaction vessel comprising:

[0083] (i) a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9),

[0084] (ii) the reaction vessel (2) comprises a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0085] (iii) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0086] (iv) the one or more baffles (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0087] (v) a reaction product collection conduit (36) having an inlet end (38) positioned in the separation zone (5) (block 604);

[0088] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine (block 606);

[0089] (c) flowing at least a portion of the reaction products comprising trisilylamine through the reaction product collection conduit (36) (block 608); and

[0090] (d) depositing a majority of the powdered ammonium halide on the one or more baffles (32) (block 610).

[0091] Process embodiment 700 is a gas phase process for preparing trisilylamine, comprising (block 702):

[0092] (a) Ammonia and monohalosilane are flowed into a reaction vessel (2), the reaction vessel comprising (block 702):

[0093] (i) a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0094] (ii) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0095] (iii) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2);

[0096] (iv) one or more turbulence inducing mixing structures (60, 70), said one or more turbulence inducing mixing structures being positioned in said reaction zone (3); and

[0097] (v) a reaction product collection conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine (block 704);

[0098] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine (block 706);

[0099] (c) flowing at least a portion of the reaction products comprising trisilylamine through the reaction product collection conduit (36) (block 708); and

[0100] (d) depositing a majority of the powdered ammonium halide on the one or more baffles (32) (block 710).

[0101] Process embodiment 800 is a gas phase process for preparing trisilylamine, comprising (block 802):

[0102] (a) allowing ammonia and monohalosilane to flow into a reaction vessel (2), the reaction vessel comprising:

[0103] (i) a cyclonic reaction vessel (2), the cyclonic reaction vessel having a top (7), a bottom (9), a conical sidewall segment (80), a tangential feed chamber (82) and a generally cylindrical sidewall segment (84), the conical sidewall segment (80) connecting the generally cylindrical sidewall segment (84) and the bottom (9), the tangential feed chamber (82) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) and the tangential feed chamber (82) are configured to inject the ammonia and the monohalosilane substantially horizontally and tangentially into the generally cylindrical segment (84) and then into the conical sidewall segment (80);

[0104] (ii) one or more baffles (32C) having a peripheral edge (33), the one or more baffles (32C) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32C) and a separation zone (5) extending to the bottom (9) of the reaction vessel (2) below the one or more baffles (32C);

[0105] (iii) the one or more guide plates (32C) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0106] (iv) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine (804);

[0107] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product (806) comprising trisilylamine;

[0108] (c) flowing at least a portion of the reaction products comprising trisilylamine through the reaction product collection conduit (36) (block 808); and

[0109] (d) depositing a majority of the powdered ammonium halide on the one or more baffles (32) (block 810).

[0110] Process embodiment 900 is a gas phase process for preparing trisilylamine, comprising (block 902):

[0111] (a) flowing ammonia and monohalosilane into a top portion (7) of a reaction vessel (2), the reaction vessel comprising one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a location in the reaction vessel (2) to define a reaction zone (3) extending to the top portion (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom portion (9) of the reaction vessel (2) below the one or more baffles (32), the one or more baffles (32) being positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and an inner surface (21) of the reaction vessel (2), the reaction vessel (2) comprising a condensate trap (51) fluidly connected to the separation zone (5) at or near the bottom portion (9) of the reaction vessel (2) (block 904);

[0112] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product (906) comprising trisilylamine;

[0113] (c) flowing at least a portion of the reaction products comprising trisilylamine through a reaction product collection conduit (36) (block 908);

[0114] (d) depositing a majority of the powdered ammonium halide on the one or more baffles (32) (block 910). and

[0115] (e) flowing the condensed material from the condensate trap (51) to a disproportionation unit (101), the disproportionation unit comprising a distillation column (120) fluidly connected to the condensate trap (51) via a feed conduit (122), a disproportionation reactor (126), a condenser (132) and a liquid reservoir (136), the distillation column (120) being fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142) for directing a TSA-rich stream to mix with TSA in a product conduit (36),

[0116] directing ammonia and volatiles from the disproportionation reactor (126) to the condenser (132) via a conduit (130),

[0117] directing the DSA / TSA mixture from the disproportionation reactor (126) through the disproportionation product conduit (128) to the feed conduit (122),

[0118] directing DSA liquid from the condenser (132) to the reservoir (136) via a conduit (134), and

[0119] DSA liquid is directed from the reservoir (136) through a recirculation conduit (140) and a recirculation pump (138) to the disproportionation reactor (126) (block 912).

[0120] The geometry of the reaction vessel (2) may be cylindrical, rectangular, conical or a combination thereof, wherein the aspect ratio (L / D) is from 0.1 to 100, preferably from 1 to 10. For non-circular cross-sections, the diameter of the reaction vessel may be expressed as the hydraulic diameter, or D h =4A / P, wherein A is the cross-sectional area of ​​the reaction vessel, and p is the wetted periphery. The volume of the container can be as large as possible so that the reaction can be carried out continuously with only a short interruption for cleaning. After each reaction batch or half batch, the solid ammonium halide can be directly removed and collected in a dry state without the use of water, and the water is relatively pure and can be utilized in an appropriate manner in the absence of silylamine. This greatly reduces the processing and disposal costs of the ammonium halide. The feed nozzles of silyl halides and ammonia can be arranged in a typical feed configuration, such as but not limited to co-current flow, annular flow or impact flow mode. The mixing device can be arranged to promote the flow existing from the nozzle in at least a transient flow mode and preferably a turbulent mode.

[0121] In a preferred embodiment, reaction temperature and pressure are not limited, but it is necessary to keep the feed and silylamine product in a gaseous state. The temperature can generally be in the range of about -20 ° C to about 180 ° C, or about 10 ° C to about 150 ° C, or about 40 ° C to about 150 ° C. The reaction pressure can generally be in the range of about 0.01 bar to about 15 bar (about 1 kPa to about 1500 kPa), or about 0.1 bar to 10 bar (about 10 kPa to about 1000 kPa), or about 0.2 bar to 5 bar (about 20 kPa to about 500 kPa). Due to the exothermic nature of the reaction, cooling can be increased to maintain the desired temperature. Cooling can be provided via heat transfer from the container wall or internal coil.

[0122] In the reactant feed without any additional mechanical mixing, such as those described in U.S. Patent No. 8,409,513B2, silyl halides and ammonia react instantaneously and deposit solid ammonium halides on the feed nozzle. Solid deposits grow along the contact surface of the reactants, which not only gradually reduces the mixing of the reactants, but also increases the possibility of clogging of the feed nozzle and the container wall. Solid deposits on the container wall are also difficult to remove, making the cleaning of the reaction vessel extremely time-consuming. In certain embodiments of the present disclosure, mechanical mixing devices and / or static mixers may be added to promote the mixing of the reaction gases. With appropriate mixing devices, such as those described with reference to the embodiments of the present disclosure, the formation of solid deposits on the feed nozzle and the container wall is reduced, and most of the solid ammonium halides remain in powder form, which can be transported downstream and separated from the gaseous products by one or more guide plates or other separation devices such as fillers, screens, trays, walls, partitions, grids, etc.

[0123] It has also been surprisingly found that mechanical mixing devices can greatly promote the reaction between silyl halides and ammonia, which provides a higher ratio of TSA to DSA. This in turn minimizes the load of converting DSA to TSA. Although the conversion of DSA to TSA can be carried out by reaction schemes (3) or (8) with excess silyl halides, the conversion results in the formation of solid ammonium halide in the TSA / DSA liquid mixture, which requires additional separation steps. The separated ammonium halide still contains part of TSA / DSA, so a special waste treatment process is required. Additional separation steps are also required to separate and recycle excess silyl halides to reduce costs.

[0124] Example

[0125] Example 1

[0126] A cylindrical stainless steel reactor with an L / D ratio of 10, an internal volume of 8 L and an internal diameter (D) of 10 cm was used. A flat, substantially horizontal stainless steel baffle with a diameter of 9.8 cm was installed in the bottom section of the reactor. The volume below the baffle was about 1.5 L. Gaseous ammonia (supplied from a tank at T = 28 ° C. controlled by MFC and regulated to P = 3 bar) and gaseous MCS (also supplied from a tank at T = 28 ° C. controlled by MFC and regulated to P = 3 bar) were added as follows Figure 1 The annular flow pattern shown is fed into the top of the reactor which is maintained at T = 30 to 140°C and p = 0.3 to 0.5 bar. Figure 1The vapor product was extracted from a conduit connected to the downstream of the guide plate in the manner shown. No particle filter was used in the vapor product conduit. Gaseous ammonia was fed into the reactor at a rate of 1.93 L / min. Monochlorosilane was fed into the reactor at a rate of 1.49 L / min. The reaction lasted 256 minutes and was stopped by shutting off the feed gas when the vapor product conduit was partially blocked, as confirmed by the gradual increase in reactor pressure. About 1 / 2 of the ammonium chloride produced was in powder form (powder at Fig.10 and Fig.11 ) is shown in the photo of , thereby accumulating on the guide plate. The remaining solids are deposited on the reactor wall and the feed nozzle. The gas reaction forms disilylamine, trisilylamine and ammonium chloride. The amount of ammonium chloride collected is 739.8g. The amount of product vapor condensed and collected at -30°C is 444g. Based on online GC-TCD analysis ("GC-TCD" is a gas chromatograph with a thermal conductivity detector), the ratio of DSA to TSA is about 2.5. The total yield of TSA is 78%. The GC-TCD equipment used: chromatographic column: DB-1, 105m, 0.53mm ID, 5 micron film. GC is an Agilent 7820 with a TCD detector. The temperature program was initially isothermal at 35°C for 5 minutes, then ramped to 175°C at a rate of 14°C / min, and kept isothermal for another 12 minutes.

[0127] Example 2

[0128] The same reactor as in Example 1 was used, except that a mechanical magnetic stirrer was installed on the top of the reactor and two guide plates stacked in parallel were installed at the bottom of the reactor with a spacing of 5 cm. The volume below the guide plates was about 2.5 L. The mixing impeller was operated at a speed similar to that of Figure 2 The reactor was positioned close to the feed nozzle and below the feed nozzle in a manner of .93 L / min of gaseous ammonia (at 28 ° C and 3 bar). The reactor was fed with gaseous monochlorosilane (at 28 ° C and 3 bar) at a rate of 1.49 L / min. The reaction lasted 400 minutes and the vapor product line was not blocked. About 3 / 4 of the ammonium chloride produced was in powder form ( Fig.10 and Fig.11 ), thereby accumulating on the guide plate. The remaining solids were mainly deposited on the reactor wall, and rarely on the feed nozzle. The amount of ammonium chloride collected was 1234.6 g. The amount of product vapor condensed and collected at -30°C was 806.7 g. Based on online GC-TCD analysis, the ratio of DSA to TSA was about 0.4. The total yield of TSA was 87%.

[0129] As shown in the examples herein, most of the ammonium halide powder accumulates on the guide plate and remains in a loose form without blocking the gap between the guide plate and the reaction vessel wall. In the absence of a mechanical mixing device, most particles aggregate together, eventually forming a solid mass and blocking the container and nozzle. Fig.10 and Fig.11 SEM photos of ammonium chloride powder generated during Example 2 are shown. The ammonium chloride particle size is in the range of 1 μm to 5 μm (micrometers). The particles are loosely packed and remain free-flowing, which allows easy removal in a short time. Elemental analysis of the powder shows only nitrogen and chlorine without any detectable silicon. This confirms the absence of silyl chloride or other silicon byproducts deposited on the powder.

[0130] The systems and subsystems of the present disclosure may be constructed to meet ISO standards, SEMI (formerly Semiconductor Equipment and Materials International) standards, American Bureau of Standards (ABS) standards, American Society for Testing and Materials (ASTM) standards, and / or other standards.

[0131] If used, the electrical connections (voltage and amperage) will be applicable to the zone ratings required for each system. In certain embodiments, one or more cables may be extended at the workplace and connected to the identified power source to operate the HMI, gas feed supply source, gas cabinet, etc. Certain embodiments may use a dedicated power source. The identified or dedicated power source may be controlled by one or more logic devices so that it can be turned off. In an exemplary embodiment, the system of the present disclosure may have an electrical isolation (locking) device on the safety cabinet.

[0132] In embodiments where it is desired to connect to one or more remote HMI units, this can be achieved through intrinsically safe cables and connections to allow system components to operate in the desired partitioned area. If remote access is not required, the power for the operating system and subsystems can be integrated with a device (such as a battery, for example but not limited to a lithium-ion battery). In these embodiments, the power source can be enclosed, allowing it to operate in a partitioned area (zone 0 (gas) according to the International Electrotechnical Commission (IEC) method). The so-called "intrinsic safety" means the definition of intrinsic safety used in the relevant IEC equipment standard IEC 60079-11, which is defined as a type of protection based on electrical energy limitations within the equipment and interconnecting wiring exposed to a potentially explosive atmosphere to a level below that at which ignition can be caused by sparks or thermal effects. For more discussion, see "AN9003-A User's Guide to Intrinsic Safety", retrieved from the Internet on July 12, 2017, which is incorporated herein by reference.

[0133] In certain embodiments, an internal algorithm in a logic device such as a PLC can calculate the rate of increase or decrease of pressure and temperature inside a reaction vessel and / or other devices and units described herein. The data can then be displayed or heard in a series of ways, such as a "closed percentage" indicator light or sound on one or more GUIs. In certain embodiments, an additional function within the HMI can be to sound an audible alarm when the calculated rate of increase or decrease of pressure or temperature reaches a level set by the operator.

[0134] The reaction vessels, baffles, baffle supports, static and mechanical mixers, supply and exhaust conduits, separators, pumps, logic devices, sensors, and other equipment described herein should be able to withstand long-term exposure to possible liquids and vapors encountered in the semiconductor manufacturing environment, including acids, acid gases, and fluids commonly encountered in semiconductor manufacturing facilities and cryogenic processing facilities.

[0135] In alternative embodiments, the reaction vessel and various subsystems and gaseous material supply sources may be enclosed in a rack or cabinet and / or be vehicle-mounted and / or rail-mounted. In addition, various components (such as reaction vessels, baffles, baffle supports, mixers, separators, distillation towers, etc.) do not need to have a specific shape or specific conduit wiring as shown, but may be in any shape, such as a box, a cube or other rectangular shape, an ellipse, a triangle, a prism, a hemispherical or quasi-hemispherical (dome shape) or a combination thereof, as long as the device performs one or more desired functions shown herein. Reactors, conduits, and tower cross-sections do not have to be circular, but may be rectangular, triangular, circular, elliptical, etc. It should be understood that such embodiments are part of the present disclosure and are considered to be within the scope of the claims. In addition, one or more of the various components may be decorated with various decorations made in various ways (e.g., embossing or engraving, or raised features such as reflectors, reflective tapes), such as facility designs, operating company designs, logos, letters, words, aliases (e.g., PPMI, LINDE, etc.).

[0136] Thus, the systems and methods described herein provide a way to safely and economically prepare trisilylamine.

[0137] Embodiments disclosed herein include:

[0138] A: A system for the vapor phase synthesis of trisilylamine, the system comprising (or consisting essentially of, or consisting of):

[0139] (a) a reaction vessel (2), the reaction vessel having a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0140] (b) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0141] (c) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0142] (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

[0143] B: A system for the vapor phase synthesis of trisilylamine, the system comprising (or consisting essentially of, or consisting of):

[0144] (a) a reaction vessel (2), the reaction vessel having a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0145] (b) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0146] (c) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2);

[0147] (d) one or more turbulence inducing mixing structures (60, 70), said one or more turbulence inducing mixing structures being positioned in said reaction zone (3); and

[0148] (e) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

[0149] C: A system for the vapor phase synthesis of trisilylamine, the system comprising (or consisting essentially of, or consisting of):

[0150] (a) a cyclonic reaction vessel (2), the cyclonic reaction vessel having a top (7), a bottom (9), a tapered sidewall segment (80), a tangential feed chamber (82) and a generally cylindrical sidewall segment (84), the tapered sidewall segment (80) connecting the generally cylindrical sidewall segment (84) and the bottom (9), the tangential feed chamber (82) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) and the tangential feed chamber (82) are configured to inject the ammonia and the monohalosilane substantially horizontally and tangentially into the generally cylindrical segment (84) and then into the tapered sidewall segment (80);

[0151] (b) one or more baffles (32C) having a peripheral edge (33), the one or more baffles (32C) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32C) and a separation zone (5) extending to the bottom (9) of the reaction vessel (2) below the one or more baffles (32C);

[0152] (c) the one or more guide plates (32C) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0153] (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

[0154] D: A gas phase process for preparing trisilylamine, the gas phase process comprising (or consisting essentially of, or consisting of) the following steps:

[0155] (a) allowing ammonia and monohalosilane to flow into a reaction vessel (2), the reaction vessel comprising:

[0156] (i) a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9),

[0157] (ii) the reaction vessel (2) comprises a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0158] (iii) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0159] (iv) the one or more baffles (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0160] (v) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5);

[0161] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine;

[0162] (c) flowing at least a portion of the reaction product comprising trisilylamine through the reaction product collection conduit (36); and

[0163] (d) depositing a majority of the powdered ammonium halide on the one or more guide plates (32).

[0164] E: A gas phase process for preparing trisilylamine, the gas phase process comprising (or consisting essentially of, or consisting of) the following steps:

[0165] (a) allowing ammonia and monohalosilane to flow into a reaction vessel (2), the reaction vessel comprising:

[0166] (i) a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2);

[0167] (ii) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32);

[0168] (iii) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2);

[0169] (iv) one or more turbulence inducing mixing structures (60, 70), said one or more turbulence inducing mixing structures being positioned in said reaction zone (3); and

[0170] (v) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine;

[0171] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine;

[0172] (c) flowing at least a portion of the reaction product comprising trisilylamine through the reaction product collection conduit (36); and

[0173] (d) depositing a majority of the powdered ammonium halide on the one or more guide plates (32).

[0174] F: A gas phase process for preparing trisilylamine, the gas phase process comprising (or consisting essentially of, or consisting of) the following steps:

[0175] (a) allowing ammonia and monohalosilane to flow into a reaction vessel (2), the reaction vessel comprising:

[0176] (i) a cyclonic reaction vessel (2), the cyclonic reaction vessel having a top (7), a bottom (9), a conical sidewall segment (80), a tangential feed chamber (82) and a generally cylindrical sidewall segment (84), the conical sidewall segment (80) connecting the generally cylindrical sidewall segment (84) and the bottom (9), the tangential feed chamber (82) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) and the tangential feed chamber (82) are configured to inject the ammonia and the monohalosilane substantially horizontally and tangentially into the generally cylindrical segment (84) and then into the conical sidewall segment (80);

[0177] (ii) one or more baffles (32C) having a peripheral edge (33), the one or more baffles (32C) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32C) and a separation zone (5) extending to the bottom (9) of the reaction vessel (2) below the one or more baffles (32C);

[0178] (iii) the one or more guide plates (32C) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and

[0179] (iv) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine;

[0180] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine;

[0181] (c) flowing at least a portion of the reaction product comprising trisilylamine through the reaction product collection conduit (36); and

[0182] (d) depositing a majority of the powdered ammonium halide on the one or more guide plates (32).

[0183] G: A gas phase process for preparing trisilylamine, the gas phase process comprising (or consisting essentially of, or consisting of) the following steps:

[0184] (a) flowing ammonia and monohalosilane into a top portion (7) of a reaction vessel (2), the reaction vessel comprising one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top portion (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom portion (9) of the reaction vessel (2) below the one or more baffles (32), the one or more baffles (32) being positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and an inner surface (21) of the reaction vessel (2), the reaction vessel (2) comprising a condensate trap (51) fluidly connected to the separation zone (5) at or near the bottom portion (9) of the reaction vessel (2);

[0185] (b) flowing the ammonia and the monohalosilane substantially vertically downward from the top (7) of the reaction vessel (2) to produce a reaction product comprising trisilylamine;

[0186] (c) passing at least a portion of the reaction product comprising trisilylamine through a reaction product collection conduit (36);

[0187] (d) depositing a majority of the powdered ammonium halide on the one or more baffles (32). and

[0188] (e) flowing the condensed material from the condensate trap (51) to a disproportionation unit (101), the disproportionation unit comprising a distillation column (120) fluidly connected to the condensate trap (51) via a feed conduit (122), a disproportionation reactor (126), a condenser (132) and a liquid reservoir (136), the distillation column (120) being fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142) for directing a TSA-rich stream to mix with TSA in a product conduit (36),

[0189] directing ammonia and volatiles from the disproportionation reactor (126) to the condenser (132) via a conduit (130),

[0190] directing the DSA / TSA mixture from the disproportionation reactor (126) through the disproportionation product conduit (128) to the feed conduit (122),

[0191] directing DSA liquid from the condenser (132) to the reservoir (136) via a conduit (134), and

[0192] DSA liquid is directed from the reservoir (136) to the disproportionation reactor (126) through a recirculation conduit (140) and a recirculation pump (138).

[0193] Each of embodiments A, B, C, D, E, F and G may have one or more of the following additional elements in any combination:

[0194] Element 1. The reaction vessel (2) is cylindrical in shape and has a length (L), a diameter (D) and an L / D ratio, wherein the L / D ratio is in the range of about 0.1 to about 100, or about 1 to about 10.

[0195] Element 2. The reaction product collection conduit (36) includes a particle filter.

[0196] Element 3. A heating and / or cooling subsystem (H / C) which is thermally connected to at least the reaction zone (3) for temperature control.

[0197] Element 4: The heating and / or cooling subsystem (H / C) is configured to maintain the reaction zone (3) at a temperature in the range of about -20°C to about 180°C, or about 10°C to about 150°C, or about 40°C to about 150°C.

[0198] Element 5: A condensation trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and configured to be maintained at a temperature in the range of about -10°C to about -80°C to remove silylamine from the reaction products.

[0199] Element 6: A condensation trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and configured to be maintained at a temperature in the range of about -20°C to about -40°C to remove silylamine from the reaction products.

[0200] Element 7: The reaction vessel (2) is configured to operate at a pressure in the range of about 0.01 bar to about 15 bar (about 1 kPa to about 1500 kPa), or about 0.1 bar to 10 bar (about 10 kPa to about 1000 kPa), or about 0.2 bar to about 5 bar (about 20 kPa to about 500 kPa).

[0201] Element 8: The reaction vessel (2) is configured to operate under temperature and pressure conditions such that the ammonia, the monohalosilane, and the reaction products are all in the gas phase.

[0202] Element 9: The one or more guide plates (32) are selected from the group consisting of flat plate guide plates (32, 32C), corrugated plate guide plates (32A) and conical guide plates (32B), and the one or more guide plates (32, 32A, 32B and 32C) are supported by a bracket, which is selected from the group consisting of two or more suspension support brackets (28, 30) connected to the top (7) of the reaction vessel (2) or near the top and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

[0203] Element 10: The method and system are configured to operate in a mode selected from the group consisting of an automatic continuous mode, an automatic periodic mode, and a manual mode.

[0204] Element 11: a disproportionation unit (101), the disproportionation unit comprising a distillation column (120), a disproportionation reactor (126), a condenser (132), and a liquid reservoir (136), the distillation column (120) being fluidly connected to a condensation trap (51) via a feed conduit (122), the condensation trap (51) being fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2), the distillation unit (120) being fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142), the TSA-rich stream conduit (143) The SA stream conduit is used to guide the TSA-rich stream to mix with the TSA in the product conduit (36), the disproportionation unit (126) has a disproportionation product conduit (128) and a conduit (130) for guiding ammonia and volatiles to the condenser (132), the condenser (132) has a conduit (134) for guiding DSA liquid to the reservoir (136), and the reservoir (136) has a recirculation conduit (140) and a recirculation pump (138) for guiding DSA liquid from the reservoir (136) to the disproportionation reactor (126).

[0205] Element 12: The method and system include an HMI including a display having an interactive graphical user interface.

[0206] Element 13: The one or more turbulence inducing mixing structures (60, 70) are selected from the group consisting of one or more mechanical agitators (60) and one or more static mixers (70).

[0207] Element 14: The one or more mechanical stirrers (60) are selected from the group consisting of a motor-driven impeller and a magnetic stirrer.

[0208] Element 15: The one or more static mixers (70) are selected from the group consisting of porous ceramic materials, porous steel mesh materials and similar materials, and the one or more static mixers (70) are supported by a bracket, which is selected from the group consisting of two or more suspension support brackets (28, 30) connected to the top (7) of the reaction vessel (2) or near the top and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

[0209] Element 16: a monohalosilane purification subsystem, the monohalosilane purification subsystem comprising:

[0210] a first separator (102) configured to receive an impure monohalosilane stream (4A) and produce a silane and lighter compound stream (108) and an enriched monohalosilane stream (106),

[0211] A second separator (104) is configured to receive the enriched monohalosilane stream (106) and produce a reactor feed monohalosilane stream (16) and a polysilane and heavier stream (112).

[0212] Element 17: A source of fluorine or fluorine plasma (94) or other cleaning gas or plasma, which is fluidly connected to the reaction vessel (2), the fluorine or other gas, fluorine plasma or other plasma being suitable for cleaning the reaction vessel (2), the system also including a conduit for directing a clean exhaust gas stream to an exhaust or waste treatment system (90).

[0213] Based on the above detailed description of specific embodiments, it should be apparent that patentable systems and methods have been described. Although specific embodiments of the present disclosure have been described in considerable detail herein, this is done solely for the purpose of describing the various features and aspects of the systems and methods and is not intended to be limiting with respect to their scope. It is contemplated that various substitutions, changes and / or modifications may be made to the embodiments without departing from the scope of the appended claims, including but not limited to those specific implementation variations that may have been proposed herein. For example, one modification would be to deploy redundant valves for safety purposes. Certain systems and methods of the present disclosure may not have certain steps, components and / or features: for example, systems and methods without a disproportionation unit; systems and methods without a separator located upstream of the reaction vessel; and methods without a recirculation pump in the disproportionation unit.

Claims

1. A system for the gas phase synthesis of trisilylamine, comprising: (a) a reaction vessel (2), the reaction vessel having a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2); (b) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32); (c) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

2. A system according to claim 1, wherein the reaction vessel (2) is cylindrical in shape and has a length (L), a diameter (D) and an L / D ratio, wherein the L / D ratio is in the range of 0.1 to 100, or 1 to 10.

3. The system of claim 1, wherein the reaction product collection conduit (36) comprises a particulate filter.

4. The system according to claim 1, comprises a heating and / or cooling subsystem (H / C), which is thermally connected to at least the reaction zone (3) for temperature control.

5. A system according to claim 4, wherein the heating and / or cooling subsystem (H / C) is configured to maintain the reaction zone (3) at a temperature in the range of -20°C to 180°C, or 10°C to 150°C, or 40°C to 150°C.

6. The system according to claim 1 further comprises a condensation trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and configured to be maintained at a temperature in the range of -10°C to -80°C to remove silylamine from the reaction products.

7. The system according to claim 1 further includes a condensation trap (51) which is fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2) and is configured to be maintained at a temperature in the range of -20°C to -40°C to remove silylamine from the reaction products.

8. The system of claim 1, wherein the reaction vessel (2) is configured to operate at a pressure in the range of 0.01 bar to 15 bar (1 kPa to 1500 kPa), or 0.1 bar to 10 bar (10 kPa to 1000 kPa), or 0.2 bar to 5 bar (20 kPa to 500 kPa).

9. The system of claim 1, wherein the reaction vessel (2) is configured to operate under temperature and pressure conditions such that the ammonia, the monohalosilane, and the reaction products are all in the gas phase.

10. A system according to claim 1, wherein the one or more guide plates (32) are selected from the group consisting of flat plate guide plates (32, 32C), corrugated plate guide plates (32A) and conical guide plates (32B), and the one or more guide plates (32, 32A, 32B and 32C) are supported by a bracket, which is selected from the group consisting of two or more suspension support brackets (28, 30) connected to the top (7) of the reaction vessel (2) or near the top and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

11. The system of claim 1 , further comprising a disproportionation unit ( 101 ), the disproportionation unit comprising a distillation column ( 120 ) fluidly connected to a condensate trap ( 51 ) via a feed conduit ( 122 ), the condensate trap ( 51 ) fluidly connected to the separation zone ( 5 ) at or near the bottom ( 9 ) of the reaction vessel ( 2 ), a disproportionation reactor ( 126 ) via a conduit ( 124 ), a condenser ( 132 ) and a liquid reservoir ( 136 ). ), the TSA-rich stream conduit is used to guide the TSA-rich stream to mix with TSA in the product conduit (36), the disproportionation unit (126) has a disproportionation product conduit (128) and a conduit (130) for guiding ammonia and volatiles to the condenser (132), the condenser (132) has a conduit (134) for guiding DSA liquid to the reservoir (136), and the reservoir (136) has a recirculation conduit (140) and a recirculation pump (138) for guiding DSA liquid from the reservoir (136) to the disproportionation reactor (126).

12. A system for the vapor phase synthesis of trisilylamine, comprising: (a) a reaction vessel (2), the reaction vessel having a top (7), a bottom (9) and a side wall (15) having an inner surface (21), the side wall (15) connecting the top (7) and the bottom (9), the reaction vessel (2) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) are positioned at or near the top (7) of the reaction vessel (2) and are configured to inject the ammonia and the monohalosilane into the reaction vessel (2) substantially vertically downward from the top (7) of the reaction vessel (2); (b) one or more baffles (32) having a peripheral edge (33), the one or more baffles (32) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32) and a separation zone (5) extending to the bottom of the reaction vessel (2) below the one or more baffles (32); (c) the one or more guide plates (32) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); (d) one or more turbulence inducing mixing structures (60, 70), said one or more turbulence inducing mixing structures being positioned in said reaction zone (3); as well as (e) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

13. The system of claim 12, wherein the one or more turbulence inducing mixing structures (60, 70) are selected from the group consisting of one or more mechanical agitators (60) and one or more static mixers (70).

14. The system of claim 13, wherein the one or more mechanical stirrers (60) are selected from the group consisting of a motor-driven impeller and a magnetic stirrer.

15. A system according to claim 13, wherein the one or more static mixers (70) are selected from the group consisting of porous ceramic materials, porous steel mesh materials and similar materials, and the one or more static mixers (70) are supported by a bracket, which is selected from the group consisting of two or more suspension support brackets (28, 30) connected at or near the top (7) of the reaction vessel (2) and two or more local support brackets (92) connected to the inner surface (21) of the side wall (15).

16. The system of claim 12, further comprising a disproportionation unit (101), the disproportionation unit comprising a distillation column (120) fluidly connected to a condensate trap (51) via a feed conduit (122), the condensate trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2), a disproportionation reactor (126), a condenser (132), and a liquid reservoir (136), the distillation column (120) fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142). ), the TSA-rich stream conduit is used to guide the TSA-rich stream to mix with TSA in the product conduit (36), the disproportionation unit (126) has a disproportionation product conduit (128) and a conduit (130) for guiding ammonia and volatiles to the condenser (132), the condenser (132) has a conduit (134) for guiding DSA liquid to the reservoir (136), and the reservoir (136) has a recirculation conduit (140) and a recirculation pump (138) for guiding DSA liquid from the reservoir (136) to the disproportionation reactor (126).

17. A system for the vapor phase synthesis of trisilylamine, comprising: (a) a cyclonic reaction vessel (2), the cyclonic reaction vessel having a top (7), a bottom (9), a tapered sidewall segment (80), a tangential feed chamber (82) and a generally cylindrical sidewall segment (84), the tapered sidewall segment (80) connecting the generally cylindrical sidewall segment (84) and the bottom (9), the tangential feed chamber (82) comprising a first gas inlet (11) and a second gas inlet (13) for gaseous reactants ammonia and monohalosilane and a third gas inlet (17) for an inert gas, wherein at least the first gas inlet and the second gas inlet (11, 13) and the tangential feed chamber (82) are configured to inject the ammonia and the monohalosilane substantially horizontally and tangentially into the generally cylindrical segment (84) and then into the tapered sidewall segment (80); (b) one or more baffles (32C) having a peripheral edge (33), the one or more baffles (32C) being positioned substantially horizontally at a position in the reaction vessel (2) to define a reaction zone (3) extending to the top (7) of the reaction vessel (2) above the one or more baffles (32C) and a separation zone (5) extending to the bottom (9) of the reaction vessel (2) below the one or more baffles (32C); (c) the one or more guide plates (32C) are positioned in the reaction vessel (2) such that a gap (34) exists between the peripheral edge (33) and the inner surface (21) of the reaction vessel (2); and (d) a reaction product collecting conduit (36) having an inlet end (38) positioned in the separation zone (5), wherein the reaction product comprises trisilylamine.

18. The system of claim 17, comprising a monohalosilane purification subsystem, the monohalosilane purification subsystem comprising: a first separator (102) configured to receive an impure monohalosilane stream (4A) and produce a silane and lighter compound stream (108) and an enriched monohalosilane stream (106), A second separator (104) is configured to receive the enriched monohalosilane stream (106) and produce a reactor feed monohalosilane stream (16) and a polysilane and heavier stream (112).

19. The system of claim 17, comprising a fluorine or fluorine plasma source (94) fluidly connected to the reaction vessel (2), the fluorine or fluorine plasma being suitable for cleaning the reaction vessel (2), the system further comprising a conduit for directing a clean exhaust stream to an exhaust or waste treatment system (90).

20. The system of claim 17, further comprising a disproportionation unit (101), the disproportionation unit comprising a distillation column (120) fluidly connected to a condensate trap (51) via a feed conduit (122), the condensate trap (51) fluidly connected to the separation zone (5) at or near the bottom (9) of the reaction vessel (2), a disproportionation reactor (126), a condenser (132), and a liquid reservoir (136), the distillation column (120) fluidly connected to the disproportionation reactor (126) via a conduit (124), and a TSA-rich stream conduit (142). ), the TSA-rich stream conduit is used to guide the TSA-rich stream to mix with TSA in the product conduit (36), the disproportionation unit (126) has a disproportionation product conduit (128) and a conduit (130) for guiding ammonia and volatiles to the condenser (132), the condenser (132) has a conduit (134) for guiding DSA liquid to the reservoir (136), and the reservoir (136) has a recirculation conduit (140) and a recirculation pump (138) for guiding DSA liquid from the reservoir (136) to the disproportionation reactor (126).

21. A method for preparing trisilylamine using the system according to claim 1.

22. A method for preparing trisilylamine using the system according to claim 12.

23. A method for preparing trisilylamine using the system according to claim 17.

24. A method comprising: a) passing gaseous ammonia and gaseous monohalosilane under pressure downwardly and substantially vertically toward A separation device in a reaction vessel as defined in claim 1 or 12 is fed into the reaction vessel, wherein the separation device is selected from one or more baffles positioned in the reaction vessel as defined in claim 1 or 12; b) separating ammonium chloride solid from gaseous silylamine product in the reaction vessel by using the separation device and the gap between the separation device and the inner surface of the reaction vessel; and c) collecting the gaseous silylamine product.

25. A method comprising: a) feeding gaseous ammonia and gaseous monohalosilane under pressure downwardly and substantially vertically into a reaction vessel as defined in claim 1 or 12 towards and through one or more turbulence inducing mixing structures as defined in any one of claims 12 to 15; b) causing at least some of the ammonium chloride solids to deposit on the interior surfaces of the reaction vessel while forming a gaseous silylamine product; and c) collecting the gaseous silylamine product.

26. The method of claim 25 comprising separating ammonium chloride solid from gaseous silylamine product in the reaction vessel by using a separation device and a gap between the separation device and the inner surface of the reaction vessel, wherein the separation device is selected from one or more baffles positioned in the reaction vessel as defined in claims 1 or 12.

27. A method comprising: a) injecting ammonia and monohalosilane substantially horizontally and tangentially into a generally cylindrical sidewall segment of a cyclonic reaction vessel as defined in claim 17; b) causing the ammonia and monohalosilane to flow into a tapered sidewall segment of the reaction vessel connected to the generally cylindrical segment toward a separation device in the reaction vessel, wherein the separation device is selected from one or more baffles positioned in the reaction vessel as defined in claim 17; c) separating ammonium chloride solid from gaseous silylamine product in the reaction vessel by using the separation device and the gap between the separation device and the inner surface of the reaction vessel; and d) collecting the gaseous silylamine product.

Images