Substrate processing apparatus and method

Abstract

A substrate processing apparatus (100) comprising, a reaction chamber (110) for processing at least one substrate (120), a foreline (150) for removing processing fluid from the reaction chamber (110), a valve (200), comprising an actuator (260) to adjust the valve (200), arranged in the foreline (150) for controlling flow of the processing fluid, the first fluid flow (F1), through the valve (200), wherein the valve (200) is configured to provide a deliberate leak of cleaning gas, second fluid flow (F2), from the actuator (260) into the valve (200)

Description

[0001] SUBSTRATE PROCESSING APPARATUS, VALVE AND METHOD

[0002] TECHNICAL FIELD

[0003] The present disclosure generally relates to controlling fluid flow for substrate processing. The disclosure relates particularly, though not exclusively, to valves for controlling fluid flow.

[0004] BACKGROUND

[0005] This section illustrates useful background information without admission of any technique described herein representative of the state of the art.

[0006] In surface processing, such as atomic layer deposition, ALD, precursors are injected into a reaction chamber to be deposited on a substrate. With certain reaction chemistries, it may be beneficial or required to increase the residence time of the precursors within the reaction chamber to improve processing quality. However, increased residence time and delayed removal of processing gases also increases the risk of contamination and undesired accumulation of the precursors on the surfaces of the substrate processing apparatus and its components that are in contact with the precursors. Such a contamination may reduce processing quality, increase need for maintenance and reduce lifetime of the components of the substrate processing apparatus.

[0007] There is a need for components for substrate processing apparatus with improved resistance to undesired precursor deposition and reliability to operate even in harsh conditions with high risk of contamination.

[0008] SUMMARY

[0009] The appended claims define the scope of protection. Any examples and technical descriptions of apparatuses, products and / or methods in the description and / or drawings not covered by the claims are presented not as embodiments of the invention but as background art or examples useful for understanding the invention.

[0010] It is an object of the present invention to provide a substrate processing apparatus comprising valve in a foreline, and such a valve, with improved resistance to contamination and increased reliability, or at least provide an alternative to existing solutions. According to a first example aspect there is provided a substrate processing apparatus, comprising: a reaction chamber for processing at least one substrate; a foreline for removing processing fluid from the reaction chamber; a valve, comprising an actuator to adjust the valve, arranged in the foreline for controlling flow of the processing fluid, a first fluid flow, through (a valve flow channel of) the valve, wherein the valve is configured to provide a deliberate leak of cleaning gas, second fluid flow, from the actuator into (the valve flow channel of) the valve.

[0011] Advantageously, cleaning of internal parts of the valve may be improved. Further, valve reliability and lifetime may be increased. Further, residence time of processing fluid within the reaction chamber may be simply controlled by adjusting the valve. Accordingly, the reaction chamber and control means upstream of the valve may be kept simple.

[0012] In certain embodiments, the cleaning gas is inert gas ora mixture of two or more inert gases. Advantageously, undesired reactions between the first fluid flow and the second fluid flow may be minimized. Further, cleaning efficacy may be improved.

[0013] In certain embodiments, the actuator is configured to provide the second fluid flow into the valve (simultaneously) when adjusting the valve. Advantageously, cleaning and protection from contamination may be provided when the risk of undesired deposition is highest when the valve is in use or adjusted. Contamination may include unwanted deposition of the processing fluids on the valve decreasing valve operation and increasing the need to replacement / maintenance.

[0014] In certain embodiments, the actuator is a pneumatic actuator. In certain embodiments, the actuator is actuatable by pneumatics alone. Advantageously, further control mechanisms, such as springs, may not need to be arranged to control the actuator. Therefore, the actuator and the valve may be kept compact.

[0015] In certain embodiments, the actuator is actuatable by pneumatics and a spring element. In certain embodiments, the spring element is a spring. In certain embodiments, a spring element is arranged to operate against the pneumatic actuation. In certain embodiments, the actuator is actuated pneumatically to open the valve and actuated by a spring element to close the valve (spring-closable pneumatic actuator). In certain embodiments, the actuator is actuated pneumatically to close the valve and actuated by a spring element to open the valve (spring-openable pneumatic actuator). Advantageously, robust and reliable valve mechanism may be used. Further, pneumatic control may be kept more simple. In certain embodiments, the actuator is configured to use the cleaning gas as a pneumatic gas. Advantageously, gas usage may be simplified as same gas is usable for both cleaning and as pneumatic gas. Further, the actuator may also be cleaned by the cleaning gas.

[0016] In certain embodiments, the valve comprises a leak path for providing the deliberate leak of the second fluid flow through the actuator into the valve. Advantageously, the valve may be kept compact as separate cleaning gas line is not needed to provide the second fluid flow. Further, additional control of the second fluid flow b the actuator is enabled.

[0017] In certain embodiments, the valve comprises a closure member which is movable by the actuator (to adjust the valve) and arranged at least partially within the actuator, wherein the leak path is defined at least partially by the movable closure member. Advantageously, the closure member cleaning may be improved and the closure member effectively protected from undesired deposition.

[0018] In certain embodiments, the closure member comprises perforations, the perforations being configured to form a part of the leak path. Advantageously, wear and tear of the valve may be reduced as loosely fitting components may be avoided since the flow path does not always need to be arranged around the closure member. Further, operation of the actuator may be ensured while enabling the continuous flow path through the actuator.

[0019] In certain embodiments, the valve (200) is manufactured (entirely) of metal or metal alloys. Advantageously, the valve may be heated and the valve may endure and reliably operate at high or extreme temperatures, such as temperatures above 200°C, above 500°C, above 650 °C or even up to 1000 °C.

[0020] In certain embodiments, the substrate processing apparatus comprises a pilot valve configured to control the second fluid flow to the actuator. Advantageously, the deliberate leak of cleaning gas may be further controlled, or switched on or off, regardless of the operation of the actuator.

[0021] According to a second example aspect there is provided a valve, comprising:

[0022] (a valve flow channel for providing flow path for first fluid flow through the valve;) an actuator for adjusting the valve configured to control first fluid flow through (the valve flow channel of) the valve; wherein the valve is configured to provide a deliberate leak of cleaning gas, second fluid flow, from the actuator into (the valve flow channel of) the valve.

[0023] Advantageously, the undesired contamination of the valve may be reduced. According to a third example aspect there is provided a method for operating a valve, comprising: receiving first fluid flow into (a valve flow channel of) the valve; adjusting the valve by an actuator to control the first fluid flow through (the valve flow channel of) the valve; and providing a deliberate leak of cleaning gas, a second fluid flow, from the actuator into (the valve flow channel of) the valve.

[0024] In certain embodiments, the method further comprises: providing the valve in a foreline of a substrate processing apparatus; and providing the first fluid flow from the substrate processing apparatus to the valve through the foreline.

[0025] In certain embodiments, the actuator is pneumatic actuator, the method further comprising: using the second fluid flow as pneumatic gas.

[0026] In certain embodiments, the method further comprises: providing the second fluid flow into (the valve flow channel of) the valve from the actuator when adjusting the valve.

[0027] Different non-binding example aspects and embodiments have been illustrated in the foregoing. The embodiments in the foregoing are used merely to explain selected aspects or steps that may be utilized in different implementations. Some embodiments may be presented only with reference to certain example aspects. It should be appreciated that corresponding embodiments may apply to other example aspects as well.

[0028] BRIEF DESCRIPTION OF THE FIGURES

[0029] Some example embodiments will be described with reference to the accompanying figures, in which:

[0030] Fig. 1 schematically shows a substrate processing apparatus according to certain embodiments;

[0031] Fig. 2 schematically shows a cross-sectional side view of a valve according to certain embodiments;

[0032] Fig. 3 schematically shows a valve according to certain embodiments; Figs. 4-6 schematically show cross-sectional side views of a valve according to certain embodiments; and

[0033] Fig. 7 shows a flow chart of a method according to certain embodiment.

[0034] DETAILED DESCRIPTION

[0035] In the following description, like reference signs denote like elements or steps.

[0036] In certain embodiments, as described herein, is provided a substrate processing apparatus comprising a self-cleaning valve in a foreline, wherein the valve is configured to provide a deliberate leak of cleaning gas into the valve. In certain embodiments, a self-cleaning valve is provided. In certain embodiments, a related method is provided.

[0037] Substrate processing apparatuses, or surface deposition apparatuses, in the context of the present disclosure are configured to exploit principles of vapor-deposition based techniques. In preferred embodiments, the substrate processing apparatus is an ALD apparatus. As used herein, the term ALD comprises all applicable ALD based techniques and any equivalent or closely related technologies, such as, for example the following ALD sub-types: MLD (Molecular Layer Deposition), plasma-assisted ALD, such as PEALD (Plasma Enhanced Atomic Layer Deposition) and photon-enhanced Atomic Layer Deposition (known also as flash enhanced ALD).

[0038] The skilled person is aware of the principles of ALD. In ALD, at least one substrate is typically exposed to temporally separated precursor pulses in a reaction vessel to deposit material on the substrate surfaces by sequential self-saturating surface reactions.

[0039] In further embodiments, the substrate processing apparatus is applied to other deposition technologies, such as Physical Vapor Deposition (PVD) and for Plasma-Enhanced Chemical Vapor Deposition (PECVD) processes.

[0040] In certain embodiments, the substrate processing apparatus is an atomic layer etching (ALE) apparatus.

[0041] As used herein, fluid may refer to a liquid or a gas, or a combination thereof. However, in the context of the present disclosure, fluids are preferably gaseous substances, comprising precursor chemical(s), (inert) carrier gas(es) and / or purging gas(es) used in substrate processing. A substrate processing apparatus comprising a valve in a foreline according to certain embodiments is depicted in Fig. 1. In certain embodiments, the apparatus 100 is an ALD apparatus.

[0042] In certain embodiments, the apparatus 100 comprises a reaction chamber 110. The reaction chamber 110 defines a processing volume 115 in which one or more substrates 120 may be processed.

[0043] In certain embodiments, the apparatus 100 is configured to deposit thin films onto substrate surfaces. For instance, films deposited by ALD are uniform, dense and pinhole-free.

[0044] In certain embodiments, the apparatus 100 is configured to process one substrate 120. In certain embodiments, the apparatus 100 is configured to process a plurality of substrates 120 simultaneously. In certain embodiments, the apparatus 100 is configured to process at least one stack of substrates 120. The one or more substrates 120 may be arranged onto or into a substrate support 130 within the processing volume 115. The substrate support may be or comprise or be configured to receive a cassette or a holder arranged to accommodate the one or more substrates 120. Alternatively, the cassette or holder may be integrated or arranged within an outer chamber space at least partially surrounding the reaction chamber 110 and be movable between the outer chamber space and the reaction chamber 110. The cassette or holder may be further integrated with a lid of a reaction chamber. The substrates may be, for instance, wafers.

[0045] In certain embodiments, the apparatus 100 comprises a substrate support 130. The substrate support 130 is configured to support the one or more substrates 120 during substrate processing. In certain embodiments, the substrate support 130 is movable. In certain embodiments, the substrate support 130 is in the form of a support table.

[0046] In certain embodiments, the apparatus 100 comprises one or more processing fluid source 140. The one or more processing fluid sources are configured to provide processing fluids to the processing volume 115. Processing fluids may comprise reaction precursors, plasma precursors, plasma, cleaning gas or purge gas. Below the processing fluid is also referred to as first fluid flow F1 with respect to Figs. 2-7.

[0047] In certain embodiments, the apparatus 100 comprises a foreline 150. Processing fluids are removed from the processing volume 115 through the foreline 150. In certain embodiments, the apparatus 100 comprises a vacuum pump 155. In certain embodiments, the foreline 150 is connected to the vacuum pump 155. Advantageously, removal of processing fluids through the foreline 150 may be enhanced by the vacuum pump 155.

[0048] In certain embodiments, the apparatus comprises a valve 200 in the foreline 150. In certain embodiments, the valve 200 is coupled to the foreline 150. In certain embodiments, the valve 200 is arranged to the foreline 150. In certain embodiments, the foreline 150 comprises the valve 200. In certain embodiments, the valve 200 is configured to control fluid flow through the foreline 150. Advantageously, residence time of processing fluids within the processing volume 115 and the removal of the processing fluids through the foreline 150 may be controlled by simply adjusting the valve 200. Consequently, flow control upstream of the valve may be kept simple.

[0049] In certain embodiments, the valve 200 in the foreline 150 is a self-cleaning valve. In certain embodiments, the valve 200 is configured to provide a deliberate leak of cleaning gas, the second fluid flow F2, into the valve. In certain embodiments, the valve 200 is configured to provide a deliberate leak of cleaning gas into the valve to clean internal surfaces of the valve. In certain embodiments, the valve 200 is configured to provide a deliberate leak of cleaning gas into the valve to clean sealing surfaces (of a movable closure member and a corresponding valve seat) of the valve. In certain embodiments, the valve 200 is configured to provide a deliberate leak of cleaning gas into the valve to clean valve seat. Advantageously, undesired deposition of processing fluids or reactants may be prevented or at least reduced. Furthermore, internal surfaces of the valve may be cleaned without dismantling the valve. Still further, lifetime and reliability of the valve may be increased.

[0050] In certain embodiments, the valve 200 is configured to provide the deliberate leak of cleaning gas into the valve from an actuator (not shown in Fig. 1) of the valve 200. In certain embodiments, the valve 200 is configured to provide the deliberate leak of cleaning gas into the valve through the actuator of the valve 200. In certain embodiments, the valve 200 is configured to provide the deliberate leak of cleaning gas through the actuator of the valve 200 to clean valve seat 250 when the actuator moves the movable closure member of the valve. In certain embodiments, the actuator is pneumatic actuator. In certain embodiments, the actuator is actuatable by pneumatics and a spring element 270. In certain embodiments, the actuator is configured to use the cleaning gas as pneumatic gas. Advantageously, the valve may be cleaned with the cleaning gas simultaneously while operating the valve. In certain embodiments, the cleaning gas is inert gas. In certain embodiments, the cleaning gas is inert gas mixture. Herein inert gas or inert gas mixture refers to a gas or a gas mixture that does not react or reacts only slowly with components of the first fluid flow. In certain embodiments, the cleaning gas is N2 or ultra-high purity nitrogen gas, UHP N2. In certain embodiments, the cleaning gas is Ar, He, or other noble gas. In certain embodiments, the cleaning gas is a mixture of two or more noble gases. However, other cleaning gases may be used as well. Note that below with respect to Figs. 2-6, the cleaning gas is referred to as second fluid flow F2.

[0051] In certain embodiments according to Fig. 1 , the apparatus 100 comprises a cleaning gas source 160. In certain embodiments, the valve 200 is connected to the cleaning gas source 160. The cleaning gas source 160 is configured to provide the cleaning gas (second fluid flow F2) to the valve 200. In certain embodiments, the cleaning gas source 160 is configured to provide the cleaning gas (second fluid flow F2) to the valve 200 through the actuator of the valve.

[0052] In certain embodiments, the apparatus 100 comprises a pilot valve 170. In certain embodiments, the pilot valve is located (in a cleaning gas line) between the valve 200 and the cleaning gas source 160. In certain embodiments, the pilot valve 170 is configured to control the cleaning gas flow from the cleaning gas source 160 to the valve 200. In certain embodiments, the pilot valve 170 is configured to control the cleaning gas flow to the actuator of the valve 200. In certain embodiments, the pilot valve 170 is a compressed / clean dry air, CDA, operated pneumatic pilot valve. In certain embodiments, the pneumatic gas for operating the pilot valve is provided from a pilot valve pneumatic source 175. Advantageously, control of the cleaning gas delivery to the valve 200 may be improved. When needed, cleaning gas delivery may also be stopped by the pilot valve (for example, during substrate processing stage, when the valve 200 is configured to fully close the foreline), i.e. , the valve 200 may be operated also without cleaning gas bleed.

[0053] In general, the valve 200 in the foreline enables simple control of processing fluid residence time within the processing volume 115 (by adjusting the flow through the foreline by the valve). Advantageously, the deliberate leak may provide reduced valve contamination and longer lifetime of the valve. Further, delivering the cleaning gas through the actuator may also improve cleaning of the actuator. The components and operation of the valve 200 will be discussed in more detail below with respect to Figs. 2-6.

[0054] Fig. 2 schematically shows a cross-sectional side view of the valve 200 according to certain embodiments. Fig. 3 schematically shows the valve 200 according to certain embodiments viewed from outside.

[0055] In certain embodiments, the valve 200 is arranged in a foreline 150 downstream of a processing volume 115 of a substrate processing apparatus 100. In certain embodiments, the valve 200 is configured to control the fluid flow from the processing volume 115 through the foreline 150.

[0056] The valve 200 comprises a valve body 210. The valve body 210 is configured to provide the outer casing for the valve 200. The valve 200 is configured to comprise valve internal parts within the valve body 210.

[0057] The valve 200 comprises a first inlet 220. The first inlet 220 is for providing first fluid flow F1 to the valve 200. The valve 200 is configured to receive first fluid flow F1 to the valve 200 through the first inlet 220. In certain embodiments, the first fluid flow F1 comprises processing fluid removed from the processing volume of the substrate processing apparatus 100. In certain embodiments, the foreline 150 of a substrate processing apparatus 100 is coupled to the first inlet 220. In certain embodiments, the foreline 150 is configured to provide processing fluid removed from the processing volume 115 of the substrate processing apparatus 100 (i.e. , the first fluid flow F1) to the valve 200 through the first inlet 220.

[0058] The valve 200 comprises an outlet 230. The outlet is for removing fluid from the valve 200. In certain embodiments, the outlet 230 is connected to a vacuum pump 155. In certain embodiments, the outlet 230 is configured to provide an output flow F3 from the valve 200. In certain embodiments, the output flow F3 comprises the first fluid flow F1. In certain embodiments, the output flow F3 comprises a second fluid flow F2. In certain embodiments, the output flow F3 is a mixture of the first fluid flow F1 and the second fluid flow F2.

[0059] In certain embodiments, the valve 200 comprises a valve flow channel 215 within the valve 200. The valve flow channel 215 is the path (or volume) through the valve 200 from the first inlet 220 to the outlet 230. In certain embodiments, the first fluid flow F1 is configured to propagate through the valve 200 from the first inlet 220 along the valve flow channel 215 to the outlet 230. In certain embodiments, the valve flow channel 215 is at least partially defined by (inside of) the valve body 210.

[0060] The valve 200 comprises valve internal parts, or valve trim. The valve internal parts are the functional parts of the valve 200 configured to control the first fluid flow F1 through the valve 200. In certain embodiments, the valve internal parts comprise the parts of the valve 200 exposed to the first fluid flow F1. In certain embodiments, the valve internal parts comprise the movable or replaceable parts of the valve 200 exposed to the first fluid flow F1 . In certain embodiments, the valve internal parts comprise at least a movable closure member 240 and a valve seat 250.

[0061] In certain embodiments, the valve 200 comprises the movable closure member 240. The closure member 240 is arranged to be movable (at least partially) within the valve flow channel 215. The valve 200 is configured to adjust the position of the closure member 240 to control the first fluid flow F1 through the valve 200. In certain embodiments, the valve flow channel 215 is at least partially defined by the closure member 240.

[0062] In certain embodiments, the closure member 240 comprises a sealing element 246. The sealing element 246 comprises a sealing surface. In certain embodiments, the sealing element 246 of the closure member 240 is arranged to reside at least partially within the valve flow channel 215. In certain embodiments, the sealing element 246 is configured to move within the valve flow channel 215 when the closure member 240 is moved.

[0063] In certain embodiments, the valve comprises the valve seat 250. In certain embodiments, the valve seat 250 is located within the valve flow channel 215. In certain embodiments, the valve flow channel 215 is partially defined by the valve seat 250.

[0064] In certain embodiments, the valve seat 250 is made of metal or metal alloy. In certain embodiments, the valve seat comprises PTFE. In certain embodiments, the valve seat 250 comprises thermoplastic polymer. In certain embodiments, the valve seat comprises elastomer.

[0065] The sealing surface of the sealing element 246 is configured to match the valve seat 250. In certain embodiments, the valve 200 is configured to prevent the first fluid flow F1 through the valve flow channel 215 when the sealing element 246 of the movable closure member 240 is arranged against the valve seat 250. Accordingly, the valve 200 may be closed by bringing the closure member 240 in contact with the valve seat 250. That is, in certain embodiments, the valve 200 is configured to prevent the first fluid flow F1 through the valve flow channel 215 by arranging the closure member 240 against the valve seat 250.

[0066] In certain embodiments, the sealing element 246 is shaped as a wedge, ball, plug, or disc. In certain embodiments, the sealing element comprises metal or metal alloy. In certain embodiments, the sealing element 246 is metallic. Advantageously, particularly metallic sealing element endures heating to high temperatures. Further, O-rings may not be needed to seal the contact between the sealing element 246 and the valve seat 250.

[0067] In certain embodiments, the sealing element 246 or sealing surface of the sealing element 246 comprises polytetrafluoroethylene, PTFE.

[0068] In certain embodiments, the valve 200 is manufactured fully of metal or metal alloys. In certain embodiments, the valve is manufactured of stainless steel, such as alloy 316L. In certain embodiment, the valve is at least partially manufactured of nickel-chromium-based metal alloys, such alloys commercially known as Hastelloy or Inconel. In certain embodiments, the valve is manufactured at least partially of Fe-Cr alloys of steels and stainless steels, Fe-Cr-Ni alloys of stainless steels and special steels, Ni base alloys, FeCrAI alloys, FeCrNi alloys, Ti alloys and Ta, Hf, Zr alloys. Advantageously, the fully metal structure of the valve enables the valve to withstand temperatures limited by the service temperature of the metal and not limited to service temperatures limited by elastomer sealings. Accordingly, the valve may endure high temperatures, such as above 200 °C, above 500 °C, above 650 °C, or even up to 1000 °C. Furthermore, the valve may be more reliable also in harsh conditions involving the high temperatures.

[0069] In certain embodiments, the valve 200 comprises a backseat 255 for the closure member 240. In certain embodiments, the valve 200 comprises a backseat 255 for the sealing element 243 of the closure member 240. In certain embodiments, the closure member 240 or the sealing element 243 is configured to rest against the backseat 255 when the valve flow channel 215 is fully open to allow the first fluid flow F1 to pass through the valve 200.

[0070] In certain embodiments, the closure member 240 comprises a stem (or rod) 243. In certain embodiments, the sealing element 246 is attached to a first end of the stem 243. In certain embodiments, the sealing element 246 and the stem 243 can be decoupled from each other. Advantageously, assembly and dismantling of the valve 200, for example, for maintenance or replacement of parts may be facilitated. In certain embodiments, the valve 200 comprises an actuator 260. The actuator 260 is configured to move the movable closure member 240 within the valve body 210. In certain embodiments, the actuator is configured to form a part of the valve body 210. In certain embodiments, the actuator 260 is a pneumatic actuator.

[0071] In certain embodiments, the actuator 260 comprises an actuator chamber 265. The actuator chamber 265 is configured to at least partially house the stem 243 of the closure member 240. In certain embodiments, the stem 243 of the closure member 240 is configured to movably reside at least partially within the actuator chamber 265. In certain embodiments, the actuator chamber 265 is configured to extend and continue within the valve body 215 towards the valve flow channel 215. In certain embodiments, the actuator chamber 265 is defined by (body of) the actuator 265. In certain embodiments, the actuator chamber 265 is defined at least partially by (body of) the actuator 265. In certain embodiments, the actuator chamber 265 is at least partially defined by the valve body 210.

[0072] In certain embodiments, the stem 243 of the closure member 240 is configured to be movable within the actuator chamber 265. In certain embodiments, the stem 243 of the closure member 240 is configured to be pneumatically movable within the actuator chamber 265. In certain embodiments, the valve 200 is configured to close the valve 200 (the valve flow channel 215) by pneumatically moving the closure member 240 by the actuator 260.

[0073] In certain embodiments, the valve 200 comprises a spring element 270. In certain embodiments, the spring element 270 is configured to resist (or operate against) the pneumatically driven actuation of the closure member 240 of the actuator 260. In certain embodiments, the spring element 270 is configured to push against the pneumatically driven actuation of the closure member 240, for example, as depicted in Fig. 2. In certain embodiments, the spring element 270 is configured to pull against the pneumatically driven actuation of the closure member 240, for example, as depicted in Figs. 4-6. Whether the spring element 270 is configured to push or pull may depend on which parts of the valve 200 the spring element is coupled to and the relative movement directions of those parts.

[0074] In certain embodiments, the spring element 270 is configured to move the closure element towards a position in which the valve flow channel 215 is fully open. In certain embodiments, the spring element 270 is configured to move the sealing element 246 towards the backseat 255. In certain embodiments, the valve 200 is a spring-openable valve, wherein pneumatic gas pressure is needed to overcome the spring to move the closure member 240. That is, the spring element 270 is configured to keep the valve 200 fully open, unless pneumatic actuation is provided to fully or partially close the valve 200. Advantageously, active pneumatic control may only be needed in one direction to (partially) close the valve 200. Upon removal of the pneumatic actuation, the valve may be opened by the spring element 270. Accordingly, the valve control may be kept simple. Furthermore, risk of failure of the valve or valve components may be reduced.

[0075] In certain embodiments, the spring element 270 is configured to move the closure element towards a position in which the valve flow channel 215 is fully closed. In certain embodiments, the spring element 270 is configured to move the sealing element 246 towards the valve seat 250. In certain embodiments, the valve 200 is a spring-closable valve, wherein pneumatic gas pressure is needed to overcome the spring to move the closure member 240. That is, the spring element 270 is configured to keep the valve 200 fully closed, unless pneumatic actuation is provided to fully or partially open the valve 200. Advantageously, active pneumatic control may only be needed in one direction to (partially) open the valve 200 and the pneumatic means may be kept simpler.

[0076] In certain embodiments, the spring element 270 is coupled to at least the closure member 240. In certain embodiments, the spring element 270 is coupled to the stem of the closure member 240. In certain embodiments, the spring element is coupled to the actuator 260. In certain embodiments, the spring element is coupled to the valve body 215. In certain embodiments, the spring element 270 is located within the actuator 260. In certain embodiments, the spring element 270 is located within the actuator chamber 265.

[0077] In certain embodiments, the spring element 270 is a spring. In certain embodiments, the spring is metallic. Advantageously, the valve may be heated without damaging the spring element 270. Further, simple spring may be feasibly replaced and spare parts easily produced.

[0078] The actuator 260 comprises a second inlet 280. The second inlet 280 is configured to receive a second fluid flow F2 to the actuator 260.

[0079] In certain embodiments, the second inlet 280 is connected to a cleaning gas source 160. The cleaning gas flow from the cleaning gas source 160 to the actuator 260 may be controlled by a pilot valve 170. In certain embodiments, the second fluid flow F2 comprises cleaning gas. In certain embodiments, the second fluid flow F2 is a cleaning gas flow. In certain embodiments, the second fluid of the second flow F2 is inert gas. In certain embodiments, the second fluid of the second fluid flow F2 is ultra-high purity nitrogen gas, UHP N2.

[0080] The valve 200 is configured to provide the second gas flow F2, which preferably is inert cleaning gas glow, from the second inlet 280 through the actuator 260 to the valve flow channel 215.

[0081] In certain embodiments, the valve 200 comprises a leak path from the second inlet 280 through the actuator 260 to the valve flow channel 215. In certain embodiments, the leak path is configured to provide the second fluid flow F2 to the valve flow channel 215. In certain embodiments, the leak path is configured to provide the second fluid flow F2 to the valve flow channel 215 simultaneously with the first fluid flow F1.

[0082] In certain embodiments, the valve is configured to receive both first fluid flow F1 and the second fluid flow F2 in the valve flow channel 215. In certain embodiments, the valve is configured to receive both first fluid flow F1 and the second fluid flow F2 simultaneously in the valve flow channel 215.

[0083] In certain embodiments, the leak path is at least partially defined by the actuator 260. In certain embodiments, the leak path is at least partially defined by the actuator chamber 265. In certain embodiments, the leak path is defined at least partially by the closure member 240. In certain embodiments, the valve 200 is configured to comprise a volume (or volumes) between an outer surface of the closure member 240 and the inner surface of the actuator chamber 265 to form the leak path. In certain embodiments, the leak path is defined at least partially as the volume between an internal surface of the actuator chamber (265) and an outer surface of the closure member (240)

[0084] In certain embodiments, the leak path further comprises the volume(s) between the closure member 240 and the back seat 255. In certain embodiments, the leak path comprises the volume(s) between the closure member 240 and the inside walls of the valve flow channel 215. Advantageously, a deliberate leak (or bleed) of second fluid flow F2, a cleaning gas, may be provided from around the circumference of the closure member 240 to the valve flow channel 215. Advantageously, the closure member 240 and valve flow channel 215 may be effectively cleaned with the cleaning gas while operating the valve 200. Further, cleaning gas flow from around the circumference of the closure member 240 is effectively delivered and guided also the valve seat 250 and the backseat 255 when moving the closure member 240 in proximity of said seats 250, 255. Furthermore, cleaning gas flow provided through the leak channel may also effectively prevent or at least decrease deposition of first fluid flow chemicals, such as processing fluids from a substrate processing apparatus 100, onto the internal surfaces of the valve 200.

[0085] In certain embodiments, the actuator 260 is a pneumatic actuator. In certain embodiments, the actuator 260 is configured to operate with the cleaning gas of the second fluid flow F2 as pneumatic gas. That is, the second fluid flow F2 is configured to actuate the closure member 240 at least partially housed within the actuator chamber 265. The second fluid of the second fluid flow F2 is preferably cleaning gas, more preferably UHP N2. Advantageously, separate pneumatic gas may not be needed, and the valve and actuator may be kept more compact. Furthermore, cleaning of the inside of the actuator may also be improved.

[0086] In certain embodiments, the actuator 250 is actuatable by pneumatics and the spring element 270. In certain embodiments, the spring element 270 is arranged to act against the pneumatic actuation. For instance, the valve may be openable by pneumatics and closable by the spring element, or vice versa.

[0087] In certain embodiments, the stem 243 of the closure member240 housed within the actuator chamber 265 comprises perforations 241 . The perforations 241 are configured to provide a leak path through the respective part of the closure member 240 wherein they are located. For example, in embodiments according to Fig. 2, the perforations 241 are located in the bottom part of the stem 243 which is the part of the closure member 240 which is configured to first encounter the second fluid flow F2 received through the second inlet 280.

[0088] The perforations 241 may be provided in addition or as an alternative to a local section of the leak path arranged around the circumference of the respective part of the stem 243. In certain embodiments, the perforations 241 are configured to enable passage of the second fluid flow F2 through the actuator 260. Advantageously, a continuous leak path through the actuator may be formed without significantly needing to adjust to the dimensions of the actuator 260 or actuator chamber 265. Further, tight and accurate fit of the stem to the actuator chamber can be ensured while enabling the continuous leak path, thus, loosely fitting components may be avoided and related additional wear and tear reduced. Further, maximum conductance of the leak path may be at least partially controlled by the number and / or size of the perforations arranged in the stem 243.

[0089] Operation of the valve 200 and adjustment of the closure member position is described in more detail related to Figs. 4-6. Figs. 4-6 depict a valve comprising the closure member 240 adjusted to different positions to regulate the first fluid flow F 1 through the valve flow channel 215. At the same time, movement and / or position of the closure member 240 affect the second fluid flow F2 provided from the actuator 260.

[0090] Fig. 4 depicts the valve 200 according to certain embodiments in a fully open configuration. That is, the closure member 240 is retracted from the valve flow channel 215 as far as possible to rest against the backseat 255 for allowing maximum conductance of the first fluid flow F1 through the valve flow channel 215. In certain embodiments, the closure member 240 is moved against the backseat 255 by the spring element 270. In certain embodiments, the closure member 240 is pulled against the backseat 255 by the spring element 270. In certain embodiments, the closure member 240 is pneumatically movable towards the backseat 255 to open the valve 200. The open configuration is preferred, for example, during a purge or after a processing step of a substrate processing apparatus 100 to maximize removal of excess processing fluid from a processing volume 115 of the substrate processing apparatus 100 which is connected to the first inlet 220.

[0091] In certain embodiments, the valve 200 is configured to provide a deliberate leak of second fluid flow F2, preferably a cleaning gas, from around the circumference of the closure member 240 to the valve flow channel 215 when the valve 200 is in a fully open configuration. That is, in certain embodiments, the sealing element 246 and backseat 255 are configured to provide a leak channel for the second fluid flow F2 when arranged against each other. In such embodiments, the second fluid flow F2 provided to the actuator is always configured to leak (or bleed) to the valve flow channel 215 regardless of the position of the closure member 240. Accordingly, an additional valve, such as pilot valve 170 is provided in certain embodiments to control the second fluid flow F2 to the actuator 260. Advantageously, cleaning gas may be provided to the valve internal parts always when the valve 200 is in use and the pilot valve 170 is in an open position.

[0092] When the valve 200 is in the open configuration, the deliberate leak of the second fluid flow 200 particularly flushes and protects the closure member 240 and backseat 255. Additionally, some of the second fluid flow F2 may protect the internal surface of the valve flow channel 215 and the valve seat 250.

[0093] Fig. 5 depicts the valve 200 according to certain embodiments in a partially open configuration. In such a situation, the valve flow channel is partially constricted by the closure element 240 to reduce first fluid flow F 1 through the valve 200. Such a configuration may be desired, when wishing to increase and control residence time of processing fluids in a processing volume 115 of a substrate processing apparatus 100. However, the reduced flow also increases the time which the valve internal parts are in contact with the processing fluids, thus, increasing the risk of contamination. By providing second fluid flow F2 of cleaning from the actuator 260 when the valve 200 is in a partially open configuration, contamination risk of the internal parts may be reduced. As a further advantage, the first fluid flow F1 from the substrate processing apparatus 100 and residence time of the processing fluid within the processing volume 115 may be simply and effectively controlled by the valve 200. Therefore, chamber design and upstream control means may be kept simple.

[0094] The second fluid flow F2 from the actuator 260 may effectively block or at least reduce access of the first fluid flow F1 towards the actuator chamber 265, stem 243, and the backseat 255 located beneath the sealing element 246, thus, cleaning said parts and protecting said parts from contamination when the valve 200 is in a partially open configuration. Furthermore, the sealing element 246 and its sealing surface which otherwise would be directly exposed to the first fluid flow F1 received through the first inlet 220 may be effectively flushed by the second fluid flow F2 provided from around the circumference of the sealing element 246, therefore, providing protection against deposition of the first fluid flow F1.

[0095] In addition, in certain embodiments, the sealing element 246 being arranged or moved close to the valve seat 250 is configured to provide second fluid flow F2 to the valve seat 250. For instance, immediately after opening the valve 200, the sealing member 240 and the valve seat 250 are very close to each other, wherein the second fluid flow F2 may be effectively provided to the valve seat 250 from around the circumference of the sealing member 240. Similar positional situation is also immediately before closing the valve 200. Advantageously, cleaning of the valve seat 250 may be enabled when moving the closure member 240. Further, reduction of undesired deposition of the first fluid flow F1 to the valve seat 250 may be achieved. In certain embodiments, the position of closure member 240 is controlled by a pneumatic actuator 260, wherein the pneumatic actuator is configured to be operated by the cleaning gas as a pneumatic gas. In certain embodiments, both opening and closing the valve 200 is pneumatically controlled. In certain embodiments, the pneumatic actuation is resisted by the spring element 270. Consequently, position of the closure member 240 is in certain embodiments, controlled by pneumatics in one direction and by a spring in other direction. That is the partially pneumatically controlled actuator may be spring-closable or springopenable depending on the embodiments.

[0096] In certain embodiments, the valve 200 is configured to use the second fluid flow F2 as pneumatic gas to operate the actuator 260. Therefore, in certain embodiments, the actuator 260 may be controlled by the pressure or flow rate of the second fluid flow F2. Advantageously, when having pneumatic actuator 260 and using the second fluid flow F2 cleaning gas as the pneumatic gas, cleaning the valve 200 may be effectively coupled with operating the valve 200.

[0097] Fig. 6 depicts the valve 200 according to certain embodiments in fully closed configuration. In the closed configuration, the sealing element 246 of the closure element 240 is arranged against the valve seat 250 to block the first fluid flow F1 through the valve 200. That is, the first fluid flow F1 is not allowed through the valve 200. Consequently, also flow through a foreline 150 coupled to the first inlet 220 may be blocked by simply closing the valve 200. No leak path through the valve seat 250 and the closure element 240 is provided. For example, the valve 200 may be arranged in the fully closed configuration during a substrate processing step of an ALD process, wherein the substrates 120 become exposed to the processing fluids and it is critical to retain the processing fluids within the processing volume 115.

[0098] In certain embodiments, the valve 200 is both closable and openable pneumatically.

[0099] In certain embodiments, the valve 200 is pneumatically openable. In certain embodiments, the valve 200 is closable by a spring element 270, such as a spring.

[0100] In certain embodiments, the valve 200 is pneumatically closable. In certain embodiments, the valve 200 is openable by a spring element 270, such as a spring.

[0101] When providing second fluid flow F2 of cleaning gas to the valve flow channel 215 from the actuator 260 when the valve 200 is in a closed configuration, stem 243 and non-sealing surfaces of the sealing element may be flushed with the cleaning gas. Also, internal surfaces of the valve flow channel 215 may at least partially be flushed, as well as parts of the foreline arranged downstream of the valve 200.

[0102] In certain alternative embodiments, the second fluid flow F2 is closed, for example, by the pilot valve 170, when the valve 200 is in a fully closed configuration. Advantageously, cleaning gas may be saved and only used when there is acute risk of contamination within the valve flow channel 215.

[0103] In general, the valves as described herein may provide effective reduction of undesired deposition of first fluid flow F1 onto internal parts of the valve 200. Further, cleaning of the internal parts may be effectively enabled. Still further, the internals of the actuator 260 and the valve 200 may simultaneously be cleaned and protected while operating the valve 200. Still further, gas usage may be simplified in certain embodiment where the cleaning gas of the second fluid flow F2 is used as pneumatic gas for a pneumatic actuator.

[0104] Fig. 7 depicts a method according to certain embodiments. The method comprises various steps. Certain steps may be omitted or repeated. Further steps may also be added or steps may be performed in a different order. Optional steps in Fig. 7 are marked within dashed boxes. For example, a substrate processing apparatus 100 according to embodiments depicted in Fig. 1 comprising a valve 200 according to embodiments depicted in Figs. 2-6 may be used to carry out the method. Structural features and operating principles of the substrate processing apparatus 100 and the valve 200 have been described already above.

[0105] Optional step 710 comprises providing the valve 200 in a foreline 150 of the substrate processing apparatus 100.

[0106] Optional step 720 comprises providing first fluid flow F1 from the substrate processing apparatus 100 to (a valve flow channel 215 of) the valve 200 through the foreline 150. In certain embodiments, the valve 200 comprises a pneumatic actuator 260. In certain embodiments, the actuator 260 is actuatable by pneumatics alone. In certain embodiments, the actuator 260 is actuatable by pneumatics and a spring element 270. In certain embodiments, the method comprises receiving processing fluids, as the first fluid flow F1 , from the processing volume 115 of the substrate processing apparatus 100 to the valve flow channel 215 of the valve 200. Step 730 comprises receiving first fluid flow F1 into (the valve flow channel 215 of) the valve 200. In certain embodiments, the first fluid flow F1 is received from the foreline 150 of the substrate processing apparatus 100.

[0107] Step 740 comprises adjusting the valve 200 by the actuator 260 (of the valve 200) to control the first fluid flow F1 through (the valve flow channel 215 of) the valve (and the foreline 150). In certain embodiments, the method comprises controlling the first fluid flow F1 through the valve 200 by adjusting the position of the closure member 240 within a valve flow channel 215 by the actuator 260. In certain embodiments, the method comprises providing a spring element 270 to operate against the pneumatic actuator 260 to further adjust the valve 200. Advantageously, simple and robust valve control may be enabled.

[0108] Step 750 comprises providing a deliberate leak of cleaning gas, a second fluid flow F2, into (the valve flow channel 215 of) the valve 200 from the actuator 260 for cleaning internal parts of the valve 200. In certain embodiments, the method comprises receiving cleaning gas from the cleaning gas source 160 through the actuator 260 to the valve flow channel 215. In certain embodiments, the method comprises providing the leak path for the second fluid flow F2 (from the second inlet 280) through the actuator 260 into the valve flow channel 215. In certain embodiments, the method comprises cleaning the internal parts of the valve 200 with the cleaning gas. In certain embodiments, the method comprises cleaning the internal parts of the valve 200 with the cleaning gas while operating the valve 200. In certain embodiments, the method comprises cleaning the valve seat 250. In certain embodiments, the method comprises cleaning the closure member 240. In certain embodiments, the method comprises cleaning the backseat 255. In certain embodiments, the method comprises cleaning the (inside of) actuator chamber 265. In certain embodiments, the method comprises cleaning the valve flow channel 215 walls.

[0109] Step 760 comprises providing the second fluid flow F2, to the valve 200 from the actuator 260 (simultaneously) when adjusting the valve 200. In certain embodiments, method comprises providing the second fluid flow F2 into (the valve flow channel 215 of) the valve 200 simultaneously with the first fluid flow F1.

[0110] Step 770 comprises the valve 200 comprising a pneumatic actuator, wherein the method comprises using the second fluid flow F2 (cleaning gas) as pneumatic gas (for operating the actuator 260). Advantageously, gas usage may be simplified as the same gas may be used for both cleaning and operating the valve. Furthermore, cleaning and use of the valve may be effectively coupled and synchronized.

[0111] Step 780 comprises controlling the second fluid flow to the actuator 260 by a pilot valve 270.

[0112] Without limiting the scope and / or interpretation of the claims, certain technical effects and / or advantages of one or more of the example embodiments disclosed herein are listed in the following. An advantage is reduction of undesired processing fluid deposition onto internal parts of the valve. A further advantage is cleaning of the internal parts of the valve while using the valve. A still further advantage is longer lifetime of the valve. A still advantage is reduced need for maintenance. A still further advantage, simplified gas usage as the cleaning gas may be used both for cleaning and as pneumatic gas to operate the pneumatic actuator. A still further advantage is a valve with improved reliability in harsh and hot conditions. Still further advantage is that the substrate processing apparatus and upstream flow control means may be kept simple as the valve enables simple control of processing fluid residence time upstream of the valve.

[0113] Various embodiments have been presented. It should be appreciated that in this document, words comprise, include, and contain are each used as open-ended expressions with no intended exclusivity.

[0114] The foregoing description has provided by way of non-limiting examples of particular implementations and embodiments a full and informative description of the best mode presently contemplated by the inventors for carrying out the invention. It is however clear to a person skilled in the art that the invention is not restricted to details of the embodiments presented in the foregoing, but that it can be implemented in other embodiments using equivalent means or in different combinations of embodiments without deviating from the characteristics of the invention.

[0115] Furthermore, some of the features of the afore-disclosed example embodiments may be used to advantage without the corresponding use of other features. As such, the foregoing description shall be considered as merely illustrative of the principles of the present invention, and not in limitation thereof. Hence, the scope of the invention is only restricted by the appended patent claims.

Claims

CLAIMS1. A substrate processing apparatus (100) comprising: a reaction chamber (110) for processing at least one substrate (120); a foreline (150) for removing processing fluid from the reaction chamber (110); a valve (200), comprising an actuator (260) to adjust the valve (200), arranged in the foreline (150) for controlling flow of the processing fluid, first fluid flow (F1), through the valve (200), wherein the valve (200) is configured to provide a deliberate leak of cleaning gas, second fluid flow (F2), from the actuator (260) into the valve (200).

2. The substrate processing apparatus (100) of claim 1 , wherein the cleaning gas is inert gas or a mixture of two or more inert gases.

3. The substrate processing apparatus (100) of claim 1 or 2, wherein the actuator (260) is configured to provide the second fluid flow (F2) into the valve (200) when adjusting the valve (200).

4. The substrate processing apparatus (100) of any preceding claim, wherein the actuator (260) is a pneumatic actuator.

5. The substrate processing apparatus (100) of any one of claims 1-3, wherein the actuator (260) is actuatable by pneumatics and a spring element (270).

6. The substrate processing apparatus (100) of claim 4 or 5, wherein the actuator (260) is configured to use the cleaning gas (F2) as a pneumatic gas.

7. The substrate processing apparatus (100) of any preceding claim, wherein the valve (200) comprises a leak path for providing the deliberate leak of the second fluid flow (F2) through the actuator (260) into the valve (100).

8. The substrate processing apparatus (100) of claim 7, wherein the valve (200) comprises a closure member (240) which is movable by the actuator (260) and arranged at least partially within the actuator (260), wherein the leak path is defined at least partially by the movable closure member (240).

9. The substrate processing apparatus (100) of claim 8, wherein the closure member (240) comprises perforations (241), the perforations being configured to form a part of the leak path.

10. The substrate processing apparatus (100) of any preceding claim, wherein the valve (200) is manufactured of metal or metal alloys.11 . The substrate processing apparatus (100) of any preceding claim, comprising a pilot valve (170) configured to control the second fluid flow (F2) to the actuator (260).

12. A valve (200), comprising: an actuator (260) for adjusting the valve (200) to control first fluid flow (F1) through the valve (200); wherein the valve (200) is configured to provide a deliberate leak of cleaning gas, second fluid flow (F2), from the actuator (260) into the valve (200).

13. A method for operating a valve (200), comprising. receiving a first fluid flow (F1) into the valve (200); adjusting the valve (200) by an actuator (260) to control the first fluid flow (F1) through the valve (200); and providing a deliberate leak of cleaning gas, a second fluid flow (F2), from the actuator (260) into the valve (200).

14. The method of claim 13 further comprising: providing the valve (200) in a foreline (150) of a substrate processing apparatus (100); and providing the first fluid flow (F1) from the substrate processing apparatus (100) to the valve (200) through the foreline (150).

15. The method of claim 13 or 14, wherein the actuator (260) is a pneumatic actuator, the method further comprising: using the second fluid flow (F2) as pneumatic gas.

16. The method of any one of the claims claim 13-15, further comprising: providing the second fluid flow (F2) into the valve (200) from the actuator (260) when adjusting the valve (200).

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