Patent Publication Number: US-2023154766-A1

Title: Pre-clean chamber assembly architecture for improved serviceability

Description:
BACKGROUND 
     Field 
     Embodiments of the present disclosure generally relate to a system for substrate processing. More specifically, embodiments described herein relate to a system for performing a pre-clean process on substrates for semiconductor processing. 
     Description of the Related Art 
     Pre-cleaning of a substrate is performed either before or between substrate processing operations. Pre-cleaning of a substrate reduces the contamination of the substrate and may remove unwanted residue or materials from a surface of the substrate before processing operations are performed. Pre-clean chambers are attached to a portion of a processing tool, such as a linear or cluster tool. Once the pre-clean chambers are attached to the processing tool, substrates are run through the pre-clean chamber during processing operations. The volume inside of a pre-clean chamber is in fluid communication with a volume inside of at least a portion of the processing tool, such as a transfer chamber. 
     Current semiconductor manufacturing facilities utilize an increasing number of processing tools as technology evolves. Maintenance of each of the processing tools after installation is performed to enable improved long-term processing results. Maintenance of pre-clean chambers is performed to improve cleaning performance. Maintenance is often difficult to perform due to space constraints between processing tools. Therefore, the maintenance often requires prolonged tool down-time, which increases the overall cost of ownership and decreases the usability of the tool. Previous attempts to reduce the maintenance times and cost have led to increased chamber footprints. The footprint and serviceable area of processing tools are therefore limiting factors in the quantity and type of tools utilized within semiconductor manufacturing facilities. 
     Therefore, what is needed in the art are processing tools with decreased footprints and improve accessible maintenance points. 
     SUMMARY 
     The present disclosure generally relates to apparatus for processing a substrate, such as apparatus suitable for use in semiconductor manufacturing. In one embodiment, the apparatus includes a transfer chamber, a factory interface coupled to a first side of the transfer chamber, a plurality of process chambers coupled to the a second side of the transfer chamber, and a pre-clean process module coupled to the a third side of the transfer chamber between the factory interface and at least one of the plurality of process chambers. The pre-clean process module includes a pre-clean chamber and a gas panel disposed below the pre-clean chamber. A pre-clean control module is disposed separate from the pre-clean process module and adjacent to one of the plurality of process chambers. The pre-clean control module includes a power supply and a controller. A cable conduit is disposed between the pre-clean process module and the pre-clean control module. 
     In another embodiment, a pre-clean assembly suitable for use in semiconductor manufacturing is described. The pre-clean assembly includes a pre-clean process module. The pre-clean process module includes a pre-clean chamber comprising a lid, a substrate support pedestal, and a plate stack. The lid is rotatable about an axis of rotation. A gas panel is disposed below the pre-clean chamber. An isolation port is disposed on a first side of the pre-clean process module and extends in a first direction. A manometer is disposed on the first side and extends in the first direction. A pre-clean control module is disposed separate from the pre-clean process module and includes a power supply and a controller. A cable conduit is disposed between the pre-clean process module and the pre-clean control module. The cable conduit has a length of greater than about 400 mm. 
     In yet another embodiment, an apparatus for substrate processing suitable for use in semiconductor manufacturing is described. The apparatus includes a transfer chamber, a factory interface coupled to a first side of the transfer chamber, four process chambers coupled to the transfer chamber, a first pre-clean process module coupled to a second side of the transfer chamber between the factory interface and a first of the process chambers. The first pre-clean process module includes a pre-clean chamber and a gas panel disposed below the pre-clean chamber. The pre-clean chamber is coupled to the transfer chamber and further includes a lid with an axis of rotation adjacent to the transfer chamber, such that the lid rotates towards the transfer chamber when opening. A first pre-clean control module is disposed separate from the first pre-clean process module and adjacent to the first of the process chambers. The first pre-clean control module includes a power supply and a controller configured to control a pre-clean process within the pre-clean chamber. A first cable conduit is disposed between the first pre-clean process module and the first pre-clean control module and is configured to hold one or more electric cables and one or more control cables therein. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features of the present disclosure can be understood in detail, a more particular description of the disclosure, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this disclosure and are therefore not to be considered limiting of its scope, for the disclosure may admit to other equally effective embodiments. 
         FIG.  1    illustrates a schematic plan view of a cluster tool assembly for processing a substrate, according to embodiments described herein. 
         FIG.  2    illustrates a schematic front isometric view of a first pre-clean process module, according to embodiments described herein. 
         FIG.  3 A  illustrates a schematic front isometric view of a first pre-clean control module, according to embodiments described herein. 
         FIG.  3 B  illustrates a schematic cross-sectional side view of a first cable conduit, according to embodiments described herein. 
         FIG.  4    illustrates a schematic front isometric view of a pre-clean chamber with an open lid, according to embodiments described herein. 
         FIG.  5 A  illustrates a schematic plan view of a part of the cluster tool assembly of  FIG.  1    and a maintenance passage, according to embodiments described herein. 
         FIG.  5 B  illustrates a schematic side view of the maintenance passage of  FIG.  5 A  between a first pre-clean process module and a first pre-clean control module. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments described in the present disclosure generally relate to a system for substrate processing. More specifically, embodiments described herein relate to a system for performing a pre-clean process on substrates for semiconductor processing. The system for pre-clean processing includes a pre-clean chamber as well as supporting apparatus. The supporting apparatus include a gas panel and a pre-clean control module. The pre-clean control module includes power supply and a controller. A cable conduit connects the pre-clean module to the pre-clean chamber and one or more electrical or control cables pass through the cable conduit. The pre-clean chamber and the gas panel form a pre-clean process module. The pre-clean process module is separate from the pre-clean control module to enable the footprints of the pre-clean process module and the pre-clean control module to be separated and a maintenance passage to be formed when in combination with a cluster tool. Separating the pre-clean process module and the pre-clean control modules reduces the footprint of the pre-clean process module and enables improved maintenance pathways around both the pre-clean process module and the pre-clean control module. The cable conduit attaching the pre-clean process module and the pre-clean control module enables the distance between the pre-clean process module and the pre-clean control module to be increased while shielding a plurality of power cables and a plurality of control cables from outside interference and interference with each other. 
       FIG.  1    illustrates a schematic plan view of a cluster tool assembly  100  for processing a substrate. The cluster tool assembly  100  includes one or more pre-clean process modules  106   a ,  106   b  and one or more pre-clean control modules  112   a ,  112   b . The pre-clean process modules  106   a ,  106   b  are coupled to an outer surface of a transfer chamber  102 . A plurality of process chambers  104   a - 104   d  are further coupled to the outer surface of the transfer chamber  102 . In the embodiment of  FIG.  1   , there are two pre-clean process modules  106   a ,  106   b  and four process chambers  104   a - 104   d . One or more load lock chambers  110  are disposed between the transfer chamber  102  and a front end factory interface (FI)  108 . A single load lock chamber  110  is disposed between the transfer chamber  102  and the front end FI  108  of  FIG.  1   . A substrate is passed through the load lock chamber  110  when being transferred from the front end FI  108  to the transfer chamber  102  and from the transfer chamber  102  to the front end FI  108 . 
     The load lock chamber  110  is connected to a vacuum pump (not shown), for example a roughing pump, the output of which is connected to an exhaust duct (not shown), to reduce the pressure within the load lock chamber  110  to a sub-atmospheric pressure on the order of about 10 −3  torr. The load lock chamber  110  may be connected to a vacuum pump dedicated thereto, or a vacuum pump shared with one or more components within the cluster tool assembly  100 , or to a house exhaust other than a vacuum pump to reduce the pressure therein. In each case, valves are disposed on either end of the load lock chamber  110 . 
     A first valve  111  is disposed between the load lock chamber  110  and the front end FI  108 . A second valve  113  is disposed between the load lock chamber  110  and the transfer chamber  102 . The first valve  111  enables a seal to be formed between the front end FI  108  and the load lock chamber  110  while the load lock chamber  110  is being de-pressurized. The first valve  111  further prevents the transfer chamber  102  from being exposed to atmospheric or ambient pressure conditions while the second valve  113  is open and a substrate is being transferred to the load lock chamber  110  from the transfer chamber  102  or from the transfer chamber  102  to the load lock chamber  110 . The second valve  113  enables a seal to be formed between the transfer chamber  102  and the load lock chamber  110  while the load lock chamber  110  is pressurized or in fluid communication with the front end FI  108 . The second valve  113  prevents the transfer chamber  102  from being exposed to atmospheric or ambient pressure conditions while the first valve  111  is open and a substrate is being transferred to the load lock chamber  110  from the front end FI  108  or from the front end FI  108  to the load lock chamber  110 . 
     The transfer chamber  102  is configured to transfer one or more substrates between each of the load lock chamber  110 , the pre-clean process module  106   a ,  106   b , and the process chambers  104   a - 104   d . As shown herein, the transfer chamber  102  includes seven sidewalls, such that the transfer chamber  102  has a heptagonal cross-sectional outline. The transfer chamber  102  may alternatively have a pentagonal, an enneagonal, or a hendecagonal cross-sectional outline to enable additional process chambers to be coupled to the transfer chamber  102 . The sidewall of the transfer chamber  102  on which the load lock chamber  110  is attached has a reduced thickness when compared to the sidewalls along which any of the process chambers  104   a - 104   d  or the pre-clean process modules  106   a ,  106   b  are attached. The transfer chamber  102  may include a transfer robot  203  or a carousel (not shown) for moving a substrate therein. The transfer robot or carousel has one or more blades (not shown) for holding the substrate and is actuated around a central axis (not shown) of the transfer chamber  102 . A transfer volume within the transfer chamber  102  is held at a vacuum during substrate processing, such as on the order of about 10 −3  Torr or less. 
     Each of the process chambers  104   a - 104   d  are coupled to the outside surface of the transfer chamber  102 . The process chambers  104   a - 104   d  may be four process chambers  104   a - 104   d , such that there is a first process chamber  104   a , a second process chamber  104   b , a third process chamber  104   c , and a fourth process chamber  104   d . However, more or less process chambers are also contemplated. Each of the plurality of process chambers  104   a - 104   d  may be a deposition chamber, such as an epitaxial deposition chambers or other types of deposition chambers. In some embodiments, the process chambers  104   a - 104   d  include at least one of an atomic layer deposition (ALD), a chemical vapor deposition (CVD), or a physical vapor deposition (PVD) chamber. Each of the process chambers  104   a - 104   d  are disposed on a wall adjacent to at least one additional process chamber  104   a - 104   d.    
     In the embodiment of  FIG.  1   , load lock chamber  110  is coupled to a first wall of the transfer chamber  102 . The first pre-clean process module  106   a  is coupled to a second wall of the transfer chamber  102 . The first process chamber  104   a  is coupled to a third wall of the transfer chamber  102 . The second process chamber  104   b  is coupled to a fourth wall of the transfer chamber  102 . The third process chamber  104   c  is coupled to a fifth wall of the transfer chamber  102 . The fourth process chamber  104   d  is coupled to a sixth wall of the transfer chamber  102 . The second pre-clean process module  106   b  is coupled to a seventh wall of the transfer chamber  102 . 
     The walls of the transfer chamber  102  to which the first pre-clean process module  106   a  and the second pre-clean process module  106   b  are coupled are shorter in width than the walls of the transfer chamber  102  to which the process chambers  104   a - 104   d  are coupled. Therefore, the second wall and the seventh wall of the transfer chamber  102  are shorter in width than each of the third wall, the fourth wall, the fifth wall, or the sixth wall. The wall of the transfer chamber  102  to which the load lock chamber  110  is coupled is also shorter in width than the walls of the transfer chamber  102  to which the process chambers  104   a ,  104   d  are coupled. Therefore, the first wall of the transfer chamber  102  is shorter in width than each of the third wall, the fourth wall, the fifth wall, or the sixth wall. Having shorter widths of one or each of the first wall, the second wall, and the third wall reduce the overall footprint of the cluster tool assembly  100 , but reduce the space between the pre-clean process modules  106   a ,  106   b  and other components of the cluster tool assembly  100 . 
     The load lock chamber  110  is disposed on the first wall between the first pre-clean process module  106   a  and the second pre-clean process module  106   b . The first pre-clean process module  106   a  is disposed on the second wall between the load lock chamber  110  and the first process chamber  104   a . The second pre-clean process module  106   b  is disposed on the seventh wall between the load lock chamber  110  and the fourth process chamber  104   d . The first process chamber  104   a  is disposed on the third wall between the first pre-clean process module  106   a  and the second process chamber  103   b . The second process chamber  104   b  is disposed on the fourth wall between the first process chamber  104   a  and the third process chamber  104   c . The third process chamber  104   c  is disposed on the fifth wall between the second process chamber  104   b  and the fourth process chamber  104   d . The fourth process chamber  104   d  is disposed on the sixth wall between the third process chamber  104   c  and the second pre-clean process module  106   b.    
     The first pre-clean control module  112   a  is disposed adjacent to the first process chamber  104   a . In some embodiments, the first pre-clean control module  112   a  is coupled to the first process chamber  104   a . The second pre-clean control module  112   b  is disposed adjacent to the fourth process chamber  104   d . In some embodiments, the second pre-clean control module  112   b  is coupled to the fourth process chamber  104   d.    
     Each of the pre-clean process modules  106   a ,  106   b  are configured to perform a pre-clean process on one or more substrates disposed therein. The pre-clean process may include a plasma etch process. A pre-clean process module  106   a ,  106   b  is disposed on either side of the load lock chamber  110 , such that a first pre-clean process module  106   a  is disposed on one side of the load lock chamber  110  and a second pre-clean process module  106   b  is disposed on an opposite side of the load lock chamber  110  from the first pre-clean process module  106   a . The pre-clean process modules  106   a ,  106   b  are coupled to a side of the transfer chamber  102  and are configured to be in fluid communication with the transfer volume within the transfer chamber  102 . Each of the pre-clean process modules  106   a ,  106   b  is coupled to a pre-clean control module  112   a ,  112   b  by one or more cable conduits  114   a ,  114   b . The first pre-clean process module  106   a  is coupled to a first pre-clean control module  112   a  by a first cable conduit  114   a . The second pre-clean process module  106   b  is coupled to a second pre-clean control module  112   b  by a second cable conduit  114   b.    
     Each of the pre-clean process modules  106   a ,  106   b  includes a manometer  116   a ,  116   b , an isolation port  118   a ,  118   b , and a throttle valve  120   a ,  120   b  extending from an outward facing surface  115   a ,  115   b  of the pre-clean process modules  106   a ,  106   b . Therefore, a first manometer  116   a , a first isolation port  118   a , and a first throttle valve  120   a  extend from an outward facing surface  115   a  of the first pre-clean process module  106   a . A second manometer  116   b , a second isolation port  118   b , and a second throttle valve  120   b  extend from an outward facing surface  115   b  of the second pre-clean process module  106   b . Each of the manometers  116   a ,  116   b , the isolation ports  118   a ,  118   b , and the throttle valves  120   a ,  120   b  extend from a single side of each pre-clean process modules  106   a ,  106   b  to enable improved access to each of the manometers  116   a ,  116   b , the isolation ports  118   a ,  118   b , and the throttle valves  120   a ,  120   b.    
     A mainframe power supply  122  is disposed adjacent to the front end FI  108  and the load lock chamber  110 . The mainframe power supply  122  may be configured to supply alternating current (AC) power to the cluster tool assembly  100 , such as to the transfer chamber  102 , the load lock chamber  110 , and the front end FI  108 . The mainframe power supply  122  may further provide power to the process chambers  104   a - 104   d  and/or the pre-clean process modules  106   a ,  106   b . The mainframe power supply  122  may be coupled to the side of the load lock chamber  110  and/or the front end FI  108 . 
       FIG.  2    illustrates a schematic front isometric view of a first pre-clean process module  106   a . The second pre-clean module  106   b  is similar to the first pre-clean module  106   a . The first pre-clean process module  106   a  includes a pre-clean chamber  204 , a gas panel  202 , a plurality of supports  210   a ,  210   b ,  212   c ,  212 , the manometer  116   a , the isolation port  118   a , and the throttle valve  120   a . The pre-clean chamber  204  includes a lid  206 , a body  205 , a hinge assembly  208  coupling the lid  206  and the pre-clean chamber  204 , and a pedestal actuator  222 . The pre-clean chamber  204  is disposed above the gas panel  202 . The gas panel  202  includes a purge gas panel  220  and a process gas panel  218 . 
     The gas panel  202  is disposed below the pre-clean chamber  204  to reduce the footprint of the first pre-clean process module  106   a . The purge gas panel  220  is configures to supply purge gas to the pre-clean chamber  204  and may include one or more purge gas sources and purge gas pumps. The process gas panel  218  is configured to supply process gas to the pre-clean chamber  204  and may include one or more process gas sources, a process gas pump, and/or valves. Each of the purge gas panel  220  and the process gas panel  218  may be accessed through a first door  221  and a second door  219  respectively. The first door  221  and the second door  219  are on an outer wall of the first pre-clean process module  106   a.    
     Each of the plurality of supports  210   a ,  210   b ,  210   c ,  212  are disposed between a top surface  224  of the gas panel  202  and a bottom surface  226  of the body  205  of the pre-clean chamber  204 . The plurality of supports  210   a ,  210   b ,  210   c ,  212  include a first support  210   a , a second support  210   b , a third support  210   c , and a removable fourth support  212 . Each of the first support  210   a , the second support  210   b , the third support  210   c , and the removable fourth support  212  are disposed at corners of the gas panel  202  and support the pre-clean chamber  204  and separate the pre-clean chamber  204  from the gas panel  202 . The removable fourth support  212  is configured be removed once the first pre-clean process module  106   a  is installed on the cluster tool assembly  100  by coupling the first pre-clean process module  106   a  to the transfer chamber  102 . Removing the removable fourth support  212  opens up the underside of the pre-clean chamber  204  and provides a maintenance passage. The second support  210   b  may include one or more branches for supporting a portion of the pedestal actuator  222  and/or an exhaust line  214 . Each of the supports  210   a ,  210   b ,  210   c ,  212  may alternatively be referred to as legs or spacers. 
     The hinge assembly  208  is configured to enable the lid  206  to be actuated with respect to the body  205  of the pre-clean chamber  204 . The lid  206  further includes a handle  216 . The handle  216  is located on a side of the lid  206  opposite the connection to the hinge assembly  208 . The handle  216  is located on the same side of the pre-clean chamber  204  as each of the manometer  116   a , the isolation port  118   a , and the throttle valve  120   a . Therefore, the lid  206  is configured to open away from the outward facing surface  115   a  and towards the transfer chamber  102 . Therefore, each of the manometer  116   a , the isolation port  118   a , the throttle valve  120   a , and the pre-clean chamber  204  may have maintenance performed thereon from the same side. 
     The manometer  116   a  is configured to measure the temperature within the pre-clean chamber  204 . In some embodiments, the manometer  116   a  measures more than one pressure within the pre-clean chamber  204 . The isolation port  118   a  is configured to control the exhaust rate within the pre-clean chamber  204  and may control the flow of exhaust from the pre-clean chamber  204  to an exhaust line  214 . The isolation port  118   a  may further be utilized to check the vacuum of the pre-clean chamber  204  and determine if a leak is present therein. 
     The throttle valve  120   a  is configured to control the flow of gas into the pre-clean chamber  204 . The throttle valve  120   a  may control one or both of the process gases or the purge gases. Process gases may include carrier gases or reactive gases, such as one or a combination of He, Ne, Ar, Kr, Xe, N 2 , H 2 , NH 3 , NF 3 , Cl 2 , HCl, HF, HBr, C 2 F 6 , CF 4 , C 3 F 8 , CHF 3 , CH 2 F 2 , C 4 F 8 , or SF 6 . The second pre-clean process module  106   b  is similar to the first pre-clean process module  106   a.    
       FIG.  3 A  illustrates a schematic front isometric view of a first pre-clean control module  112   a . The first pre-clean control module  112   a  and the second pre-clean control module  112   b  are similar. The first pre-clean control module  112   a  is configured to control the first pre-clean process module  106   a . The first pre-clean control module  112   a  includes one or more power sources  308 ,  310 , and a controller  306 . The controller  306  is configured to control the process operations of the pre-clean chamber  204 . 
     The controller  306  is configured to supply instructions to the pre-clean chamber  204  as well as the power sources  308 ,  310 . The controller  306  further receives input from sensors within the first pre-clean process module  106   a . For example, the controller  306  may be configured to control flow of various gases via the gas panel  202  and coordinate operation of the power sources  308 ,  310  to facilitate gas and plasma flow within the first pre-clean process module  106   a . The controller  306  may also be configured to control all aspects of heating within the pre-clean chamber  204  and actuation of the pedestal actuator  222 . 
     The controller  306  includes a programmable central processing unit (CPU) that is operable with a memory and a mass storage device, an input control unit, and a display unit (not shown), such as power supplies, clocks, cache, input/output (I/O) circuits, and the like, coupled to the various components of the pre-clean chamber  204  to facilitate control of substrate processing. The controller  306  also includes hardware or software for monitoring substrate processing through sensors in the pre-clean chamber  204 , including sensors monitoring flow, RF power, electric field and the like. Other sensors that measure system parameters such as substrate temperature, chamber atmosphere pressure and the like, may also provide information to the controller  306 . 
     To facilitate control of the pre-clean chamber  204  and associated plasma and electric field formation processes, the CPU may be one of any form of general purpose computer processor that can be used in an industrial setting, such as a programmable logic controller (PLC), for controlling various chambers and sub-processors. The memory is coupled to the CPU and the memory is non-transitory and may be one or more of readily available memory such as random access memory (RAM), read only memory (ROM), floppy disk drive, hard disk, or any other form of digital storage, local or remote. Support circuits are coupled to the CPU for supporting the processor in a conventional manner. The plasma and electric field formation and other processes are generally stored in the memory, typically as a software routine. The software routine may also be stored and/or executed by a second CPU that is remotely located from the hardware being controlled by the CPU. 
     The memory is in the form of computer-readable storage media that contains instructions, that when executed by the CPU, facilitates the operation of pre-clean chamber  204 . The instructions in the memory are in the form of a program product such as a program that implements the method of the present disclosure. The program code may conform to any one of a number of different programming languages. In one example, the disclosure may be implemented as a program product stored on computer-readable storage media for use with a computer system. The program(s) of the program product define functions of the embodiments (including the methods described herein). 
     In certain embodiments, the program(s) embody machine learning capabilities. Various data features include process parameters such as processing times, temperatures, pressures, voltages, polarities, powers, gas species, precursor flow rates, and the like. Relationships between the features are identified and defined to enable analysis by a machine learning algorithm to ingest data and adapt processes being performed by the pre-clean chamber  204 . The machine learning algorithms may employ supervised learning or unsupervised learning techniques. Examples of machine learning algorithms embodied by the program include, but are not limited to, linear regression, logistic regression, decision tree, state vector machine, neural network, naïve Bayes, k-nearest neighbors, K-Means, random forest, dimensionality reduction algorithms, and gradient boosting algorithms, among others. In one example, the machine learning algorithm is utilized to modulate RF power and precursor gas flow to form a plasma and then facilitate cleaning of substrates disposed within the pre-clean chamber  204 . 
     Illustrative computer-readable storage media include, but are not limited to: (i) non-writable storage media (e.g., read-only memory devices within a computer such as CD-ROM disks readable by a CD-ROM drive, flash memory, ROM chips or any type of solid-state non-volatile semiconductor memory) on which information is permanently stored; and (ii) writable storage media (e.g., floppy disks within a diskette drive or hard-disk drive or any type of solid-state random-access semiconductor memory) on which alterable information is stored. Such computer-readable storage media, when carrying computer-readable instructions that direct the functions of the methods described herein, are embodiments of the present disclosure. In some embodiments, the controller  306  is an etherCAT controller. 
     Each of the one or more power sources  308 ,  310  are one of an alternating current (AC) or a direct current (DC) power source. In some embodiments, the one or more power sources  308 ,  310  are two or more power sources  308 ,  310 . The one or more power sources  308 ,  310  includes a first power source  308  and a second power source  310 . The first power source  308  is a DC power supply and is configured to supply DC power to the first pre-clean process module  106   a . The second power source  310  is an AC power supply and is configured to supply AC power to the first pre-clean process module  106   a . The combined first power source  308  and the second power source  310  are utilized to supply power to various elements within the first pre-clean process module  106   a . The first power source  308  may supply power to one or more of the gas panel  202 , heaters (not shown) within the pre-clean chamber  204 , the pedestal actuator  222 , the manometer  116   a , the isolation port  118   a , or the throttle valve  120   a . In some embodiments, the first power source  308  supplies power to each of the gas panel  202 , the heaters within the pre-clean chamber  204 , the pedestal actuator  222 , the manometer  116   a , the isolation port  118   a , and the throttle valve  120   a . The second power source  310  is configured to supply power to one or more of the heaters (not shown) within the pre-clean chamber  204 , a remote plasma source (RPS)  422  ( FIG.  4   ), or sensors within the pre-clean chamber  204 . 
     Each of the first power source  306 , the second power source  310 , and the controller  306  are disposed within a casing  302 . The casing  302  is a tower configured to hold each of the first power source  306 , the second power source  310 , and the controller  306 . The casing  302  is a metal or metal alloy container and may include multiple compartments and/or shelves for holding different electrical components. In some embodiments, each of the first power source  306  and the controller  306  are disposed on an upper shelf  311 , while the second power source  310  is disposed on a lower shelf  313  below the upper shelf  311 . 
     Power cables  312 ,  314  lead from each of the first power source  306  and the second power source  310 . The power cables  312 ,  314  are configured to transfer power to components of the first pre-clean process module  106   a . The power cables  312 ,  314  pass from inside of the casing  302 , into a first cable conduit  114   a , and to the first pre-clean process module  106   a . One or more signal cables  315  extend from the controller  306  to the first pre-clean process module  106   a . The one or more signal cables  315  are configured to carry a signal from the controller  306  to the first pre-clean process module  106   a  and/or carry a signal from one or more components of the first pre-clean process module  106   a  to the controller  306 . The one or more signal cables  315  extend from the controller  306 , through the first cable conduit  114   a , and to the first pre-clean process module  106   a . The first cable conduit  114   a  serves to shield each of the power cables  312 ,  314  and the one or more signal cables  315  from each other. 
     The first cable conduit  114   a  includes an outer body  304 . The outer body  304  is a metal or a metal alloy and surrounds each of the power cables  312 ,  314  and the one or more signal cables  315 . The outer body  304  prevents cross-talk or interference from outside electrical lines or power sources, and in one example, may act as a Faraday shield. The outer body  304  therefore serves to shield each of the power cables  312 ,  314  and the one or more signal cables  315 . The outer body  304  further serves to protect each of the power cables  312 ,  314  and the one or more signal cables  315  from tampering or damage, and organizes the power cables  312 ,  314  and the one or more signal cables  315 . The outer body  304  is segmented, such that the outer body  304  may be curved or shaped. The outer body  304  includes at least a first portion  328  and a second portion  330 . The first portion  328  and the second portion  330  are connected at a joint  326 . The first portion  328  extends from an outer surface of the casing  302 . A distal end of the first portion  328  furthest from the casing  302  is connected to the second portion  330  at the joint  326 . Additional portions may also be utilized and connected at different joints. The direction of the walls of the outer body  304  between the first portion  328  and the second portion  330  are different, such that the second portion  330  extends in a different direction than the first portion  328 . 
     As shown in  FIG.  3 B , the casing  302  includes several passages  320 ,  322 ,  324  disposed therein. Each of the passages  320 ,  322 ,  324  are configured to hold one or more cables, such as the power cables  312 ,  314  and the one or more signal cables  315 . In embodiments described herein, a first passage  320  is configured to have the first power cable  312  disposed therethrough. A second passage  322  is configured to have the second power cable  314  disposed therethrough. A third passage  324  is configured to have the one or more signal cables  315  disposed therethrough. Each of the passages  320 ,  322 ,  324  are separated from each other by one or more walls  316 ,  318 . The first passage  320  is separated from the second passage  322  by the first wall  316 . The second passage  322  is separated from the third passage  324  by the second wall  318 . The walls  316 ,  318  are configured to shield electromagnetic fields of each of the cables  312 ,  314 ,  315  from one another. The walls  316  are formed of a metal or a metal alloy and prevent noise caused by the proximity of each of the cables  312 ,  314 ,  315 . 
     In some embodiments, the walls  316 ,  318 , and the outer body  304  are formed of a polymer, such as a plastic material. In embodiments wherein first cable conduit  114   a  is formed of a polymer, each of the cables  312 ,  314 ,  315  are separated by a larger linear distance than in embodiments wherein the cables are disposed within a metal or metal alloy first cable conduit  114   a.    
     The first cable conduit  114   a  has a length L of greater than about 400 mm, such as greater than about 45000 mm, such as greater than about 500 mm, such as about 500 mm to about 750 mm, such as about 550 mm to about 750 mm. The length L is the linear length and extends along a major axis of the first cable conduit  114   a . The major axis is in the direction in which the first passage  320 , the second passage  322 , and the third passage  324  extend. The length L of the first cable conduit  114   a  limits the distance between the first pre-clean control module  112   a  and the first pre-clean process module  106   a . The first cable conduit  114   a  and the second cable conduit  114   b  are similar. 
       FIG.  4    illustrates a schematic front isometric view of a pre-clean chamber  204  with an open lid  206 . The pre-clean chamber  204  includes a substrate support pedestal  424 , and a plate stack  414  configured to deliver a gas or a plasma to a process volume  418  between the plate stack  414  and the substrate support pedestal  424 . The substrate support pedestal  424  is actuated upwards and downwards within a process volume  418  by the pedestal actuator  222 . A substrate is configured to be disposed on the substrate support pedestal  424  and cleaned within the pre-clean chamber  204 . 
     The lid  206  is disposed in an open position, such that the lid  206  is actuated about the hinge assembly  208  away from the outward facing surface  115   a . The hinge assembly  208  includes a hinge  408  coupled between the body  205  of the pre-clean chamber  204  and the lid  206 . The hinge  408  acts as a swivel point or pivot point of the lid  206 , such that an axis of rotation of the lid  206  passes through the hinge  408 . The hinge assembly  208  further includes an extendable piston  404  coupled to the lid  206  at a first connection point  406  and coupled to the body  205  at a second connection point  402 . The extendable piston  404  may alternatively be a spring. The extendable piston  404  is configured to allow the lid  206  to be actuated around the hinge  408 , while preventing the lid  206  from passing a pre-determined angle while in an open position. This assists in preventing accidental damage to the lid  206  while the lid  206  is open for maintenance. 
     The lid  206  includes the plate stack  414  disposed therein as well as the RPS  422 . The RPS  422  is configured to deliver plasma to the plate stack  414  during processing. The plate stack  414  includes one or more showerheads, diffusers, and/or ion blocker plates. The plate stack  414  includes a plurality of openings formed through a bottom showerhead to allow gases and plasma within the plate stack  414  to enter the process volume  418 . The RPS  422  is configured to provide a plasma to the plate stack  414 , such as a cleaning plasma. In some embodiments, the RPS  422  is replaced with a suitable inductively coupled plasma system or a capacitive coupled plasma system. 
     The process volume  418  is formed using one or more sidewalls  416 , a bottom surface of the plate stack  414  and the substrate support pedestal  424 . A substrate transfer passage  420  is disposed through one of the sidewalls  416  of the process volume  418  and to an inner facing surface  428 . The substrate transfer passage  420  is configured to enable a substrate to pass therethrough, such that the substrate is passed from the process volume  418  to the transfer chamber  102  or from the transfer chamber  102  to the process volume  418 . The inner facing surface  428  is disposed on the opposite side of the body  205  from the outward facing surface  115   a.    
     Side surfaces  430  are disposed between the inner facing surface  428  and the outward facing surface  115   a . An extendable piston  404  may be coupled to each of the side surfaces  430 , such that a first extendable piston  404  extends from one side surface  430  to the lid  206  while a second extendable piston  404  extends from an opposite side surface  430  to the lid  206 . 
     The first isolation port  118   a  may further include an exhaust coupling  426 . The exhaust coupling  426  is configured to be attached to the exhaust line  214 , such that gas and/or plasma is exhausted from the process volume  418  through the exhaust coupling  426 . 
       FIG.  5 A  illustrates a schematic plan view of a part of the cluster tool assembly  100  and a maintenance passage  502 . The maintenance passage  502  is an open passage through a portion of the cluster tool assembly  100 . The maintenance passage  502  is disposed between at least a portion of the first and second pre-clean control modules  112   a ,  112   b , the front end FI  108 , the pre-clean process modules  106   a ,  106   b , the mainframe power supply  122 , the load lock chamber  110 , and the transfer chamber  102 . The maintenance passage  502  provides access to each of the pre-clean control modules  112   a ,  112   b , the pre-clean process modules  106   a ,  106   b , the mainframe power supply  122 , the load lock chamber  110 , and a portion of the transfer chamber  102 . In one example, the maintenance passage  502  provides access to a robot or carousel of the transfer chamber  102  from the underside of the transfer chamber  102 . 
     The maintenance passage  502  is therefore disposed between a portion of the pre-clean process modules  106   a ,  106   b  and the pre-clean control modules  112   a ,  112   b . The maintenance passage  502  is further disposed between a portion of the pre-clean control modules  112   a ,  112   b  and the front end FI  108 , such that a first entrance  504   a  to the maintenance passage  502  is disposed between the first pre-clean control module  112   a  and the front end FI  108 . A second entrance  504   b  to the maintenance passage  502  is disposed between the second pre-clean control module  112   b  and the front end FI  108 . A first width D 1  of the first entrance  504   a  and the second entrance  504   b  is greater than about 400 mm, such as greater than about 500 mm, such as about 500 mm to about 750 mm, such as about 500 mm to about 650 mm. The first width D 1  of the first entrance  504   a  is the smallest opening point between an outer surface of one of the pre-clean control modules  112   a ,  112   b  and the outer surface of the front end FI  108 , such that the first width D 1  is the smallest linear distance between one of the pre-clean control modules  112   a ,  112   b  and the front end FI  108 . 
     Portions of the maintenance passage  502  pass over each of the cable conduits  114   a ,  114   b , underneath each of the pre-clean process modules  106   a ,  106   b , over the mainframe power supply  122 , and over the load lock chamber  110 . The portion of the maintenance passage  502  disposed over the load lock chamber  110  provides access to the first wall of an outer perimeter of the transfer chamber  102 . A second width D 2  is the width of the maintenance passage  502  at a narrowest point within the maintenance passage  502 . The second width D 2  is disposed between a portion of one of the pre-clean process modules  106   a ,  106   b  and the front end FI  108 . The second width D 2  is a linear distance between a portion of one of the pre-clean process modules  106   a ,  106   b  and the front end FI  108 . The second width D 2  is greater than about 400 mm, such as greater than about 500 mm, such as about 500 mm to about 700 mm, such as about 500 mm to about 625 mm. 
       FIG.  5 B  illustrates a schematic front isometric view of the maintenance passage  502  between the first pre-clean process module  106   a  and the first pre-clean control module  112   a . Each of the pre-clean control modules  112   a ,  112   b  have a first height D 3  of greater than about 1000 mm, such as greater than about 1100 mm, such as about 1100 mm to about 1500 mm, such as about 1100 mm to about 1300 mm. The first height D 3  is a height in a z-direction from a floor of a fabrication facility to a top surface of the pre-clean control modules  112   a ,  112   b . The first height D 3  of the pre-clean control modules  112   a ,  112   b  reduce the ability to perform maintenance by reaching over the pre-clean control modules  112   a ,  112   b . The height of the front end FI  108  is a similar or greater height than the pre-clean control modules  112   a ,  112   b.    
     The gas panel  202  has a second height D 4 . The second height D 4  is about 250 mm to about 500 mm, such as about 300 mm to about 450 mm, such as about 300 mm to about 400 mm, such as about 350 mm to about 400 mm. The second height D 4  is a height in a z-direction from a floor of a fabrication facility to the top surface  224  of the gas panel  202 . The second height D 4  is configured to enable a technician or other personnel to access components disposed above the top surface  224  of the gas panel  202  as well as each of the purge gas panel  220  and the process gas panel  218 . 
     The mainframe power supply  122  has a third height D 5 . The third height D 5  is about 250 mm to about 500 mm, such as about 300 mm to about 450 mm, such as about 300 mm to about 400 mm, such as about 350 mm to about 400 mm. The third height D 5  is a height in a z-direction from a floor of a fabrication facility to a top surface of the mainframe power supply  122 . The third height D 5  enables a technician or other personnel to access the mainframe power supply  122 , while still having horizontal clearance to move through the maintenance passage  502 . 
     The maintenance passage  502  has a fourth height D 6 . The fourth height D 6  is about 400 mm to about 675 mm, such as about 450 mm to about 625 mm, such as about 475 mm to about 615 mm. The fourth height D 6  is a height in a z-direction from the top surface  224  of the gas panel  202  to the bottom surface  226  of the body  205  of the pre-clean chamber  204 . The fourth height D 6  is the height of the smallest openings through the maintenance passage  502 , such that there is a fourth height D 6  of clearance as an individual passes through the entirety of the maintenance passage  502 . 
     The fourth height D 6  and the second width D 2  form a vertical plane through the maintenance passage  502 . The vertical plane is a cross section of the smallest passage through the maintenance passage  502 , such that the vertical plane has an area of greater than about 250,000 mm 2 , such as greater than about 300,000 mm 2 . In some embodiments, the vertical plane has an area of about 250,000 mm 2  to about 325,000 mm 2 , such as about 300,000 mm 2  to about 325,000 mm 2 . 
     The area of the cross section through the maintenance passage  502  is large enough to allow a technician or other personnel to pass therethrough and perform maintenance on any of the pre-clean control modules  112   a ,  112   b , the pre-clean process modules  106   a ,  106   b , the mainframe power supply  122 , the load lock chamber  110 , and/or the transfer chamber  102 . The formation of a single maintenance passage  502  assists in reducing the overall footprint of the cluster tool assembly  100  and improves the ease of performing maintenance on the cluster tool assembly  100 . The separation of the pre-clean control modules  112   a ,  112   b  into separate towers from the pre-clean process modules  106   a ,  106   b  enables the space around the pre-clean process modules  106   a ,  106   b  to be unobstructed. The cable conduits  114   a ,  114   b  couple the pre-clean process modules  106   a ,  106   b  and the pre-clean control modules  112   a ,  112   b  and enable the separation of the pre-clean control modules  112   a ,  112   b  from the pre-clean process modules  106   a ,  106   b  while shielding power and signal cables therein from interference. 
     The gas panels  202  are disposed below each of the pre-clean process modules  106   a ,  106   b  and are accessible from the outward facing surfaces  115   a ,  115   b . Similarly, each of the manometers  116   a ,  116   b , the isolation ports  118   a ,  118   b , and the throttle valves  120   a ,  120   b  extend from the outward facing surfaces  115   a ,  115   b  of each pre-clean process modules  106   a ,  106   b  to enable improved access to each of the manometers  116   a ,  116   b , the isolation ports  118   a ,  118   b , and the throttle valves  120   a ,  120   b . Each of the doors of the gas panels  202 , manometers  116   a ,  116   b , the isolation ports  118   a ,  118   b , and the throttle valves  120   a ,  120   b  are each accessible from the same side and therefore enable reduced clearances on other sides of the pre-clean process modules  106   a ,  106   b.    
     While the foregoing is directed to embodiments of the present disclosure, other and further embodiments of the disclosure may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.