Patent Publication Number: US-2015064880-A1

Title: Post etch treatment technology for enhancing plasma-etched silicon surface stability in ambient

Description:
BACKGROUND OF THE INVENTION 
     1. Field 
     Embodiments of the present invention generally relate to a method and apparatus for post etch treatment technology of a substrate surface. More particularly, embodiments herein relate substrate surface passivation and improving substrate radical confinement after etching. 
     2. Description of Related Art 
     In the process of fabricating modern semiconductor integrated circuits (ICs), it is necessary to develop various material layers over previously formed layers and structures. Reliably producing submicron and smaller features is one of the key requirements of very large scale integration (VLSI) and ultra large scale integration (ULSI) of semiconductor devices. However, with the continued miniaturization of circuit technology, the dimensions of the size and pitch of circuit features, such as interconnects, have placed additional demands on processing capabilities. The multilevel interconnects that lie at the heart of this technology require precise imaging and placement of high aspect ratio features, such as vias and other interconnects. Reliable formation of these interconnects is critical to further increases in device and interconnect density. 
     As the circuit densities increase for next generation devices, the width or pitch of interconnects, such as vias, trenches, contacts, devices, gates and other features, as well as the dielectric materials there between, are decreasing from 45 nm to sub 20 nm dimensions. The smaller circuit densities require etch process parameters to be held to smaller tolerances and for contamination introduced into the etch process environment, as well as the surface of the substrate, to be minimized. Generally, a conventional hydrogen (H)-comprising post-etch treatment is used for making the semiconductor substrate surface stable in ambient conditions to prevent the off gassing of residual halogens which then contaminate the fabrication process. However, the conventional H-comprising post etch treatment do not provide enough surface treatment and induces condensed particles which accumulate on the semiconductor substrate surface during the ambient temperature wait time between processes. Defects are formed on the semiconductor substrate surface by the highly corrosive halogen by-products (condensed particles) which formed in the ambient conditions. Moreover, prolonged exposure from the highly corrosive halogens erodes a chamber process kits 
     Therefore, there is a need for an improved post etch treatment method and apparatus. 
     SUMMARY 
     Methods for performing post etch treatments on silicon surfaces etched using halogen chemistry are provided. The methods may be performed in-situ a chamber in which the silicon surfaces where etch, ex-situ the chamber, or in a hybrid process that combines both in-situ and ex-situ post etch treatment processes. 
     In one embodiment the post etch treatment process includes exposing a substrate having a silicon surface etched using halogen chemistry to a gas mixture comprising C x H y  and oxygen, wherein x and y are integers, forming a plasma from the gas mixture, binding halogen residues with species comprising the plasma to form non-volatile halogen containing elements, and pumping the non-volatile halogen containing elements from a chamber containing the substrate. 
     In one embodiment the post etch treatment process includes performing a first portion of the post etch treatment in a chamber in which the silicon surfaces were etched using halogen chemistry and performing a second portion of the post etch treatment in a chamber different from the chamber in which the silicon surfaces were etched. The first portion of the post etch treatment includes exposing the silicon surfaces etched using halogen chemistry to a gas mixture comprising C x H y  and oxygen, wherein x and y are integers, forming a plasma from the gas mixture, binding halogen residues with species comprising the plasma to form non-volatile halogen containing elements, and pumping the non-volatile halogen containing elements from the chamber containing the substrate. The second portion of the post etch treatment includes exposing the silicon surface to a gas mixture comprising C x H y  and oxygen, wherein x and y are integers, forming a plasma from the gas mixture, binding halogen residues with species comprising the plasma to form non-volatile halogen containing elements, and pumping the non-volatile halogen containing elements from the chamber containing the substrate. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited embodiments of the invention are obtained and can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to the embodiments thereof, which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of the invention, and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1  is a plan view of a semiconductor substrate processing system having an etch chamber and a load lock chamber; 
         FIG. 2  is a simplified cutaway view for the etch chamber of  FIG. 1 ; 
         FIG. 3  is a simplified cutaway view of the load lock chamber depicted in  FIG. 1 ; and 
         FIG. 4  is a block diagram of a method for a hybrid in-situ and ex-situ treatment of post etched substrates. 
     
    
    
     To facilitate understanding, identical reference numerals have been used, wherever possible, to designate identical elements that are common to the Figures. Additionally, elements of one embodiment may be advantageously adapted for utilization in other embodiments described herein. 
     DETAILED DESCRIPTION 
     Disclosed are embodiments for a post etch treatment (PET) of a substrate using hydrocarbon (CH)-containing gas chemistries. Prolonged hydrogen exposure of a substrate, in conventional hydrogen (H)-comprising PET processes, increases the erosion of process kits and particle generation on and around the substrate. Replacing the conventional H-comprising PET with CH-containing PET extends the process kit lifetime and better controls condensed particles. The CH comprising PET has shown better condensed particle control than conventional H-comprising PET over a prolong period of time. Tests have demonstrated that after 24 hours at ambient temperatures, the conventional H-comprising PET surfaces increasingly accumulates condensed particle while the CH-containing PET surfaces remain relatively stable with minimal accumulation of condensed particles. Additionally, CH-containing PET surfaces have lower halogen residue concentrations for F, Cl, and Br compared to the conventional H-comprising PET surfaces. It is believed that the conventional H-comprising PET allows unstable bonds at the surface to interact at the ambient temperatures. However, CH-containing PET formed a thin carbon passivation layer on the surface for the substrate, thereby preventing the reactions at the ambient temperatures. 
       FIG. 1  is a plan view of a semiconductor substrate processing system  100  having an etch chamber and a load lock chamber. The processing system  100  is suited for performing a CH-containing PET after an etch process. In one embodiment, the processing system  100  may be a suitably adapted CENTURA® integrated processing system, commercially available from Applied Materials, Inc., located in Santa Clara, Calif. It is contemplated that the CH-containing PET may be practiced in other processing systems, including those from other manufacturers. 
     The processing system  100  includes a vacuum-tight processing platform  104 , a factory interface  102 , and a system controller  144 . The processing platform  104  includes a plurality of processing chambers  110 ,  112 ,  132 ,  128 ,  120  and at least one load-lock chamber  142  that are coupled to a vacuum substrate transfer chamber  136 . Two load lock chambers  122 ,  142  are shown in  FIG. 1 . The factory interface  102  is coupled to the transfer chamber  136  by the load lock chambers  122 ,  142 . 
     In one embodiment, the factory interface  102  comprises at least one docking station  108  and at least one factory interface robot  114  to facilitate transfer of substrates. The docking station  108  is configured to accept one or more front opening unified pod (FOUP). Two FOUPS  106 A-B are shown in the embodiment of  FIG. 1 . The factory interface robot  114 , having a blade  116  disposed on one end of the factory interface robot  114 , is configured to transfer the substrate to and from the factory interface  102  to the load lock chambers  122 ,  142  of the processing platform  104 . 
     Each of the load lock chambers  122 ,  142  have a first port coupled to the factory interface  102  and a second port coupled to the transfer chamber  136 . The load lock chambers  122  are coupled to a pressure control system (not shown) which pumps down and vents the load lock chambers  122 ,  142  to facilitate passing the substrate between the vacuum environment of the transfer chamber  136  and the substantially ambient (e.g., atmospheric) environment of the factory interface  102 . 
     The transfer chamber  136  has a vacuum robot  130  disposed therein. The vacuum robot  130  has at least one blade  134  capable of transferring substrates  124  between the load lock chambers  122 ,  142  and the processing chambers  110 ,  112 ,  132 ,  128 ,  120 . 
     In one embodiment, at least one process chamber  110 ,  112 ,  132 ,  128 ,  120  is an etch chamber. For example, the process chamber  110  may be an AdvantEdge Mesa™ etch chamber available from Applied Materials, Inc. The processing chamber  110  may use a halogen-containing gas to etch the substrate  124  disposed therein. Examples of halogen-containing gas include hydrogen bromide (HBr), chlorine (Cl 2 ), carbon tetrafluoride (CF 4 ), and the like. 
     The system controller  144  is coupled to the processing system  100 . The system controller  144  controls the operation of the processing system  100  using a direct control of the processing chambers  110 ,  112 ,  132 ,  128 ,  120  of the processing system  100  or alternatively, by controlling the computers (or controllers) associated with the processing chambers  110 ,  112 ,  132 ,  128 ,  120  and the processing system  100 . In operation, the system controller  144  enables data collection and feedback from the respective chambers and system controller  144  to optimize performance of the processing system  100 . 
     The system controller  144  generally includes a central processing unit (CPU)  138 , a memory  140 , and support circuits  143 . The CPU  138  may be one of any form of a general purpose computer processor that can be used in an industrial setting. The support circuits  143  are conventionally coupled to the CPU  138  and may comprise cache, clock circuits, input/output subsystems, power supplies, and the like. The software routines when executed by the CPU  138 , transform the CPU  138  into a specific purpose computer (controller)  144 . The software routines may also be stored in and/or executed by a second controller (not shown) that is located remotely from the processing system  100 . 
     It has been known that prolonged hydrogen exposure may increase erosion of process kits and increase particle contamination of the substrate  124  and the processing system  100 . In one embodiment the substrate  124  is loading by the factory interface robot  114  into the load lock chamber  122  from the FOUP  106 B. A vacuum robot  130  moves the substrate  124  into the processing chamber  110  for etching. After etching, the substrate  124  is subject to a CH-containing post etch treatment. The CH-containing PET helps to extend the process kit lifetime and better control condensation of particles within the chamber  110 . In one embodiment, the CH-containing PET uses a C x H y  gas chemistry where x and y are integers. The CH-containing PET removes etchant and other particles from the surface of the etched substrate which may undesirably contaminate the environment of the processing system  100 . The CH-containing PET may be performed in-situ, for example in the processing chamber  110  in which the substrate was etched, or ex-situ the processing chamber  110 , for example in the load lock chamber  142  or transfer chamber  136 . Alternately, the CH-containing PET may be a hybrid operation wherein part of the operation takes place in-situ while another part of the hybrid operation is performed ex-situ the processing chamber  110 . 
     The CH-containing PET carried out in the same process chamber at the end of the plasma etch is herein after referred to as “in-situ PET.” The in-situ PET is performed after the etch process in the same chamber in where the substrate was etched. The CH-containing PET utilizes a plasma source gas comprising a C x H y  gas chemistry, wherein x and y are integers. The plasma source gas may also include oxygen and at least one noble gas or inert gas, such as argon (Ar) or helium (He). The in-situ PET reduces the overall process time for processing a substrate by eliminating the transfer of the substrate to another chamber for a PET process and any additional time for chamber pumping.  FIG. 2  illustrates an exemplary etch processing chamber  110  for performing in-situ PET. 
     The exemplary processing chamber  110  is configured as an etch processing chamber and is suitable for removing one or more material layers from a substrate and performing post etch treatment on a substrate  124 . One example of the process chamber that may be adapted to benefit from the invention is an AdvantEdge Mesa™ Etch processing chamber, available from Applied Materials, Inc., located in Santa Clara, Calif. It is contemplated that other etch chambers, including those from other manufactures, may be adapted to practice embodiments of the invention. 
     The processing chamber  110  includes a chamber body  205  having a processing volume defined therein. The chamber body  205  has sidewalls  212  and a bottom  218  and a ground shield assembly  226  coupled thereto. The sidewalls  212  have a liner  215  to protect the sidewalls  212  and extend the time between maintenance cycles of the processing chamber  110 . The dimensions of the chamber body  205  and related components of the processing chamber  110  are not limited and generally are proportionally larger than the size of the substrate  124  to be processed therein. Examples of substrate sizes include 200 mm diameter, 250 mm diameter, 300 mm diameter and 450 mm diameters, among others. 
     A chamber lid assembly  210  is mounted on the top of the chamber body  205 . The chamber body  205  may be fabricated from aluminum or other suitable materials. A substrate access port  213  is formed through the sidewall  212  of the chamber body  205 , facilitating the transfer of the substrate  124  into and out of the processing chamber  110 . The access port  213  may be coupled to a transfer chamber and/or other chambers of the substrate processing system  100  (as shown in  FIG. 1 ). 
     A pumping port  245  is formed through the sidewall  212  of the chamber body  205  and connected to the chamber volume through the exhaust manifold  223 . A pumping device (not shown) is coupled through the port  245  to the processing volume to evacuate and control the pressure therein. The pumping device may include one or more pumps and throttle valves. The pumping device and chamber cooling design enables high base vacuum (about 1×E −8  Torr or less) and low rate-of-rise (about 1,000 mTorr/min) at temperatures suited to thermal budget needs for etching and post etch treatment, e.g., about −25 degrees Celsius to about +500 degrees Celsius. 
     A gas source  260  is coupled to the chamber body  205  to supply process gases into the processing volume. In one or more embodiments, process gases includes at least one halogen containing gas, and may additionally include inert gases, non-reactive gases, and reactive gases if necessary. Examples of process gases that may be provided by the gas source  260  include, but not limited to, carbon tetrafluoride (CF 4 ), hydrogen bromide (HBr), hydrogen fluoride (HF), acetylene (C 2 H 4 ), methane (CH 4 ), argon gas (Ar), chlorine (Cl 2 ), nitrogen (N 2 ), oxygen gas (O 2 ), among others. Additionally, combinations of the gases may be supplied to the chamber body  205  from the gas source  260 . For instance, a mixture of HBr and O 2  may be supplied into the processing volume to etch an aluminum (Al) containing substrate. The gas source  260  may also provide process gasses for the in-situ PET. For example the process gas supplied by the gas source  260  for PET of the substrate  124  may include a mixture of H 2 , O 2  and N 2 ; O 2  and N 2 ; Ar and O 2 ; or CH 4  and O 2 , among others. In one embodiment, the gas source  260  provides CH 4  and O 2  into the chamber body  205  for PET of a substrate  124  to reduce halogen byproduct formation. 
     The lid assembly  210  may include a nozzle  214 . The nozzle  214  has one or more ports for introducing process gas from the gas source  260  into the processing volume. After the process gas is introduced into the processing chamber  110 , the gas is energized to form plasma. An antenna  248 , such as one or more inductor coils, may be provided adjacent to the processing chamber  110 . An antenna power supply  242  may power the antenna  248  through a match circuit  241  to inductively couple energy, such as RF energy, to the process gas to maintain a plasma formed from the process gas in the processing volume within the processing chamber  110 . Alternatively, or in addition to the antenna power supply  242 , process electrodes comprising a cathode below the substrate  124  and an anode above the substrate  124  may be used to capacitively couple RF power to the process gases to maintain the plasma within the processing volume. A controller may control the operation of the power supply  242  and also the operation of other components in the processing chamber  110 . 
     A substrate support pedestal  235  may include an electro-static chuck  222  for holding the substrate  124  during processing. The electro-static chuck (ESC)  222  uses the electro-static attraction to hold the substrate  124  to the substrate support pedestal  235  for an etching process. The ESC  222  is powered by an RF power supply  225  integrated with a match circuit  224 . The ESC  222  comprises an electrode  221  embedded within a dielectric body. The RF power supply  225  may provide a RF chucking voltage of about 200 volts to about 2000 volts to the electrode  221 . The RF power supply  225  may also include a system controller for controlling the operation of the electrode  221  by directing a DC current to the electrode  221  for chucking and de-chucking the substrate  124 . The ESC  222  has an isolator  228  for the purpose of making the sidewall of the ESC  222  less attractive to the plasma. Additionally, the substrate support pedestal  235  has a cathode liner  236  to protect the sidewalls of the substrate support pedestal  235  from the plasma gasses and to extend the time between maintenance of the plasma processing chamber  110 . The cathode liner  236  and the liner  215  may be formed from a ceramic material. For example, both the cathode liner  236  and liner  215  may be formed from Yttria. 
     The ESC  222  may include heaters  251 , disposed therein and connected to a power source  250 , for heating the substrate. The cooling base  229  may include conduits for circulating a heat transfer fluid to sinking heat from the ESC  222  and substrate  124  disposed thereon. The ESC  222  is configured to perform in the temperature range required by the thermal budget of the device being fabricated on the substrate  124 . For example, the ESC  222  may be configured to maintain the substrate  124  at a temperature of about minus about 25 degrees Celsius to about 500 degrees Celsius. The cooling base  229  is provided to protect the substrate support pedestal  235  and assists in controlling the temperature of the substrate  124 . For example, the temperature of the substrate  124  in the etch processing chamber  110  is about 70 degrees Celsius to about 88 degrees Celsius for the etch process and the PET process. To mitigate process drift and time, the temperature of the substrate  124  is maintained substantially constant throughout the time the substrate  124  is in the etch chamber. In one embodiment, the temperature of the substrate  124  is maintained throughout the etch process and the PET process at about 80 degrees Celsius. 
     A cover ring  230  is disposed on the ESC  222  and along the periphery of the substrate support pedestal  235 . The cover ring  230  is configured to confine etching gases to a desired portion of the exposed top surface of the substrate  124 , while shielding the top surface of the substrate support pedestal  235  from the plasma environment inside the processing chamber  200 . Lift pins (not shown) are selectively moved through the substrate support pedestal  235  to lift the substrate  124  above the substrate support pedestal  235  to facilitate access to the substrate  124  by a vacuum robot  130  (shown in  FIG. 1 ) or other suitable transfer mechanism. 
     A system controller  144  (shown in  FIG. 1 ) may be coupled to the processing chamber  110 . The system controller  144  may be utilized to control the process sequence, regulating the gas flows from the gas source  260  into the processing chamber  110  and other process parameters. Software routines, when executed by the CPU  138 , transform the CPU  138  into a specific purpose computer (controller) that controls the processing chamber  110  such that the processes are performed in accordance with the present invention. The software routines may also be stored in memory  140  and/or executed by a second controller (not shown) that is collocated with the processing chamber  110 . 
     The in-situ PET provides a high throughput for an integrated etch recipe and reduces the time between completing the etching process and the surface treatment for the substrate  124  by combining the steps in one chamber. In addition, “in-situ” PET may also be used as a de-chunking step. The in-situ PET enables a shorter in-situ chamber clean (ICC) time which enhances the throughput for the processing chamber  110  and prolongs the lifetime of the process kits. 
     The off gassing halogens from an etched surface of the substrate  124  may condensate to form particle contamination. The PET stabilizes the surface of the substrate  124  to abate the off gassing halogens and the particles formed by condensing of the gasses at ambient temperatures. The condensed particle (adders) counts are checked to determine the success of a PET recipe. In one embodiment, the particle adder count for a substrate  124  is less than about 10 adders after the post etch treated substrate  124  is held for about 24 hours in a closed FOUP. 
     The abatement for various etchants may have different PET recipe strategies. Example combinations for PET gasses may include hydrogen (H 2 ), oxygen (O 2 ) and nitrogen (N 2 ); O 2  and N 2 ; argon (Ar) and O 2 ; or methane (CH 4 ) and O 2 ; to name a few. Additionally, the recipe for the PET gasses may call for the gasses to be applied over a specified period of time, for example, about 10 seconds to about 30 seconds. The different gases used in the PET processes may be selected in response to the different enchants used in the etch processing chamber  110 . In one embodiment, halogen abatement may be performed in-situ with the combination of oxygen (O 2 ) and CH-containing PET. Meanwhile, chlorine (Cl) abatement may be performed in-situ with O 2  and CH-containing PET gasses, and additionally carried out over a long period of time, for example about 20 seconds. 
     In certain embodiments, after etching the surface of the substrate  124  in an etch processing chamber  110 , a post-etch treatment is performed in-situ, in the processing chamber  110 . The processing chamber  110  vacuum pressures may be maintained at about 20 mT and the bias power removed from the substrate  124  to prevent further etching of the surface of the substrate  124 . A process gas is introduced by the gas source  260 . 
     In one embodiment, the gas source  260  provides about 50 sccm of H 2 , about 200 sccm of O 2 , and about 50 sccm of N 2  into the processing chamber  110  to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna  248  to form plasma from the process gas mixture. For about 20 seconds, the reactive specifies from the plasma treats the surface of the substrate  124  and other surfaces within the processing chamber  110 . 
     In another embodiment, the gas source  260  provides about 5 sccm of CH 4 , and about 200 sccm of O 2  into the processing chamber  110  to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna  248  to form plasma from the process gas mixture. For about 20 seconds, the reactive specifies from the plasma treats the surface of the substrate  124  and other surfaces within the processing chamber  110 . 
     In yet another embodiment, the gas source  260  provides about 200 sccm of O 2 , and about 50 sccm of N 2  into the processing chamber  110  to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna  248  to form plasma from the process gas mixture. For about 20 seconds, the reactive specifies from the plasma treats the surface of the substrate  124  and other surfaces within the processing chamber  110 . 
     In yet another embodiment, the gas source  260  provides about 100 sccm of Ar and about 200 sccm of O 2  into the processing chamber  110  to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna  248  to form plasma from the process gas mixture. For about 20 seconds, the reactive specifies from the plasma treats the surface of the substrate  124  and other surfaces within the processing chamber  110 . 
     The process gas stabilizes the surface of the substrate  124  and reduces the off gassing of halogens from the surface of the substrate  124  and byproducts forming on the substrate or the surfaces of the processing chamber  110   
     Alternatively the PET may be carried out in a different processing chamber from which the substrate  124  was etched. The PET operation performed external to the processing chamber  110  in which the substrate  124  was etched is referred to as ex-situ PET. Ex-situ PET allows for the usage of a high pedestal temperature compared to the in-situ PET process which provides improved halogen abatement. In one embodiment, the ex-situ PET may be performed in a load lock chamber to remove volatile halogen residues from the surface of the substrate  124 . 
     Referring briefly back to  FIG. 1 , the factory interface  102  is coupled to the transfer chamber  136  by the load lock chambers  122 ,  142 . The vacuum robot  130  transfers the substrate  124  from the processing chamber  110  through the load lock chamber  142  to the factory interface  102 . The load lock chamber  142  has a chamber body  340  with openings  360  configured to allow the substrate  124  to enter and exit the load lock chamber  142 . 
       FIG. 3  depicts a simplified cutaway view for the load lock chamber  142  configured to perform ex-situ PET. The chamber body  340 , of the load lock  142  chamber, has a first chamber  342  and a second chamber  344  defined therein. The first chamber  342  is isolated from the second chamber  344  by a wall  320  such that the pressure within the chambers  342 ,  344  may be independently controlled. The first chamber  342 , shown in the embodiment depicted in  FIG. 3  stacked above the second chamber  344 , is configured to not only transfer substrates between the factory interface  102  and transfer chamber  136 , but also to perform a post etch treatment process. 
     In the embodiment depicted in  FIG. 3 , the first chamber  342  includes a heater  311  coupled to a power source  310 . The heater  311  is configured for heating a substrate support pedestal  346 . The substrate support pedestal  346  is disposed below a gas distribution plate  348 . A gas panel  350  is coupled to the first chamber  342  through a remote plasma source  352  such that reactive specifies from a processing gas may be provided into the first chamber  342  through the gas distribution plate  348  to process the substrate  124  disposed on the heated substrate support pedestal  346 . The gas panel  350  may also be configured to provide a purged gas. 
     A pumping port  368  is connected to the first chamber  342  and second chamber  344 . A slit valve door  364  opens and closes access through the openings  360 . A pumping device  370 , coupled to the volume of chambers  342 ,  344 , may evacuate and control the pressure in the load lock chamber  142  once the slit valve door  364  has been closed. The pumping device  370  may include one or more pumps and throttle valves. The pumping device  370  enables high base vacuum of about 1×E −8  Torr or less. 
     The first chamber  342  may be utilized to pass substrates from the transfer chamber  136  to the factory interface  102 , while the second chamber  344  may be solely utilized to have unprocessed substrates from the factory interface  102  into the transfer chamber  136 , thereby minimizing the potential of cross contamination between processed and unprocessed substrates. 
     As previously stated, one advantage of the halogen-containing residue removal process is the usage of the high temperature substrate support pedestal  346  for halogen abatement. During the ex-situ PET the substrate support pedestal  346  may raise the temperature of the processed substrate, thereby converting the halogen-containing residues to a non-volatile compound. In one embodiment, the substrate support pedestal  346  raises the surface temperature of the substrate  124  to about 250 degrees Celsius to convert the halogen-containing residues to a non-volatile compound. The remote plasma source  352  provides reactive species which bind, or react, with the non-volatile compounds and/or halogen containing residues. The non-volatile compounds are then pumped out from the first chamber  342  of the load lock chamber  142  to remove effectively the halogens from the substrate  124  and components of the chamber  342 . 
     The different gases used in the ex-situ PET processes may be selected in response to the different enchants used in the etch processing chamber  110 . Examples of ex-situ PET process gas mixtures may include oxygen (O 2 ) and nitrogen (N 2 ); Forming Gas (FG) and O 2 ; or O 2 , N 2  and water (H 2 O); among others. FG may be a mixture of hydrogen and nitrogen. In one embodiment, the FG is about 1% to about 3% diluted H 2  in N 2 . Additionally, the selection for the different ex-situ PET gasses may include the application of the process gasses over a specified period of time, for example, about 10 seconds to about 30 seconds. 
     Etch chambers may use a halogen-containing gas to etch the substrates therein. Examples of halogen-containing gas include hydrogen bromide (HBr), chlorine (Cl 2 ), carbon tetrafluoride (CF 4 ), and the like. Fluorine (F), chlorine (Cl), and bromine (Br) abatement may be performed ex-situ with the combination of oxygen (O 2 ) and nitrogen (N 2 ) containing gasses along with a high substrate  124  temperature of about 250 degrees Celsius. 
     In certain embodiments, at least one of the process chambers coupled to the transfer chamber  136  is an etch chamber. After etching the substrate, halogen-containing residues may be left on the substrate  124  surface. The vacuum robot moves the substrate  124  to the first chamber  342  of the load lock chamber  142 . The first chamber  342  performs ex-situ PET on the substrate  124 . The heater  311  in the first chamber  342  heats the substrate  124  to about 250 degrees Celsius, under a vacuum pressure of about 700 mT. 
     In one embodiment, the gas panel  350  provides 3500 sccm of O 2 , and 350 sccm of N 2  through the remote plasma source  352  to form a process gas mixture. About 5000 Watts of RF power is provided to the remote plasma source  352  to form plasma from the process gas mixture. The plasma reactive specifies may treat the surface of the substrate  124  for about 20 seconds. 
     In another embodiment, the gas panel  350  provides 2500 sccm of O 2 , 250 sccm of N 2 , and 500 sccm of H 2 O through the remote plasma source  352  to form a process gas mixture. About 5000 Watts of RF power is provided to the remote plasma source  352  to form plasma from the process gas mixture. The plasma reactive specifies may treat the surface of the substrate  124  for about 20 seconds. 
     In yet another embodiment, the gas panel  350  provides 2500 sccm of O 2  and 500 sccm of FG through the remote plasma source  352  to form a process gas mixture. About 5000 Watts of RF power is provided to the remote plasma source  352  to form plasma from the process gas mixture. The plasma reactive specifies may treat the surface of the substrate  124  for about 20 seconds. 
     Although the first chamber  342  of the load lock chamber  142  has been described as configured to perform an ex-situ PET process, it is contemplated that the method of performing a PET of the substrate  124  may be also be a hybrid method wherein the PET process may be performed both in-situ and ex-situ.  FIG. 4  illustrates a method  400  for a hybrid in-situ and ex-situ treatment of post etched substrates. Steps in the method provide in-situ and ex-situ recipes which compliment and work in relationship with each other. It should be noted that the combination of the in-situ PET and ex-situ PET in the hybrid PET may have results that contrast to than that of in-situ PET or ex-situ PET performed alone. 
     At block  410 , an in-situ PET is performed on a substrate. After completing an etching process, the substrate remains in the etch chamber for further processing. The etch chamber may be similar to processing chamber  110  as shown in  FIG. 2 . The in-situ PET process performed in the etch chamber is performed in consideration of further treatment ex-situ. 
     In one embodiment, after etching the surface of the substrate in the etch processing chamber, the first portion of the hybrid PET is performed in-situ. The processing chamber vacuum pressures may be maintained at about 20 mT and the bias power removed from the substrate to prevent further etching of the substrate surface. A process gas is introduced by the gas source. The gas source provides about 200 sccm of O 2 , and about 50 sccm of N 2  into the processing chamber to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna to form plasma from the process gas mixture. For about 20 seconds, the plasma reactive specifies may treat the substrate surface and additionally the process chamber. 
     In another embodiment, the in-situ portion of the hybrid PET is performed in the processing chamber with vacuum pressures of about 20 mT and the bias power turned off to prevent further etching of the substrate surface. The gas source provides about 5 sccm of CH 4 , and about 200 sccm of O 2  into the processing chamber to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna to form plasma from the process gas mixture. For about 20 seconds, the plasma may treat the substrate surface and the process chamber to effectively remove halogen contamination. 
     At block  420 , the substrate is transferred from the etch processing chamber to a second chamber. The vacuum robot may transfer the substrate from the etch processing chamber into the second chamber. The second chamber is configured to perform the second ex-situ PET portion of the hybrid PET. 
     At block  430 , the ex-situ PET is performed on the substrate in the second processing chamber. The second processing chamber may be a second etch chamber, a load lock chamber, or other chamber configured to perform the ex-situ PET process. In one embodiment, the second processing chamber is the load lock chamber  142 . In another embodiment, the second processing chamber is an etch chamber. The second ex-situ PET portion of the hybrid PET is complimentary to the in-situ PET portion of the hybrid PET already performed on the substrate. The process for the second ex-situ PET portion of the hybrid PET may differ from that of a “stand alone” ex-situ PET process, wherein the substrate has not already been treated in-situ. 
     In one embodiment, the second ex-situ PET portion of the hybrid PET process is performed at a vacuum pressure which may be about 700 mT while the substrate surface is heated to about 250 degrees Celsius. The gas source provides about 3500 sccm of O 2 , and about 350 sccm of N 2  into the processing chamber to form the process gas mixture. About 5000 Watts of RF power is provided to the antenna to form plasma from the process gas mixture. For about 20 seconds, the plasma reactive specifies and heat may treat the substrate surface to effectively remove halogen contamination. 
     At block  440 , the substrate is transferred from the second processing chamber and eventually returned to the front opening unified pod (FOUP). The FOUP may hold a number of treated substrates. It has been demonstrated that substrates which have been treated as described above have less than about 10 additional particles condensed thereon after 24 hours when returned to the FOUP. 
     In one embodiment the hybrid PET has been shown to reduce the condensed particle formation to less than about 5 particles per substrate over 24 hours. The in-situ PET is performed in the etch chamber under a vacuum pressure of about 20 mT with the bias power removed from the substrate to prevent further etching of the substrate surface. The gas source provides about 5 sccm of CH 4 , and about 200 sccm of O 2  into the processing chamber to form the process gas mixture. About 1000 Watts of RF power is provided to the antenna to form plasma from the process gas mixture. For about 20 seconds, the plasma reactive specifies may treat the substrate surface and the process chamber. The substrate is moved to a second chamber wherein the processing chamber vacuum pressure may be about 700 mT and the substrate surface is heated to about 250 degrees Celsius. A process gas is introduced by the gas source. The gas source provides about 3500 sccm of O 2 , and about 350 sccm of N 2  into the processing chamber to form the process gas mixture. About 5000 Watts of RF power is provided to the antenna to form plasma from the process gas mixture. For about 10 seconds, the plasma reactive specifies and heat may treat the substrate surface. 
     In-situ PET, ex-situ PET and a hybrid PET, each represents a significant advancement in the field of substrate surface passivation and improving substrate radical confinement after etching. Moreover, condensed particle counts, are significantly reduced compared to conventional post etch treatment processes. 
     While the foregoing is directed to embodiments of the present invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow: