Process gas recirculation

Abstract

Systems and methods useful for gas reuse thin film deposition apparatuses are described herein. Embodiments of the present disclosure are directed, inter alia, to one or more of separate collection and recycle of one or more gases, such as precursors, reactants, and purge gases.

Description

Technical Field

[0001] Embodiments of the present disclosure belong to the field of gas-phase thin film processing. They particularly relate to gas recirculation in thin film processing. Background Art

[0002] Thin film processing techniques such as chemical vapor deposition, atomic layer deposition, and etching such as atomic layer etching consume large amounts of gases and vapors, including precursors, reactants, and inert gases. This applies to thermal processes and their plasma-enhanced variants.

[0003] Not all precursors are consumed during the thin film process. Therefore, there is an opportunity for precursor recirculation.

[0004] Not all reactants are consumed during thin film processing. Therefore, there is an opportunity for reactant recirculation.

[0005] Inert process gases are essentially not changed by the thin film process. Therefore, there is an opportunity for inert process gas recirculation. Summary of the Invention

[0006] In one embodiment, a system is described herein that includes a reaction chamber; a precursor source including a precursor, the precursor source being operably connected to the reaction chamber via a precursor pipeline, the precursor pipeline being provided with a precursor valve operable to open and close the precursor pipeline; a reactant source including a reactant, the reactant source being operably connected to the reaction chamber via a reactant pipeline, the reactant pipeline being provided with a reactant valve operable to open and close the reactant pipeline; a precursor sidestream pipeline configured and arranged to remove a precursor sidestream from the reaction chamber, the precursor sidestream pipeline being provided with a precursor sidestream valve operable to open and close the precursor sidestream pipeline; a reactant sidestream pipeline configured and arranged to remove a reactant sidestream from the reaction chamber, the reactant sidestream pipeline being provided with a reactant sidestream valve operable to open and close the reactant sidestream pipeline.

[0007] In some embodiments, the system further includes a controller that includes a memory containing computer-readable instructions that, when executed, cause the system to open the precursor pipeline, close the reactant pipeline, open the precursor sidestream pipeline, and close the reactant sidestream pipeline.

[0008] In some embodiments, the system further includes a controller that includes a memory containing computer-readable instructions that, when executed, cause the system to open the reactant pipeline, close the precursor pipeline, open the reactant sidestream pipeline, and close the precursor sidestream pipeline.

[0009] In some embodiments, the system further includes a controller that includes a memory containing computer-readable instructions that, when executed, cause the system to perform a cyclic deposition process. The cyclic deposition process includes a plurality of cycles, and a cycle from the plurality of cycles includes a precursor pulse and a reactant pulse. The precursor pulse includes opening a precursor line, closing a reactant line, opening a precursor bypass line, and closing a reactant bypass line, thereby providing a precursor to the reaction chamber and removing a precursor bypass from the reaction chamber through the precursor bypass line. And the reactant pulse includes opening a reactant line, closing a precursor line, opening a reactant bypass line, and closing a precursor bypass line, thereby providing a reactant to the reaction chamber and removing a reactant bypass from the reaction chamber through the reactant bypass line.

[0010] In some embodiments, the system further includes a purge gas source containing a purge gas. The purge gas source is operably connected to the reaction chamber through a purge gas line, and the purge gas line is provided with one or more purge gas valves operable to open and close the purge gas line.

[0011] In some embodiments, the cyclic deposition process further includes a post-precursor purge and a post-reactant purge. The post-precursor purge is performed after the precursor pulse, and the post-precursor purge includes opening the purge gas line, opening the precursor bypass line, closing the precursor line, closing the reactant line, and closing the reactant bypass line. The post-reactant purge is performed after the reactant pulse, and the post-reactant purge includes opening the purge gas line, opening the reactant bypass line, closing the precursor line, closing the reactant line, and closing the precursor bypass line.

[0012] In some embodiments, the precursor bypass line is operably connected to a precursor trap, and the precursor trap is configured and arranged to remove unreacted precursor from the precursor bypass.

[0013] In some embodiments, the reactant bypass line is operably connected to a reactant trap, and the reactant trap is configured and arranged to remove unreacted reactant from the reactant bypass.

[0014] In some embodiments, the system further includes a purge gas recovery unit and a recovered purge gas line. The purge gas recovery unit is configured and arranged to recover used purge gas from at least one of the reactant bypass and the precursor bypass, thereby obtaining a recovered purge gas stream. The recovered purge gas line operably connects the purge gas recovery unit to the purge gas source to recycle the purge gas.

[0015] In some embodiments, the purge gas includes at least one of N 2 , H 2 and noble gases.

[0016] In some embodiments, the precursor trap includes a cold trap.

[0017] In some embodiments, the system further includes a collection well configured and arranged to receive unreacted precursors trapped by the cold trap.

[0018] In some embodiments, the precursor trap includes an adsorption trap.

[0019] In some embodiments, the system further includes a fractionation device configured and arranged to purify the unreacted precursors from the precursor trap to obtain a purified precursor stream.

[0020] In some embodiments, the fractionation device is operably connected to the precursor source to supply at least a portion of the purified precursor stream to the precursor source.

[0021] The present invention content is provided to introduce some concepts in a simplified form. These concepts are further described in detail in the following detailed description of the exemplary embodiments disclosed. The present invention content is not intended to identify the key features or essential features of the claimed subject matter, nor is it intended to be used to limit the scope of the claimed subject matter. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 An embodiment of a system 100 according to an embodiment of the present disclosure is shown.

[0023] Figure 2 An embodiment of a method as described herein is shown.

[0024] Figure 3 An embodiment of a purge gas recovery unit 300 as described herein is shown.

[0025] Figure 4 An embodiment of a system 400 according to an embodiment of the present disclosure is shown.

[0026] Figure 5 An embodiment of a method as described herein is shown.

[0027] It should be understood that the elements in the drawings are shown for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some elements in the figures may be exaggerated relative to other elements to help improve the understanding of the illustrated embodiments of the present disclosure. DETAILED DESCRIPTION

[0028] Although certain embodiments and examples are disclosed below, those skilled in the art will understand that the present invention extends beyond the specifically disclosed embodiments and / or uses of the present invention and their obvious modifications and equivalents. Therefore, it is intended that the scope of the present invention disclosed should not be limited by the specifically disclosed embodiments described below.

[0029] As used herein, the term "substrate" can refer to any one or more underlying materials, including any one or more underlying materials that can be modified or on which devices, circuits, or films can be formed. A "substrate" can be continuous or discontinuous; rigid or flexible; solid or porous; and combinations thereof. The substrate can be in any form, such as powder, plate, or workpiece. Plate-like substrates can include wafers of various shapes and sizes. Substrates can be made of semiconductor materials, including, for example, silicon, silicon germanium, silicon oxide, gallium arsenide, gallium nitride, and silicon carbide.

[0030] For example, substrates in powder form can be used in pharmaceutical manufacturing. Porous substrates can contain polymers. Examples of workpieces can include medical devices (such as stents and syringes), jewelry, tooling equipment, components for battery manufacturing (such as anodes, cathodes, or separators), or components of photovoltaic cells, etc.

[0031] A continuous substrate can extend beyond the boundaries of the processing chamber in which the deposition process occurs. In some processes, the continuous substrate can be moved through the processing chamber such that the process continues until the end of the substrate is reached. A continuous substrate can be provided from a continuous substrate feed system to allow for the manufacture and output of the continuous substrate in any suitable form.

[0032] Non-limiting examples of continuous substrates can include sheets, non-woven membranes, rolls, foils, meshes, flexible materials, bundles of continuous filaments or fibers (such as ceramic fibers or polymer fibers). A continuous substrate can also include a carrier or sheet on which a discontinuous substrate is mounted.

[0033] In the present disclosure, "gas" can include materials that are gases at normal temperature and pressure (NTP), evaporated solids, and / or evaporated liquids, and can consist of a single gas or a gas mixture as the case may be. Gases other than the process gases, i.e., gases that are not introduced through gas distribution components, other gas distribution devices, etc., can be used, for example, to seal the reaction space and can include sealing gases such as noble gases. In some cases, the term "precursor" can refer to a compound that participates in a chemical reaction to produce another compound, particularly a compound that constitutes the film matrix or the main framework of the film. The term "reactant" can be used interchangeably with the term precursor. The term "inert gas" can refer to a gas that does not participate in a chemical reaction and / or does not become part of the film matrix to a perceptible extent. Exemplary inert gases include helium, argon, and any combination thereof.

[0034] The term "deposition process" as used herein can refer to introducing precursors (and / or reactants) into a reaction chamber to deposit a layer on a substrate. A "cyclic deposition process" is an example of a "deposition process". The deposition process can include forming a solid reaction product starting from gaseous precursors and reactants.

[0035] The term "cyclic deposition process" can refer to the sequential introduction of precursors (and / or reactants) into a reaction chamber to deposit a layer on a substrate, and includes processing techniques such as atomic layer deposition (ALD), cyclic chemical vapor deposition (cyclic CVD), and hybrid cyclic deposition processes that include an ALD component and a cyclic CVD component. The cyclic deposition process may or may not include self-limiting surface reactions.

[0036] The term "atomic layer deposition" can refer to a vapor deposition process in which deposition cycles (usually multiple consecutive deposition cycles) are carried out in a processing chamber. The term atomic layer deposition as used herein also means to include processes designated by related terms, such as chemical vapor atomic layer deposition, atomic layer epitaxy (ALE), molecular beam epitaxy (MBE), molecular layer deposition (MLD), gas-source MBE, organometallic MBE, and chemical beam epitaxy when carried out with alternating pulses of precursor / reactant gas and purge gas (e.g., an inert carrier gas).

[0037] Typically, for an ALD process, during each cycle, a precursor is introduced into the reaction chamber and chemisorbed onto the deposition surface (e.g., a substrate surface that may include previously deposited material from a previous ALD cycle or other materials), and a monolayer or sub-monolayer of a material that does not readily react with additional precursor is formed (i.e., a self-limiting reaction). Thereafter, a reactant (e.g., another precursor or a reactive gas) may then be introduced into the processing chamber to convert the adsorbed precursor into the desired material on the deposition surface. The reactant is capable of further reacting with the precursor. During one or more cycles, e.g., during each step of each cycle, a purge step may be utilized to remove any excess precursor from the processing chamber and / or any excess reactant and / or reaction by-products from the reaction chamber.

[0038] As used herein, the term "purge" can refer to the process of providing an inert or substantially inert gas to a reactor chamber between two gas pulses that react with each other. For example, a purge may be provided between a precursor pulse and a reactant pulse, e.g., using nitrogen, to avoid or at least minimize gas-phase interactions between the precursor and the reactant. It should be understood that the purge can be carried out temporally or spatially, or both. For example, in the case of a temporal purge, the purge step may be used, for example, in the chronological order of providing a first precursor to the reactor chamber, providing a purge gas to the reactor chamber, and providing a second precursor to the reactor chamber, where the substrate on which the layer is deposited does not move. For example, in the case of a spatial purge, the purge step may take the form of moving the substrate from a first position where a first precursor is continuously supplied through a purge gas curtain to a second position where a second precursor is continuously supplied.

[0039] The illustrations presented herein are not meant to be actual views of any specific material, structure, or device, but are merely idealized representations for describing embodiments of the present disclosure.

[0040] The specific embodiments shown and described are illustrative of the invention and its best mode and are not intended to limit the scope of these aspects and embodiments in any way. In fact, for the sake of brevity, conventional manufacturing, connection, preparation, and other functional aspects of the system may not be described in detail. Additionally, the connecting lines shown in the figures are intended to represent exemplary functional relationships and / or physical couplings between various elements. Many alternative or additional functional relationships or physical connections may exist in the actual system and / or may not exist in some embodiments.

[0041] It should be understood that the configurations and / or methods described herein are exemplary in nature and that these specific embodiments or examples should not be considered limiting since many variations are possible. The specific routines or methods described herein may represent one or more of any number of processing strategies. Accordingly, the various acts shown may be performed in the order shown, in other orders, or in some cases, omitted.

[0042] The subject matter of the present disclosure includes all novel and non-obvious combinations and sub-combinations of various processes, systems, and configurations, as well as other features, functions, acts, and / or properties disclosed herein, and any and all equivalents thereof.

[0043] Referring Figure 1 , an embodiment of a system 100 in accordance with the present disclosure is described herein. System 100 includes a reaction chamber 110. System 100 further includes a precursor source 120. The precursor source includes a precursor 121. The precursor source 120 is operably connected to the reaction chamber 110 via a precursor line 125. Note that the term "line" as used herein may be used interchangeably with the word "tube". The precursor line 125 is provided with a precursor valve 126 operable to open and close the precursor line 125. System 100 further includes a reactant source 130. The reactant source includes a reactant 131. The reactant source 130 is operably connected to the reaction chamber 110 via a reactant line 135. The reactant line 135 is provided with a reactant valve 136 operable to open and close the reactant line 135. System 100 also includes a precursor sidestream line 122. The precursor sidestream line 122 is constructed and arranged to remove a precursor sidestream from the reaction chamber 110. The precursor sidestream line 122 is provided with a precursor sidestream valve 123 operable to open and close the precursor sidestream line 122. System 100 further includes a reactant sidestream line 132. The reactant sidestream line 132 is constructed and arranged to remove a reactant sidestream from the reaction chamber. The reactant sidestream line 132 is provided with a reactant sidestream valve 133 operable to open and close the reactant sidestream line.

[0044] System 100 may further include a controller 140. The controller 140 may include a memory 141. The memory may include computer-readable instructions that, when executed, cause the system to open the precursor pipeline 125, close the reactant pipeline 135, open the precursor bypass pipeline 122, and close the reactant bypass pipeline 122. Accordingly, precursors may be captured during the precursor pulse and optionally during a subsequent purge. By capturing precursors and reactants separately, the precursors and / or reactants may be more easily recycled or processed. It should be understood that the precursor pipeline 125 may be opened by opening the precursor valve 126. It should be understood that the reactant pipeline 135 may be closed by closing the reactant valve 136. It should be understood that the precursor bypass pipeline 122 may be opened by opening the precursor bypass valve 123. It should be understood that the reactant bypass pipeline 132 may be closed by closing the reactant bypass valve 133.

[0045] Additionally or alternatively, in some embodiments, the memory 141 may include computer-readable instructions that, when executed, cause the system to open the reactant pipeline 135, close the precursor pipeline 125, open the reactant bypass pipeline 132, and close the precursor bypass pipeline 122. Accordingly, reactants and reactant by-products may be captured during the reactant pulse and optionally during a subsequent purge. It should be understood that the reactant pipeline 135 may be opened by opening the reactant valve 136. It should be understood that the precursor pipeline 125 may be closed by closing the precursor valve 126. It should be understood that the reactant bypass pipeline 132 may be opened by opening the reactant bypass valve 133. It should be understood that the precursor bypass pipeline 122 may be closed by closing the precursor bypass valve 123.

[0046] Additionally or alternatively, in some embodiments, the memory 141 may include computer-readable instructions that, when executed, cause the system to perform a cyclic deposition process, an embodiment of which is shown by Figure 2 illustrated. Figure 2 The method shown includes step 211: positioning a substrate on a substrate support included in a reaction chamber. Then, the method includes performing a cyclic chemical vapor deposition process that includes repeatedly performing a plurality of cycles 216. Cycles from the plurality of cycles include a precursor pulse 212 and a reactant pulse 214. Subsequent precursor pulses 212 and reactant pulses 214 are separated by purges 213, 215 to prevent gas-phase mixing between the precursor and the reactant. The purge 213 that occurs after the precursor pulse 212 may be referred to as a post-precursor purge 213. The purge 215 that occurs after the reactant pulse 214 may be referred to as a post-reactant purge 215.

[0047] In some embodiments, the controller may include computer-readable instructions that, when executed, cause the system to actuate various pulse valves and outlet valves with a certain time delay to account for the time it takes for various gases to travel from their source streams to the respective side-stream pipelines. The time delay may be, for example, from at least 10 ms to at most 1 s, such as 100 ms. The outlet valves include a reactant side-stream valve 133 and a precursor side-stream valve 123. The pulse valves include a reactant valve 136 and a precursor valve 126.

[0048] The precursor pulse 212 includes exposing the substrate to a precursor, such as a metal precursor. This can be achieved by opening the precursor pipeline, closing the reactant pipeline, opening the precursor side-stream pipeline, and closing the reactant side-stream pipeline, which causes the precursor to be supplied to the reaction chamber and causes the precursor side-stream to be removed from the reaction chamber via the precursor side-stream pipeline.

[0049] The reactant pulse 214 includes exposing the substrate to a reactant, such as an oxygen reactant like oxygen or a nitrogen reactant like ammonia. This can be achieved by opening the reactant pipeline, closing the precursor pipeline, opening the reactant side-stream pipeline, and closing the precursor side-stream pipeline. This causes the reactant to be supplied to the reaction chamber and causes the reactant side-stream to be removed from the reaction chamber through the reactant side-stream pipeline. Thus, the precursor side-stream and the reactant side-stream can be separated, which allows for better elimination and / or recycling of the precursor and / or reactant.

[0050] A cyclic deposition process 216 may be performed until a material with a desired thickness has been deposited. After a material with a desired thickness has been deposited, the method ends 217. Of course, one or more cycles may optionally include additional pulses, such as one or more additional precursor pulses and one or more additional reactant pulses, which in turn may be separated from other reactant and precursor pulses by purging.

[0051] To facilitate purging 213, 215, the system 100 according to an embodiment of the present invention may further include a purge gas source 150. The purge gas source 150 may include a purge gas 151. The purge gas source 150 may be operably connected to the reaction chamber 110 through a purge gas pipeline 155. The purge gas pipeline 155 is provided with one or more purge gas valves 156 operable to open and close the purge gas pipeline 155.

[0052] During the post-precursor purge 213, unreacted precursors can be gradually removed from the reaction chamber 110. During the post-reactant purge 215, unreacted reactants can be gradually removed from the reaction chamber 110. Such unreacted precursors and unreacted reactants can be advantageously separately collected using embodiments of the present disclosure. In particular, the post-precursor purge can include opening the purge gas line 155, opening the precursor bypass line 122, closing the precursor line 125, closing the reactant line 135, and closing the reactant bypass line 132. It should be noted that the purge gas line 155 can be opened with a purge gas valve, the precursor bypass line 122 can be opened with a precursor bypass valve 123, the precursor line 125 can be closed with a precursor valve 126, the reactant line 135 can be closed with a reactant valve 136, and the reactant bypass line 132 can be closed with a reactant bypass valve 133. Similarly, the post-reactant purge 215 can include opening the purge gas line 135, e.g., via a purge gas valve 136; opening the reactant bypass line 132, e.g., via a reactant bypass valve 133; closing the precursor line 125, e.g., via a precursor valve 126; closing the reactant line 135, e.g., via a reactant valve 136; and closing the precursor bypass line 122, e.g., via a precursor bypass valve 123. Thus, separation of the precursor and reactant bypass can be achieved, which can better eliminate and / or recycle at least one of the precursor and reactant.

[0053] In some embodiments, the precursor bypass line 122 is operably connected to a precursor trap 160. The precursor trap 160 can be constructed and arranged to remove unreacted precursors from the precursor bypass. Thus, the precursors can be recovered, which is advantageous. In fact, in semiconductor deposition equipment such as atomic layer deposition equipment or plasma-enhanced atomic layer deposition equipment, a large portion of the precursors used are wasted because only a small portion of the precursors are used during a pulse. By capturing the precursors in the precursor trap 160 (e.g., a cold trap or an adsorption trap), precursor waste can be inhibited.

[0054] For example, a cold trap can condense or deposit reaction gases such as precursors and ALD by-products thereon, thereby removing them from the precursor bypass. For example, an adsorption trap can adsorb and / or sorb reaction gases, e.g., precursors and ALD by-products, to remove them from the precursor bypass.

[0055] In some embodiments, the system 100 includes a plurality of precursor traps 160, e.g., 2, 3, 4, 5, 6, or more precursor traps 160. The plurality of precursor traps 160 can be arranged in series, in parallel, or in a hybrid configuration including series and parallel arrangements. The plurality of precursor traps 160 can enhance precursor capture, or enhance the purity of the captured precursors, e.g., by purification techniques such as fractional condensation.

[0056] In some embodiments, the captured precursors can be further purified, e.g., by fractionation. Precursor purification can be done in situ, e.g., in a system according to an embodiment of the present disclosure. Alternatively, it can also be done near the system. Alternatively, precursor purification can be done off-site.

[0057] The materials captured by the precursor trap 160 can be stored in the precursor trap itself, or they can be removed by a particular type of removal device such as an evacuation device. Additionally or alternatively, in some embodiments, the system 100 can further include a collection well that is configured and arranged to accommodate unreacted precursors trapped by the cold trap.

[0058] In some embodiments, the materials captured by the precursor trap 160 can be processed and rendered harmless in an elimination unit (not shown), which can be part of the presently described system 100 or can be located elsewhere, e.g., on-site or off-site. Alternatively, the materials captured by the precursor trap 160 can be provided to the precursor purification unit 167. The precursor purification unit 167 can be provided with a recycled precursor pump (not shown) to pump the purified precursor to the precursor source 120. The precursor purification unit 167 can be operably connected to the precursor trap 160 via a trapped precursor line 169. The precursor purification unit 167 can be operably connected to the precursor source 120 via a purified precursor line 168, which is configured and arranged to provide the purified precursor from the precursor purification unit 167 to the precursor source 120. For example, the precursor purification unit 167 can include a fractionation device. The fractionation device can be configured and arranged to purify unreacted precursors from the precursor trap. Thus, a purified precursor stream can be obtained. In some embodiments, the fractionation device is operably connected to the precursor source to provide at least a portion of the purified precursor stream to the precursor source.

[0059] In some embodiments, the reactant sidestream line 132 is operably connected to the reactant trap 170. The reactant trap 170 can be configured and arranged to remove unreacted reactants from the reactant sidestream. Thus, the reactants can be recovered, which is advantageous. In fact, in semiconductor deposition equipment such as atomic layer deposition equipment or plasma enhanced atomic layer deposition equipment, most of the reactants used are wasted because only a small portion of the reactants are used during a pulse. By capturing the reactants in the reactant trap 170 such as a cold trap or an adsorption trap, reactant waste can be reduced. In some embodiments, the captured reactants can be further purified, e.g., by fractionation. Reactant purification can be done in situ, e.g., in a system according to an embodiment of the present disclosure. Alternatively, it can also be done near the system. Alternatively, reactant purification can be done off-site.

[0060] In some embodiments, system 100 includes a plurality of reactant traps 170, such as 2, 3, 4, 5, 6 or more reactant traps 170. The plurality of reactant traps 170 may be arranged in series, in parallel, or in a hybrid configuration including series and parallel arrangements. The plurality of reactant traps 170 can enhance reactant capture.

[0061] In some embodiments, system 100 as described herein may further include a purge gas recovery unit 180 and a recovered purge gas line 185. In some embodiments, the purge gas includes at least one of N 2 and a noble gas. Suitable noble gases may be selected from He, Ne, Ar, Kr, and Xe. The purge gas recovery unit 180 may be configured and arranged to recover used purge gas from at least one of the reactant side stream and the precursor side stream, thereby obtaining a recovered purge gas stream. The recovered purge gas line 185 may be operably connected from the purge gas recovery unit 180 to a purge gas source to recycle the purge gas.

[0062] In fact, by passing the exhaust gas from the reaction chamber through one or a series of precursor traps and / or reaction traps, such as an adsorption unit or a cold trap, various by-products, such as condensable by-products, as well as unreacted precursors and reactants, can be removed from the gas phase and collected for recycling or appropriate treatment. The carrier gas leaving one or more precursor traps may have a high enough purity for reuse or recycling / upgrading (e.g., running a further process or for use, for example, in a nitrogen supply for a vacuum pump). For example, the purity of the gas stream, such as the carrier gas stream, can be monitored by an in-line gas analyzer.

[0063] Recycling an inert gas stream, such as a carrier gas, can advantageously reduce the carbon footprint associated with unnecessary losses of process gases to the exhaust stream, increase scrubber life, and reduce the cost of tool operation by reducing argon / nitrogen costs. In fact, in some systems, the reaction chamber exhaust gas stream may be treated by a scrubber (which needs to be replaced periodically) before being vented to the atmosphere as waste. Preventing such unnecessary losses of inert gases, such as argon and nitrogen, is a significant potential source of carbon footprint and cost reduction. The resulting lower process gas requirements can also reduce the tool footprint.

[0064] In some embodiments, the purge gas recovery unit 180 is fluidly connected to the reactant trap 170. Thus, at least some of the purge gas passing through the reactant trap 170 can be recovered in the purge gas recovery unit 180. For example, such a fluid connection can be achieved through a reactant capture - purge gas recovery unit line 172, and the line 172 is provided with a corresponding check valve 173.

[0065] In some embodiments, the purge gas recovery unit 180 is fluidly connected to the precursor trap 160. Accordingly, at least some of the purge gas passing through the precursor trap 160 can be recovered in the purge gas recovery unit 180. For example, such a fluid connection can be achieved through the precursor capture - purge gas recovery unit pipeline 162, which is provided with a corresponding check valve 163.

[0066] According to Figure 1 the embodiment of, system 100 may include one or more pumps. For example, system 100 may include a recovered purge gas pump 189, which is disposed on the recovered purge gas pipeline 185. The recovered purge gas pump 189 and optional additional pumps can advantageously provide the required pressure gradient for the gas to flow through system 100. In some embodiments, according to Figure 1 the embodiment of, system 100 further includes one or more of a precursor pump (not shown) and a reactant pump (not shown). The precursor pump can be configured and arranged to pump the purified precursor to the precursor source 120. The reactant pump can be configured and arranged to pump the purified reactant to the reactant source 130.

[0067] According to Figure 1 the embodiment of, system 100 may include an exhaust pipeline 190. One or more exhaust pipelines 190 can provide at least a portion of the recovered purge gas stream to the atmosphere or an emission reduction system. The exhaust pipeline 190 can be fluidly connected to the recovered purge gas pipeline 185. The exhaust pipeline 190 can include an exhaust valve 193, such as a check valve, which can be configured and arranged to prevent contaminants such as atmospheric gases from flowing back into system 100.

[0068] The recovered purge gas pipeline 185 can be provided with a recovered purge gas valve 183, which can be any suitable valve. The recovered purge gas valve 183 can be opened to allow the purge gas to recirculate, or can be closed to prevent the purge gas from recirculating. The recovered purge gas valve 183 can be disposed on the recovered purge gas line 185 downstream of the exhaust pipeline 190.

[0069] In some embodiments, the reactant purification unit 177 can be operably connected to the reactant source 130 through a purified reactant pipeline 178, which is configured and arranged to provide the purified reactant from the reactant purification unit 177 to the reactant source 130. Suitably, the reactant purification unit 177 can include a pump (not shown), which is configured and arranged to pump the purified reactant from the reactant purification unit 177 to the reactant source 130.

[0070] Referring to Figure 3Describe an embodiment of a purge gas recovery unit 300. In this embodiment, the purge gas recovery unit 300 includes a cold trap 310 and an adsorption unit 320 in series, which together can suitably purify the used purge gas stream conveyed by the used purge gas flow line 315 to form a purged purge gas stream conveyed by the purged purge gas flow line 325. The cold trap 310 can be operably connected to the adsorption unit 320 through the partially purified purge gas line 316. The purified purge gas stream 325 can be used in part or in whole as the purge gas stream in the system according to the embodiments of the present disclosure. Additionally or alternatively, the purified purge gas stream 325 can be used in part or in whole for different purposes, such as a ballast gas in one or more pumps. It should be noted that the cold trap can remove precursors and reaction by-products. Although such a system can effectively remove substances with low vapor pressure at the cold trap temperature, it may be advantageous to remove reaction by-products that are gaseous at low temperatures in different ways. In fact, gases such as CH 4 , CO 2 , CO, O 2 can be suitably removed using different systems such as adsorption traps. Suitable adsorption traps can include porous adsorption media that adsorb gases that are difficult to remove using a cold trap.

[0071] In some embodiments, the purge gas recovery unit as described herein may include one or more scrubbers. Advantageously, the scrubber can include a reaction medium capable of reacting with at least one of the precursor and the reactant. Additionally or alternatively, the purge gas recovery unit as described herein can include two or more scrubbers, which can be arranged in a series, parallel, or hybrid configuration. For example, the purge gas recovery unit as described herein can include a reactant scrubber and a precursor scrubber arranged in series. For example, the reactant scrubber can be located upstream of the precursor scrubber. For example, the precursor scrubber can be located upstream of the reactant scrubber. The reactant scrubber can include a reaction medium that is configured and arranged to react with the reactant. The precursor scrubber can include a reaction medium that is configured and arranged to react with the precursor. In addition to or as an alternative to one or more adsorption traps, one or more scrubbers can be used.

[0072] It should be noted that scrubbers and adsorption traps are known in the art.

[0073] Reference Figure 4 , an embodiment of a system 400 according to the present disclosure is described herein. The system 400 can advantageously employ a cyclic gas phase process, such as atomic layer deposition, atomic layer etching, and their plasma-enhanced variants.

[0074] System 400 includes a precursor line 420 provided with a precursor valve 421. The precursor valve 421 is configured and arranged to open and close the precursor line 420. System 400 further includes a precursor purge gas line 425 provided with a precursor purge gas valve 426. The precursor purge gas valve 426 is configured and arranged to open and close the precursor purge gas line 425. The precursor line 420 and the precursor purge gas line 425 may be combined into a combined precursor line 427 downstream of the precursor valve 421 and the precursor purge gas valve 426. The combined precursor line 427 is fluidly connected to the reaction chamber 410. In some embodiments, the combined precursor line 427 may be omitted, in which case the precursor line 420 and the precursor purge gas line 425 may be directly fluidly connected to the reaction chamber 410.

[0075] System 400 further includes a reactant line 430 provided with a reactant valve 431. The reactant valve 431 is configured and arranged to open and close the reactant line 430. System 400 further includes a reactant purge gas line 435 provided with a reactant purge gas valve 436. The reactant purge gas valve 436 is configured and arranged to open and close the reactant purge gas line 435. The reactant line 430 and the reactant purge gas line 435 may be combined into a combined reactant line 437 downstream of the reactant valve 431 and the reactant purge gas valve 436. The combined reactant line 437 is fluidly connected to the reaction chamber 410. In some embodiments, the combined reactant line 437 may be omitted, in which case the reactant line 430 and the reactant purge gas line 435 may be directly fluidly connected to the reaction chamber 410.

[0076] As Figure 4 shown in the embodiments of, the system 400 described herein may include separate exhaust lines 440, 450 for the precursor and the reactant, including a precursor exhaust line 440 and a reactant exhaust line 450. The precursor exhaust line 440 may be provided with a precursor exhaust valve 441. The reactant exhaust line 450 may be provided with a reactant exhaust valve 451. Downstream of the precursor exhaust valve 441, the precursor exhaust line 440 may be operably connected to a precursor trap 460, as described herein. Downstream of the precursor trap 460, the precursor exhaust line 440 may be provided with a post-precursor capture valve 470. Downstream of the reactant exhaust valve 451, the reactant exhaust line 450 may be fluidly connected to a pump 480. Similarly, downstream of the post-precursor capture valve 470, the precursor exhaust line 440 may be fluidly connected to the pump 480. The exhaust gas from the pump 480 may be, for example, discharged or sent to an abatement facility for treating the reactants contained in the exhaust gas.

[0077] Figure 5 An embodiment of a method for operating the valves in the system 400 according to Figure 4 is shown. In particular,Figure 5 Shows the open and closed positions during the precursor pulse 501, precursor purge 502, reactant pulse 503, and reactant purge 504.

[0078] The precursor valve 421 is initially opened during the precursor pulse 501 and then closed during the precursor purge 502. The precursor purge gas valve 426 is initially closed during the precursor pulse 501 and then opened during the precursor purge 502. The precursor exhaust valve 441 is opened during the precursor pulse 501 and the precursor purge 502. The reactant valve 431, the reactant purge gas valve 436, and the reactant exhaust valve 451 are closed during the precursor pulse 501 and the precursor purge 502.

[0079] The reactant valve 431 is initially opened during the reactant pulse 503 and then closed during the reactant purge 504. The reactant purge gas valve 436 is initially closed during the reactant pulse 503 and then opened during the reactant purge 504. The reactant exhaust valve 451 is opened during the reactant pulse 503 and the reactant purge 504. The precursor valve 421, the precursor purge gas valve 426, and the precursor exhaust valve 441 are closed during the reactant pulse 503 and the reactant purge 504. Thus, the precursor can be effectively trapped in the precursor trap 460 while minimizing the amount of reactant trapped in the precursor trap 460. This may be advantageous as it allows minimizing or eliminating unwanted side reactions between the precursor and the reactant in the precursor trap.

[0080] In some embodiments, the precursor can be recovered from the precursor trap 460. For example, this can be achieved by isolating the precursor trap with a valve and replacing the trap with a new empty trap. The filled trap can be transported to a dedicated precursor purification device to purify the precursor using methods known in the art.

[0081] In some embodiments, the precursor can include one or more metals, such as transition metals, post-transition metals, and rare earth metals. In some embodiments, the precursor includes Group IV elements, such as silicon or germanium.

[0082] Suitable reactants can include one or more oxygen reactants, such as selected from H 2 O, O 2 and O 3 .

[0083] Suitable reactants can include one or more carbon reactants, such as selected from CO and CO 2 .

[0084] Suitable reactants can include nitrogen reactants, such as selected from NH 3 , N 2 O, NO, NO 2 and NO 3 .

[0085] Suitable reactants can include hydrogen reactants such as H 2 .

[0086] Suitable purge gases can be gases such as N 2 and noble gases. Suitable noble gases can include He, Ne, Ar, Kr, and Xe.

[0087] It should be understood that in some embodiments, the described multiple systems can be included in a semiconductor processing facility. In such embodiments, the systems can be operably connected to a central abatement facility. The central abatement facility can include at least one of one or more central purge gas purge units, one or more central precursor purge units, and a central reactant purge unit. At least one of the central purge gas purge unit, the central precursor purge unit, and the central reaction purge unit can be operably connected to more than one system as described herein. Thus, at least one of the purge gases, precursors, and reactants from multiple systems can be purified by a single purification unit.

Claims

1. A system comprising: - reaction chamber; - a precursor source comprising a precursor, the precursor source being operatively connected to the reaction chamber via a precursor line, the precursor line being provided with a precursor valve operable to open and close the precursor line; - a reactant source comprising a reactant, the reactant source being operatively connected to the reaction chamber via a reactant line, the reactant line being provided with a reactant valve operable to open and close the reactant line; - a precursor side stream line constructed and arranged to remove a precursor side stream from the reaction chamber, the precursor side stream line being provided with a precursor side stream valve operable to open and close the precursor side stream line; - a reactant sidestream line constructed and arranged to remove a reactant sidestream from the reaction chamber, the reactant sidestream line being provided with a reactant sidestream valve operable to open and close the reactant sidestream line.

2. The system of claim 1 further comprising a controller comprising a memory containing computer-readable instructions which, when executed, cause the system to open the precursor line, close the reactant line, open the precursor side stream line, and close the reactant side stream line.

3. The system of claim 1 further comprising a controller comprising a memory containing computer-readable instructions which, when executed, cause the system to open the reactant line, close the precursor line, open the reactant side flow line, and close the precursor side flow line.

4. The system of claim 1 , further comprising a controller, the controller comprising a memory containing computer readable instructions that, when executed, cause the system to perform a cyclic deposition process, the cyclic deposition process comprising a plurality of cycles, a cycle from the plurality of cycles comprising a precursor pulse and a reactant pulse; - Among them, the precursor Pulsing includes opening the precursor line, closing the reactant line, opening the precursor sidestream line, and closing the reactant sidestream line, thereby providing the precursor to the reaction chamber and removing the precursor sidestream from the reaction chamber through the precursor sidestream line; and - wherein the reactant pulse comprises opening a reactant line, closing a precursor line, opening a reactant side stream line, and closing a precursor side stream line, thereby providing the reactant to the reaction chamber and removing the reactant side stream from the reaction chamber through the reactant side stream line.

5. The system according to any one of claims 1 to 4, further comprising a purge gas source comprising a purge gas, the purge gas source being operably connected to the reaction chamber via a purge gas line, the purge gas line being provided with one or more purge gas valves operable to open and close the purge gas line.

6. The system according to claim 5, wherein: The cyclic deposition process also includes a post-precursor purge and a post-reactant purge. - performing a post-precursor purge after the precursor pulse, wherein the post-precursor purge comprises opening the purge gas line, opening the precursor side flow line, closing the precursor line, closing the reactant line, and closing the reactant side flow line; - performing a post-reactant purge after the reactant pulse, wherein the post-reactant purge comprises opening a purge gas line, opening a reactant side stream line, closing a precursor line, closing a reactant line, and closing a precursor side stream line.

7. A system according to any one of claims 1 to 6, wherein: The precursor sidestream line is operably connected to a precursor trap constructed and arranged to remove unreacted precursor from the precursor sidestream.

8. The system according to any one of claims 1 to 7, wherein: The reactant side stream line is operably connected to a reactant trap constructed and arranged to remove unreacted reactants from the reactant side stream.

9. The system according to any one of claims 7 or 8, further comprising a purge gas recovery unit and a recovered purge gas pipeline, - a purge gas recovery unit constructed and arranged for recovering spent purge gas from at least one of the reactant side stream and the precursor side stream, thereby obtaining a recovered purge gas stream; - A recovered purge gas line operatively connects a purge gas recovery unit to said purge gas source to recover purge gas.

10. The system according to claim 9, wherein: The purge gas includes at least one of N2, H2 and a rare gas.

11. A system according to any one of claims 7 to 10, wherein: The precursor trap comprises a cold trap.

12. The system of claim 11, further comprising a collection well constructed and arranged to contain unreacted precursor captured by the cold trap.

13. A system according to any one of claims 7 to 11, wherein: The precursor trap comprises an adsorption trap.

14. The system according to any one of claims 7 to 13, further comprising a fractionation device constructed and arranged to purify unreacted precursor from the precursor trap to obtain a purified precursor stream.

15. The system of claim 14, wherein: The fractionation device is operably connected to the precursor source to provide at least a portion of the purified precursor stream to the precursor source.

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