Abstract:
An apparatus for processing a substrate is provided. A chamber wall forms a processing chamber cavity. A substrate support for supporting the substrate is within the processing chamber cavity. A gas inlet for providing gas into the processing chamber is above a surface of the substrate. A window for passing RF power into the processing chamber cavity comprises a ceramic or quartz window body and a coating of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride on a surface of the ceramic window body. A coil is outside of the processing chamber cavity, wherein the window is between the processing chamber cavity and the coil.

Description:
BACKGROUND 
       [0001]    The present disclosure relates to the manufacturing of semiconductor devices. More specifically, the disclosure relates to coating chamber surfaces used in manufacturing semiconductor devices. 
         [0002]    During semiconductor wafer processing, plasma processing chambers are used to process semiconductor devices. Coatings are used to protect and ensure successful performance of the chamber surfaces in manufacturing semiconductor devices. 
         [0003]    Descriptions and embodiments discussed in this background are not presumed to be prior art. Such descriptions are not an admission of prior art. 
       SUMMARY 
       [0004]    To achieve the foregoing and in accordance with the purpose of the present disclosure, an apparatus for processing a substrate is provided. A chamber wall forms a processing chamber cavity. A substrate support for supporting the substrate is within the processing chamber cavity. A gas inlet for providing gas into the processing chamber is above a surface of the substrate. A window for passing RF power into the processing chamber cavity comprises a ceramic or quartz window body and a coating of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride on a surface of the ceramic window body. A coil is outside of the processing chamber cavity, wherein the window is between the processing chamber cavity and the coil. 
         [0005]    In another manifestation, an apparatus for plasma processing a substrate is provided. A chamber wall forms a processing chamber cavity. A substrate support for supporting the substrate is within the processing chamber cavity. A gas inlet for provides a gas into the processing chamber cavity. At least one plasma electrode is provided for transforming a gas within the processing chamber cavity into a plasma. A coating comprising at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride is on a surface within the processing chamber cavity, wherein the coating is 1 to 50 microns thick. 
         [0006]    In another manifestation of the disclosure an apparatus for use in a plasma etch chamber is provided. The apparatus comprises a ceramic, stainless steel, or quartz body and a coating comprising at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride covering a surface of the ceramic body, wherein the coating is 1 to 50 microns thick. 
         [0007]    These and other features of the present disclosure will be described in more detail below in the detailed description of the disclosure and in conjunction with the following figures. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0008]    The present disclosure is illustrated by way of example, and not by way of limitation, in the figures of the accompanying drawings and in which like reference numerals refer to similar elements and in which: 
           [0009]      FIG. 1  is a schematic view of an etch reactor that may be used in an embodiment. 
           [0010]      FIG. 2  is an enlarged cross-sectional view of part of a liner. 
           [0011]      FIG. 3  is an enlarged cross-sectional view of an electrostatic chuck which forms a lower electrode. 
           [0012]      FIG. 4  schematically illustrates an example of another plasma processing chamber. 
           [0013]      FIG. 5  is an enlarged cross-sectional view of a power window. 
           [0014]      FIG. 6  is an enlarged cross-sectional view of the gas injector. 
           [0015]      FIG. 7  is an enlarged cross-sectional view of part of a edge ring. 
           [0016]      FIG. 8  is an enlarged cross-sectional view of part of a pinnacle. 
       
    
    
     DETAILED DESCRIPTION OF THE EMBODIMENTS 
       [0017]    The present disclosure will now be described in detail with reference to a few embodiments thereof as illustrated in the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present disclosure. It will be apparent, however, to one skilled in the art, that the present disclosure may be practiced without some or all of these specific details. In other instances, well known process steps and/or structures have not been described in detail in order to not unnecessarily obscure the present disclosure. 
         [0018]    To facilitate understanding,  FIG. 1  is a schematic view of a plasma processing chamber  100  in which a substrate  166  has been mounted. The plasma processing chamber  100  comprises confinement rings  102 , an upper electrode  104 , a lower electrode  108 , a gas source  110 , a liner  162 , and an exhaust pump  120 . The liner  162  is formed from the substrate with the remelted ceramic layer. Within plasma processing chamber  100 , the wafer  166  is positioned upon the lower electrode  108 . The lower electrode  108  incorporates a suitable substrate chucking mechanism (e.g., electrostatic, mechanical clamping, or the like) for holding the wafer  166 . The reactor top  128  incorporates the upper electrode  104  disposed immediately opposite the lower electrode  108 . The upper electrode  104 , lower electrode  108 , and confinement rings  102  define the confined plasma volume  140 . 
         [0019]    Gas is supplied to the confined plasma volume  140  through a gas inlet  143  by the gas source  110  and is exhausted from the confined plasma volume  140  through the confinement rings  102  and an exhaust port by the exhaust pump  120 . Besides helping to exhaust the gas, the exhaust pump  120  helps to regulate pressure. A RF source  148  is electrically connected to the lower electrode  108 . 
         [0020]    Chamber walls  152  surround the liner  162 , confinement rings  102 , the upper electrode  104 , and the lower electrode  108 . The liner  162  helps prevent gas or plasma that passes through the confinement rings  102  from contacting the chamber walls  152 . Different combinations of connecting RF power to the electrode are possible. In an embodiment, the 27 MHz, 60 MHz and 2 MHz power sources make up the RF power source  148  connected to the lower electrode  108 , and the upper electrode  104  is grounded. A controller  135  is controllably connected to the RF source  148 , exhaust pump  120 , and the gas source  110 . The process chamber  100  may be a CCP (capacitive coupled plasma) reactor or an ICP (inductive coupled plasma) reactor or other sources like surface wave, microwave, or electron cyclotron resonance ECR may be used. 
         [0021]      FIG. 2  is an enlarged cross-sectional view of part of the liner  162 . The liner  162  comprises a liner body  204  and a coating  208  covering at least one surface of the liner body  204 . The liner body  204  may be of one or more different materials. Preferably, the liner body  204  is ceramic, quartz, or stainless steel. More preferably, the liner body  204  comprises at least one of stainless steel, silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). Preferably, the liner body  204  is aluminum oxide. The coating  208  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the liner body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). More preferably, the coating is formed by PECVD or PVD. 
         [0022]      FIG. 3  is an enlarged cross-sectional view of the electrostatic chuck which forms the lower electrode  108 . The lower electrode  108  comprises a lower electrode body  304  and a coating  308  covering at least one surface of the lower electrode body  304 . In this example, the coating  308  is only on the side surface of the lower electrode body  304 . The lower body  304  may be of one or more different materials. Preferably, the lower electrode body  304  is ceramic, quartz, or stainless steel. More preferably, the lower electrode body  304  comprises at least one of stainless steel, silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). The coating  308  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the electrode body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). 
         [0023]      FIG. 4  schematically illustrates an example of another plasma processing chamber  400  which may be used in another embodiment. The plasma processing chamber  400  includes a plasma reactor  402  having a plasma processing confinement chamber  404  therein. A plasma power supply  406 , tuned by a match network  408 , supplies power to a TCP coil  410  located near a power window  412  to create a plasma  414  in the plasma processing confinement chamber  404  by providing an inductively coupled power. A pinnacle  472  extends from the chamber wall  476  of the confinement chamber  404  to the window  412  forming a pinnacle ring. The pinnacle  472  is angled with respect to the chamber wall  476  and the window  412 , such that the interior angle between the pinnacle  472  and the chamber wall  476  and the interior angle between the pinnacle  472  and the window  412  are each greater than 90° and less than 180°. The pinnacle  472  provides an angled ring near the top of the confinement chamber  404 , as shown. The TCP coil (upper power source)  410  may be configured to produce a uniform diffusion profile within the plasma processing confinement chamber  404 . For example, the TCP coil  410  may be configured to generate a toroidal power distribution in the plasma  414 . The power window  412  is provided to separate the TCP coil  410  from the plasma processing confinement chamber  404  while allowing energy to pass from the TCP coil  410  to the plasma processing confinement chamber  404 . A wafer bias voltage power supply  416  tuned by a match network  418  provides power to an electrode  420  to set the bias voltage on the substrate  466  which is supported by the electrode  420 . A controller  424  sets points for the plasma power supply  406 , gas source/gas supply mechanism  430 , and the wafer bias voltage power supply  416 . 
         [0024]    The plasma power supply  406  and the wafer bias voltage power supply  416  may be configured to operate at specific radio frequencies such as, for example, 13.56 MHz, 27 MHz, 2 MHz, 60 MHz, 400 kHz, 2.54 GHz, or combinations thereof. Plasma power supply  406  and wafer bias voltage power supply  416  may be appropriately sized to supply a range of powers in order to achieve desired process performance. For example, in one embodiment, the plasma power supply  406  may supply the power in a range of 50 to 5000 Watts, and the wafer bias voltage power supply  416  may supply a bias voltage of in a range of 20 to 2000 V. In addition, the TCP coil  410  and/or the electrode  420  may be comprised of two or more sub-coils or sub-electrodes, which may be powered by a single power supply or powered by multiple power supplies. 
         [0025]    As shown in  FIG. 4 , the plasma processing chamber  308  further includes a gas source/gas supply mechanism  430 . The gas source  430  is in fluid connection with plasma processing confinement chamber  404  through a gas inlet, such as a gas injector  440 . The gas injector  440  may be located in any advantageous location in the plasma processing confinement chamber  404 , and may take any form for injecting gas. Preferably, however, the gas inlet may be configured to produce a “tunable” gas injection profile, which allows independent adjustment of the respective flow of the gases to multiple zones in the plasma process confinement chamber  404 . More preferably, the gas injector is mounted to the power window  412 , which means the gas injector may be mounted on, mounted in, or form part of the power window. The process gases and byproducts are removed from the plasma process confinement chamber  404  via a pressure control valve  442  and a pump  444 , which also serve to maintain a particular pressure within the plasma processing confinement chamber  404 . The pressure control valve  442  can maintain a pressure of less than 1 ton during processing. An edge ring  460  is placed around the substrate  466 . The gas source/gas supply mechanism  430  is controlled by the controller  424 . A Kiyo by Lam Research Corp. of Fremont, Calif., may be used to practice an embodiment. 
         [0026]      FIG. 5  is an enlarged cross-sectional view of the power window  412 . The power window  412  comprises a window body  504  and a coating  508  covering at least one surface of the window body  504 . In this example, the coating  508  is only on one surface of the window body  504 . The window body  504  may be of one or more different materials. Preferably, the window body  504  is ceramic or quartz. More preferably, the window body  504  comprises at least one of silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). Most preferably, the window body  504  comprises AlO or quartz. The coating  508  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the window body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). Preferably, the coating  508  is only on the side of the window body  504  facing the plasma as shown. 
         [0027]      FIG. 6  is an enlarged cross-sectional view of the gas injector  440 . The gas injector  440  comprises an injector body  604  and a coating  608  covering at least one surface of the injector body  604 . In this example, the coating  608  is only on at least two surfaces of the injector body  604 . The injector body  604  has a bore hole  612 , through which the gas flows. In some embodiments, the coating  608  may line the bore hole  612 . The gas injector  440  may also have a mount  616  for fixing the gas injector  440  to the power window  412 . The injector body  604  may be of one or more different materials. Preferably, the injector body  604  is ceramic or quartz. More preferably, the injector body  604  comprises at least one of silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). Most preferably, the injector body  604  comprises quartz or silicon oxide. The coating  608  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the injector body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). 
         [0028]      FIG. 7  is an enlarged cross-sectional view of part of the edge ring  460 . The edge ring  460  comprises a ring body  704  and a coating  708  covering at least one surface of the ring body  704 . Preferably, the ring body  704  is ceramic, stainless steel, or quartz. More preferably, the lower electrode body  304  comprises at least one of stainless steel, silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). The coating  708  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the electrode body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). 
         [0029]      FIG. 8  is an enlarged cross-sectional view of part of the pinnacle  472 . The pinnacle comprises a pinnacle body  804  and a coating  808  covering at least one surface of the pinnacle body  804 , which will face into the chamber to be exposed to plasma. Preferably, the pinnacle body  804  is ceramic, stainless steel, or quartz. More preferably, pinnacle body  804  comprises at least one of stainless steel, silicon (Si), quartz, silicon carbide (SiC), silicon nitride (SiN), aluminum oxide (AlO), aluminum nitride (AlC), or aluminum carbide (AlC). The coating  808  comprises at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Therefore, the coating may be a one or more in combination of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride and may also have other materials. Such other materials may be impurities which are difficult to remove in obtaining erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride or may be binding agents to allow the binding of the coating to the electrode body. More preferably, the coating is &gt;60% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Most preferably, the coating is &gt;99% pure by weight of at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride. Preferably, the coating is 1-50 μ thick. More preferably, the coating is 5-20 μ thick. Most preferably, the coating is 8-15 μ thick. To provide such a uniform and thin coating, preferably the coating is formed by at least one of plasma-enhanced chemical vapor deposition (PECVD), physical vapor deposition (PVD), chemical vapor deposition (CVD), atomic layer deposition (ALD), or aerosol deposition (ASD). 
         [0030]    It has been unexpectedly found that coatings comprising at least one of erbium oxide, erbium fluoride, samarium oxide, samarium fluoride, thulium oxide thulium fluoride, gadolinium oxide, or gadolinium fluoride are highly etch resistant. It has been found that PVD, CVD, ALD, or ASD may provide a thin but uniform layer that is highly etch resistant. Such a thin layer is easy to apply without significantly changing the dimensions of the object. 
         [0031]    In inductively coupled plasma reactors, one of the highest erosion mechanisms of parts is due to ion sputtering. Most sputtering is done by high energy ions, which bombard the power window  412 , pinnacle  472 , and gas injector  440  according to the geometry of the chamber. These high energy ions are energized through a RF field attacking the powered ends (coil and ESC) of the chamber. Hence these parts need extra protection. This is illustrated in  FIG. 4  showing various positive ions  415  colliding with the pinnacle  472 , power window  412 , or gas injector  440 . 
         [0032]    In other embodiments, other components such as the confinement rings  102 , chamber walls  152 , or upper electrode  104  may also have an etch resistant coating. 
         [0033]    While this disclosure has been described in terms of several embodiments, there are alterations, permutations, modifications, and various substitute equivalents, which fall within the scope of this disclosure. It should also be noted that there are many alternative ways of implementing the methods and apparatuses of the present disclosure. It is therefore intended that the following appended claims be interpreted as including all such alterations, permutations, and various substitute equivalents as fall within the true spirit and scope of the present disclosure.