System and method for purifying hexachlorodisilane composition

Abstract

The present disclosure provides a system for purifying a hexachlorodisilane (HCDS) composition, the system including a storage unit configured to store a HCDS composition including impurities, a circulation pump configured to circulate the HCDS composition along a closed circulation loop, an adsorption purifier disposed in the closed circulation loop, the adsorption purifier including an adsorbent and configured to, in a first operating state, selectively adsorb impurities included in the HCDS composition and allow HCDS to pass therethrough, and a filter disposed at an outlet side of the adsorption purifier and configured to, in the first operating state, filter contamination included in the HCDS composition that has passed through the purifier.

Description

Docket No. AUV0001 WO1SYSTEM AND METHOD FOR PURIFYING HEXACHLORODISILANE COMPOSITION CROSS REFERENCE TO RELATED APPLICATION

[0001] The present Application for Patent claims priority to and benefit of U.S. Patent Application No. 63 / 719,820 filed November 13, 2024, which is hereby expressly incorporated by reference herein in its entirety.Technical Field

[0002] The present disclosure relates to a system and a method for purifying a hexachlorodisilane (HCDS) composition, which remove impurities from a composition including HCDS.Background

[0003] Hexachlorodisilane (HCDS, Si2Cle) serves as a silicon precursor for thin film deposition in semiconductor manufacturing. HCDS is purified to a purity of 99.9 % or more through distillation before being sold to fabs. For example, a purified HCDS product may be obtained by feeding an HCDS composition including impurities to a multi-stage distillation column, removing low-boiling components corresponding to impurities at the top, and recovering HCDS at the bottom or as a middle cut. During distillation, HCDS is continuously vaporized / condensed. Under these conditions, small amounts of trichlorosilane (TCS) and tetrachlorosilane (STC) are generated through decomposition of HCDS.Si2Cl6SiHCf (TCS, trichlorosilane) + SiCU (STC, tetrachlorosilane)This decomposition occurs inherently regardless of distillation conditions (temperature, pressure, number of stages in the distillation column, etc.). Thus, HCDS products obtained through distillation contain trace amounts of TCS and STC. Due to this mechanism, purification using distillation alone is insufficient to completely remove impurities from the HCDS product. There is therefore a recognized need to develop alternative separation methods for removing TCS and STC from HCDS products.Disclosure of InventionTechnical Problem

[0004] An embodiment of the present disclosure provides a system and a method for purifying hexachlorodisilane (HCDS) to produce a HCDS product purified to electronics-grade purity by removing trichlorosilane (TCS) and tetrachlorosilane (STC) from a HCDS composition obtained through distillation.

[0005] The objects of the present disclosure are not limited to those described above; additional objects and advantages of the present disclosure will become apparent from theDocket No. AUV0001 WO2following description, and will become more apparent from embodiments of the present disclosure. Furthermore, the objects and advantages of the present disclosure may be realized through the means recited in the claims and combinations thereof.Solution to Problem

[0006] According to one aspect of the present disclosure, a system for purifying a hexachlorodisilane (HCDS) composition includes: a storage unit configured to store a HCDS composition including impurities; a circulation pump configured to circulate the HCDS composition along a closed circulation loop; an adsorption purifier disposed in the closed circulation loop, the adsorption purifier including an adsorbent and configured to, in a first operating state, selectively adsorb the impurities included in the HCDS composition and allow HCDS to pass therethrough; and a filter disposed at an outlet side of the adsorption purifier and configured to, in the first operating state, filter contamination included in the HCDS composition that has passed through the purifier, wherein the impurities are at least one of trichlorosilane (TCS) and tetrachlorosilane (STC).

[0007] Here, the adsorption purifier includes: a body including an inlet port for introducing the HCDS composition and an outlet port for discharging the HCDS composition; and a first screen and a second screen, disposed inside the body to define an adsorbent filling zone for filling with the adsorbent, wherein the first screen and the second screen are configured to allow the HCDS composition to pass therethrough while preventing the adsorbent disposed in the adsorbent filling zone from exiting.

[0008] Here, the adsorption purifier further includes a heater jacket wrapping around at least a part of an outer circumferential surface of the body and configured to apply heat to the adsorbent in a second operating state.

[0009] Here, the system further includes a gas supplying unit disposed at an inlet side of the adsorption purifier and configured to, in the second operating state, heat an inert gas and supply the heated inert gas to the adsorption purifier.

[0010] Here, the system further includes an exhaust unit disposed at an outlet side of the adsorption purifier and configured to, in the second operating state, extract the inert gas that has passed through the adsorption purifier to lower an internal pressure of the adsorption purifier, wherein the gas supplying unit is configured to operate in conjunction with the exhaust unit.

[0011] Here, the adsorbent includes pellets or a powder including pores on a surface or in an interior thereof.

[0012] Here, a size of the pores of the adsorbent is in a range of 5 A to 8 A.Docket No. AUV0001 WO3

[0013] Here, the adsorbent includes a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 50 to 300.

[0014] Here, the adsorbent includes a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 100 to 300.

[0015] According to another aspect of the present disclosure, a method for purifying a hexachlorodisilane (HCDS) composition using the above-described system includes: activating the adsorbent by the controller controlling the heat jacket to heat the adsorption purifier to a first temperature, the controller controlling the gas supplying unit to supply a heated inert gas to the adsorption purifier, and the controller controlling the exhaust unit to extract the inert gas that has passed through the adsorption purifier; obtaining a purified HCDS product from which impurities are removed by the controller controlling the circulation pump to supply the HCDS composition from the storage unit to the adsorption purifier and the filter; and after purifying the HCDS composition, regenerating the adsorbent by the controller controlling the heat jacket to heat the adsorption purifier to a second temperature, the controller controlling the gas supplying unit to supply the heated inert gas to the adsorption purifier, and the controller controlling the exhaust unit to extract the inert gas that has passed through the adsorption purifier.

[0016] Here, the method further includes, subsequent to the activation of the adsorbent, passivating the adsorbent by the controller controlling the heat jacket to heat the adsorption purifier to a third temperature, the controller controlling the gas supplying unit to supply a heated passivation gas to the adsorption purifier, and the controller controlling the exhaust unit to extract the passivation gas that has passed through the adsorption purifier.

[0017] Here, the third temperature is lower than the first temperature and the second temperature.

[0018] Here, the passivation gas includes a chlorosilane gas.

[0019] Further aspects, features, and advantages of the present disclosure will be apparent from the following drawings, claims, and detailed description of the disclosure.Advantageous Effects of Invention

[0020] The present disclosure provides a purification system and method using an adsorbent to selectively remove impurities in a hexachlorodisilane (HCDS) product that cannot be resolved by distillation alone, thereby offering the advantage of reliably producing a HCDS product with higher purity.

[0021] Furthermore, a HCDS product with high purity produced according to the present disclosure can be used in semiconductor manufacturing processes, such as chemical vaporDocket No. AUV0001 WO4deposition (CVD) and atomic layer deposition (ALD), thereby offering the advantage of reducing defects caused by impurities.

[0022] The advantages of the present disclosure are not limited to those mentioned above, and other unmentioned effects can be clearly understood by one of ordinary skill in the art from the following description.Brief Description of Drawings

[0023] FIG. 1 is a process diagram illustrating a system for purifying a hexachlorodisilane composition according to an embodiment of the present disclosure.

[0024] FIG. 2 is a simplified diagram illustrating an adsorption purifier and an adsorbent according to an embodiment of the present disclosure.

[0025] FIG. 3 is a flowchart illustrating a method for purifying a hexachlorodisilane composition according to an embodiment of the present disclosure.

[0026] FIG. 4A is a diagram illustrating step 310 of FIG. 3 in the system of FIG. 1.

[0027] FIG. 4B is a diagram illustrating step 320 of FIG. 3 in the system of FIG. 1.

[0028] FIG. 4C is a diagram illustrating step 330 of FIG. 3 in the system of FIG. 1.

[0029] FIG. 5 is a flowchart illustrating a method for purifying a hexachlorodisilane composition according to another embodiment of the present disclosure.

[0030] FIG. 6 is a diagram illustrating step 315 of FIG. 5 in the system of FIG. 1.Modes of the Invention

[0031] The advantages and features of the present disclosure, along with methods for achieving them, will become apparent from the detailed description of embodiments provided below with reference to the accompanying drawings. However, the present disclosure is not limited to the described embodiments and may be implemented in various forms, encompassing all modifications, equivalents, and substitutes within the spirit and technical scope of the present disclosure. The embodiments described below are provided to complete the disclosure and to fully convey the scope of the disclosure to those skilled in the art. In the following description, detailed explanations of related known technologies will be omitted when such descriptions might obscure the essence of the present disclosure.

[0032] The terms used in the present application are used only to describe specific embodiments and are not intended to limit the present disclosure.

[0033] A singular expression includes a plural expression unless the context clearly indicates otherwise.

[0034] In the present application, terms such as "comprise", "include", or "have" are intended to designate the presence of a described feature, number, step, operation, component,Docket No. AUV0001 WO5part, or a combination thereof, and should be understood not to preclude in advance the presence or addition of one or more other features, numbers, steps, operations, components, parts, or a combination thereof.

[0035] In the present disclosure, terms such as "first," "second," and the like may be used to describe various components, but the components should not be limited by such terms. These terms are used only for the purpose of distinguishing one component from another component.

[0036] In the present disclosure, an "inlet side" and an "outlet side" are defined with respect to a material transport path, wherein for each component, the portion into which a material is introduced is defined as the inlet side, and the portion from which the material is discharged is defined as the outlet side.

[0037] In the present disclosure, the term hexachlorodisilane refers to a compound represented by the chemical formula Si2Cle, and is used herein with the same meaning as HCDS.

[0038] In the present disclosure, the term tetrachlorosilane refers to a compound represented by the chemical formula SiCh, and is used herein with the same meaning as silicon tetrachloride or STC.

[0039] In the present disclosure, the term trichlorosilane refers to a compound represented by the chemical formula SiHCk, and is used herein with the same meaning as TCS.

[0040] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. In the description with reference to the accompanying drawings, identical or corresponding components are assigned the same reference numerals, and redundant descriptions thereof will be omitted.

[0041] FIG. 1 is a process diagram illustrating a system 100 for purifying a hexachlorodisilane (hereinafter, HCDS) composition according to an embodiment of the present disclosure (hereinafter, system 100).

[0042] The system 100 may include a storage unit 110, a fluid circulation device 120, a purifier 130, a filter 140, and a controller 170. Furthermore, the system 100 may further include a gas supplying unit 150 and an exhaust unit 160. At least one of the storage unit 110, the fluid circulation device 120, and the filter 140 may be included in the system 100. At least one of the purifier 130, the gas supplying unit 150 disposed at an inlet side of the purifier 130, and the exhaust unit 160 disposed at an outlet side of the purifier 130 may be included in the system 100. For example, a plurality of purifiers 130 may be provided between the gas supplying unit 150 and the exhaust unit 160. As another example, the gas supplying unit 150, the purifier 130, and the exhaust unit 160 may form one group, and a plurality of the groups may be provided in the system 100.Docket No. AUV0001 WO6

[0043] The system 100 is designed as a closed circulation loop L which connects the storage unit 110, the fluid circulation device 120, the purifier 130, and the filter 140 in sequence and then returns to the storage unit 110. The material stored in the storage unit 110 of the system 100 may be circulated through the closed circulation loop L of the system 100 and stored again in the storage unit 110. To this end, the respective components may be connected by a main pipe (not shown). The material transport path P (hereinafter, flow path P) is defined only in a direction that returns to the storage unit 110 from the storage unit 110 via the purifier 130 and the filter 140. Meanwhile, to prevent backflow of the material moving along the flow path P, the system 100 may further include valves and backflow prevention structures that are not shown in the drawings.

[0044] The storage unit 110 stores the liquid HCDS composition obtained through distillation. Here, the HCDS composition may include about 99 % or more of HCDS and about 1 % or less of impurities. Here, the impurities may include at least one of trichlorosilane (hereinafter, TCS) and tetrachlorosilane (hereinafter, STC), or may be at least one of TCS and STC. Furthermore, the storage unit 110 stores the purified HCDS product after the HCDS composition has been circulated through the system 100. Here, the HCDS product includes about 99.80 % or more of HCDS. The storage unit 110 may be a vessel for storing a liquid material including HCDS. The storage unit 110 may include a container, a tank, a drum, or other suitable types of vessels.

[0045] The fluid circulation device 120 is configured to circulate the HCDS composition stored in the storage unit 110 along the closed circulation loop L. The fluid circulation device 120 may be a circulation pump, a centrifugal pump, a gear pump, a diaphragm pump, a piston pump, a compressor, a blower, a gravity-fed system, or a gas-driven displacement system using a pressure differential. Hereinafter, a case in which the fluid circulation device 120 is a circulation pump 120a will be described as an example.

[0046] An operation of the circulation pump 120a may be controlled by the controller 170. The circulation pump 120a draws in the HCDS composition stored in the storage unit 110 and propels the HCDS composition in a direction of the purifier 130 and the filter 140 using a pressure differential. The HCDS composition passes through the purifier 130 and the filter 140 and flows back into the storage unit 110. The circulation pump 120a causes the HCDS composition to circulate along the flow path P of the closed circulation loop L.

[0047] In the present disclosure, the term "cycle" refers to performing one time a series of circulation processes in which the HCDS composition stored in the storage unit 110 returns to the storage unit 110 after passing through the purifier 130 and the filter 140 along the flow path P by the driving of the fluid circulation device 120.Docket No. AUV0001 WO7

[0048] In the present disclosure, the term "batch" refers to a unit of work for completing the purification of the entire HCDS composition stored in the storage unit 110 by repeating a plurality of cycles. Accordingly, one batch may be composed of a plurality of cycles.

[0049] The purifier 130 is disposed at an outlet side of the fluid circulation device 120 with respect to the flow path P. The purifier 130 is disposed at an outlet side of the storage unit 110 and at an inlet side of the filter 140. The purifier 130 may be an adsorption purifier 130a. The adsorption purifier 130a removes impurities included in the HCDS composition by using an adsorbent. The purifier 130 further includes a heat jacket 135 surrounding an outer circumferential surface thereof. A specific configuration of the adsorption purifier 130a will be described below with reference to FIG. 2.

[0050] The filter 140 is disposed at an outlet side of the purifier 130 with respect to the flow path P. The filter 140 is disposed at the outlet side of the purifier 130 and in a final step before the HCDS composition returns to the storage unit 110. The filter 140 serves to prevent contamination of the HCDS composition purified in the purifier 130. The filter 140 may be a micro filter, a membrane filter, a cartridge filter, a bag filter, an adsorption cartridge, an ionexchange resin unit, an activated carbon filter, or a multi-layer filter medium. In an embodiment, the filter 140 may be a microfilter with a filter rating of less than about 0.1 micrometers. Because the microfilter is capable of removing particles having a diameter equal to or greater than about 0.1 micrometers (100 nanometers) without allowing them to pass through, the microfilter may effectively remove fine powder, adsorbent fines, and fine solid impurities included in the purified HCDS composition to prevent contamination of the purified HCDS composition.

[0051] The controller 170 controls each component included in the system 100 to circulate the HCDS composition stored in the storage unit 110 along the closed circulation loop L of the system 100, thereby obtaining purified HCDS. The controller 170 may include a processor, and the processor may be implemented using a hardware configuration of at least one of application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), field programmable gate arrays (FPGAs), controllers, micro-controllers, microprocessors, and other electrical units for performing other functions.

[0052] The gas supplying unit 150 is disposed at an inlet side of the purifier 130. The gas supplying unit 150 may supply an inert gas for activation and regeneration of the adsorbent in the adsorption purifier 130a to the adsorption purifier 130a. Furthermore, the gas supplying unit 150 may supply a passivation gas for passivation of the adsorbent in the purifier 130 to the adsorption purifier 130a. The gas supplying unit 150 may include a gas line 151, a gas heater 152,Docket No. AUV0001 WO8a first valve 153, a first-1 valve 154-1, and a first-2 valve 154-2. A configuration included in the gas supplying unit 150 may be controlled by the controller 170.

[0053] The gas line 151 may be selectively connected to a gas tank / gas cylinder (not shown) for supplying an inert gas or a gas tank / gas cylinder (not shown) for supplying a passivation gas. The inert gas may be nitrogen gas or argon gas. The passivation gas may be a chlorosilane-based gas, and for example, the passivation gas may be at least one of trichlorosilane (TCS, SiHCf), tetrachlorosilane (STC, SiCh), dichlorosilane (DCS, SifbCh), and mixtures thereof.

[0054] The gas heater 152 is a device that is connected to the gas line 151 and heats the gas supplied from the gas line 151. The gas heater 152 heats the gas required for adsorbent activation, regeneration, and passivation to a high temperature. If a cold gas is directly injected, the cold gas may be condensed; however, pre-heating the gas to a set temperature before introducing it into the adsorption purifier 130a ensures a stable operation. The gas heater 152 may heat the gas to 100 degrees Celsius or higher or 200 degrees Celsius or higher according to use conditions.

[0055] The first valve 153 is a backflow prevention valve that is connected to the gas line 151 and disposed between the gas heater 152 and a main pipe in which the flow path P flows, wherein the first valve 153 allows gas to flow only in a direction toward the main pipe and prevents back flow. The first valve 153 may be a regular valve, check valve or block valve.

[0056] The first- 1 valve 154-1 and the first-2 valve 154-2 are block valves for general opening / closing, are connected to the main pipe, and control a flow of a fluid in the flow path P to be ON (open) / OFF (closed). The first- 1 valve 154-1 mainly blocks or opens a flow of the HCDS composition to the flow path P, and the first-2 valve 154-2 blocks or opens an inflow of the HCDS composition to an inlet of the purifier 130. The two gate valves are for double isolation, which facilitates maintenance and repair of the system 100 and enhances the safety of the system 100.

[0057] The exhaust unit 160 is disposed at an outlet side of the purifier 130. The exhaust unit 160 performs an exhaust of moisture and residual gas during activation and regeneration of the adsorbent in the adsorption purifier 130a. That is, the exhaust unit 160 is configured to extract the inert gas that has passed through the adsorption purifier 130a to lower an internal pressure of the adsorption purifier 130a. Furthermore, the exhaust unit 160 may perform the exhaust of moisture and residual gas during passivation of the adsorbent in the adsorption purifier 130a. The exhaust unit 160 may include a vacuum unit 161, a second valve 163, a second- 1 valve 164-1, and a second-2 valve 164-2. A configuration included in the exhaust unit 160 may be controlled by the controller 170. Furthermore, the controller 170 controls the gas supplying unit 150 and theDocket No. AUV0001 WO9exhaust unit 160 to operate in conjunction with each other.

[0058] The vacuum unit 161 is connected to an exhaust line branched from a main pipe between the purifier 130 and the filter 140. The vacuum unit 161 evacuates the purifier 130 to form a vacuum, and exhausts and removes moisture, impurities, and residual gas inside the purifier 130 during adsorbent activation, regeneration, and passivation processes.

[0059] The second valve 163 is a backflow prevention valve that is connected to the exhaust line and disposed between the vacuum unit 161 and a main pipe in which the flow path P flows, wherein the second valve 163 allows the vacuum unit 161 to draw in and evacuate the purifier 130 while preventing a reverse flow. The second valve 163 may be a regular valve, check valve or block valve.

[0060] The second- 1 valve 164-1 and the second-2 valve 164-2 are block valves for general opening / closing, are connected to the main pipe, and control a flow of a fluid in the flow path P to be ON (open) / OFF (closed). The second- 1 valve 164-1 blocks or opens an outlet of the purifier 130, and the second-2 valve 164-2 blocks or opens an inlet of the filter 140. The two gate valves are for double isolation, which facilitates maintenance and repair of the system 100 and enhances the safety of the system 100.

[0061] The controller 170 may control the second- 1 valve 164-1 and the second-2 valve 164-2 in conjunction with the first-1 valve 154-1 and the first-2 valve 154-2. The controller 170 controlling the valves will be described in detail with reference to FIG. 3.

[0062] FIG. 2 is a simplified diagram illustrating an adsorption purifier 130a and an adsorbent 1301 according to an embodiment of the present disclosure.

[0063] Referring to FIG. 2, the adsorption purifier 130a includes a body 134, an adsorbent bed 133 inside the body 134, and a heat jacket 135 outside the body 134.

[0064] The body 134 accommodates the adsorbent bed 133 and defines a space in which the HCDS composition is purified by passing through the adsorbent bed 133. The body 134 includes an inlet 131 through which the HCDS composition is introduced in a direction of the flow path P, and an outlet 132 through which the HCDS composition is discharged in the direction of the flow path P. Furthermore, the body 134 may separately provide temperature and pressure measurement ports (not shown).

[0065] The body 134 may be in a shape of a cylindrical column, and may be a cylindrical horizontal column or a cylindrical vertical column. The inlet 131 and the outlet 132 may be disposed at a top portion, a bottom portion, or both end portions of the body 134 according to the direction of the flow path. A ratio of a height (H) to a diameter (D) of the body 134 may be in a range of about 1 to 10. A material of the body 134 may be a metal material having strong corrosionDocket No. AUV0001 WO10resistance in consideration of HCDS and chlorosilane, and may be made of low-carbon stainless steel (Stainless Steel 316L, SS316L), a nickel-molybdenum-chromium alloy (Hastelloy C-22 / C-276), or a nickel-copper alloy (Monel). An internal surface roughness of the body 134 may be about Ra (Roughness Average) < 0.5 micrometers to minimize contamination and adsorption.

[0066] The inlet 131 of the body 134 may be disposed at an outlet side of the fluid circulation device 120, and may be connected to a top portion of the body 134 (during downflow operation) or a first side surface facing a direction of the flow path. The outlet 132 of the body 134 may be disposed at an inlet side of the filter 140, and may be connected to a bottom portion of the body 134 (during downflow operation) or a second side surface opposite the first side surface.

[0067] The heat jacket 135 is provided to surround an outside of the body 134 and applies heat to the adsorbent bed 133 and the adsorbent 1301 inside the body 134. The heat jacket 135 is provided to wrap around at least apart of an outer circumference of the cylindrical body 134. The heat jacket 135 may be a cylindrical structure disposed concentrically with the body 134. The heat jacket 135 may be an electric band jacket or a heat medium (oil or steam) jacket. When the heat jacket 135 is a heat medium jacket, the heat jacket 135 forms a heat medium flow space between an outer wall of the body 134 and the heat jacket 135, and may include a heat medium inlet for introducing the heat medium into the heat medium flow space and a heat medium outlet for discharging the heat medium from the heat medium flow space.

[0068] Heating and cooling of the heat jacket 135 may be controlled by the controller 170. During activation and regeneration of the adsorbent, the controller 170 controls the heat jacket 135 to heat the interior of the purifier 130 to a high temperature of about 200 degrees Celsius or higher. Furthermore, during the passivation of the adsorbent 1301, the controller 170 controls the heat jacket 135 to heat the interior of the purifier 130 to a high temperature of about 100 degrees Celsius or higher.

[0069] The adsorbent bed 133 includes a first screen 133a and a second screen 133b, which are disposed inside the body 134 to be in close contact with an entire circumferential direction thereof with a diameter identical to an inner diameter of the body 134 to define an adsorbent filling zone 133z, and an adsorbent filled in the adsorbent filling zone 133z.

[0070] The first screen 133a may be disposed at a side of the inlet 131, and the second screen 133b may be disposed at a side of the outlet 132. The first screen 133a and the second screen 133b define the adsorbent filling zone 133z, and are configured to allow the HCDS composition to pass therethrough while preventing the adsorbent disposed in the adsorbent filling zone from exiting. The first screen 133a and the second screen 133b may be made of the sameDocket No. AUV0001 WO11material as the body 134. Each of the first screen 133a and the second screen 133b may have a structure in which a wire mesh or a sintered metal filter is stacked on a perforated support plate.

[0071] The adsorbent filling zone 133z may occupy about 60 % to 80 % of an internal volume of the body 134. A remaining space of the body 134, excluding the adsorbent filling zone 133z, may be a free space for fluid expansion or a space for ensuring a uniform flow. The adsorbent 1301 fills about 50 % to 90 % of the adsorbent filling zone 133z. Overfilling the adsorbent 1301 to more than 90 % results in an increased pressure loss and the occurrence of channeling. If the amount of the adsorbent 1301 is less than 50 %, the purification efficiency is reduced due to an insufficient contact time between the HCDS composition and the adsorbent.

[0072] The adsorbent 1301 selectively adsorbs impurities included in the HCDS composition. In detail, the adsorbent 1301 substantially allows HCDS to pass therethrough, but adsorbs TCS and STC. The adsorbent 1301 may be a pellet or a powder that includes effective pores on a surface or in an interior thereof.

[0073] The adsorbent 1301 is characterized in that a size of the effective pores is in a range of about 5 A to 8 A. If the size of the effective pores is smaller than 5 A, TCS and STC are prevented from entering the effective pores, and thus the removal of impurities is not achieved. If the size of the effective pores is larger than 8 A, HCDS is also adsorbed, thereby negating the purification effect. Therefore, the size of the effective pores within the corresponding numerical range is a unique parameter that allows for the most effective removal of TCS and STC from the HCDS composition.

[0074] The adsorbent 1301 may be a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 50 to 300. Preferably, the adsorbent 1301 may be a crystalline aluminosilicate zeolite in which a ratio of Si atoms to Al atoms is 100 to 300. In the crystalline aluminosilicate zeolite, a strength and a number of active sites may vary depending on the Si / Al ratio. If the Si / Al ratio is less than 100, the crystalline aluminosilicate zeolite exhibits a higher density of active sites and stronger acidity, creating a risk of side reactions between the crystalline aluminosilicate zeolite and HCDS. If the Si / Al ratio exceeds 300, the hydrophobic property of the crystalline aluminosilicate zeolite increases while the number of active sites decreases, leading to a reduced adsorption capacity and a lower adsorption efficiency for TCS and STC.

[0075] The adsorbent 1301 is used for purifying the HCDS composition after being activated. The activation of the adsorbent is a process of normalizing an adsorption function of the adsorbent 1301 by removing moisture and volatile components included in the adsorbent 1301. The adsorbent 1301 is activated by being purged with an inert gas at a high temperature of aboutDocket No. AUV0001 WO12200 degrees Celsius or higher under vacuum.

[0076] The adsorbent 1301 may be reused for purifying the HCDS composition after undergoing a regeneration process. The regeneration of the adsorbent is a process of restoring the adsorption function by removing impurities from the adsorbent saturated with the impurities. The adsorbent 1301 is regenerated by being purged with an inert gas at a high temperature of about 200 degrees Celsius or higher under vacuum.

[0077] In detail, in the activation and regeneration processes of the adsorbent, the controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 200 degrees Celsius or higher. The controller 170 controls the gas supplying unit 150 to purge with an inert gas to remove impurities in the adsorbent bed 133, and controls the exhaust unit 160 to evacuate the purifier 130 to remove residual impurities under vacuum.

[0078] In an alternative embodiment, the adsorbent 1301 may be passivated after being activated. The passivation of the adsorbent is a process of reducing a reactivity between the adsorbent 1301 and HCDS by exposing active sites on a surface of the adsorbent 1301 to a chlorosilane-based gas. The adsorbent 1301 is passivated by being purged with a chlorosilane-based gas at a high temperature of about 100 degrees Celsius or higher under vacuum. In this process, Lewis acid sites inside the adsorbent 1301 are blocked to prevent a side reaction between HCDS and the adsorbent 1301 during the purification process of the HCDS composition. The passivation of the adsorbent may be performed at a lower temperature than the activation and regeneration of the adsorbent.

[0079] In detail, the controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 100 degrees Celsius or higher. The controller 170 controls the gas supplying unit 150 to purge with a passivation gas to passivate the adsorbent. After the adsorbent is passivated, the controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 200 degrees Celsius or higher, and controls the exhaust unit 160 to evacuate the purifier 130 to remove residual gas under vacuum.

[0080] FIG. 3 is a flowchart illustrating a method for purifying a hexachlorodisilane composition according to an embodiment of the present disclosure. FIG. 4A is a diagram illustrating step 310 of FIG. 3 in the system 100 of FIG. 1. FIG. 4B is a diagram illustrating step 320 of FIG. 3 in the system 100 of FIG. 1. FIG. 4C is a diagram illustrating step 330 of FIG. 3 in the system 100 of FIG. 1. Each step may be performed by the controller 170 controlling the components of the system 100.

[0081] Referring to FIG. 3, instep 300 (S300), the storage unit 110 stores a liquid HCDS composition obtained through distillation. Here, the HCDS composition may include about 99 %Docket No. AUV0001 WO13or more of HCDS and about 1 % or less of impurities. Here, the impurities may include at least one of trichlorosilane (TCS) and tetrachlorosilane (STC).

[0082] Referring to FIGS. 3 and 4A, in step 310 (S310), the adsorbent is activated. The activation of the adsorbent is a process of normalizing an adsorption function of the adsorbent by removing moisture and volatile components included in the adsorbent. The activation of the adsorbent is performed by purging with an inert gas (IS) at a high temperature of about 200 degrees Celsius or higher under vacuum. The activation temperature may be about 200 degrees Celsius or higher, and preferably, may be in a range of about 200 degrees Celsius to about 450 degrees Celsius.

[0083] The controller 170 activates the adsorbent by controlling each configuration of the system 100. The controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 200 degrees Celsius or higher. Furthermore, the controller 170 controls the gas supplying unit 150 to purge with an inert gas (IS) to remove moisture and volatile components in the adsorbent bed 133, and controls the exhaust unit 160 to evacuate the purifier 130 to remove residual moisture and volatile components under vacuum.

[0084] In detail, the controller 170 controls the gas supplying unit 150 to control an inflow of the inert gas (IS) into the purifier 130. The controller 170 controls the gas line 151 and the gas heater 152 to control a supply of the inert gas (IS), which is heated to a predetermined temperature, to the purifier 130. Furthermore, the controller 170 prevents the HCDS composition from being introduced into the purifier 130 by turning a first-1 valve 154-1 OFF (closed), and allows an inert gas (IS) to be introduced into the purifier 130 by turning a first-2 valve 154-2 ON (open). Simultaneously, the controller 170 allows the vacuum unit 161 to evacuate the purifier 130 by turning a second- 1 valve 164-1 ON (open), and blocks a filter 140 from being affected by the evacuation by turning a second-2 valve 164-2 OFF (closed).

[0085] In an embodiment, the activation of the adsorbent may be performed before starting a first cycle. This process is to remove moisture and volatile components included in the adsorbent before performing the first cycle. In another embodiment, the activation of the adsorbent may be performed after each batch is completed. During one batch, the HCDS in the storage unit 110 may be purified by being repeatedly passed through the adsorption purifier 130a in multiple cycles.

[0086] Referring to FIGS. 3 and 4B, in step 320 (S320), the HCDS composition is purified. The HCDS composition stored in the storage unit 110 is stored in the storage unit 110 as a purified HCDS product after passing through the purifier 130 and the filter 140 along the flow path P via the fluid circulation device 120.Docket No. AUV0001 WO14

[0087] The controller 170 controls the fluid circulation device 120 to cause the HCDS composition stored in the storage unit 110 to circulate in the closed circulation loop L along the flow path P. The HCDS composition is purified into an HCDS product by passing through the purifier 130 and then the filter 140, and is then stored in the storage unit 110. At this time, the controller 170 allows the HCDS composition to be introduced into the purifier 130 by turning a first-1 valve 154-1 and a first-2 valve 154-2 ON (open). Meanwhile, the controller 170 prevents gas from being introduced into the purifier 130 by turning an additional gate valve, which is not shown on the gas line 151, OFF (closed). Simultaneously, the controller 170 allows the HCDS composition to be introduced into the purifier 130 by turning a second- 1 valve 164-1 and a second-2 valve 164-2 ON (open). Meanwhile, the controller 170 turns the vacuum unit 161 OFF (closed) so that the purifier 130 is not evacuated.

[0088] The controller 170 may control an operating temperature of the system 100 to be in a range of about 15 degrees Celsius to 20 degrees Celsius and an operating pressure of the system 100 to be in a range of about 10 to 200 kPa(g). If the operating temperature is lower than 15 degrees Celsius, the viscosity of the material may increase or crystallization may occur, which reduces circulation and adsorption efficiency. If the operating temperature is higher than 20 degrees Celsius, thermal decomposition of the material may occur. If the operating pressure is lower than about 10 kPa(g), the risk of vaporization or leakage increases, and if the operating pressure is higher than about 200 kPa(g), the safety of the apparatus may be compromised.

[0089] The purification of the HCDS composition may include one cycle, several cycles, or tens of cycles. The number of cycles may be predetermined, and may be adjusted according to a percentage of impurities included in the HCDS composition.

[0090] The purifier 130 removes TCS and STC included in the HCDS composition by adsorption onto an adsorbent, and the filter 140 filters contamination such as fine powder, adsorbent fines, and fine solid impurities from the HCDS composition that has passed through the purifier 130. The HCDS composition before purification includes about 99 % or more of HCDS and about 1 % or less of impurities, but the HCDS product after purification includes about 99.80 % or more of HCDS and about 0.20 % or less of impurities, and preferably includes about 99.92 % or more of HCDS and about 0.08 % or less of impurities.

[0091] In an optional embodiment, the controller 170 may control the fluid circulation device 120 to adjust a residence time of the HCDS composition in the purifier 130. The controller 170 may adjust the residence time according to a percentage of impurities included in the HCDS composition.Docket No. AUV0001 WO15

[0092] Referring to FIGS. 3 and 4C, in step 330 (S330), the adsorbent is regenerated. The regeneration of the adsorbent is a process of restoring an adsorption function by removing impurities from the adsorbent saturated with the impurities. The adsorbent is regenerated by being purged with an inert gas (IS) at a high temperature of about 200 degrees Celsius or higher under vacuum. The regeneration temperature may be about 200 degrees Celsius or higher, and preferably, may be in a range of about 200 degrees Celsius to about 450 degrees Celsius.

[0093] The controller 170 regenerates the adsorbent by controlling each configuration of the system 100. The controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 200 degrees Celsius or higher. Furthermore, the controller 170 controls the gas supplying unit 150 to purge with an inert gas (IS) to remove impurities in the adsorbent bed 133, and controls the exhaust unit 160 to evacuate the purifier 130 to remove residual impurities under vacuum. Here, the impurities may be STC and TCS.

[0094] In detail, the controller 170 controls the gas supplying unit 150 to control an inflow of the inert gas (IS) into the purifier 130. The controller 170 controls the gas line 151 and the gas heater 152 to control a supply of the inert gas (IS), which is heated to a predetermined temperature, to the purifier 130. Furthermore, the controller 170 prevents the HCDS composition from being introduced into the purifier 130 by turning a first-1 valve 154-1 OFF (closed), and allows the inert gas (IS) to be introduced into the purifier 130 by turning a first-2 valve 154-2 ON (open). Simultaneously, the controller 170 allows the vacuum unit 161 to evacuate the purifier 130 by turning a second- 1 valve 164-1 ON (open), and blocks a filter 140 from being affected by the evacuation by turning a second-2 valve 164-2 OFF (closed).

[0095] In an embodiment, the regeneration of the adsorbent may be performed each time a cycle is completed. In another embodiment, the regeneration of the adsorbent may be performed after each batch is completed.

[0096] Meanwhile, in the present disclosure, a first operating state may be a state in which the controller 170 controls the system to operate in correspondence with the activation of the adsorbent (S310) and the regeneration of the adsorbent (S330). Accordingly, the first operating state may be a case in which an interior of the purifier 130 is in a vacuum and at a high temperature of about 200 degrees Celsius or higher. Furthermore, in the present disclosure, a second operating state may be a state in which the controller 170 controls the system to operate in correspondence with the purification of the HCDS composition (S320). Accordingly, the second operating state may be a case in which an operating temperature of the system 100 is in a range of about 15 degrees Celsius to 20 degrees Celsius and an operating pressure of the system 100 is in a range of about 10 to 200 kPa(g).Docket No. AUV0001 WO16

[0097] Referring back to FIG. 3, after the regeneration of the adsorbent, the purification of the HCDS composition may be performed again.

[0098] FIG. 5 is a flowchart illustrating a method for purifying a hexachlorodisilane composition according to another embodiment of the present disclosure. FIG. 6 is a diagram illustrating step 315 of FIG. 5 in the system 100 of FIG. 1.

[0099] The embodiment of FIG. 5 further includes passivating an adsorbent as compared to the embodiment of FIG. 3. Hereinafter, step 315 (S315) will be described in detail, and for the remaining steps, reference is made to the description of FIG. 3.

[0100] Referring to FIGS. 5 and 6, in step 315 (S315), the activated adsorbent is passivated. The passivation of the adsorbent is a process of reducing a reactivity between the adsorbent and HCDS by exposing active sites on a surface of the adsorbent to a chlorosilane-based gas. In this process, Lewis acid sites inside the adsorbent are blocked to prevent a side reaction between HCDS and the adsorbent during the purification process of the HCDS composition. The adsorbent is passivated by being purged with a chlorosilane-based gas at a high temperature of about 100 degrees Celsius or higher under vacuum. The passivation temperature may be about 100 degrees Celsius or higher, and preferably, may be in a range of about 100 degrees Celsius to about 200 degrees Celsius. The passivation temperature may be lower than the activation and regeneration temperatures.

[0101] The controller 170 passivates the adsorbent by controlling each configuration of the system 100. The controller 170 controls the heat jacket 135 to heat the adsorbent bed 133 to about 100 degrees Celsius or higher. Furthermore, the controller 170 controls the gas supplying unit 150 to purge with a passivation gas (PS) to passivate the adsorbent, and controls the exhaust unit 160 to evacuate the purifier 130 to remove residual gas under vacuum.

[0102] In detail, the controller 170 controls the gas supplying unit 150 to control an inflow of the passivation gas (PS) into the purifier 130. The controller 170 controls the gas line 151 and the gas heater 152 to control a supply of the passivation gas (PS), which is heated to a predetermined temperature, to the purifier 130. Furthermore, the controller 170 prevents the HCDS composition from being introduced into the purifier 130 by turning a first- 1 valve 154-1 OFF (closed), and allows the passivation gas (PS) to be introduced into the purifier 130 by turning a first-2 valve 154-2 ON (open). Simultaneously, the controller 170 allows the vacuum unit 161 to evacuate the purifier 130 by turning a second- 1 valve 164-1 ON (open), and blocks a filter 140 from being affected by the evacuation by turning a second-2 valve 164-2 OFF (closed).

[0103] In an optional embodiment, after passivating the adsorbent, the controller 170 may control the heat jacket 135 to heat the adsorbent bed 133 to about 200 degrees Celsius orDocket No. AUV0001 WO17higher, and may control the exhaust unit 160 to evacuate the purifier 130 to remove residual gas under vacuum.<Example>

[0104] Example was performed by exposing a HCDS composition to an adsorbent under conditions of 15 degrees Celsius and 1 atm (101.325 kPa). Example was performed using labscale equipment in a glove box to prevent moisture contamination. A moisture concentration was controlled to be 1 ppm or less. After HCDS purified through distillation was injected into a sample vial containing an activated adsorbent, the vial was agitated to simulate a flow. Samples were collected over time to evaluate a performance of the adsorbent. As the adsorbent, a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 50 to 300 was used.

[0105] Table 1 presents the results of a gas chromatography analysis providing data on the impurity removal rate versus the exposure time of the HCDS composition to the adsorbent (i.e., the residence time).[Table 1]by the adsorbent, the purity of HCDS in the HCDS composition increases.

[0106] In the specification of the present disclosure (particularly in the claims), the use of the term "the" and similar referential terms may correspond to both the singular and the plural. Furthermore, when a range is described in the present disclosure, it is to be understood that the disclosure includes embodiments applying each individual value within the range (unless otherwise indicated), as if each individual value constituting the range were set forth in the detailed description of the disclosure.

[0107] The recitation of “at least one of A, B and C” should be interpreted as one or more of a group of elements consisting of A, B and C, and should not be interpreted as requiring at least one of each of the listed elements A, B and C, regardless of whether A, B and C are related as categories or otherwise.Docket No. AUV0001 WO18

[0108] Unless an order is explicitly recited or otherwise stated for the steps constituting the method according to the present disclosure, the steps may be performed in any suitable order. The present disclosure is not necessarily limited to the order in which the steps are described. The use of all examples or exemplary terms (for example, and so on) in the present disclosure is merely for the purpose of describing the present disclosure in detail, and the scope of the present disclosure is not limited by such examples or exemplary terms unless limited by the claims. Furthermore, those skilled in the art will understand that various modifications, combinations, and changes may be made according to design conditions and factors within the scope of the appended claims or equivalents thereof.

[0109] Therefore, the spirit of the present disclosure should not be determined as being limited to the embodiments described above, and not only the claims described below but also all ranges that are equivalent to or equivalently changed from these claims shall be considered to belong to the scope of the spirit of the present disclosure.

Claims

Docket No. AUV0001 WO19CLAIMS1. A system for purifying a hexachlorodisilane (HCDS) composition, the system comprising:a storage unit configured to store a HCDS composition including impurities;a circulation pump configured to circulate the HCDS composition along a closed circulation loop;an adsorption purifier disposed in the closed circulation loop, the adsorption purifier including an adsorbent and configured to, in a first operating state, selectively adsorb the impurities included in the HCDS composition and allow HCDS to pass therethrough; anda filter disposed at an outlet side of the adsorption purifier and configured to, in the first operating state, filter contamination included in the HCDS composition that has passed through the purifier,wherein the impurities are at least one of trichlorosilane (TCS) and tetrachlorosilane (STC).

2. The system of claim 1 ,wherein the adsorption purifier comprises:a body including an inlet port for introducing the HCDS composition and an outlet port for discharging the HCDS composition; anda first screen and a second screen, which are disposed inside the body to define an adsorbent filling zone for filling with the adsorbent, wherein the first screen and the second screen are configured to allow the HCDS composition to pass therethrough while preventing the adsorbent disposed in the adsorbent filling zone from exiting.

3. The system of claim 2,wherein the adsorption purifier further comprises:a heater jacket wrapping around at least a part of an outer circumferential surface of the body and configured to apply heat to the adsorbent in a second operating state.

4. The system of claim 3, further comprising a gas supplying unit disposed at an inlet side of the adsorption purifier and configured to, in the second operating state, heat an inert gas and supply the heated inert gas to the adsorption purifier.Docket No. AUV0001 WO205. The system of claim 4, further comprising:an exhaust unit disposed at an outlet side of the adsorption purifier and configured to, in the second operating state, extract the inert gas that has passed through the adsorption purifier to lower an internal pressure of the adsorption purifier,wherein the gas supplying unit is configured to operate in conjunction with the exhaust unit.

6. The system of claim 1 ,wherein the adsorbent comprises pellets or a powder including effective pores on a surface or in an interior thereof.

7. The system of claim 6,wherein a size of the effective pores of the adsorbent is in a range of 5 A to 8 A.

8. The system of claim 1 ,wherein the adsorbent comprises a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 50 to 300.

9. The system of claim 1 ,wherein the adsorbent comprises a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 100 to 300.

10. A method for purifying a hexachlorodisilane (HCDS) composition using the system of claim 5, the method comprising:activating the adsorbent by a controller controlling the heat jacket to heat the adsorption purifier to a first temperature, the controller controlling the gas supplying unit to supply a heated inert gas to the adsorption purifier, and the controller controlling the exhaust unit to extract the inert gas that has passed through the adsorption purifier;obtaining a purified HCDS product from which impurities are removed by the controller controlling the circulation pump to supply the HCDS composition from the storage unit to the adsorption purifier and the filter; andafter purifying the HCDS composition, regenerating the adsorbent by the controller controlling the heat jacket to heat the adsorption purifier to a second temperature, the controller controlling the gas supplying unit to supply the heated inert gas to the adsorption purifier, and theDocket No. AUV0001 WO21controller controlling the exhaust unit to extract the inert gas that has passed through the adsorption purifier.

11. The method of claim 10, further comprising,subsequent to the activation of the adsorbent, passivating the adsorbent by the controller controlling the heat jacket to heat the adsorption purifier to a third temperature, the controller controlling the gas supplying unit to supply a heated passivation gas to the adsorption purifier, and the controller controlling the exhaust unit to extract the passivation gas that has passed through the adsorption purifier.

12. The method of claim 11 ,wherein the third temperature is lower than the first temperature and the second temperature.

13. The method of claim 11 ,wherein the passivation gas comprises a chlorosilane gas.

14. The method of claim 10,wherein the adsorbent comprises pellets or a powder including pores on a surface or in an interior thereof.

15. The method of claim 14,wherein a size of the pores of the adsorbent is in a range of 5 A to 8 A.

16. The method of claim 10,wherein the adsorbent comprises a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 50 to 300.

17. The method of claim 10,wherein the adsorbent comprises a crystalline aluminosilicate zeolite in which a ratio of silicon (Si) atoms to aluminum (Al) atoms is 100 to 300.

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