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 ( 700 ) for depositing a doped or undoped silicon carbide (SiC x O y N z ) film in one or more features of a substrate ( 712 ), the apparatus ( 700 ) comprising:
 a reaction chamber ( 704 ) including a substrate support ( 714 ) for supporting the substrate ( 712 );   a precursor supply source ( 740 ) configured to supply a silicon-containing precursor through a gas outlet ( 742 ) into the reaction chamber ( 704 ) and deposit a first thickness of the SiC x O y N z  film in the one or more features of the substrate ( 712 ), wherein x has a value greater than zero, y has a value equal to or greater than zero, and z has a value equal to or greater than zero; and   a remote plasma source ( 702 ) separate from and upstream of the reaction chamber ( 704 ), wherein the remote plasma source ( 702 ) is configured to generate a remote hydrogen plasma and deliver the remote hydrogen plasma through a multiport gas distributor ( 706 ) into the reaction chamber ( 704 ) and expose the first thickness of the SiC x O y N z  film to the remote hydrogen plasma under conditions that increase a size of an opening near a top surface of each of the one or more features, wherein the precursor supply source ( 740 ) is further configured to supply the silicon-containing precursor through the gas outlet ( 742 ) to deposit a second thickness of the SiC x O y N z  film after exposing the first thickness of the SiC x O y N z  film to the remote hydrogen plasma.   
     
     
         2 . The apparatus of  claim 1 , further comprising:
 a controller ( 750 ) configured with instructions to control the remote plasma source ( 702 ), a flow of the silicon-containing precursor, and a delivery of the remote hydrogen plasma, wherein the controller ( 750 ) is configured to repeat operations of exposing the SiC x O y N z  film to the remote hydrogen plasma and depositing the SiC x O y N z  film in the one or more features until the one or more features are filled or substantially filled.   
     
     
         3 . The apparatus of  claim 1 , further comprising:
 a controller ( 750 ) configured with instructions to control conditions of the remote hydrogen plasma generated in the remote plasma source ( 702 ) including at least one of a treatment time, a treatment frequency, a treatment power, or a remote plasma gas composition, wherein at least one of the treatment time, the treatment frequency, the treatment power, or the remote plasma gas composition are controlled so that the size of the opening near the top surface of each of the one or more features is increased relative to a size of an opening near a bottom surface of each of the one or more features.   
     
     
         4 . The apparatus of  claim 3 , wherein the controller ( 750 ) is configured with instructions to expose the first thickness of the SiC x O y N z  film to the remote hydrogen plasma with the treatment time being between about 0.5 seconds and about 120 seconds. 
     
     
         5 . The apparatus of  claim 3 , wherein the controller ( 750 ) is configured with instructions to expose the first thickness of the SiC x O y N z  film to the remote hydrogen plasma with the treatment frequency being 10 Å or less of the SiC x O y N z  film per cycle of depositing the SiC x O y N z  film and exposing the SiC x O y N z  film to remote hydrogen plasma. 
     
     
         6 . The apparatus of  claim 3 , wherein the controller ( 750 ) is configured with instructions to expose the first thickness of the SiC x O y N z  film to the remote hydrogen plasma having a concentration between about 10% and about 50% by volume of hydrogen. 
     
     
         7 . The apparatus of  claim 1 , wherein each of the first thickness and the second thickness of the SiC x O y N z  film is equal to or less than about 10 Å. 
     
     
         8 . The apparatus of  claim 1 , further comprising:
 a controller ( 750 ) configured with instructions to introduce a time interval between depositing the first thickness of the SiC x O y N z  film and exposing the SiC x O y N z  film to the remote hydrogen plasma to modulate gapfill performance.   
     
     
         9 . The apparatus of  claim 1 , further comprising:
 a controller ( 750 ) configured with instructions to introduce a time interval after exposing the SiC x O y N z  film to the remote hydrogen plasma to modulate gapfill performance.   
     
     
         10 . An apparatus ( 700 ) for depositing a low-k gapfill material in one or more features of a substrate ( 712 ), the apparatus ( 700 ) comprising:
 a reaction chamber ( 704 ) including a substrate support ( 714 ) for supporting the substrate ( 712 );   a precursor supply source ( 740 ) configured to supply a deposition precursor through a gas outlet ( 742 ) into the reaction chamber ( 704 );   a remote plasma source ( 702 ) separate from and upstream of the reaction chamber ( 704 ), wherein the remote plasma source ( 702 ) is configured to generate reactant radicals and introduce the reactant radicals through a showerhead ( 706 ) into the reaction chamber ( 704 ) towards the substrate ( 712 ), wherein the reactant radicals react with the deposition precursor to deposit a first thickness of the low-k gapfill material in the one or more features of the substrate ( 712 ); and   a controller ( 750 ) configured with instructions for performing the following operations:
 (a) deposit the first thickness of the low-k gapfill material in the one or more features of the substrate ( 712 ); 
 (b) expose the low-k gapfill material to remote hydrogen plasma to treat the low-k gapfill material; and 
 (c) repeat operations (a) and (b) until the one or more features of the substrate ( 712 ) are filled or substantially filled with the low-k gapfill material. 
   
     
     
         11 . The apparatus of  claim 10 , wherein the controller ( 750 ) is configured with instructions for depositing the first thickness of the low-k gapfill material conformally in the one or more features of the substrate ( 712 ), wherein the first thickness of the low-k gapfill material has a conformality of at least 80%. 
     
     
         12 . The apparatus of  claim 10 , further comprising:
 a source gas supply ( 726 ) fluidly coupled to the remote plasma source ( 702 ) and configured to supply a source gas to the remote plasma source ( 702 ), wherein the source gas comprises a mixture of hydrogen gas and an inert gas, and wherein a concentration of the source gas is at least 25% by volume of hydrogen gas.   
     
     
         13 . The apparatus of  claim 10 , further comprising:
 an additional gas supply ( 728 ) fluidly coupled with the remote plasma source ( 702 ) configured to supply a co-reactant to the remote plasma source ( 702 ), wherein the remote plasma source ( 702 ) is configured to introduce the co-reactant into the reaction chamber ( 704 ), and wherein the reactant radicals react with the co-reactant and the deposition precursor to deposit the first thickness of the low-k gapfill material.   
     
     
         14 . The apparatus of  claim 13 , wherein the controller ( 750 ) is configured to tune a composition of the low-k gapfill material by the co-reactant. 
     
     
         15 . The apparatus of  claim 10 , wherein the low-k gapfill material comprises doped or undoped silicon carbide, wherein an atomic concentration of carbon in the first thickness of the low-k gapfill material is between about 10% and about 40%. 
     
     
         16 . The apparatus of  claim 10 , wherein the controller ( 750 ) configured with instructions for exposing the low-k gapfill material to remote hydrogen plasma is configured with instructions for increasing a size of an opening near a top surface of each of the one or more features relative to a bottom surface of each of the one or more features during exposure to the remote hydrogen plasma. 
     
     
         17 . The apparatus of  claim 10 , wherein the controller ( 750 ) configured with instructions for exposing the low-k gapfill material to remote hydrogen plasma is configured with instructions for densifying and shrinking the first thickness of the low-k gapfill material during exposure to the remote hydrogen plasma. 
     
     
         18 . The apparatus of  claim 10 , wherein the controller ( 750 ) configured with instructions for exposing the low-k gapfill material to remote hydrogen plasma is configured with instructions for exposing the low-k gapfill material isotropically with hydrogen radicals so that treating the low-k gapfill material occurs preferentially at a top opening of the one or more features relative to a bottom opening of the one or more features. 
     
     
         19 . The apparatus of  claim 10 , wherein operations (a) and (b) are performed without introducing a vacuum break in between the operations. 
     
     
         20 . The apparatus of  claim 10 , wherein the controller ( 750 ) is configured with instructions for exposing the low-k gapfill material to remote hydrogen plasma with a treatment power between about 1 kW and about 8 kW and a treatment time between about 1 second and about 30 seconds. 
     
     
         21 . The apparatus of  claim 10 , wherein an effective dielectric constant of the low-k gapfill material is about 4.0 or lower. 
     
     
         22 . An apparatus ( 700 ) for depositing silicon carbide gapfill material in one or more features of a substrate ( 712 ), the apparatus ( 700 ) comprising:
 a reaction chamber ( 704 ) including a substrate support ( 714 ) for supporting the substrate ( 712 );   a precursor supply source ( 740 ) configured to supply a silicon-containing precursor through a gas outlet ( 742 ) into the reaction chamber ( 704 );   a remote plasma source ( 702 ) separate from and upstream of the reaction chamber ( 704 ), wherein the remote plasma source ( 702 ) is configured to generate reactant radicals and introduce the reactant radicals through a showerhead ( 706 ) into the reaction chamber ( 704 ) towards the substrate ( 712 ), wherein the reactant radicals 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   a controller ( 750 ) configured with instructions for performing the following operations:
 (a) deposit the first thickness of the silicon carbide gapfill material in the one or more features of the substrate ( 712 ); 
 (b) expose the silicon carbide gapfill material to remote hydrogen plasma under conditions to densify and shrink the first thickness of the silicon carbide gapfill material; and 
 (c) repeat operations (a) and (b) until the one or more features of the substrate ( 712 ) are filled or substantially filled with the silicon carbide gapfill material. 
   
     
     
         23 . The apparatus of  claim 22 , wherein the controller ( 750 ) configured with instructions for exposing the silicon carbide gapfill material to the remote hydrogen plasma is configured with instructions for removing hydrogen and increasing cross-linking in the silicon carbide gapfill material. 
     
     
         24 . The apparatus of  claim 22 , wherein the controller ( 750 ) configured with instructions for exposing the silicon carbide gapfill material to the remote hydrogen plasma is configured with instructions for increasing a size of an opening near a top surface of each of the one or more features relative to a bottom surface of each of the one or more features. 
     
     
         25 . The apparatus of  claim 22 , wherein the controller ( 750 ) is configured with instructions for exposing the silicon carbide gapfill material to remote hydrogen plasma with a treatment time and a treatment power based at least in part on a composition of the silicon carbide gapfill material.