Methods and apparatus for electrically and/or chemically-mechanically removing conductive material from a microelectronic substrate

Abstract

A method and apparatus for removing conductive material from a microelectronic substrate. In one embodiment, a support member supports a microelectronic substrate relative to a material removal medium, which can include first and second electrodes and a polishing pad. One or more electrolytes are disposed between the electrodes and the microelectronic substrate to electrically link the electrodes to the microelectronic substrate. The electrodes are then coupled to a source of varying current that electrically removes the conductive material from the substrate. The microelectronic substrate and/or the electrodes can be moved relative to each other to position the electrodes relative to a selected portion of the microelectronic substrate, and/or to polish the microelectronic substrate. The material removal medium can remove gas formed during the process from the microelectronic substrate and/or the electrodes. The medium can also have different first and second electrical characteristics to provide different levels of electrical coupling to different regions of the microelectronic substrate.

1 - 64 . (Canceled)  
     
     
         65 . An apparatus for removing conductive material from a microelectronic substrate, comprising: 
 a support member configured to support a microelectronic substrate; and    a material removal medium proximate to the support member, the material removal medium including a first electrode and a second electrode positioned to be spaced apart from the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current, the material removal medium further including a gas removal surface positioned to remove gas from a region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.    
     
     
         66 . The apparatus of  claim 65  wherein the microelectronic substrate has a face surface and an edge surface, and wherein the material removal medium includes a polishing surface disposed between the face surface and both the first and second electrodes during operation.  
     
     
         67 . The apparatus of  claim 65 , further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurized fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurized fluid during operation.  
     
     
         68 . The apparatus of  claim 65 , further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurizing fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurizing fluid during operation, at least a portion of the first surface of the polishing pad being spaced apart from the first electrode to define a fluid passage, the fluid passage having an entrance coupleable to a source of electrolytic fluid, the fluid passage further having an exit.  
     
     
         69 . The apparatus of  claim 68 , further comprising a vacuum source coupled to the exit of the fluid passage.  
     
     
         70 . The apparatus of  claim 65  wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate when the support member supports the microelectronic substrate.  
     
     
         71 . The apparatus of  claim 65  wherein the substrate support member is positioned to support the microelectronic substrate from below and the material removal medium is positioned above the substrate support.  
     
     
         72 . The apparatus of  claim 65  wherein at least one of the substrate support member and the material removal medium is rotatable at a rate sufficient to direct the gas radially outwardly and away from the microelectronic substrate.  
     
     
         73 . The apparatus of  claim 65 , further comprising the microelectronic substrate.  
     
     
         74 . The apparatus of  claim 65 , further comprising a liquid electrolyte disposed adjacent to the material removal medium.  
     
     
         75 . The apparatus of  claim 65  wherein the gas removal surface is one of a plurality of gas removal surfaces positioned to define a gas removal channel.  
     
     
         76 . The apparatus of  claim 65  wherein the material removal medium includes a medium support member supporting the first and second electrodes, and wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein the planarizing medium further includes a polishing pad positioned adjacent to at least one of the first and second electrodes and having the polishing surface facing downwardly and engaged with the microelectronic substrate during operation, the first and second electrodes being spaced apart from each other with the gas removal surface positioned above the microelectronic substrate during operation to collect the gas from the region proximate to the microelectronic substrate.  
     
     
         77 . The apparatus of  claim 65  wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein the gas removal surface is recessed into at least one of the downwardly facing surfaces.  
     
     
         78 . The apparatus of  claim 65  wherein the first and second electrodes each have a surface facing downwardly toward the microelectronic substrate during operation, and wherein at least one of the downwardly facing surfaces is non-horizontal to conduct gas away from the region proximate to the microelectronic substrate.  
     
     
         79 . The apparatus of  claim 65  wherein the material removal medium includes a porous polishing pad having a polishing surface with pores facing toward the microelectronic substrate during operation, and wherein the gas removal surface is in fluid communication with at least one of the pores to conduct gas away from the region.  
     
     
         80 . An apparatus for removing conductive material from a microelectronic substrate, comprising: 
 a support member configured to support a microelectronic substrate;    a material removal medium proximate to the support member, the material removal medium including a first electrode and a second electrode each positioned to be spaced apart from the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current; and    an ultrasonic energy emitter positioned proximate to the material removal medium to remove gas from a region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.    
     
     
         81 . The apparatus of  claim 80  wherein the ultrasonic energy emitter is positioned to contact an electrolytic fluid when the electrolytic fluid is disposed between the microelectronic substrate and at least one of the first and second electrodes.  
     
     
         82 . The apparatus of  claim 80  wherein the material removal medium further includes a gas removal surface positioned to remove the gas from the region proximate to the microelectronic substrate and/or at least one of the first and second electrodes during operation.  
     
     
         83 . The apparatus of  claim 80  wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate when the support member supports the microelectronic substrate.  
     
     
         84 . An apparatus for removing conductive material from a microelectronic substrate, comprising: 
 a substrate support member configured to support a microelectronic substrate;    a material removal medium proximate to the substrate support member and having a polishing surface positioned to engage the microelectronic substrate when the microelectronic substrate is supported by the substrate support member, at least one of the material removal medium and the substrate support member being movable relative to the other, the material removal medium further having a first electrode at least proximate to the polishing surface and a second electrode at least proximate to the polishing surface and spaced apart from the first electrode, at least one of the first and second electrodes being coupleable to a source of varying electrical current, at least one of the substrate support member and the planarizing medium having a gas removal surface positioned to receive and remove gas from a region proximate to the microelectronic substrate during operation.    
     
     
         85 . The apparatus of  claim 84  wherein the microelectronic substrate has a face surface and an edge surface, and wherein the material removal medium includes a polishing surface disposed between the face surface and both the first and second electrodes during operation.  
     
     
         86 . The apparatus of  claim 84 , further comprising the source of varying electrical current, and wherein the source coupled to at least one of the electrodes to transmit to the at least one electrode alternating current and/or pulsed direct current.  
     
     
         87 . The apparatus of  claim 84  wherein the substrate support is positioned to support the microelectronic substrate from below and the polishing surface is positioned to engage an upward facing surface of the microelectronic substrate.  
     
     
         88 . The apparatus of  claim 84 , further comprising the microelectronic substrate.  
     
     
         89 . The apparatus of  claim 84  wherein the polishing surface has pores facing toward the microelectronic substrate during operation, and wherein the gas removal surface is in fluid communication with at least one of the pores to conduct gas away from the region proximate to the microelectronic substrate.  
     
     
         90 . The apparatus of  claim 84 , further comprising a housing supporting the material removal medium, the housing being coupleable to a source of pressurizing fluid, and wherein the material removal medium includes a polishing pad having a first surface facing inwardly toward an interior of the housing and a second surface engaged with the microelectronic substrate during operation, the second surface being biased against the microelectronic substrate when the housing is coupled to the source of pressurizing fluid during operation, at least a portion of the first surface of the polishing pad being spaced apart from the first electrode to define a fluid passage, the fluid passage having an entrance coupleable to a source of electrolytic fluid and an exit, the fluid passage being positioned to entrain gas from at least one of first electrode and the first surface of the polishing pad.  
     
     
         91 . An apparatus for removing conductive material from a face surface of a microelectronic substrate, comprising: 
 a substrate support member configured to support a microelectronic substrate; and    a material removal medium positioned proximate to the substrate support member, the material removal medium having a medium support member and first and second electrodes supported by the medium support member, both the first and second electrodes facing toward the face surface of the microelectronic substrate during operation, the material removal medium further including a polishing pad at least proximate to the first and second electrodes and engaged with the microelectronic substrate when the substrate support member support the microelectronic substrate.    
     
     
         92 . The apparatus of  claim 91  wherein the polishing pad is interposed between at least a portion of the electrode surfaces and the microelectronic substrate during operation.  
     
     
         93 . The apparatus of  claim 91  wherein the polishing pad depends from at least one of the least electrodes.  
     
     
         94 . The apparatus of  claim 91  wherein the material removal medium further includes a gas removal surface positioned to receive and remove gas from a region proximate to the microelectronic substrate during operation.  
     
     
         95 . The apparatus of  claim 91  wherein the material removal medium has first and second regions positioned to be electrically coupled to the microelectronic substrate, the first region having a first electrical characteristic, the second region having a second electrical characteristic different than the first electrical characteristic.  
     
     
         96 . An apparatus for removing conductive material from a microelectronic substrate, comprising: 
 a support member configured to support a microelectronic substrate; and    a material removal medium proximate to the support member and having a polishing surface positioned to engage the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the material removal medium and the support member being movable relative to the other, the material removal medium having a first region with a first electrical characteristic and a second region with a second electrical characteristic different than the first electrical characteristic, the first region being aligned with a first portion of the microelectronic substrate and the second region being aligned with a second portion of the microelectronic substrate when the polishing surface is engaged with the microelectronic substrate, the material removal medium further including a first electrode proximate to the polishing surface and a second electrode proximate to the polishing surface, at least one of the first and second electrodes being coupleable to a source of varying electrical current.    
     
     
         97 . The apparatus of  claim 96  wherein the material removal medium includes a polishing pad having the polishing surface, further wherein the polishing pad has a first dielectric constant in the first region and a second dielectric constant in the second region, the first dielectric constant being different than the second dielectric constant.  
     
     
         98 . The apparatus of  claim 96  wherein the material removal medium includes a polishing pad having the polishing surface, the polishing pad being generally porous in the first region and generally non-porous in the second region.  
     
     
         99 . The apparatus of  claim 96  wherein the material removal medium includes a polishing pad having the polishing surface, the polishing pad having a first porosity in the first region and a second porosity different than the first porosity in the second region.  
     
     
         100 . The apparatus of  claim 96  wherein the material removal medium includes a generally porous polishing pad having the polishing surface, and wherein the material removal medium further includes a generally non-porous blocking material adjacent to the polishing pad in the first region to block pores of the polishing pad in the first region.  
     
     
         101 . An apparatus for removing conductive material from a microelectronic substrate, comprising: 
 a support member configured to support a microelectronic substrate; and    a material removal medium proximate to the support member and having a first region with a first electrical characteristic and a second region with a second electrical characteristic different than the first electrical characteristic, the first region being aligned with a first portion of the microelectronic substrate and the second region being aligned with a second portion of the microelectronic substrate when the support member supports the microelectronic substrate, the material removal medium further including a first electrode and a second electrode at least proximate to the microelectronic substrate when the microelectronic substrate is supported by the support member, at least one of the first and second electrodes being coupleable to a source of varying electrical current.    
     
     
         102 . The apparatus of  claim 101  wherein the material removal medium further includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation.  
     
     
         103 . The apparatus of  claim 101  wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, further wherein the polishing pad has a first dielectric constant in the first region and a second dielectric constant in the second region, the first dielectric constant being different than the second dielectric constant.  
     
     
         104 . The apparatus of  claim 101  wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, the polishing pad being generally porous in the first region and generally non-porous in the second region.  
     
     
         105 . The apparatus of  claim 101  wherein the material removal medium includes a polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, the polishing pad having a first porosity in the first region and a second porosity different than the first porosity in the second region.  
     
     
         106 . The apparatus of  claim 101  wherein the material removal medium includes a generally porous polishing pad having a polishing surface positioned to engage the microelectronic substrate during operation, and wherein the material removal medium further includes a generally non-porous blocking material adjacent to the polishing pad in the first region to block pores of the polishing pad in the first region.  
     
     
         107 . The apparatus of  claim 101  wherein the material removal medium includes a first electrolytic fluid in the first region and a second electrolytic fluid in the second region, the second electrolytic fluid being different than the first electrolytic fluid.