Conformal deposition of silicon carbide films using heterogeneous precursor interaction

Abstract

A doped or undoped silicon carbide film can be deposited using a remote plasma chemical vapor deposition (CVD) technique. One or more silicon-containing precursors are provided to a reaction chamber. Radical species, such as hydrogen radical species, are provided in a substantially low energy state or ground state and interact with the one or more silicon-containing precursors to deposit the silicon carbide film. A co-reactant may be flowed with the one or more silicon-containing precursors, where the co-reactant can be a depositing additive or a non-depositing additive to increase step coverage of the silicon carbide film.

What is claimed is: 
     
         1 . A method of depositing a silicon carbide film on a substrate, the method comprising:
 providing a substrate in a reaction chamber;   flowing a silicon-containing precursor into the reaction chamber towards the substrate, wherein the silicon-containing precursor has (i) one or more Si—H bonds and/or Si—Si bonds, (ii) one or more Si—C bonds, Si—N, and/or Si—O bonds, (iii) no C—O bonds, and (iv) no C—N bonds;   flowing a co-reactant into the reaction chamber along with the silicon-containing precursor, wherein the co-reactant is a hydrocarbon molecule;   generating, from a hydrogen source gas, radicals of hydrogen in a remote plasma source that are generated upstream of the silicon-containing precursor and the co-reactant; and   introducing the radicals of hydrogen into the reaction chamber and towards the substrate, wherein the radicals of hydrogen are in a ground state to react with the silicon-containing precursor and the co-reactant to form a doped or undoped silicon carbide film on the substrate, wherein the doped or undoped silicon carbide film has a conformality of at least 90%.   
     
     
         2 . The method of  claim 1 , wherein all or substantially all of the radicals of hydrogen in an environment adjacent to the substrate are radicals of hydrogen in the ground state. 
     
     
         3 . The method of  claim 1 , wherein the doped or undoped silicon carbide film is a doped silicon carbide film of silicon oxycarbide (SiCO), silicon carbonitride (SiCN), or silicon oxycarbonitride (SiOCN). 
     
     
         4 . The method of  claim 1 , wherein the hydrocarbon molecule has one or more carbon-to-carbon double bonds or triple bonds. 
     
     
         5 . The method of  claim 4 , wherein the hydrocarbon molecule includes propylene, ethylene, butene, pentene, butadiene, pentadiene, hexadiene, heptadiene, toluene, benzene, acetylene, propyne, butyne, pentyne, or hexyne. 
     
     
         6 . The method of  claim 1 , wherein the co-reactant interacts with the silicon-containing precursor as a non-depositing species in the doped or undoped silicon carbide film. 
     
     
         7 . The method of  claim 1 , wherein the silicon-containing precursor and the co-reactant are simultaneously flowed along the same flow path into the reaction chamber. 
     
     
         8 . The method of  claim 1 , wherein the doped or undoped silicon carbide film has a conformality of at least 95%. 
     
     
         9 . The method of  claim 1 , wherein the silicon-containing precursor includes an alkylcarbosilane, a siloxane, or a silazane. 
     
     
         10 . A method of depositing a silicon carbide film on a substrate, the method comprising:
 providing a substrate in a reaction chamber;   flowing a first organosilicon precursor into the reaction chamber, wherein the first organosilicon precursor has (i) one or more Si—H bonds and/or Si—Si bonds, and (ii) one or more Si—C bonds, Si—N bonds, and/or Si—O bonds;   flowing a second organo silicon precursor into the reaction chamber, wherein the second organosilicon precursor includes (i) no Si—H bonds and (ii) no Si—Si bonds;   generating, from a hydrogen source gas, radicals of hydrogen in a remote plasma source that are generated upstream of the first organosilicon precursor and the second organosilicon precursor; and   introducing the radicals of hydrogen into the reaction chamber and towards the substrate, wherein the radicals of hydrogen are in a ground state to react with the first organosilicon precursor and the second organosilicon precursor to form a doped or undoped silicon carbide film on the substrate.   
     
     
         11 . The method of  claim 10 , wherein all or substantially all of the radicals of hydrogen are radicals of hydrogen in the ground state. 
     
     
         12 . The method of  claim 10 , wherein the doped or undoped silicon carbide film is a doped silicon carbide film of silicon oxycarbide (SiCO), silicon carbonitride (SiCN), or silicon oxycarbonitride (SiOCN). 
     
     
         13 . The method of  claim 10 , wherein a flow rate of the second organosilicon precursor is at least two times greater than a flow rate of the first organosilicon precursor. 
     
     
         14 . The method of  claim 10 , wherein a flow rate of the second organosilicon precursor is between about 25 sccm and about 200 sccm. 
     
     
         15 . The method of  claim 10 , wherein the doped or undoped silicon carbide film has a conformality of at least 95%. 
     
     
         16 . The method of  claim 10 , wherein the second organosilicon precursor includes tetramethylsilane (4MS). 
     
     
         17 . The method of  claim 10 , wherein the second organosilicon precursor interacts with the first organosilicon precursor as a depositing species in the doped or undoped silicon carbide film. 
     
     
         18 . The method of  claim 10 , wherein the first organosilicon precursor and the second organosilicon precursor are simultaneously flowed along the same flow path into the reaction chamber. 
     
     
         19 . The method of  claim 10 , wherein each of the first organosilicon precursor and the second organosilicon precursor is flowed downstream from the remote plasma source. 
     
     
         20 . The method of  claim 10 , further comprising:
 flowing a co-reactant from the remote plasma source and upstream of the first organosilicon precursor and the second organosilicon precursor to provide radicals and/or ions of the co-reactant, wherein the co-reactant includes carbon dioxide (CO 2 ), carbon monoxide (CO), water (H 2 O), methanol (CH 3 OH), oxygen (O 2 ), ozone (O 3 ), nitrogen (N 2 ), nitrous oxide (N 2 O), ammonia (NH 3 ), or mixtures thereof.