Method and device for controlling a thickness of a protective film on a substrate

Abstract

A plasma processing apparatus includes a reaction chamber having a gas inlet and a gas outlet; a gas supply connected to the gas inlet; a substrate support disposed in the reaction chamber; a plasma generator that forms a plasma in the reaction chamber; and processing circuitry. The processing circuitry controls provision of a substrate on the substrate support, the substrate including an etching layer and a mask on the etching layer; controls provision of a Si-containing gas to the reaction chamber to deposit a Si-containing film on at least a sidewall of a recess in the etching layer; controls the gas supply to supply a gas mixture to the reaction chamber; and controls the plasma generator to generate a first plasma from the gas mixture, thereby modifying the Si-containing film to form a protective film on the sidewall of the recess.

What is claimed is: 
     
         1 . A plasma processing apparatus comprising:
 a reaction chamber having a gas inlet and a gas outlet;   a gas supply connected to the gas inlet;   a substrate support disposed in the reaction chamber;   a plasma generator configured to form a plasma in the reaction chamber; and processing circuitry configured to:
 control provision of a substrate on the substrate support, the substrate including an etching layer and a mask on the etching layer; 
 control provision of a Si-containing gas to the reaction chamber to deposit a Si-containing film on at least a sidewall of a recess in the etching layer; 
 control the gas supply to supply a gas mixture to the reaction chamber, the gas mixture including a fluorine-containing gas and at least one selected from a group consisting of an oxygen-containing gas and a nitrogen-containing gas; and 
 control the plasma generator to generate a first plasma from the gas mixture, thereby modifying the Si-containing film to form a protective film on the sidewall of the recess. 
   
     
     
         2 . The plasma processing apparatus according to  claim 1 , wherein the gas mixture is continuously supplied. 
     
     
         3 . The plasma processing apparatus according to  claim 1 , wherein the processing circuitry is further configured to exhaust the Si-containing gas from the reaction chamber. 
     
     
         4 . The plasma processing apparatus according to  claim 1 , wherein the processing circuitry is further configured to exhaust the gas mixture from the reaction chamber. 
     
     
         5 . The plasma processing apparatus according to  claim 1 , wherein the Si-containing gas is an amino-silane gas. 
     
     
         6 . The plasma processing apparatus according to  claim 1 , wherein the fluorine-containing gas is a CxFy gas. 
     
     
         7 . The plasma processing apparatus according to  claim 1 , wherein the oxygen-containing gas is at least one selected from a group consisting of O 2 , CO, CO 2  and O 3 . 
     
     
         8 . The plasma processing apparatus according to  claim 1 , wherein the nitrogen-containing gas is at least one selected from a group consisting of NH 3 , N 2  and NF 3 . 
     
     
         9 . The plasma processing apparatus according to  claim 1 , wherein the processing circuitry further configured to control etching the substrate with a second plasma after forming the protective film on the sidewall of the recess. 
     
     
         10 . The plasma processing apparatus according to  claim 9 , wherein the etching includes applying a bias power to an electrode in the reaction chamber. 
     
     
         11 . The plasma processing apparatus according to  claim 1 , wherein a radio frequency (RF) is supplied to an electrode in the reaction chamber to generate the first plasma. 
     
     
         12 . A plasma processing apparatus comprising:
 a reaction chamber having a gas inlet and a gas outlet;   a substrate support disposed in the reaction chamber;   a plasma generator configured to form a plasma in the reaction chamber;   a controller configured to cause:
 placing a substrate on the substrate support, the substrate including an etching layer and a mask on the etching layer; 
 supplying a precursor into the reaction chamber to deposit a Si-containing film on at least a sidewall of a recess in the etching layer, the precursor including silicon or amino-silane; 
 supplying a gas mixture into the reaction chamber, the gas mixture including a fluorine-containing gas and at least one selected from a group consisting of an oxygen-containing gas and a nitrogen-containing gas; and 
 generating a first plasma from the gas mixture, thereby modifying the Si-containing film to form a protective film on the sidewall of the recess. 
   
     
     
         13 . The plasma processing apparatus according to  claim 12 , wherein the gas mixture is continuously supplied. 
     
     
         14 . The plasma processing apparatus according to  claim 12 , wherein the controller is further configured to cause: exhausting the precursor from the reaction chamber. 
     
     
         15 . The plasma processing apparatus according to  claim 12 , wherein the controller is further configured to cause: exhausting the gas mixture from the reaction chamber. 
     
     
         16 . The plasma processing apparatus according to  claim 12 , wherein the fluorine-containing gas is a CxFy gas. 
     
     
         17 . The plasma processing apparatus according to  claim 12 , wherein the oxygen-containing gas is at least one selected from a group consisting of O 2 , CO, CO 2  and O 3 . 
     
     
         18 . The plasma processing apparatus according to  claim 12 , wherein the nitrogen-containing gas is at least one selected from a group consisting of NH 3 , N 2  and NF 3 . 
     
     
         19 . The plasma processing apparatus according to  claim 12 , wherein the controller is further configured to cause:
 etching the substrate with a second plasma after forming the protective film on the sidewall of the recess.   
     
     
         20 . The plasma processing apparatus according to  claim 19 , wherein the etching includes supplying a bias power to an electrode in the reaction chamber.