Process gas recycling

Abstract

To provide systems and methods that may be useful in the context of gas reuse thin film deposition equipment.SOLUTION: The present disclosure particularly relates to separate collection and recycling of gases such as precursors, reactants, and purge gases. A system 100 includes: a reaction chamber 110; a precursor source 120 operationally connected to the reaction chamber by means of a precursor line 125, the precursor line being disposed with a precursor valve 126 that is operable to open and close the precursor line; a reactant source 130 operationally connected to the reaction chamber by means of a reactant line 135, the reactant line being disposed with a valve 136 that is operable to open and close the reactant line; a precursor side stream line disposed with a valve 123 that is operable to open and close a precursor side stream line 122; and a reactant side stream line disposed with a valve 133 that is operable to open and close a reactant side stream line 132.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] Embodiments of the present disclosure belong to the field of vapor thin film processing. Embodiments of the present disclosure are particularly related to gas recycling in thin film processing.

Background Art

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

[0003] Not all precursors are consumed during thin film processing. Therefore, there is a possibility of recycling the precursors.

[0004] Not all reactants are consumed during thin film processing. Therefore, there is a possibility of recycling the reactants.

[0005] Inert process gases may not be substantially changed by thin film processing. Therefore, there is a possibility of recycling the inert process gases.

Summary of the Invention

Means for Solving the Problems

[0006] In one embodiment, a system described in the present disclosure includes a reaction chamber, a precursor source having a precursor, the precursor source being operably connected to the reaction chamber by a precursor line and including a precursor valve operable to open and close the precursor line, a reactant source containing a reactant, the reactant source being operably connected to the reaction chamber by a reactant line and including a reactant valve operable to open and close the reactant line, a precursor sidestream line constructed and arranged to remove a precursor sidestream from the reaction chamber and including a precursor sidestream valve operable to open and close the precursor sidestream line, and a reactant sidestream line constructed and arranged to remove a reactant sidestream from the reaction chamber and including a reactant sidestream valve operable to open and close the reactant sidestream line.

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

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

[0009] In some embodiments, the system further comprises a controller, the controller comprising a memory storing computer-readable instructions that, when executed, cause the system to perform a periodic deposition process that includes a plurality of cycles, each cycle of the plurality of cycles including a precursor pulse and a reactant pulse, the precursor pulse including opening a precursor line, closing a reactant line, opening a precursor side flow line, and closing a reactant side flow line, thereby supplying a precursor to the reaction chamber and configured to remove a precursor side flow from the reaction chamber via the precursor side flow line, the reactant pulse including opening a reactant line, closing a precursor line, opening a reactant side flow line, and closing a precursor side flow line, thereby supplying a reactant to the reaction chamber and configured to remove a reactant side flow from the reaction chamber via the reactant side flow line.

[0010] In some embodiments, the system further comprises a purge gas source including a purge gas, the purge gas source being operably connected to the reaction chamber by a purge gas line, the purge gas line comprising one or more purge gas valves operable to open and close the purge gas line.

[0011] In some embodiments, the periodic deposition process further includes a post-precursor purge and a post-reactant purge, the post-precursor purge being performed after the precursor pulse and including 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, the post-reactant purge being performed after the reactant pulse and including opening the purge gas line, opening the reactant side flow line, closing the precursor line, closing the reactant line, and closing the precursor side flow line. In some embodiments, the precursor side flow line is operably connected to a precursor trap, the precursor trap being constructed and arranged to remove unreacted precursor from the precursor side flow.

[0012] In some embodiments, the reactant side stream line is operably connected to a reactant trap, and the reactant trap is constructed and arranged to remove unreacted reactants from the reactant side stream. In some embodiments, the system further comprises a purge gas recovery unit and a recovered purge gas line, the purge gas recovery unit being constructed 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, and the recovered purge gas line operably connecting the purge gas recovery unit to a purge gas source for recycling the purge gas.

[0013] In some embodiments, the purge gas comprises at least one of N 2 , H 2 , and a noble gas.

[0014] In some embodiments, the precursor trap includes a cold trap. In some embodiments, the system further comprises a collection well constructed and arranged to hold unreacted precursors captured by the cold trap.

[0015] In some embodiments, the precursor trap comprises an adsorption trap.

[0016] In some embodiments, the system further comprises a fractional distillation apparatus constructed and arranged to purify unreacted precursors from the precursor trap, thereby obtaining a purified precursor stream.

[0017] In some embodiments, the fractional distillation apparatus is operably connected to a precursor source and configured to provide at least a portion of the purified precursor stream to the precursor source.

[0018] This summary is provided to introduce some concepts in a simplified form. These concepts will be described in more detail in the detailed description of the exemplary embodiments of the disclosure below. This summary 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

[0019]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Best Mode for Carrying Out the Invention

[0020] It will be understood that the elements in the figures are illustrated for simplicity and clarity and are not necessarily drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to assist in understanding the exemplary embodiments of the present disclosure.

[0021] Although certain embodiments and examples are disclosed below, it will be understood by those skilled in the art that the invention extends beyond the specifically disclosed embodiments and / or uses of the invention, as well as their obvious modifications and equivalents. Therefore, it is intended that the scope of the disclosed invention should not be limited by the specific disclosed embodiments described below.

[0022] As used herein, the term "substrate" may refer to one or more optional underlying materials that may be modified or on which a device, circuit, or film may be formed. A "substrate" may be continuous or discontinuous, rigid or flexible, solid or porous, and combinations thereof. The substrate may be in any form such as a powder, plate, or workpiece. Examples of plates include wafers of various shapes and sizes. The substrate may be made of, for example, semiconductor materials such as silicon, silicon germanium, silicon oxide, gallium arsenide, gallium nitride, and silicon carbide.

[0023] As an example, a substrate in the form of a powder may have applications in pharmaceutical manufacturing. The porous substrate may include a polymer. Examples of workpieces may include medical devices (e.g., stents and syringes), jewelry, tour devices, components for battery manufacturing (e.g., anodes, cathodes, or separators), or components of a photovoltaic cell.

[0024] A continuous substrate may extend beyond the boundaries of a process chamber where a deposition process occurs. In some processes, the continuous substrate may move through the process chamber, thereby allowing the process to continue until it reaches the end of the substrate. The continuous substrate may be supplied from a continuous substrate supply system in any suitable form to enable the manufacture and output of the continuous substrate.

[0025] Non-limiting examples of continuous substrates may include sheets, non-woven membranes, rolls, foils, webs, flexible materials, bundles of continuous filaments or fibers (e.g., ceramic fibers or polymer fibers). Also, the continuous substrate may include a carrier or sheet on which a discontinuous substrate is placed.

[0026] In this disclosure, "gas" can include materials that are gaseous at normal temperature and pressure (NTP), vaporized solids, and / or vaporized liquids, and can in some situations consist of a single gas or a mixture of gases. Gases other than process gases, i.e., gases introduced without passing through a gas distribution assembly, other gas distribution devices, or the like, can be used, for example, to seal a reaction space and can include seal 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, specifically a compound that constitutes the matrix or main framework of a 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.

[0027] As used in this disclosure, the term "deposition process" can refer to introducing a precursor (and / or reactant) into a reaction chamber to deposit a layer over a substrate. A "cyclic deposition process" is an example of a "deposition process". A deposition process can include the formation of a solid reaction product starting from gaseous precursors and reactants.

[0028] The term "cyclic deposition process" or "cyclical deposition process" can refer to the sequential introduction of a precursor (and / or reactant) into a reaction chamber for depositing 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 ALD components and cyclic CVD components. A cyclic deposition process may or may not include self-limiting surface reactions.

[0029] The term "atomic layer deposition" can refer to a deposition cycle, typically a vapor deposition process in which a plurality of consecutive deposition cycles are performed within a process chamber. Also, as used in this disclosure, the term atomic layer deposition, when performed using alternating pulses of one or more precursor / reactant gases and one or more purge (e.g., inert carrier) gases, also means encompassing processes designated by related terms such as atomic layer chemical vapor deposition, atomic layer epitaxy (ALE), molecular beam epitaxy (MBE), gas source MBE, organometallic MBE, and chemical beam epitaxy.

[0030] Generally, in an ALD cycle, during each cycle, a precursor is introduced into the reaction chamber and chemisorbs onto a deposition surface (e.g., a substrate surface that may include material deposited by a previous ALD cycle or other material), forming a monolayer or sub-monolayer of material that does not readily react with another precursor (i.e., a self-limiting reaction). Thereafter, a reactant (e.g., another precursor or reaction gas) may then be introduced into the process chamber for use in converting the chemisorbed precursor into the desired material on the deposition surface. The reactant may be one that has the ability to react further with the precursor. During one or more cycles (e.g., during each step of each cycle), a purge step may be used to remove any excess precursor from the process chamber and / or to remove any excess reactant and / or reaction by-products from the reaction chamber.

[0031] As used in this disclosure, the term "purge" may refer to a procedure in which an inert gas or a substantially inert gas is supplied to a reaction chamber between pulses of gases that react with each other. For example, a purge (e.g., a purge using nitrogen gas) may be supplied between a precursor pulse and a reactant pulse to avoid or at least minimize gas-phase interactions between the precursor and the reactant. It will be understood that the purge can be achieved either temporally, spatially, or both. For example, in the case of a temporal purge, the purge step may, for example, in a time series, provide a first precursor to the reaction chamber, provide a purge gas to the reaction chamber, and provide a second precursor to the reaction chamber, and can be used without moving the substrate on which the layer is deposited. 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.

[0032] The examples presented in this disclosure are not meant to be the actual form of any particular material, structure, or device, but are merely idealized representations used to illustrate embodiments of this disclosure.

[0033] The specific examples illustrated and described are examples of the invention and its best mode, and are not intended to limit the scope of the aspects and implementations in any way. Also, for the sake of brevity, conventional manufacturing, related, preparation, and other functional aspects of the system may not be described in detail. Further, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical connections between the 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.

[0034] The configurations and / or approaches described in this disclosure are exemplary in nature, and it should be understood that these specific embodiments or examples should not be considered in a limiting sense as numerous variations are possible. The specific routines or methods described in this disclosure may be typical examples of one or more of any number of process strategies. Therefore, the various operations illustrated may be performed in the order illustrated, in other orders, or in some cases, omitted.

[0035] The subject matter of this disclosure encompasses not only all novel and non-obvious combinations and sub-combinations of the various processes, systems, and structures disclosed in this disclosure, as well as other configurations, functions, operations, and / or characteristics, but also all equivalents thereof.

[0036] Referring to FIG. 1, an embodiment of a system 100 according to the present disclosure is described herein. The system 100 includes a reaction chamber 110. The system 100 includes a precursor source 120. The precursor source includes a precursor 121. The precursor source 120 is operably connected to the reaction chamber 110 by a precursor line 125. As used herein, the term "line" can be used interchangeably with the term "tube". The precursor line 125 includes a precursor valve 126 operable to open and close the precursor line 125. The 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 by a reactant line 135. The reactant line 135 includes a reactant valve 136 operable to open and close the reactant line 135. The system 100 further 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 includes a precursor sidestream valve 123 operable to open and close the precursor sidestream line 122. The 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. A reactant sidestream valve 133 operable to open and close the reactant sidestream line is provided in the reactant sidestream line 132.

[0037] System 100 may further be configured to include a controller 140. The controller 140 may be configured to include a memory 141. The memory may be configured to store computer-readable instructions that, when executed, open the precursor line 125, close the reactant line 135, open the precursor side stream line 122, and close the reactant side stream line 122 of the system. Accordingly, the precursor can be captured during the precursor pulse and optionally during a subsequent purge. By separately capturing the precursor and the reactant, the precursor and / or the reactant can be recycled or processed more easily. It will be appreciated that the precursor line 125 can be opened by opening the precursor valve 126. It will be appreciated that the reactant line 135 can be closed by closing the reactant valve 136. It will be appreciated that the precursor side stream line 122 can be opened by opening the precursor side stream valve 123. It will be appreciated that the reactant side stream line 132 can be closed by closing the reactant side stream valve 133.

[0038] Additionally, or alternatively, and in some embodiments, the memory 141 may be configured to store computer-readable instructions that, when executed, open the reactant line 135, close the precursor line 125, open the reactant side stream line 132, and close the precursor side stream line 122 of the system. Accordingly, the reactant and the by-products of the reactant can be captured during the reactant pulse and optionally during a subsequent purge. It will be appreciated that the reactant line 135 can be opened by opening the reactant valve 136. It will be appreciated that the precursor line 125 can be closed by closing the precursor valve 126. It will be appreciated that the reactant side stream line 132 can be opened by opening the reactant side stream valve 133. It will be appreciated that the precursor side stream line 122 can be closed by closing the precursor side stream valve 123.

[0039] Additionally or alternatively, and in some embodiments, memory 141 may be configured to store computer-readable instructions that, when executed, cause the system to perform a periodic deposition process. One such embodiment is illustrated in FIG. 2. The method illustrated in FIG. 2 includes a step 211 of disposing a substrate on a substrate support within a reaction chamber. Next, the method includes performing a periodic vapor deposition process that includes repeatedly executing a plurality of cycles 216. Each cycle of the plurality of cycles includes 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 performed after the precursor pulse 212 may be referred to as a post-precursor purge 213. The purge 215 performed after the reactant pulse 214 may be referred to as a post-reactant purge 215.

[0040] In some embodiments, the controller may be configured to include computer-readable instructions that, when executed, cause the system to operate various pulse valves and outlet valves with some time delay that gives the various gases time to flow from their sources to their respective side-stream lines. The time delay can be, for example, at least 10 milliseconds to a maximum of 1 second, for example, 100 milliseconds. 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.

[0041] The precursor pulse 212 includes exposing the substrate to a precursor such as a metal precursor. This can be done by opening the precursor line, closing the reactant line, opening the precursor side-stream line, closing the reactant side-stream line, feeding the precursor into the reaction chamber, and thereby removing the precursor side-stream from the reaction chamber via the precursor side-stream line.

[0042] 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 done by opening the reactant line, closing the precursor line, opening the reactant side flow line, and closing the precursor side flow line. Thereby, the reactant is supplied to the reaction chamber, and the reactant side flow is removed from the reaction chamber via the reactant side flow line. Thus, the precursor side flow and the reactant side flow can be separated, enabling better removal and / or recycling of the precursor and / or reactant.

[0043] The periodic deposition process 216 may be configured to be carried out until a material having a desired thickness is deposited. After the material is deposited to the desired thickness, the method ends 217. Of course, one or more of the cycles may optionally include additional pulses such as one or more additional precursor pulses and one or more additional reactant pulses, which can then be separated from other reactant and precursor pulses by purging.

[0044] To facilitate the purges 213, 215, the system 100 according to one embodiment of the present disclosure may further include a purge gas source 150. The purge gas source 150 may be configured to include a purge gas 151. The purge gas source 150 may be operably connected to the reaction chamber 110 by a purge gas line 155. The purge gas line 155 includes one or more purge gas valves 156 operable to open and close the purge gas line 155.

[0045] In the post-precursor purge 213, it may be configured to gradually remove unreacted precursors from the reaction chamber 110. In the post-reactant purge 215, it may be configured to gradually remove unreacted reactants from the reaction chamber 110. According to an embodiment of the present disclosure, there is an effect that these unreacted precursors and unreacted reactants can be collected separately. In particular, the post-precursor purge may include opening the purge gas line 155, opening the precursor side stream line 122, closing the precursor line 125, closing the reactant line 135, and closing the reactant side stream line 132. Note that the purge gas line 155 can be opened by a purge gas valve, the precursor side stream line 122 can be opened by a precursor side stream valve 123, the precursor line 125 can be closed by a precursor valve 126, the reactant line 135 can be closed by a reactant valve 136, and the reactant side stream line 132 can be closed by a reactant side stream valve 133. Similarly, the post-reactant purge 215 may include, for example, opening the purge gas line 135 by a purge gas valve 136, opening the reactant side stream line 132 by a reactant side stream valve 133, closing the precursor line 125 by a precursor valve 126, closing the reactant line 135 by a reactant valve 136, and closing the precursor side stream line 122 by a precursor side stream valve 123. Therefore, separation of the side streams of the precursor and the reactant can be achieved, enabling better removal and / or recycling of at least one of the precursor and the reactant.

[0046] In some embodiments, the precursor side stream line 122 is operably connected to the precursor trap 160. The precursor trap 160 can be constructed and arranged to remove unreacted precursors from the precursor side stream. Accordingly, it has the effect of being able to recover the precursors. In fact, in a semiconductor deposition apparatus such as an atomic layer deposition apparatus or a plasma enhanced atomic layer deposition apparatus, since only a part of the precursors used in the pulse, a considerable part of the precursors used can be wasted. Capturing the precursors in a precursor trap 160 such as a cold trap or an adsorption trap can be a countermeasure against the waste of precursors.

[0047] For example, a cold trap can condense or deposit reactive gases such as precursors and ALD by-products thereon, thereby removing them from the precursor side stream. For example, an adsorption trap can absorb and / or adsorb reactive gases such as precursors and ALD by-products to remove them from the precursor side stream.

[0048] In some embodiments, the system 100 includes a plurality of precursor traps 160, for example, two, three, four, five, six, or more precursor traps 160. The plurality of precursor traps 160 can be arranged in a mixed configuration including series, parallel, or both series and parallel arrangements. The plurality of precursor traps 160 can enhance precursor capture or increase the purity of the captured precursors by purification techniques such as fractional condensation.

[0049] In some embodiments, the captured precursors can be further purified, for example, by fractional distillation. The purification of the precursors can be performed, for example, on-site in a system according to an embodiment of the present disclosure. Alternatively, it can be performed near the system. Alternatively, the precursor purification can be performed at another location.

[0050] The substance captured by the precursor trap 160 can be stored in the precursor trap itself or removed by a specific type of removal device such as a drain. Additionally or alternatively, and in some embodiments, the system 100 can further include a collection well constructed and arranged to hold unreacted precursors captured by a cold trap.

[0051] In some embodiments, the substance captured by the precursor trap 160 can be configured to be processed and detoxified within a removal unit (not shown) that can be part of the described system 100, or can be placed at other locations such as, for example, on-site or off-site. Alternatively, the substance captured by the precursor trap 160 can also be provided to a precursor purification unit 167. The precursor purification unit 167 can include a recycled precursor pump (not shown) for pumping the purified precursor into the precursor source 120. The precursor purification unit 167 may be operably connected to the precursor trap 160 by a confined precursor line 169. The precursor purification unit 167 may be operably connected to the precursor supply source 120 by a purified precursor line 168 constructed 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 may be configured to include a fractional distillation apparatus. The fractional distillation apparatus may be configured to be constructed and arranged to purify unreacted precursors from the precursor trap. Thereby, a purified precursor stream can be obtained. In some embodiments, the fractional distillation apparatus is operably connected to the precursor source to provide at least a portion of the purified precursor stream to the precursor source.

[0052] In some embodiments, the reactant side flow line 132 is operably connected to the reactant trap 170. The reactant trap 170 may be configured to be constructed and arranged to remove unreacted reactants from the reactant side flow. This has the effect of enabling the recovery of reactants. In fact, in a semiconductor deposition apparatus such as an atomic layer deposition apparatus or a plasma enhanced atomic layer deposition apparatus, since only a part of the precursor used in the pulse is used, a considerable part of the precursor used can be wasted. Capturing the reactant in the reactant trap 170 such as a cold trap or an adsorption trap can be a countermeasure against the waste of the reactant. In some embodiments, the captured reactant can be further purified, for example, by fractional distillation. The purification of the reactant can be carried out in situ, for example, in a system according to an embodiment of the present disclosure. Alternatively, it can be carried out in the vicinity of the system. Alternatively, the purification of the reactant can be carried out at another location.

[0053] In some embodiments, the system 100 includes a plurality of reactant traps 170, for example, two, three, four, five, six, or more reactant traps 170. The plurality of reactant traps 170 can be arranged in a mixed configuration including series, parallel, or both series and parallel arrangements. The plurality of reactant traps 170 can enhance reactant capture.

[0054] In some embodiments, the system 100 described in the present disclosure may further include a purge gas recovery unit 180 and a recovered purge gas line 185. In some embodiments, the purge gas is N 2and includes at least one of the noble gases. Suitable noble gases may be selected from the group consisting of 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 recycled purge gas stream. The recovered purge gas line 185 may be configured to be operably connected to the purge gas recovery unit 180 for recycling the purge gas.

[0055] Also, exhaust gas can be passed from the reaction chamber through one or more precursor traps and / or reaction traps such as a sorption unit or a cold trap to remove various by-products, such as condensable by-products, unreacted precursors, and reactants from the gas phase and collect them for recycling or suitable disposal. The carrier gas exiting from one or more precursor traps may be of a purity high enough for reuse or recycle / upscaling (e.g., for performing further processes or for use in a nitrogen supply vacuum pump). The purity of a gas stream, such as a carrier gas stream, may be monitored, for example, by an in-line gas analyzer.

[0056] Recycling an inert gas stream, such as a carrier gas, can reduce the carbon footprint associated with unnecessary losses of process gas to the waste stream, extend the life of the scrubber, and reduce the cost of tool operation by reducing argon / nitrogen costs. Also, in some systems, the reaction chamber exhaust stream may be configured to be processed by a scrubber (which requires periodic replacement) before being released to the atmosphere as waste. Preventing this unnecessary loss of inert gases such as argon and nitrogen has great potential for carbon footprint and cost reduction. The resulting lower process gas requirements may also potentially reduce the tool footprint.

[0057] In some embodiments, the purge gas recovery unit 180 is fluidly connected to the reactant trap 170. Thus, at least a portion of the purge gas passing through the reactant trap 170 can be recovered into the purge gas recovery unit 180. For example, this fluid connection can be achieved by a reactant trap, i.e., a purge gas recovery unit line 172 provided with a corresponding check valve 173.

[0058] In some embodiments, the purge gas recovery unit 180 is fluidly connected to the precursor trap 160. Thus, at least a portion of the purge gas passing through the precursor trap 160 can be recovered into the purge gas recovery unit 180. For example, this fluid connection can be achieved by a precursor trap, i.e., a purge gas recovery unit line 162 provided with a corresponding check valve 163.

[0059] The system 100 according to the embodiment of FIG. 1 may be configured to include one or more pumps. For example, the system 100 may be configured to include a recovered purge gas pump 189 provided on the recovered purge gas line 185. The recovered purge gas pump 189 and any additional pumps can serve to provide the pressure gradient necessary for the gas to flow through the system 100. In some embodiments, the system 100 according to the embodiment of FIG. 1 further includes one or more of a precursor pump (not shown) and a reactant pump (not shown). The precursor pump may be configured and arranged to pump the purified precursor into the precursor source 120. The reactant pump may be configured and arranged to pump the purified reactant into the reactant source 130.

[0060] System 100 according to the embodiment of FIG. 1 may be configured to include an exhaust line 190. One or more exhaust lines 190 may be configured to provide at least a portion of the regenerated purge gas stream to the atmosphere or the decontamination system. The exhaust line 190 may be configured to be in fluid connection with the recovered purge gas line 185. The exhaust line 190 may be configured to include an exhaust valve 193, such as a check valve, that may be configured and arranged to prevent backflow of contaminants, such as atmospheric gas, into the system 100.

[0061] The regenerated purge gas line 185 may be configured to include a regenerated purge gas valve 183 that may be any suitable valve. The regenerated purge gas valve 183 may be configured to open to allow purge gas recycling or to close to prevent purge gas recycling. The regenerated purge gas valve 183 may be provided in the regenerated purge gas line 185 downstream of the exhaust line 190.

[0062] In some embodiments, the reactant purification unit 177 may be operably connected to the reactant source 130 by a purified reactant line 178 that is constructed and arranged to supply the purified reactant from the reactant purification unit 177 to the reactant source 130. Preferably, the reactant purification unit 177 may be configured to include a pump (not shown) that is constructed and arranged to send the purified reactant from the reactant purification unit 177 to the reactant source 130.

[0063] An embodiment of the purge gas recovery unit 300 will be described with reference to FIG. 3. In this embodiment, the purge gas recovery unit 300 includes a cold trap 310 and an adsorption unit 320 in series, and both the cold trap 310 and the adsorption unit 320 can suitably purify the used purge gas stream carried by the used purge gas stream line 315 to form a purified purge gas stream carried by the purified purge gas stream line 325. The cold trap 310 may be configured to be operably connected to the adsorption unit 320 by a partially purified purge gas stream line 316. The purified purge gas stream 325 can be used partially or wholly as the purge gas stream within the system according to an embodiment of the present disclosure. Additionally or alternatively, the purified purge gas stream 325 can be used partially or wholly for different purposes, for example, as the ballast gas in one or more pumps. Note that the cold trap may be configured to remove precursors and reaction products. Such a system may be effective in removing species having a low vapor pressure at the temperature of the cold trap, but can also have the effect of removing reaction by-products that are gaseous down to low temperatures by different means. Note that gases such as CH 4 , CO 2 , CO, O 2 etc. can be suitably removed using different systems such as an adsorption trap. A suitable adsorption trap may be configured with a porous adsorption medium that adsorbs gases that may be difficult to remove using a cold trap.

[0064] In some embodiments, the purge gas recovery unit described in the present disclosure may be configured with one or more scrubbers. Preferably, the scrubber may be configured with a reactive medium capable of reacting with at least one of the precursor and the reactant. Additionally, or alternatively, the purge gas recovery unit described in the present disclosure may be configured with two or more scrubbers that can be arranged in series, parallel, or a mixed configuration. For example, the purge gas recovery unit described in the present disclosure may be configured with a reactant scrubber and a precursor scrubber arranged in series. For example, the reactant scrubber may be arranged upstream of the precursor scrubber. For example, the precursor scrubber may be arranged upstream of the reactant scrubber. The reactant scrubber may be configured to include a reactive medium constructed and arranged to react with the reactant. The precursor scrubber may be configured to include a reactive medium constructed and arranged to react with the precursor. One or more scrubbers can be used in addition to, or in place of, one or more sorption traps.

[0065] Note that the scrubber and the sorption trap are known in the art per se.

[0066] Referring to FIG. 4, an embodiment of the system 400 according to the present disclosure is described in the present disclosure. The system 400 can preferably use cyclic gas phase processes such as atomic layer deposition, atomic layer etching, and plasma enhanced variants.

[0067] System 400 includes a precursor line 420 disposed with a precursor valve 421. The precursor valve 421 is constructed and arranged to open and close the precursor line 420. System 400 further includes a precursor purge gas line 425 disposed with a precursor purge gas valve 426. The precursor purge gas valve 426 is constructed 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 configured to merge into a junction precursor line 427 downstream of the precursor valve 421 and the precursor purge gas valve 426. The junction precursor line 427 is fluidly connected to the reaction chamber 410. In some embodiments, the junction precursor line 427 can be omitted, in which case the precursor line 420 and the precursor purge gas line 425 can be directly fluidly connected to the reaction chamber 410.

[0068] System 400 further includes a reactant line 430 disposed with a reactant valve 431. The reactant valve 431 is constructed and arranged to open and close the reactant line 430. System 400 further includes a reactant purge gas line 435 disposed with a reactant purge gas valve 436. The reactant purge gas valve 436 is constructed 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 configured to merge into a junction reactant line 437 downstream of the reactant valve 431 and the reactant purge gas valve 436. The junction reactant line 437 is fluidly connected to the reaction chamber 410. In some embodiments, the junction reactant line 437 may be omitted, in which case the reactant line 430 and the reactant purge gas line 435 can be directly fluidly connected to the reaction chamber 410.

[0069] As shown in the embodiment of FIG. 4, the system 400 described in the present disclosure may be configured with separate exhaust lines 440 and 450 for precursors and reactants, including a precursor exhaust line 440 and a reactant exhaust line 450. The precursor exhaust line 440 may be configured with a precursor exhaust valve 441. The reactant exhaust line 450 may be configured 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 in the present disclosure. Downstream of the precursor trap 460, a post-precursor trap valve 470 may be provided in the precursor exhaust line 440. Downstream of the reactant exhaust valve 451, the reactant exhaust line 450 may be in fluid connection with a pump 480. Similarly, downstream of the post-precursor trap valve 470, the precursor exhaust line 440 may be in fluid connection with the pump 480. The exhaust from the pump 480 may be configured to, for example, ventilate or be sent to a removal facility to process the reactants contained in the exhaust.

[0070] FIG. 5 shows an embodiment of a method for operating valves within the system 400 according to the embodiment of FIG. 4. In particular, FIG. 5 shows the open and closed positions during a precursor pulse 501, a precursor purge 502, a reactant pulse 503, and a reactant purge 504.

[0071] The precursor valve 421 first opens during the precursor pulse 501 and then closes during the precursor purge 502. The precursor purge gas valve 426 first closes during the precursor pulse 501 and then opens during the precursor purge 502. The precursor exhaust valve 441 is open 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.

[0072] The reactant valve 431 first opens during the reactant pulse 503 and then closes during the reactant purge 504. The reactant purge gas valve 436 first closes during the reactant pulse 503 and then opens during the reactant purge 504. The reactant exhaust valve 451 is open 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 efficiently trapped in the precursor trap 460 while minimizing the amount of reactant trapped in the precursor trap 460. This may be preferable as it allows minimizing or eliminating unwanted side effects between the precursor and the reactant in the precursor trap.

[0073] In some embodiments, the precursor can be recovered from the precursor trap 460. This can be done, for example, 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 facility for purifying the precursor, which is a known technique in itself.

[0074] Suitable precursors are known in the art. 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 can include Group IV elements such as silicon or germanium.

[0075] Suitable reactants can be, for example, a composition comprising one or more oxygen reactants selected from H 2 O, O 2 and O 3 .

[0076] Suitable reactants can be, for example, a composition comprising one or more carbon reactants selected from CO and CO 2 .

[0077] Suitable reactants may include, for example, NH 3 , N 2 O, NO, NO 2 , and NO 3 and may be configured to include nitrogen reactants selected from.

[0078] Suitable reactants may be configured to include hydrogen reactants, such as H 2 .

[0079] Suitable purge gases may be gases such as N 2 and noble gases. Suitable noble gases may include He, Ne, Ar, Kr, and Xe.

[0080] In some embodiments, it will be understood that the plurality of systems described may be configured to be included in a semiconductor processing facility. In such embodiments, the plurality of systems may be configured to be operably connected to a central abatement facility. The central abatement facility may comprise at least one of one or more central purge gas purification units, one or more central precursor purification units, and a plurality of central reactant purification units. At least one of the central purge gas purification unit, the central precursor purification unit, and the central reaction purification unit may be configured to be operably connected to two or more systems as described in the present disclosure. Thus, at least one of the purge gas, precursor, and reactant from the plurality of systems can be purified by a single purification unit.

Claims

1. 1. A system comprising: A reaction chamber; a precursor source comprising a precursor, the precursor source being operably connected to the reaction chamber by a precursor line, the precursor line being disposed with a precursor valve operable to open and close the precursor line; a reactant source including a reactant, the reactant source being operably connected to the reaction chamber by a reactant line, the reactant line being disposed 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 arranged with a precursor side stream valve operable to open and close the precursor side stream line; a reactant side stream line constructed and arranged to remove a reactant side stream from a reaction chamber, the reactant side stream line being arranged with a reactant side stream valve operable to open and close the reactant side stream line.

2. 10. The system of claim 1, further comprising a controller, the controller comprising a memory having computer readable instructions stored thereon that, 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. 10. The system of claim 1, further comprising a controller, the controller comprising a memory having computer readable instructions stored thereon that, when executed, cause the system to open the reactant lines, close the precursor lines, open the reactant side stream lines, and close the precursor side stream lines.

4. The method further comprises: providing a controller comprising: a memory having computer readable instructions stored thereon that, when executed, cause the system to perform a cyclic deposition process, the cyclic deposition process comprising a plurality of cycles, each cycle of the plurality of cycles comprising a precursor pulse and a reactant pulse; the precursor pulse is configured to include opening the precursor line, closing the reactant line, opening the precursor side stream line, and closing the reactant side stream line, thereby supplying the precursor to the reaction chamber and removing the precursor side stream from the reaction chamber via the precursor side stream line; 2. The system of claim 1, wherein the reactant pulse is configured to include opening the reactant line, closing the precursor line, opening the reactant side stream line, and closing the precursor side stream line, thereby supplying the reactant to the reaction chamber and removing the reactant side stream from the reaction chamber via the reactant side stream line.

5. 5. The system of claim 1, further comprising a purge gas source comprising a purge gas, the purge gas source operably connected to the reaction chamber by a purge gas line, the purge gas line comprising one or more purge gas valves operable to open and close the purge gas line.

6. The cyclic deposition process further includes a post precursor purge and a post reactant purge; the post precursor purge is performed after a precursor pulse and includes opening the purge gas line, opening the precursor side stream line, closing the precursor line, closing the reactant line, and closing the reactant side stream line; 6. The system of claim 5, wherein the post reactant purge is performed after a reactant pulse and includes opening the purge gas line, opening the reactant side stream line, closing the precursor line, closing the reactant line, and closing the precursor side stream line.

7. 5. The system of claim 1, wherein the precursor side stream line is operatively connected to a precursor trap, the precursor trap constructed and arranged to remove unreacted precursor from the precursor side stream.

8. 5. The system of claim 1, wherein the reactant side stream line is operatively connected to a reactant trap, the reactant trap constructed and arranged to remove unreacted reactants from the reactant side stream.

9. Further comprising a purge gas recovery unit and a recovery purge gas line; the purge gas recovery unit is constructed and arranged to recover spent purge gas from at least one of the reactant side stream and the precursor side stream, thereby obtaining a recovered purge gas stream; The system of claim 7 , wherein the recovered purge gas line operatively connects the purge gas recovery unit to a purge gas source for recycling purge gas.

10. The purge gas is N ２ , H ２ 10. The system of claim 9, comprising at least one of:

11. The system of claim 7 , wherein the precursor trap comprises a cold trap.

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

13. The system of claim 7 , wherein the precursor trap comprises a sorption trap.

14. 10. The system of claim 7, further comprising a fractional distillation apparatus, said fractional distillation apparatus constructed and arranged to purify unreacted precursor from said precursor trap, thereby obtaining a purified precursor stream.

15. 15. The system of claim 14, wherein the fractional distillation apparatus is operatively connected to the precursor source and configured to provide at least a portion of the purified precursor stream to the precursor source.

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