Automated cleaning of load locks in substrate handling systems

Abstract

A method for cleaning a load lock in a substrate processing system comprises: during a first period, opening a first valve in fluid communication with a gas source to supply gas through a first vent into a gas volume of the load lock. The gas is supplied at a pressure and flow rate sufficient to disturb particles from surfaces of the load lock. The method comprises: during a second period following the first period, while the first valve is open, opening a second valve in fluid communication with a pump and activating the pump to flush the gas and particles from the gas volume of the load lock; and during a third period following the second period, closing the first valve while continuing to pump the gas and particles from the gas volume of the load lock through the second valve.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 62 / 912,584, filed on October 8, 2019. The entire disclosure of the above-referenced application is incorporated herein by reference. Technical Field

[0003] The present disclosure relates to cleaning components in substrate processing systems. Background Art

[0004] The background description provided here is for the purpose of generally presenting the context of the present disclosure. No admission is made, either explicitly or implicitly, that the work of the presently designated inventors is prior art to the present disclosure to the extent that it is described in this background section and in aspects of the specification that were not determined to be prior art at the time the application was filed.

[0005] The substrate processing system can be used to process substrates such as semiconductor wafers. Exemplary processes that can be performed on the substrate include, but are not limited to, chemical vapor deposition (CVD), atomic layer deposition (ALD), conductor etching, rapid thermal processing (RTP), ion implantation, physical vapor deposition (PVD), and / or other etching, deposition, or cleaning processes. The substrate can be arranged on a substrate support, such as a susceptor, an electrostatic chuck (ESC), etc., in a processing chamber of the substrate processing system. During processing, a gas mixture including one or more precursors can be introduced into the processing chamber, and a plasma can be used to induce a chemical reaction. Summary of the Invention

[0006] A method for cleaning a load lock in a substrate processing system comprises: during a first period, opening a first valve in fluid communication with a gas source to supply gas through a first vent into a gas volume of the load lock. The gas is supplied at a pressure and flow rate sufficient to disturb particles from surfaces of the load lock. The method comprises: during a second period following the first period, while the first valve is open, opening a second valve in fluid communication with a pump and activating the pump to flush the gas and particles from the gas volume of the load lock; and during a third period following the second period, closing the first valve while continuing to pump the gas and particles from the gas volume of the load lock through the second valve.

[0007] In other features, the first vent corresponds to an annular vent surrounding the periphery of the load lock. The first vent corresponds to a bottom vent extending through a bottom portion of the load lock. The first vent corresponds to a top vent extending through a lid portion of the load lock. The gas is supplied through the first vent at a flow rate of at least 170 standard liters per minute. The first time period is 0-10 seconds. The first time period is less than 1 second. The second time period is 1-60 seconds. The second time period is less than 10 seconds. The third time period is 0.5-1.5 seconds. The method further includes repeatedly opening the first valve, opening the second valve, turning on the pump, and closing the first valve.

[0008] In other features, the method further includes opening a third valve in fluid communication with the gas source during the first period to supply the gas through a third vent into the gas volume of the load lock. The method further includes alternating opening of the first and third valves during the first period. The method further includes opening the third valve in fluid communication with the gas source during a fourth period to supply the gas through a third vent into the gas volume of the load lock; opening the second valve and activating the pump to flush the gas and the particles from the gas volume of the load lock during a fifth period following the fourth period while the third valve is open; and closing the third valve during a sixth period following the fifth period while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve.

[0009] A system for cleaning a load lock in a substrate processing system includes a first valve in fluid communication with a gas source and a gas volume of the load lock; a second valve in fluid communication with a pump and the gas volume; and a controller configured to, during a first period, open the first valve to supply gas through a first vent into the gas volume of the load lock. The gas is supplied at a pressure and flow rate sufficient to disturb particles from a surface of the load lock. The controller is further configured to, during a second period following the first period and while the first valve is open, open the second valve and activate the pump to flush the gas and particles from the gas volume of the load lock; and, during a third period following the second period, close the first valve while continuing to pump the gas and particles from the gas volume of the load lock through the second valve.

[0010] In other features, the first vent corresponds to an annular vent surrounding the periphery of the load lock. The first vent corresponds to a bottom vent extending through a bottom portion of the load lock. The first vent corresponds to a top vent extending through a lid portion of the load lock. The controller is configured to control the supply of gas through the first vent at a flow rate of at least 170 standard liters per minute. The first time period is 0-10 seconds. The first time period is less than 1 second. The second time period is 1-60 seconds. The second time period is less than 10 seconds. The third time period is 0.5-1.5 seconds. The controller is configured to repeatedly open the first valve, open the second valve and turn on the pump, and close the first valve.

[0011] In other features, during the first time period, the controller is configured to open a third valve in fluid communication with the gas source to supply the gas through a third vent into the gas volume of the load lock. The controller is configured to alternately open the first and third valves during the first time period. The controller is further configured to: during a fourth time period, open the third valve in fluid communication with the gas source to supply the gas through the third vent into the gas volume of the load lock; during a fifth time period following the fourth time period and with the third valve open, open the second valve and activate the pump to flush the gas and the particles from the gas volume of the load lock; and during a sixth time period following the fifth time period, close the third valve while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve.

[0012] Further scope of applicability of the present disclosure will become apparent from the detailed description, claims and drawings.The detailed description and specific examples are intended for purposes of illustration only and are not intended to limit the scope of the disclosure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The present disclosure will be more fully understood from the detailed description and accompanying drawings, in which:

[0014] Figure 1 is an exemplary substrate processing system according to the principles of the present disclosure;

[0015] Figure 2 is an exemplary automated cleaning system according to the principles of the present disclosure;

[0016] Figure 3 An exemplary method for automated cleaning of a load lock according to the principles of the present disclosure is provided; and

[0017] Figure 4A 、 4B4C are exemplary load lock configurations according to the principles of the present disclosure.

[0018] Among the drawings, reference numerals may be repeated to identify similar and / or identical elements. DETAILED DESCRIPTION

[0019] In a substrate processing system, substrates may be transferred to and from processing chambers via various modules or chambers defining respective volumes, including, but not limited to, a front-end module, a load lock, and / or a vacuum transfer module. As substrates are transferred throughout the substrate processing system, particles may accumulate within the various chambers over time. For example, particles may form through mechanical contact between chamber components or between chamber components and input and / or processing substrates.

[0020] Typically, the chamber and its corresponding components are precision cleaned prior to assembly (e.g., using various treatments including acids, bases, sonication, detergents, etc.). After assembly, precision cleaning is more difficult and may not be feasible for most substrate processing systems. For example, only certain components can be removed relatively easily for precision cleaning. Precision cleaning operations for other components (including the walls of the chamber) may require disassembly, transfer to a cleaning facility, and then reinstallation. Therefore, post-assembly precision cleaning operations are time-consuming and increase operating costs.

[0021] In some examples, various cleaning processes can be performed. For example, after a predetermined amount of particle accumulation (e.g., when the particle count measured on the substrate exceeds a predetermined threshold), production can be interrupted and the chamber opened for a wet cleaning process. For example, the interior of the chamber can be wet cleaned using cleanroom wipes. However, interrupting production for wet cleaning reduces production capacity. Additionally, wet cleaning may not effectively remove all accumulated particles.

[0022] In other examples, a pump-and-drain cleaning process can be performed. In a pump-and-drain cycle, gas is pumped into the chamber and then exhausted. However, cleaning efficiency using multiple pump-and-drain cycles is very low. For example, thousands of pump-and-drain cycles (e.g., more than 9,000) may be required to clean a chamber such as a load lock.

[0023] The automatic cleaning system and method according to the present disclosure are configured to impact the accumulated particles in the chamber into the gas volume for effective removal. Conventional discharge of chambers such as load locks minimizes flow and fluid velocity to prevent disturbance of the accumulated particles. Therefore, the particles are not impacted (i.e., are made to float in the air in the volume), and the removal of the particles is limited. On the contrary, the automatic cleaning system and method according to the present disclosure provide increased flow and velocity in the chamber in one or more alternating impact, flushing, and pumping cycles to increase the particle removal rate.

[0024] Although described with respect to a load lock, the principles of the present disclosure may also be implemented within other chambers of a substrate processing system, including but not limited to vacuum transfer modules (VTMs), process modules, and the like.

[0025] Now refer to Figure 1 , an exemplary substrate processing system 100 is shown. By way of example only, the substrate processing system 100 can be used to perform deposition and / or etching using RF plasma and / or to perform other suitable substrate processing. The substrate processing system 100 includes a processing chamber 102, which surrounds the other components of the substrate processing system 100 and contains the RF plasma. The processing chamber 102 includes an upper electrode 104 and a substrate support 106, such as an electrostatic chuck (ESC). During operation, a substrate 108 is disposed on the substrate support 106. Although a particular substrate processing system 100 and processing chamber 102 are shown as an example, the principles of the present disclosure can be applied to other types of substrate processing systems and chambers, such as substrate processing systems that generate plasma in situ, substrate processing systems that implement remote plasma generation and delivery (e.g., using a plasma tube, microwave tube), and the like.

[0026] By way of example only, the upper electrode 104 may include a gas distribution device, such as a showerhead 109, that introduces and distributes the process gas. The showerhead 109 may include a stem portion including one end connected to the top surface of the process chamber 102. A base portion is generally cylindrical and extends radially outward from an opposite end of the stem portion at a position spaced from the top surface of the process chamber 102. A substrate-facing surface or faceplate of the base portion of the showerhead 109 includes a plurality of holes through which the process gas or purge gas flows. Alternatively, the upper electrode 104 may include a conductive plate, and the process gas may be introduced in another manner.

[0027] The substrate support 106 includes a conductive substrate 110 that serves as a lower electrode. The substrate 110 supports a ceramic layer 112. In some examples, the ceramic layer 112 can include a heating layer, such as a ceramic multi-zone heating plate. A thermal resistance layer 114 (e.g., a bonding layer) can be disposed between the ceramic layer 112 and the substrate 110. The substrate 110 can include one or more coolant channels 116 for flowing a coolant through the substrate 110. The substrate support 106 can include an edge ring 118 disposed around the outer perimeter of the substrate 108.

[0028] The RF generation system 120 generates an RF voltage and outputs the RF voltage to one of the upper electrode 104 and the lower electrode (e.g., the substrate 110 of the substrate support 106). The other of the upper electrode 104 and the substrate 110 can be DC grounded, AC grounded, or floating. By way of example only, the RF generation system 120 can include an RF voltage generator 122 that generates an RF voltage that is fed to the upper electrode 104 or the substrate 110 by a matching and distribution network 124. In other examples, the plasma can be generated inductively or remotely. Although, as shown for illustrative purposes, the RF generation system 120 corresponds to a capacitively coupled plasma (CCP) system, the principles of the present disclosure can also be implemented in other suitable systems, such as, by way of example only, a transformer coupled plasma (TCP) system, a CCP cathode system, a remote microwave plasma generation and delivery system, and the like.

[0029] The gas delivery system 130 includes one or more gas sources 132-1, 132-2, ..., and 132-N (collectively, gas sources 132), where N is an integer greater than zero. The gas sources provide one or more gas mixtures. The gas sources may also supply a purge gas. Vaporized precursors may also be used. The gas sources 132 are connected to a manifold 140 via valves 134-1, 134-2, ..., and 134-N (collectively, valves 134) and mass flow controllers 136-1, 136-2, ..., and 136-N (collectively, mass flow controllers 136). The output of the manifold 140 is supplied to the processing chamber 102. By way of example only, the output of the manifold 140 is supplied to the showerhead 109.

[0030] The temperature controller 142 can be connected to a plurality of heating elements, such as thermal control elements (TCEs) 144 disposed in the ceramic layer 112. For example, the heating elements 144 can include, but are not limited to, large heating elements corresponding to individual zones in a multi-zone heating plate and / or an array of micro-heating elements disposed across multiple zones of the multi-zone heating plate. The temperature controller 142 can be used to control the plurality of heating elements 144 to control the temperature of the substrate support 106 and the substrate 108.

[0031] The temperature controller 142 can communicate with the coolant assembly 146 to control the flow of coolant through the channel 116. For example, the coolant assembly 146 can include a coolant pump and a reservoir. The temperature controller 142 operates the coolant assembly 146 to selectively flow coolant through the channel 116 to cool the substrate support 106.

[0032] A valve 150 and a pump 152 may be used to evacuate reactants from the process chamber 102. A system controller 160 may be used to control the components of the substrate processing system 100. One or more robots 170 may be used to transport substrates onto and remove substrates from the substrate support 106. For example, the robot 170 may transfer substrates between the EFEM 171 and the load lock 172, between the load lock and the VTM 173, between the VTM 173 and the substrate support 106, and so on. Although the temperature controller 142 is shown as a separate controller, the temperature controller 142 may be implemented within the system controller 160. In some examples, a protective seal 176 may be provided around the outer periphery of the bonding layer 114, between the ceramic layer 112 and the substrate 110.

[0033] According to principles of the present disclosure, substrate processing system 100 is configured for automated cleaning systems and methods to remove particles from load lock 172 (and / or other chambers such as EFEM 171 , VTM 173 , etc.) For example, system controller 160 may be configured to control a gas delivery system.

[0034] Reference Figure 2 , an exemplary automated cleaning system 200 is described in greater detail, which is configured to perform an automated cleaning (e.g., pumping / draining) process on a load lock 204. During the automated cleaning process, the load lock 204 remains closed (i.e., not open to the atmosphere). In other words, the automated cleaning process is performed in situ.

[0035] The automated cleaning system 200 includes a gas delivery system 208, which may correspond to Figure 1 The illustrated gas delivery system 130 may correspond to a separate gas delivery system. The gas delivery system 208 includes at least one gas source 212 and a valve 216. The gas source 212 stores a cleaning or sweeping gas (e.g., molecular nitrogen, or N2), a mixture of gases, or the like. The gas source 212 may be pressurized (i.e., stored in a liquid form under pressure). A controller 220 (e.g., corresponding to the system controller 160) selectively opens and closes the valve 216 to allow the pressurized gas to flow into the load lock 204. The gas flowing into the load lock 204 displaces particles accumulated on the interior surfaces of the load lock 204 into the gas volume 224. Conversely, the controller 220 is configured to control the valve 228 and pump 232 to flush (i.e., evacuate) the gas and airborne particles from the load lock 204 and evacuate the load lock 204 to a vacuum pressure. The controller 220 may be responsive to inputs, including, but not limited to, user inputs and signals received from corresponding sensors 236.

[0036] Although shown with a single valve 216 and corresponding vent location 240 , in some examples, the load lock 204 may include multiple vent locations and corresponding valves. For example, the vent locations may include, but are not limited to, side surfaces, top surfaces, and bottom surfaces of the load lock 204 .

[0037] Reference Figure 3 And continue to refer to Figure 2 , an exemplary method 300 for performing an automatic cleaning process on a load lock according to the present disclosure begins at 304. At 308, the method 300 determines whether to perform an automatic cleaning process. For example, the controller 220 may initiate the automatic cleaning process periodically, conditionally, or the like in response to one or more signals (e.g., from corresponding sensors 236) indicating a specific amount of accumulation within the load lock 204. By way of example only, one or more of the sensors 236 may be configured to function as a particle counter that detects particle accumulation on the sensors. The controller 220 may be configured to trigger the automatic cleaning process for a predetermined period of time in response to a predetermined number of substrates being processed and / or transferred within the load lock 204, etc., after a previous automatic cleaning process has been performed. In some examples, the controller 220 may perform the automatic cleaning process in response to user input.

[0038] If the answer to 308 is yes, the method 300 proceeds to 312. If not, the method 300 returns to 308. At 312, the method 300 impacts the particles within the load lock 204 into the gas volume 224 in an impact step or period. For example, the controller 220 opens the valve 216 to provide pressurized gas from the gas source 212 to the load lock 204 at a flow rate sufficient to disturb the particles from the surface of the load lock 204 and cause them to become airborne. The valve 228 remains closed during the impact period.

[0039] By way of example only, N2 or another gas (or gas mixture) is provided at approximately 70 psi (e.g., 65-75 psi) to achieve a flow rate of at least 170 standard liters per minute (SLM). In some examples, the flow rate of the gas is between 180 and 250 SLM. The surge period may be between 0 and 10 seconds. In some examples, the surge period is less than 1 second (e.g., 0.5 seconds). Prior to the surge period, the pressure within load lock 204 may be at vacuum pressure (e.g., less than 1 Torr). The pressure within load lock 204 may be increased during the surge period (e.g., to 700-800 Torr).

[0040] After the impact period, method 300 flushes the disturbed, impacted particles from load lock 204 in a flush step or period at 316. For example, valve 216 remains open, and controller 220 opens valve 228 and starts pump 232. By way of example only, pump 232 operates at a pump rate of at least 1700 SLM. With valves 216 and 228 open, pressurized gas continues to flow into the load lock through valve 216 to flush both the particles and gas from load lock 204 via valve 228. The flow rate of gas and particles during the flush period can be at least 170 SLM (e.g., 180-250 SLM). The flush period can be between 1 and 60 seconds. In some examples, the flush period is between 1 and 10 seconds. The pressure within load lock 204 can be reduced from 700-800 Torr to less than 1 Torr during the flush period.

[0041] In some examples, during the flushing period, the pump rate can be controlled to maintain a desired pressure within the load lock 204. For example, the flushing efficiency may vary with pressure for different load locks or other chambers. Therefore, during the flushing period, the pump rate can be controlled to maintain the pressure within a desired range (e.g., 10-100 Torr). By way of example only, the sensor 236 may include a pressure sensor configured to provide a signal indicative of the pressure within the load lock 204. The sensor 236 may also include corresponding sensors configured to measure other parameters within the load lock 204, including, but not limited to, flow rates / velocities at various locations within the load lock 204. In this way, the pressure, pump rate, etc. can be controlled to achieve the desired flow rate for various time periods.

[0042] After the flushing period, method 300 removes the remaining impacted particles from load lock 204 during a pumping step or period at 320 and evacuates load lock 204 to a desired vacuum pressure. For example, valve 228 remains open, and controller 220 closes valve 216. With valve 228 open, the pump activated (e.g., above 1700 SLM), and valve 216 closed, the remaining gas and disturbed particles are pumped out of load lock 204. The pumping period can be approximately 1 second (e.g., between 0.5 and 1.5 seconds). During the pumping period, the pressure within load lock 204 can be maintained below 1 Torr. In some examples, the pumping period can continue until the desired pressure (e.g., below 40 mTorr) is reached.

[0043] After the pumping period, method 300 determines at 324 whether to perform an additional automatic cleaning cycle. For example, an automatic cleaning cycle may include a surge period, a rinse period, and a pumping period, and the automatic cleaning process may include two or more automatic cleaning (surge / rinse / pumping) cycles. In some examples, a predetermined number of automatic cleaning cycles are performed (e.g., 2-1000 cycles). In other examples, the automatic cleaning cycle may be repeated until the sensed particle level (e.g., via sensor 236) is below a predetermined threshold. If the result of 324 is yes, method 300 proceeds to 312. If not, method 300 ends at 328.

[0044] While the control of valve 216 and vent position 240 is described, in some examples, multiple valves may be individually controlled to provide gas to load lock 204 via corresponding vent positions. For example, an auto-clean process may include: opening a first valve corresponding to a first vent position during the surge and rinse period of a first auto-clean cycle; opening a second valve corresponding to a second vent position during the surge and rinse period of a second auto-clean cycle; opening a third valve corresponding to a third vent position during the surge and rinse period of a third auto-clean cycle, and so on. In some examples, each vent may be opened for a predetermined number of auto-clean cycles. The same vent may be opened in consecutive auto-clean cycles, or the vents opened in consecutive auto-clean cycles may be different (i.e., the opened vents may alternate).

[0045] Now refer to Figure 4A 、 4B 4C, shows an exemplary configuration of a load lock 400 according to the present disclosure. The load lock 400 includes a first chamber 404 and a second chamber 408, which are configured to accommodate respective substrates. The chambers 404 and 408 define respective gas volumes 412 and 416. Figure 4A As shown, load lock 400 includes an annular vent 420. For example, annular vent 420 surrounds the periphery of the upper region of load lock 400. During the impingement period, gas is supplied into chambers 404 and 408 via annular vent 420 to impinge particles within gas volumes 412 and 416, as described above. For example, gas is supplied inwardly via annular vent 420 and directed downwardly along inner walls 424 of chambers 404 and 408. The gas and particles generally follow a path as indicated by the dashed arrows. Thus, the gas disturbs particles accumulated on inner walls 424 and impinges the particles into gas volumes 412 and 416. The gas and particles are flushed and / or pumped out of chambers 404 and 408 via corresponding pumping vents 428 and 432.

[0046] like Figure 4BAs shown, load lock 400 includes top vents 436 and 440 that are configured to supply gas to respective chambers 404 and 408 (e.g., through a cover 444 of load lock 400). During the impingement period, gas is supplied into chambers 404 and 408 via top vents 436 and 440 to impinge particles within gas volumes 412 and 416, as described above. For example, gas is supplied downwardly via top vents 436 and 440 and directed radially outwardly along bottom surface 448 before being directed upwardly along inner wall 424 of chambers 404 and 408. The gas and particles generally follow a path as indicated by the dashed arrows.

[0047] like Figure 4C As shown, load lock 400 includes bottom vents 452 and 456 that are configured (e.g., via lid 444 of load lock 400) to supply gas to respective chambers 404 and 408. During the impingement period, gas is supplied into chambers 404 and 408 via bottom vents 452 and 456 to impinge particles within gas volumes 412 and 416, as described above. For example, gas is supplied upwardly via bottom vents 452 and 456 and directed radially outwardly along top surface 460 before being directed downwardly along inner wall 424 of chambers 404 and 408. The gas and particles generally follow a path as indicated by the dashed arrows.

[0048] Although Figure 4A 、 4B 4C are shown with a single configuration of load lock 400, but in other examples, load lock 400 may include vents in two or more locations. For example, load lock 400 may include two or more of annular vent 420, top vents 436 and 440, and bottom vents 452 and 456. Thus, by supplying gas through the corresponding vents, particles can be disturbed and impacted from each of the inner wall 424, bottom surface 448, and top surface 460 of chambers 404 and 408. For example, the corresponding valves corresponding to annular vent 420, top vents 436 and 440, and bottom vents 452 and 456 can be opened sequentially during the same impact period, opened during different impact periods in their respective automatic cleaning cycles, and so on.

[0049] The foregoing description is merely illustrative in nature and is in no way intended to limit the present disclosure, its application or use. The broad teachings of the present disclosure can be implemented in various forms. Therefore, although the present disclosure includes specific examples, the true scope of the present disclosure should not be so limited, because other modifications will become apparent when studying the drawings, description and appended claims. It should be understood that one or more steps in the method can be performed in a different order (or simultaneously) without changing the principles of the present disclosure. In addition, although each embodiment is described above as having certain features, any one or more of those features described with respect to any embodiment of the present disclosure can be implemented in the features of any other embodiment and / or combined with the features of any other embodiment, even if the combination is not explicitly described. In other words, the embodiments described are not mutually exclusive, and the permutation of one or more embodiments with each other remains within the scope of the present disclosure.

[0050] Various terms are used to describe the spatial and functional relationships between elements (e.g., between modules, between circuit elements, between semiconductor layers, etc.), including "connected," "engaged," "coupled," "adjacent," "next to," "on top of," "above," "below," and "disposed." Unless the relationship between a first and a second element is explicitly described as "direct," when such a relationship is described in the above disclosure, the relationship can be a direct relationship, in which there are no other intervening elements between the first and second elements, but can also be an indirect relationship, in which there are one or more intervening elements (spatially or functionally) between the first and second elements. As used herein, the phrase "at least one of A, B, and C" should be construed to mean a logical (A or B or C), using a non-exclusive logical OR, and should not be construed to mean "at least one of A, at least one of B, and at least one of C."

[0051] In some implementations, the controller is part of a system, which can be part of the examples above. Such a system can include semiconductor processing equipment, which includes one or more processing tools, one or more chambers, one or more platforms for processing, and / or specific processing components (wafer pedestals, gas flow systems, etc.). These systems can be integrated with electronic devices for controlling their operation before, during, and after processing of semiconductor wafers or substrates. The electronic device can be referred to as a "controller" and can control various components or subcomponents of one or more systems. Depending on the processing requirements and / or system type, the controller can be programmed to control any of the processes disclosed herein, including the delivery of process gases, temperature settings (e.g., heating and / or cooling), pressure settings, vacuum settings, power settings, radio frequency (RF) generator settings, RF matching circuit settings, frequency settings, flow rate settings, fluid delivery settings, position and operation settings, wafer transfer into and out of tools connected to or interfaced with a specific system and other transfer tools and / or load locks.

[0052] In general, a controller can be defined as an electronic device having various integrated circuits, logic, memory, and / or software that receive instructions, issue instructions, control operations, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits can include chips in the form of firmware that stores program instructions, digital signal processors (DSPs), chips defined as application specific integrated circuits (ASICs), and / or one or more microprocessors or microcontrollers that execute program instructions (e.g., software). The program instructions can be instructions sent to the controller in the form of various separate settings (or program files) that define operating parameters for performing specific processes on or for a semiconductor wafer or system. In some embodiments, the operating parameters can be part of a recipe defined by a process engineer to complete one or more process steps during the manufacture of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and / or the die of the wafer.

[0053] In some implementations, the controller can be part of or coupled to a computer that is integrated with the system, coupled to the system, otherwise networked to the system, or a combination thereof. For example, the controller can be in the "cloud" or all or part of a wafer fab host system that can allow remote access to wafer processing. The computer can enable remote access to the system to monitor the current progress of manufacturing operations, review the history of past manufacturing operations, review trends or performance metrics for multiple manufacturing operations, change parameters of the current process, set processing steps to follow the current process, or start a new process. In some examples, a remote computer (e.g., a server) can provide process recipes to the system via a network (which can include a local network or the Internet). The remote computer can include a user interface that enables the input or programming of parameters and / or settings, which are then sent from the remote computer to the system. In some examples, the controller receives instructions in the form of data that specify parameters for each processing step to be performed during one or more operations. It should be understood that the parameters can be specific to the type of process to be performed and the type of tool the controller is configured to interface with or control. Thus, as described above, the controller can be distributed, for example, by including one or more discrete controllers networked together and working toward a common purpose (e.g., processing and control as described herein). An example of a distributed controller for such a purpose is one or more integrated circuits on a chamber communicating with one or more integrated circuits remotely (e.g., at a platform level or as part of a remote computer), which combine to control processing on the chamber.

[0054] Example systems may include, but are not limited to, plasma etch chambers or modules, deposition chambers or modules, spin rinse chambers or modules, metal plating chambers or modules, cleaning chambers or modules, bevel edge etch chambers or modules, physical vapor deposition (PVD) chambers or modules, chemical vapor deposition (CVD) chambers or modules, atomic layer deposition (ALD) chambers or modules, atomic layer etch (ALE) chambers or modules, ion implantation chambers or modules, track chambers or modules, and any other semiconductor processing system that may be associated with or used in the manufacture and / or preparation of semiconductor wafers.

[0055] As described above, depending on one or more processing steps to be performed by the tool, the controller may communicate with one or more other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout the fab, a host computer, another controller, or tools used in the material transport of wafer containers to and from tool locations and / or load ports in a semiconductor fabrication facility.

Claims

1. A method for cleaning a load lock in a substrate processing system, the method comprising: (a) during a first period, opening a first valve in fluid communication with a gas source to supply gas downwardly through a top vent into a gas volume of the load lock, wherein the top vent is in a top surface of the load lock and the gas is supplied at a pressure and flow rate sufficient to disturb particles from at least a bottom surface of the load lock; (b) during a second period after the first period and with the first valve open, (i) opening a second valve in fluid communication with a pump, and (ii) activating the pump to flush the gas and the particles from the gas volume of the load lock; (c) during a third period following the second period, closing the first valve while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve; (d) during a fourth period, opening a third valve in fluid communication with the gas source to supply the gas upwardly through a bottom vent in the bottom surface of the load lock and into the gas volume of the load lock at a pressure and flow rate sufficient to disturb particles from at least the top surface of the load lock; (e) in a fifth period after the fourth period and with the third valve open, (i) opening the second valve, and (ii) starting the pump to flush the gas and the particles from the gas volume of the load lock; as well as (f) during a sixth period following the fifth period, closing the third valve while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve. 2 . The method of claim 1 , wherein supplying gas comprises supplying gas through an annular vent around a periphery of the load lock. 3 . The method of claim 1 , wherein the top vent extends through a cover of the load lock.

4. The method of claim 1 wherein the gas is supplied through the top vent at a flow rate of at least 170 standard liters per minute. The method according to claim 1 , wherein the first period of time is 0-10 seconds. The method of claim 1 , wherein the first period of time is less than 1 second. The method according to claim 1 , wherein the second period of time is 1-60 seconds. The method of claim 1 , wherein the second period of time is less than 10 seconds. The method according to claim 1 , wherein the third period of time is 0.5-1.5 seconds.

10. The method of claim 1, further comprising repeating steps (a), (b), and (c).

11. The method of claim 1 , further comprising opening a fourth valve in fluid communication with the gas source during the first period to supply the gas through a third vent into the gas volume of the load lock. 12 . The method of claim 11 , further comprising alternately opening the first valve and the fourth valve during the first period.

13. A system for cleaning a load lock in a substrate processing system, comprising: a first valve in fluid communication with a gas source and a gas volume of the load lock; a second valve in fluid communication with the pump and the gas volume; and A controller configured to: (a) during a first period, opening the first valve to supply gas downwardly through a top vent into a gas volume of the load lock, wherein the top vent is in a top surface of the load lock and the gas is supplied at a pressure and flow rate sufficient to disturb particles from at least a bottom surface of the load lock; (b) during a second period after the first period and with the first valve open, (i) opening the second valve, and (ii) activating the pump to flush the gas and the particles from the gas volume of the load lock; (c) during a third period following the second period, closing the first valve while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve; (d) during a fourth period, opening a third valve in fluid communication with the gas source to supply the gas upwardly through a bottom vent in the bottom surface of the load lock and into the gas volume of the load lock at a pressure and flow rate sufficient to disturb particles from at least the top surface of the load lock; (e) in a fifth period after the fourth period and with the third valve open, (i) opening the second valve, and (ii) starting the pump to flush the gas and the particles from the gas volume of the load lock; as well as (f) during a sixth period following the fifth period, closing the third valve while continuing to pump the gas and the particles from the gas volume of the load lock through the second valve.

14. The system of claim 13, wherein supplying gas comprises supplying gas through an annular vent around a periphery of the load lock.

15. The system of claim 13, wherein the top vent extends through a cover of the load lock.

16. The system of claim 13, wherein the controller is configured to control the supply of the gas through the top vent at a flow rate of at least 170 standard liters per minute. The system of claim 13 , wherein the first period of time is 0-10 seconds.

18. The system of claim 13, wherein the first period of time is less than 1 second.

19. The system of claim 13, wherein the second period of time is 1-60 seconds.

20. The system of claim 13, wherein the second period of time is less than 10 seconds.

21. The system of claim 13, wherein the third period of time is 0.5-1.5 seconds.

22. The system of claim 13, wherein the controller is configured to repeatedly perform (a), (b), and (c).

23. The system of claim 13, wherein: During the first period, the controller is configured to open a fourth valve in fluid communication with the gas source to supply the gas through a third vent into the gas volume of the load lock.

24. The system of claim 23, wherein the controller is configured to alternately open the first valve and the fourth valve during the first period.

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