Doped or undoped silicon carbide deposition and remote hydrogen plasma exposure for gapfill

Abstract

A doped or undoped silicon carbide (SiCxOyNz) film can be deposited in one or more features of a substrate for gapfill. After a first thickness of the doped or undoped silicon carbide film is deposited in the one or more features, the doped or undoped silicon carbide film is exposed to a remote hydrogen plasma under conditions that cause a size of an opening near a top surface of each of the one or more features to increase, where the conditions can be controlled by controlling treatment time, treatment frequency, treatment power, and/or remote plasma gas composition. Operations of depositing additional thicknesses of silicon carbide film and performing a remote hydrogen plasma treatment are repeated to at least substantially fill the one or more features. Various time intervals between deposition and plasma treatment may be added to modulate gapfill performance.

What is claimed is: 
     
         1 . An apparatus ( 600 ) for depositing a silicon carbide gapfill material in one or more features of a substrate ( 630 ), the apparatus ( 600 ) comprising:
 a reaction chamber ( 610 ) including a pedestal ( 635 ) for supporting the substrate ( 630 );   a vessel ( 650 ) for providing a silicon-containing precursor through a first gas inlet ( 655 ) into the reaction chamber ( 610 ) towards the substrate ( 630 );   a remote plasma source ( 660 ) configured to generate radical species and deliver the radical species through a second gas inlet ( 665 ) into the reaction chamber ( 610 ) towards the substrate ( 630 ) so that the radical species reacts with the silicon-containing precursor to deposit a first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 630 ) or treats the first thickness of the silicon carbide gapfill material to increase a size of an opening near a top surface of each of the one or more features of the substrate ( 630 ); and   a controller ( 640 ) configured to control at least one of a flow rate of the silicon-containing precursor, a treatment frequency, a treatment time, a treatment power, or a gas composition of the radical species.   
     
     
         2 . The apparatus of  claim 1 , wherein the controller ( 640 ) is configured to cause the radical species to treat the first thickness of the silicon carbide gapfill material to densify and shrink the first thickness of the silicon carbide gapfill material. 
     
     
         3 . The apparatus of  claim 1 , wherein the pedestal ( 635 ) comprises one or more heating/cooling elements to control a temperature of the substrate ( 630 ). 
     
     
         4 . The apparatus of  claim 1 , wherein the first gas inlet ( 655 ) for providing the silicon-containing precursor is separate from and located downstream from the second gas inlet ( 665 ) for delivering the radical species. 
     
     
         5 . The apparatus of  claim 1 , wherein the remote plasma source ( 660 ) is a capacitively coupled plasma source. 
     
     
         6 . The apparatus of  claim 1 , wherein the remote plasma source ( 660 ) is an inductively coupled plasma source. 
     
     
         7 . The apparatus of  claim 1 , wherein the controller ( 640 ) is configured to operate the remote plasma source ( 660 ) at an RF frequency equal to or greater than about 13.56 MHz. 
     
     
         8 . The apparatus of  claim 1 , further comprising:
 a showerhead ( 620 ) configured to distribute the silicon-containing precursor into the reaction chamber ( 610 ) via the first gas inlet ( 655 ), wherein the substrate ( 630 ) is located beneath the showerhead ( 620 ).   
     
     
         9 . The apparatus of  claim 1 , wherein the second gas inlet ( 665 ) is positioned above the substrate ( 630 ), wherein a distance between the remote plasma source ( 660 ) and the reaction chamber ( 610 ) is configured to provide reaction conditions in an environment adjacent to the substrate ( 630 ) that is free or substantially free of ionized species. 
     
     
         10 . The apparatus of  claim 9 , wherein the distance between the remote plasma source ( 660 ) and the reaction chamber ( 610 ) is based on an aggressiveness of a plasma generated in the remote plasma source ( 660 ) and a density of gas in the plasma in the remote plasma source ( 660 ). 
     
     
         11 . The apparatus of  claim 1 , wherein the second gas inlet ( 665 ) introduces a co-reactant into the reaction chamber ( 610 ) so that the radical species reacts with the silicon-containing precursor and the co-reactant to deposit the first thickness of the silicon carbide gapfill material. 
     
     
         12 . The apparatus of  claim 11 , wherein the co-reactant is partially converted to plasma and flows along a flow path of the radical species. 
     
     
         13 . The apparatus of  claim 1 , wherein the first gas inlet ( 655 ) introduces a co-reactant into the reaction chamber ( 610 ) so that the radical species reacts with the silicon-containing precursor and the co-reactant to deposit the first thickness of the silicon carbide gapfill material. 
     
     
         14 . The apparatus of  claim 1 , wherein the controller ( 640 ) is configured with instructions to perform the following operations:
 deposit the first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 630 );   treat the first thickness of the silicon carbide gapfill material to increase the size of the opening near the top surface of each of the one or more features of the substrate ( 630 ); and   deposit a second thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 630 ).   
     
     
         15 . An apparatus ( 700 ) for depositing a silicon carbide gapfill material in one or more features of a substrate ( 712 ), the apparatus ( 700 ) comprising:
 a reaction chamber ( 704 ) including a pedestal ( 714 ) for supporting a substrate ( 712 );   a precursor supply source ( 740 ) for providing one or more silicon-containing precursors through a gas outlet ( 742 ) into the reaction chamber ( 704 );   a remote plasma source ( 702 ) for generating and sustaining a plasma in a plasma region ( 724 ), wherein the remote plasma source ( 702 ) is separated from the reaction chamber ( 704 ) by a multiport gas distributor ( 706 ), wherein the gas outlet ( 742 ) is located downstream from the multiport gas distributor ( 706 ), and wherein the multiport gas distributor ( 706 ) disperses and diffuses radicals of the plasma from the remote plasma source ( 702 ) into the reaction chamber ( 704 ) to react with the one or more silicon-containing precursors to deposit a first thickness of a silicon carbide gapfill material in the one or more features of the substrate ( 712 ) or to treat the first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 712 ); and   a controller ( 750 ) configured to control at least one of a treatment frequency, a treatment time, a treatment power, or a gas composition of the plasma.   
     
     
         16 . The apparatus of  claim 15 , wherein the reaction chamber ( 704 ) includes a chemical vapor deposition zone ( 708 ) in an environment adjacent to the substrate ( 712 ) and a relaxation zone ( 738 ) defining a region between the gas outlet ( 742 ) and the multiport gas distributor ( 706 ), wherein a geometry of the relaxation zone ( 738 ) is configured so that the radicals of the plasma transition from excited radicals to ground state radicals. 
     
     
         17 . The apparatus of  claim 15 , wherein the multiport gas distributor ( 706 ) comprises a plurality of gas ports ( 734 ) each having an axial length to diameter ratio of between about 3:1 and 10:1. 
     
     
         18 . The apparatus of  claim 15 , wherein the multiport gas distributor ( 706 ) comprises a plurality of gas ports ( 734 ) that are arranged as an array of regularly spaced apart through-holes extending through a plate. 
     
     
         19 . The apparatus of  claim 18 , wherein the plurality of gas ports ( 734 ) occupy between about 5% and about 20% of an exposed surface area of the multiport gas distributor ( 706 ). 
     
     
         20 . The apparatus of  claim 15 , wherein the multiport gas distributor ( 706 ) comprises one or both of an ion filter and a photon filter. 
     
     
         21 . The apparatus of  claim 15 , further comprising:
 an additional gas supply ( 728 ) fluidly coupled with the remote plasma source ( 702 ) for supplying one or more additional gases into the reaction chamber ( 704 ).   
     
     
         22 . The apparatus of  claim 15 , wherein the multiport gas distributor ( 706 ) disperses and diffuses radicals of the plasma into the reaction chamber ( 704 ) to treat the first thickness of the silicon carbide gapfill material to increase a size of an opening near a top surface of each of the one or more features of the substrate ( 712 ). 
     
     
         23 . The apparatus of  claim 15 , wherein the radicals of the plasma comprise hydrogen radicals. 
     
     
         24 . The apparatus of  claim 15 , further comprising:
 a coil ( 718 ) arranged around the remote plasma source ( 702 ) and electrically coupled to a plasma controller ( 722 ), wherein the plasma controller ( 722 ) is configured to generate the plasma via inductively coupled plasma generation.   
     
     
         25 . The apparatus of  claim 15 , wherein the controller ( 740 ) is configured with instructions for performing the following operations:
 deposit the first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 712 );   treat the first thickness of the silicon carbide gapfill material to increase a size of an opening near a top surface of each of the one or more features of the substrate ( 712 ); and   repeat operations of depositing and treating the silicon carbide gapfill material until the one or more features of the substrate ( 712 ) are filled or substantially filled with the silicon carbide gapfill material.   
     
     
         26 . An apparatus ( 700 ) for depositing a silicon carbide gapfill material in one or more features of a substrate ( 712 ), the apparatus ( 700 ) comprising:
 a reaction chamber ( 704 ) comprising supporting means ( 714 ) for supporting the substrate ( 712 );   remote plasma generating means ( 702 ) for generating remote plasma separate from the reaction chamber ( 704 ), wherein the remote plasma comprises reactant radicals;   precursor delivery means ( 742 ) for delivering a silicon-containing precursor into the reaction chamber ( 704 );   radicals introducing means ( 706 ) for introducing the reactant radicals into the reaction chamber ( 704 ) towards the substrate ( 712 ) under conditions to react with the silicon-containing precursor to deposit a first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 712 ); and   controlling means ( 750 ) for controlling operations in the reaction chamber ( 704 ) and the remote plasma generating means ( 702 ) to cause: generating remote hydrogen plasma in the remote plasma generating means ( 702 ) and exposing the substrate ( 712 ) to the remote hydrogen plasma to densify and shrink the first thickness of the silicon carbide gapfill material.   
     
     
         27 . The apparatus of  claim 26 , wherein the controlling means ( 750 ) further causes: filling or substantially filling the one or more features of the substrate ( 712 ) with the silicon carbide gapfill material. 
     
     
         28 . The apparatus of  claim 26 , wherein the silicon carbide gapfill material comprises a low-k dielectric material, wherein the low-k dielectric material has an effective dielectric constant of about 4.0 or lower. 
     
     
         29 . The apparatus of  claim 26 , wherein the remote plasma generating means ( 702 ) is configured to generate a capacitively coupled remote plasma comprising hydrogen radicals, wherein the radicals introducing means ( 706 ) is configured to introduce the hydrogen radicals into the reaction chamber ( 704 ) towards the substrate ( 712 ) under conditions in which the hydrogen radicals are in a ground state to react with the silicon-containing precursor to deposit the first thickness of the silicon carbide gapfill material.