Conformal amorphous carbon for spacer and spacer protection applications

Abstract

A method of forming a nitrogen-doped amorphous carbon layer on a substrate in a processing chamber is provided. The method generally includes depositing a predetermined thickness of a sacrificial dielectric layer over a substrate, forming patterned features on the substrate by removing portions of the sacrificial dielectric layer to expose an upper surface of the substrate, depositing conformally a predetermined thickness of a nitrogen-doped amorphous carbon layer on the patterned features and the exposed upper surface of the substrate, selectively removing the nitrogen-doped amorphous carbon layer from an upper surface of the patterned features and the upper surface of the substrate using an anisotropic etching process to provide the patterned features filled within sidewall spacers formed from the nitrogen-doped amorphous carbon layer, and removing the patterned features from the substrate.

1 . A method of forming an amorphous carbon layer on a substrate in a processing chamber, comprising:
 depositing a predetermined thickness of a sacrificial dielectric layer over a substrate;   forming patterned features on the substrate by removing portions of the sacrificial dielectric layer to expose an upper surface of the substrate;   depositing conformally a predetermined thickness of an amorphous carbon layer on the patterned features and the exposed upper surface of the substrate;   selectively removing the amorphous carbon layer from an upper surface of the patterned features and the upper surface of the substrate using an anisotropic etching process to provide the patterned features filled within sidewall spacers formed from the amorphous carbon layer; and   removing the patterned features from the substrate.   
     
     
         2 . The method of  claim 1 , wherein the amorphous carbon layer is formed by introducing a hydrocarbon source, a nitrogen-containing gas, and a plasma initiating gas into the processing chamber. 
     
     
         3 . The method of  claim 2 , wherein the hydrocarbon source comprises one or more hydrocarbon compounds selected from the group consisting of acetylene (C 2 H 2 ), ethylene (C 2 H 4 ), ethane (C 2 H 6 ), propylene (C 3 H 6 ), propyne (C 3 H 4 ), propane (C 3 H 8 ), butane (C 4 H 10 ), butylene (C 4 H 8 ), butadiene (C 4 H 6 ), phenylacetylene (C 8 H 6 ), and combinations thereof. 
     
     
         4 . The method of  claim 1 , wherein the amorphous carbon layer is formed by introducing a nitrogen-containing hydrocarbon source and a plasma-initiating gas into the processing chamber. 
     
     
         5 . The method of  claim 4 , wherein the nitrogen-containing hydrocarbon comprises one or more nitrogen containing hydrocarbon compounds selected from the group consisting of methylamine, dimethylamine, trimethylamine (TMA), triethylamine, aniline, quinoline, pyridine, acrilonitrile, benzonitrile, and combinations thereof. 
     
     
         6 . The method of  claim 5 , wherein the nitrogen containing hydrocarbon compound is benzonitrile. 
     
     
         7 . The method of  claim 1 , wherein the amorphous carbon layer is a nitrogen-doped amorphous carbon having a carbon:nitrogen ratio of between about 0.1% nitrogen to about 4.0% nitrogen. 
     
     
         8 . The method of  claim 1 , wherein the sacrificial dielectric layer comprises silicon oxide, silicon nitride, polysilicon, or amorphous carbon. 
     
     
         9 . A method of forming a device in a processing chamber, comprising:
 forming patterned features on an upper surface of a substrate;   depositing conformally a predetermined thickness of a sacrificial dielectric layer on the patterned features and an exposed upper surface of the substrate;   selectively removing the sacrificial dielectric layer from an upper surface of the patterned features and the exposed upper surface of the substrate to provide the patterned features filled within first sidewall spacers formed from the sacrificial dielectric layer;   forming second sidewall spacers adjacent to the first sidewall spacers, the second sidewall spacers being formed from a nitrogen-doped amorphous carbon material having a carbon:nitrogen ratio of between about 0.1% nitrogen to about 4.0% nitrogen; and   removing the patterned features filled within the first sidewall spacers.   
     
     
         10 . The method of  claim 9 , wherein the patterned features are formed from amorphous carbon. 
     
     
         11 . The method of  claim 9 , wherein the nitrogen-doped amorphous carbon material is formed by introducing a nitrogen-containing hydrocarbon source and a plasma-initiating gas into the processing chamber. 
     
     
         12 . The method of  claim 11 , wherein the nitrogen-containing hydrocarbon source comprises one or more nitrogen containing hydrocarbon compounds selected from the group consisting of methylamine, dimethylamine, trimethylamine (TMA), triethylamine, aniline, quinoline, pyridine, acrilonitrile, benzonitrile, and combinations thereof. 
     
     
         13 . The method of  claim 12 , wherein the nitrogen containing hydrocarbon compound is benzonitrile. 
     
     
         14 . A method of forming a nitrogen-doped amorphous carbon layer on a substrate in a processing chamber, comprising:
 depositing conformally a nitrogen-doped amorphous carbon layer on patterned features formed on the substrate, wherein the deposition is performed by introducing a nitrogen-containing hydrocarbon source and a plasma-initiating gas into the processing chamber, and the nitrogen-containing hydrocarbon source comprises benzonitrile;   selectively removing the nitrogen-doped amorphous carbon layer from an upper surface of the patterned features and an upper surface of the substrate using an anisotropic etching process to provide patterned features filled within sidewall spacers formed from the nitrogen-doped amorphous carbon layer; and   removing the patterned features from the substrate.   
     
     
         15 . The method of  claim 14 , wherein the nitrogen-doped amorphous carbon layer is deposited by introducing into the processing chamber a nitrogen-containing hydrocarbon source at a flow rate of about 100 mg/min to about 1,000 mg/min, a nitrogen-containing gas at a flow rate of 0 sccm to about 2,000 sccm, by applying an RF power of about 30 W to about 200 W (for a 200 mm substrate), and at an electrode spacing of about 100 mils to about 800 mils.