Patent Publication Number: US-11661654-B2

Title: Substrate processing systems including gas delivery system with reduced dead legs

Description:
FIELD 
     The present disclosure relates to substrate processing systems, and more particularly to gas delivery systems for substrate processing systems including reduced dead legs. 
     BACKGROUND 
     The background description provided here is for the purpose of generally presenting the context of the disclosure. Work of the presently named inventors, to the extent it is described in this background section, as well as aspects of the description that may not otherwise qualify as prior art at the time of filing, are neither expressly nor impliedly admitted as prior art against the present disclosure. 
     Substrate processing systems for performing deposition and/or etching typically include a processing chamber with a pedestal. A substrate such as a semiconductor wafer may be arranged on the pedestal during processing. A process gas mixture including one or more precursors may be introduced into the processing chamber to deposit film on the substrate or to etch the substrate. In some substrate processing systems, radio frequency (RF) plasma can be struck in the processing chamber and/or an RF bias on the pedestal may be used to activate chemical reactions. 
     Various gas flow paths in the gas delivery system are used to deliver process gases, carrier gases, oxidizing gases, precursor gases and/or purge gases to the processing chamber. The gas flow paths are defined by via tubing, valves, manifolds and gas flow channels in a valve inlet block. Gas may be delivered by a gas flow channel during one portion of the process and gas may not be delivered during other portions of the process. In other words, gas such as a vaporized precursor gas may remain in the gas flow channel temporarily unless a purge process is performed to clear the gas flow channel. Portions of gas flow channels that hold stagnant gases are called dead legs. Stagnant gas in the dead legs may decompose and cause defects on the substrate. 
     SUMMARY 
     A gas delivery system for a substrate processing system includes a 2-port valve including a first port and a second port and a first valve located between the first port and the second port. A 4-port valve includes a first port, a second port, a third port and a fourth port. A first node is connected to the first port and the second port. A bypass path is located between the third port and the fourth port. A second node is located along the bypass path between the third port and the fourth port. A second valve is located between the first node and the second node. A manifold block defines gas flow channels configured to connect the first port of the 4-port valve to a first inlet, configured to connect the second port of the 4-port valve to the first port of the 2-port valve, configured to connect the third port of the 4-port valve to a second inlet, configured to connect the second port of the 2-port valve to a first outlet, and configured to connect the fourth port of the 4-port valve to a second outlet. 
     In other features, gas delivery system includes a first gas source, a second gas source; a manifold connected to the first inlet. A third valve selectively connects the first gas source to the manifold. A fourth valve selectively connects the second gas source to the manifold. 
     In other features, the first gas source supplies a push gas, the second gas source supplies a dose gas, and the second outlet is connected to a processing chamber. The dose gas source includes an ampoule supplying vaporized precursor. 
     In other features, the gas delivery system further includes a controller configured to set states of the first valve, the second valve, the third valve and the fourth valve in a diverting mode. During the diverting mode, the first valve is open, the second valve is closed, the third valve is open and the fourth valve is closed. 
     In other features, the controller is further configured to set the states of the first valve, the second valve, the third valve and the fourth valve in a dosing mode after the diverting mode. During the dosing mode, the first valve is closed, the second valve is open, the third valve is open and the fourth valve is open. 
     In other features, a dead leg is created between the first node and an inlet of the first valve during the dosing period. The dead leg defines a volume less than 2.5 ml. There is no deadleg volume during the diverting mode. 
     A substrate processing system includes a processing chamber including a gas distribution device connected to the first outlet of the manifold of the gas delivery system, a substrate support, and an RF generator. A controller is configured to strike plasma between the gas distribution device and the substrate support during a dosing mode. 
     A gas delivery system for a substrate processing system includes a first 3-port valve including a first port, a second port, a third port, a bypass path and a first node. A first valve is located between the second port and the first node. The bypass path and the first node are located between the first port and the third port. The gas delivery system includes a second 3-port valve including a first port, a second port, a third port, a second node, and a bypass path. A second valve is located between the first port and the second node. The bypass path and the second node are located between the second port and the third port. A manifold block defines gas flow channels configured to connect the first port of the first 3-port valve to a first inlet, configured to connect the second port of the first 3-port valve to a first outlet, configured to connect the second port of the second 3-port valve to a second inlet, configured to connect the third port of the first 3-port valve to the first port of the second 3-port valve, and configured to connect the third port of the second 3-port valve to a second outlet. 
     In other features, the gas delivery system further includes a first gas source, a second gas source, a manifold connected to the first port of the first 3-port valve, a third valve selectively connecting the first gas source to the manifold, and a fourth valve selectively connecting the second gas source to the manifold. 
     In other features, the first gas source supplies a push gas, the second gas source supplies a dose gas, and the second outlet is connected to a processing chamber. 
     In other features, a controller is configured to control the first valve, the second valve, the third valve and the fourth valve into a diverting mode. During the diverting mode, the first valve is open, the second valve is closed, the third valve is open and the fourth valve is closed. 
     In other features, the controller is further configured to control the first valve, the second valve, the third valve and the fourth valve in a dosing mode after the diverting mode. During the dosing mode, the first valve is closed, the second valve is open, the third valve is open and the fourth valve is open. 
     In other features, a dead leg is created between the first node and an inlet of the second valve. The dead leg occurs during the diverting mode. The dose gas source includes an ampoule supplying vaporized precursor. The dead leg defines a volume less than 2.5 ml. 
     A substrate processing system includes a processing chamber including a gas distribution device connected to the first outlet of the gas delivery system, a substrate support, and an RF generator. A controller is configured to strike plasma between the gas distribution device and the substrate support during dosing. 
     Further areas of applicability of the present disclosure will become apparent from the detailed description, the claims and the 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 
       The present disclosure will become more fully understood from the detailed description and the accompanying drawings, wherein: 
         FIG.  1    is a functional block diagram of an example of a substrate processing system according to the present disclosure; 
         FIG.  2    is a perspective view of an example of a gas delivery assembly according to the prior art; 
         FIG.  3    is a schematic view of an example of a first valve assembly of a gas delivery system including two 3-port valves; and 
         FIG.  4    is a schematic view of an example of the first valve assembly of  FIG.  3    during a diverting portion of a recipe; 
         FIG.  5    is a schematic view of an example of the first valve assembly of  FIG.  3    during a dosing portion of a recipe; 
         FIG.  6    is a perspective view illustrating an example of a valve manifold and valve inlets of the first valve assembly of  FIG.  3   ; 
         FIG.  7    is a schematic view of an example of a second valve assembly for a gas delivery system including a 4-port valve connected to a 2-port valve; and 
         FIGS.  8 A and  8 B  are schematic views of examples of the second valve assembly of  FIG.  7    during divert portions of recipes; 
         FIG.  9    is a schematic view of an example of the second valve assembly of  FIG.  7    during a dosing portion of a recipe; and 
         FIG.  10    is a perspective view illustrating an example of a valve manifold and valve inlets of the second valve assembly of  FIG.  7   ; and 
         FIG.  11    is a timing diagram for operating valves in the first and second valve assemblies of  FIGS.  3  and  7   . 
     
    
    
     In the drawings, reference numbers may be reused to identify similar and/or identical elements. 
     DETAILED DESCRIPTION 
     Several valve assembly arrangements according to the present disclosure significantly reduce defects during substrate processing by reducing dead leg volume when delivering process gas mixtures such as precursor gas and/or vaporized precursor. In a first valve assembly, a combination of two 3-port valves is used to reduce dead leg volume. In a second valve assembly, a combination of a 4-port valve and a 2-port valve are used to reduce dead leg volume. 
     Referring now to  FIG.  1   , an example of a substrate processing system  100  includes a processing chamber  112  with a reaction volume. In some examples, a plasma-enhanced chemical vapor deposition (CVD) or plasma enhanced atomic layer deposition (ALD) process may be performed, although other etching, deposition or other substrate processes may be performed. 
     Process gas mixtures may be supplied to the processing chamber  112  using a gas distribution device  114  such as showerhead. In some examples, the showerhead is a chandelier-type showerhead. A substrate  118  such as a semiconductor wafer may be arranged on a substrate support  116  during processing. The substrate support  116  may include a pedestal, an electrostatic chuck, a mechanical chuck or other type of substrate support. 
     One or more gas delivery systems  120 - 1 ,  120 - 2   120 - 3 , . . . may include one or more gas sources  122 - 1 ,  122 - 2 , . . . , and  122 -N(collectively gas sources  122 ), where N is an integer greater than one. Valves  124 - 1 ,  124 - 2 , . . . , and  124 -N (collectively valves  124 ), mass flow controllers  126 - 1 ,  126 - 2 , . . . , and  126 -N(collectively mass flow controllers  126 ), or other flow control devices may be used to controllably supply one or more gases to a manifold  130 , which supplies a gas mixture via a valve V 46 , a manifold  131 , and a valve V 164  to the processing chamber  112 . In some examples, the manifold  131  is a heated injector manifold. One or more additional gas delivery systems may be provided to supply gases or gas mixtures in other locations. A divert path including a valve V 166  selectively diverts gas to vacuum or exhaust. 
     A controller  140  may be used to monitor process parameters such as temperature, pressure, etc. (using one or more sensors  141 ) and to control process timing. The controller  140  may be used to control process devices such as gas delivery systems  120 - 1 ,  120 - 2  and  120 - 3 , a substrate support heater  142 , and/or an RF plasma generator  146 . The controller  140  may also be used to evacuate the processing chamber  112  using a valve  150  and pump  152 . 
     The RF plasma generator  146  generates the RF plasma in the processing chamber. The RF plasma generator  146  may be an inductive or capacitive-type RF plasma generator. In some examples, the RF plasma generator  146  may include an RF supply  160  and a matching and distribution network  162 . While the RF plasma generator  146  is shown connected to the gas distribution device  114  and the substrate support is grounded or floating, the RF plasma generator  146  can be connected to the substrate support  116  and the gas distribution device  114  can be grounded or floating. 
     Vaporized precursor can be supplied to the manifold  131  by an ampoule  190  that supplies vaporized liquid precursor. A carrier gas  180  is supplied via valve  182 , MFC  184 , and valve  186 . Additional valves V 213 , V 205 , V 214  and V 55  control delivery of the carrier gas and/or delivery of the carrier gas and vaporized precursor from the ampoule  190 . In some examples, the ampoule  190  is heated by a heater  194 . The ampoule  190  may further include one or more temperature sensors  192  to detect a temperature of the precursor liquid in the ampoule  190 . The controller  140  may be used to sense the temperature of the precursor liquid and to control the heater  194  to heat the precursor liquid to a predetermined temperature. 
     As can be appreciated, when valve V 213  is closed and valves V 205  and V 214  are open, carrier gas flows through the ampoule  190  and entrains vaporized precursor. The mixture of carrier gas and vaporized precursor is delivered by valve V 55  to the manifold  131  and by the valve V 164  to the gas distribution device  114 . In some examples, a gas delivery system  120 - 2  delivers a gas mixture to a manifold  196  and valves V 44  and V 165  control delivery of the gases to the processing chamber. In some examples, a valve V 162  provides a secondary purge gas mixture to the stem of the showerhead. In some examples, a gas delivery system  120 - 3  delivers gases to a manifold  198  and valves V 69  and V 167  control delivery of the gases to vacuum, exhaust or the processing chamber. 
     Referring now to  FIG.  2   , a gas delivery assembly  200  is shown to include one or more valve assemblies  220 - 1 ,  220 - 2  . . . and  220 - 4  (collectively valve assemblies  220 ) and a valve manifold  228 . The valve assemblies  220  are configured to control the flow of fluid(s) into and out of the valve manifold  228 . In this regard, the valve manifold  228  includes a body  274  defining one or more gas channels  276 - 1 ,  276 - 2  . . . and  276 -N (collectively gas channels  276 ), first, second and third inlets  278 ,  280 ,  282 , and first and second outlets  284 ,  285 . 
     The first gas channel  276 - 1  extends from, and fluidly communicates with, the first inlet  278  of the valve manifold  228  and the second valve assembly  220 - 2 . The second gas channel  276 - 2  extends from the first gas channel  276 - 1  to the first valve assembly  220 - 1 . The third gas channel  276 - 3  extends from the first valve assembly  220 - 1  to the first outlet  284  of the valve manifold  228 . The fourth gas channel  276 - 4  extends from the second valve assembly  220 - 2  to the second outlet  285  of the valve manifold  228 . 
     The gas delivery assembly  200  is operated in at least three modes, such as a divert mode, a supply mode, and a standby mode. The gas delivery assembly  200  may operate in a continuous cycle such that the divert mode precedes the supply mode, the supply mode precedes the standby mode, and the standby mode precedes the divert mode. In the divert mode, stale precursor in the gas channels  276  may be replaced with fresh precursor. In the supply mode, vaporized precursor is supplied to the processing chamber. In the standby mode, vaporized precursor is not supplied and is not diverted. 
     When supplying vaporized precursor, the first valve assembly  220 - 1  is closed and the second valve assembly  220 - 2  is open. The vaporized precursor gas is supplied through the first gas channel  276 - 1  from the first inlet  278  to the second valve assembly  220 - 2 . The vaporized precursor gas flows through the second valve assembly  220 - 2  and the fourth gas channel  276 - 4  to the processing chamber or other portion of the substrate processing system. 
     During the standby mode, the first and second valve assemblies  220 - 1 ,  220 - 2  are closed such that flow of vaporized precursor from the first inlet  278  is prevented. Accordingly, during the standby mode, vaporized precursor gas remains in the first gas channel  276 - 1 . In some conditions, the stagnant vaporized precursor in the first gas channel  276 - 1  may condense into particles. Stagnant vaporized precursor that later enters the processing chamber can cause defects. 
     Prior to supplying vaporized precursor to the processing chamber in the supply mode, the vaporized precursor is diverted and discarded such that the stale vaporized precursor in the gas channel  276 - 1  is replaced by fresh precursor. When diverting the vaporized precursor, the first valve assembly  220 - 1  is open and the second valve assembly  220 - 2  is closed. When vaporized precursor gas is supplied through the first gas channel  276 - 1  from the first inlet  278 , the vaporized precursor gas flows out of the valve manifold  228  through the second gas channel  276 - 2 , the first valve assembly  220 - 1  and the third gas channel  276 - 3 . 
     While the divert mode provides some improvement, not all of the stale vaporized precursor is removed. The gas delivery assembly  200  has a dead-leg volume  290  that is located downstream from the second gas channel  276 - 2  and upstream from the second valve assembly  220 - 2 . Specifically, the vaporized precursor that stagnates in the dead-leg volume during the standby mode is not diverted through the first valve assembly  220 - 1  during the divert mode. Vaporized precursor that was trapped in the dead-leg volume  290  during the divert mode still flows into the processing chamber from the first and fourth gas channels  276 - 1 ,  276 - 4  during the supply mode and creates defects in the substrate. 
     Referring now to  FIG.  3   , a first valve assembly  300  for a gas delivery system includes a first 3-port valve  302  and a second 3-port valve  304 . The first 3-port valve  302  includes a first port receiving gas from an outlet of the manifold  131 . The first port is connected to a bypass path  330  and to a first node  310 . A second port (or divert path  320 ) of the first 3-port valve  302  is connected through a first valve V 166 A to the first node  310  (valved path  332 ). A third port is connected to the bypass path  330  and to the first node  310 . 
     A first port of the second 3-port valve  304  is connected by a valved path  342  through a second valve V 164 A to a second node  314 . A second port of the second 3-port valve  304  supplies gas such as push gas and is connected to a bypass path  340  and to the second node  314 . A third port is connected to the bypass path  340  and to the second node  314 . The third port is connected to the processing chamber. 
     Referring now to  FIG.  4   , the first valve assembly  300  is shown in a diverting mode. The valve V 46  supplies gas through the manifold  131  (and the valve V 55  to the ampoule  190  is closed). The gas delivered to the first port of the first 3-port valve  302  is diverted at the first node  310  through the first valve V 166 A. The second 3-port valve  304  is closed. A dead leg occurs between the first node  310  and the inlet of the second valve V 164 A. 
     Referring now to  FIG.  5   , the first valve assembly  300  is shown during a dosing mode. The valve V 46  supplies gas through the manifold  131  (and the valve V 55  to the ampoule  190  is open). The vaporized precursor gas mixture from the ampoule  190  is delivered to the first port of the first 3-port valve  302  and is not diverted at the first node  310  by the first valve V 166 A (which is closed). Rather, the vaporized precursor gas mixture is delivered to the first port of the second 3-port valve  304  (the second valve V 164 A is open) to the second node  314 . The mixture of the push gas and the vaporized precursor is delivered to the processing chamber. 
     In some examples, the valve assembly  300  defines a very small volume between the first node  310  and the inlet of the second valve V 164 A. In some examples, the volume is less than 4 ml. In some examples, the volume is less than 3 ml. In other examples, the volume is 2.3 ml. The dose flow to the processing chamber travels through the first and second valves V 166 A and V 164 A, respectively. The flow to the processing chamber expands out of the second valve V 164 A into an inert stream from the manifold  198 . During the diverting step, a section between the first and second valves V 166 A and V 164 A is not purged. During the dosing step, the section between the first and second valves V 166 A and V 164 A is purged to the processing chamber. 
     Referring now to  FIG.  6   , a portion of the first valve assembly is shown to include a valve manifold block  610  and valve inlets  600  of the first and second 3-port valves  302  and  304 , respectively. The valve manifold block  610  defines a first channel  620  connecting the first port of the first 3-port valve  302  and the ampoule  190 . The valve manifold block  610  defines a second channel  624  connecting to the second port of the first 3-port valve  302  to the diverting path  320 . The valve manifold block  610  defines a third channel  630  connecting the third port of the first 3-port valve  302  to the first port of the second 3-port valve  304 . The valve manifold block  610  defines a fourth channel  636  that connects the manifold  198  to the second port of the second 3-port valve  304 . The valve manifold block  610  defines a fifth channel  632  connecting the third port of the second 3-port valve  304  to the processing chamber. 
     Referring now to  FIG.  7   , a second valve assembly  700  includes a 2-port valve  702  and a 4-port valve  704 . The 2-port valve  702  includes a first port receiving gas from an outlet of the manifold  131  via a first node  710  of the 4-port valve  704 . A second port of the 2-port valve  702  is connected to a divert path  720 . A first valve V 166 B is located between the first and second ports of the 2-port valve  702 . 
     The 4-port valve  704  includes a first port connected to the manifold  131  and to the first node  710 . A second port of the 4-port valve  704  connects the first node  710  to the first port of the 2-port valve  702 . The first node  710  is connected to the second valve V 164 B of the 4-port valve  704 . A third port of the 4-port valve  704  receives gas such as push gas from the manifold  198  and is connected to the second node  714 . A fourth port of the 4-port valve  704  connects the second node  714  to the processing chamber. The 4-port valve  704  includes a bypass path  730  and a valved path  732 . The second valve V 164 B selectively allows flow from the first node  710  to the second node  714  or blocks the flow. 
     As can be seen in  FIG.  7   , the first port of the 4-port valve  704  connects to a valved path  732  (at the first node  710 ) at an angle  760  relative to a path of the valved path  732 . The second node of the 4-port valve  704  connects at an angle  762  relative to the first path. In some examples, the angle  760  is an acute angle that is greater than zero. In some examples, the angle  760  is greater than zero and less than 45 degrees. In some examples, the angle  762  is greater than the angle  760 . In some examples, the angle  762  is greater than 60 degrees and less than 120 degrees. In some examples, the angle  762  is greater than 70 degrees and less than 100 degrees. 
     Referring now to  FIGS.  8 A and  8 B , the second valve assembly  700  is shown during two example diverting modes. In  FIG.  8 A , the valve V 46  supplies gas through the manifold  131  (and the valve V 55  to the ampoule  190  is closed). The gas is delivered to the first port of the 4-port valve  704  (which includes the second valve V 164 B that is closed). The gas flows through the first node  710  and out the second port of the 4-port valve  704  to the first port of the 2-port valve  702 . The first valve V 166 B of the 2-port valve  702  is open so the gas flows through the 2-port valve  702  to the diverting path  720 . 
     In  FIG.  8 B , the valve V 46  supplies gas from a first gas source through the manifold  131  (and the valves V 213  and V 55  are open and V 205  and V 214  are closed). The push and carrier gas are delivered from a second gas source to the first port of the 4-port valve  704  (which includes the second valve V 164 A that is closed). The gas flows through the first node  710  and out the second port of the 4-port valve  704  to the first port of the 2-port valve  702 . The first valve V 166 B of the 2-port valve  702  is open so the gas flows through the 2-port valve  702  to the diverting path  720 . 
     In both  FIGS.  8 A and  8 B , during the divert mode, the deadleg volume is zero for the second valve assembly  700 . In some examples, internal passages of the 4 port valve are cut at an angle in contrast to conventional valves having internal passages that are straight or parallel sections. 
     Referring now to  FIG.  9   , the second valve assembly  700  is shown during dosing operation. The valve V 46  supplies gas through the manifold  131  (and the valve V 55  to the ampoule  190  is open). The vaporized precursor gas mixture delivered to the first port of the 4-port valve  704  is not diverted at the first node  710  (since the first valve V 166 B is closed). Rather, the vaporized precursor gas mixture is delivered to the inlet of the 4-port valve  704  (via the second valve V 164 B which is open) and then to the second node  714 . The mixture of the push gas and the vaporized precursor is delivered to the processing chamber. A dead leg occurs during dosing between the first node  710  and the inlet of the first valve V 166 B. 
     Referring now to  FIG.  10   , a portion of the second valve assembly is shown to include a valve manifold block  1000  and valve inlets  1004  to the 2-port and 4-port valves  702  and  704 , respectively. The valve manifold block  1000  defines a first channel  1010  that connects to the second port of the 2-port valve  702 . The valve manifold block  1000  defines a second channel  1020  connecting the first port of the 2-port valve  702  to a first port of the 4-port valve  704 . The valve manifold block  1000  defines a third channel  1050  (receiving dose and carrier gas) connected to the first port of the 4-port valve  704 . The valve manifold block  1000  defines a fourth channel  1040  connected to the third port of the 4-port valve  704  (receiving push gas). The valve manifold block  1000  defines a fifth channel  1030  connected to the fourth port of the 4-port valve  704  (directing gases to the processing chamber). 
     In some examples, the second valve assembly  700  defines a very small volume between the first node  710  and the inlet of the first valve V 166 B. In some examples, the volume is less than 4 ml. In some examples, the volume is less than 3 ml. In other examples, the volume is 2.3 ml. Unlike the first valve assembly  300 , the dose flow of the second valve assembly  700  to the processing chamber travels through one valve (the second valve V 164 B). The flow to the processing chamber expands out of center port into a plenum. During the diverting step, the dead leg is cleared. During the dosing step, the gas is trapped in the dead leg. 
     Referring now to  FIG.  11   , a timing diagram is shown for operating valves using the first and second valve assemblies  300  and  700 , respectively. While specific values for switching periods are shown, other periods can be used. During a soak period, a first gas mixture from a manifold is supplied to the processing chamber using the second valve V 164 . During a diverting period including LCD 1  and LCD 2 , the second valve V 164  is closed and the first valve V 166  is open. During LCD 1 , the valve V 213  is open to supply push gas. During LCD 2 , the valve V 213  is closed and the valves V 205 , V 214  and V 55  are opened to supply vaporized precursor. In some examples, the period of LCD 1  is 1.5 s and the period of LCD 2  is 1.5 s. 
     During Part1 of a dose period, the valves V 205 , V 214  and V 55  remain open. During Part1 and Part2 of the dosing period, the valve V 166  is closed and V 164  is open. The duration of Part1 will depend on gas transport times and in some examples the period is 0.05 s. In some examples, the duration of Part2 is 0.2 s. After dosing, the valve V 166  is opened and the valve V 164  is closed. 
     The foregoing description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure can be implemented in a variety of forms. Therefore, while this disclosure includes particular examples, the true scope of the disclosure should not be so limited since other modifications will become apparent upon a study of the drawings, the specification, and the following claims. It should be understood that one or more steps within a method may be executed in different order (or concurrently) without altering the principles of the present disclosure. Further, although each of the embodiments is described above as having certain features, any one or more of those features described with respect to any embodiment of the disclosure can be implemented in and/or combined with features of any of the other embodiments, even if that combination is not explicitly described. In other words, the described embodiments are not mutually exclusive, and permutations of one or more embodiments with one another remain within the scope of this disclosure. 
     Spatial and functional relationships between elements (for example, between modules, circuit elements, semiconductor layers, etc.) are described using various terms, including “connected,” “engaged,” “coupled,” “adjacent,” “next to,” “on top of,” “above,” “below,” and “disposed.” Unless explicitly described as being “direct,” when a relationship between first and second elements is described in the above disclosure, that relationship can be a direct relationship where no other intervening elements are present between the first and second elements, but can also be an indirect relationship where one or more intervening elements are present (either 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.” 
     In some implementations, a controller is part of a system, which may be part of the above-described examples. Such systems can comprise semiconductor processing equipment, including a processing tool or tools, chamber or chambers, a platform or platforms for processing, and/or specific processing components (a wafer pedestal, a gas flow system, etc.). These systems may be integrated with electronics for controlling their operation before, during, and after processing of a semiconductor wafer or substrate. The electronics may be referred to as the “controller,” which may control various components or subparts of the system or systems. The controller, depending on the processing requirements and/or the type of system, may be programmed to control any of the processes disclosed herein, including the delivery of processing 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, positional and operation settings, wafer transfers into and out of a tool and other transfer tools and/or load locks connected to or interfaced with a specific system. 
     Broadly speaking, the controller may be defined as electronics having various integrated circuits, logic, memory, and/or software that receive instructions, issue instructions, control operation, enable cleaning operations, enable endpoint measurements, and the like. The integrated circuits may include chips in the form of firmware that store 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). Program instructions may be instructions communicated to the controller in the form of various individual settings (or program files), defining operational parameters for carrying out a particular process on or for a semiconductor wafer or to a system. The operational parameters may, in some embodiments, be part of a recipe defined by process engineers to accomplish one or more processing steps during the fabrication of one or more layers, materials, metals, oxides, silicon, silicon dioxide, surfaces, circuits, and/or dies of a wafer. 
     The controller, in some implementations, may be a 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 may be in the “cloud” or all or a part of a fab host computer system, which can allow for remote access of the wafer processing. The computer may enable remote access to the system to monitor current progress of fabrication operations, examine a history of past fabrication operations, examine trends or performance metrics from a plurality of fabrication operations, to change parameters of current processing, to set processing steps to follow a current processing, or to start a new process. In some examples, a remote computer (e.g. a server) can provide process recipes to a system over a network, which may include a local network or the Internet. The remote computer may include a user interface that enables entry or programming of parameters and/or settings, which are then communicated to the system from the remote computer. In some examples, the controller receives instructions in the form of data, which specify parameters for each of the processing steps to be performed during one or more operations. It should be understood that the parameters may be specific to the type of process to be performed and the type of tool that the controller is configured to interface with or control. Thus as described above, the controller may be distributed, such as by comprising one or more discrete controllers that are networked together and working towards a common purpose, such as the processes and controls described herein. An example of a distributed controller for such purposes would be one or more integrated circuits on a chamber in communication with one or more integrated circuits located remotely (such as at the platform level or as part of a remote computer) that combine to control a process on the processing chamber. 
     Without limitation, example systems may include a plasma etch chamber or module, a deposition chamber or module, a spin-rinse chamber or module, a metal plating chamber or module, a clean chamber or module, a bevel edge etch chamber or module, a physical vapor deposition (PVD) chamber or module, a chemical vapor deposition (CVD) chamber or module, an atomic layer deposition (ALD) chamber or module, an atomic layer etch (ALE) chamber or module, an ion implantation chamber or module, a track chamber or module, and any other semiconductor processing systems that may be associated or used in the fabrication and/or manufacturing of semiconductor wafers. 
     As noted above, depending on the process step or steps to be performed by the tool, the controller might communicate with one or more of other tool circuits or modules, other tool components, cluster tools, other tool interfaces, adjacent tools, neighboring tools, tools located throughout a factory, a main computer, another controller, or tools used in material transport that bring containers of wafers to and from tool locations and/or load ports in a semiconductor manufacturing factory.