Etching method and etching apparatus

Abstract

A technique improves pattern features formed by etching and the uniformity of the features across the surface of a substrate. An etching method includes steps a), b), c), d), and e). Step a) includes placing, on a support, a substrate including a target film. Step b) includes partially etching the target film and forming a recess. Step c) includes setting the temperature of the support at a first temperature, and forming, on a sidewall of the recess, a first film having a first film thickness distribution. Step d) includes partially further etching the target film having the first film formed on the target film. Step e) includes setting the temperature of the support at a second temperature different from the first temperature, and forming, on the sidewall of the recess, a second film having a second film thickness distribution different from the first film thickness distribution.

What is claimed is: 
     
         1 . An etching apparatus, comprising:
 a reaction chamber;   a support located within the reaction chamber and configured to support a substrate including a target film;   a gas supply unit configured to introduce process gases to the reaction chamber, the process gases including at least one of an etching gas, a precursor, and a reactant;   a temperature setting device configured to control a temperature of the support; and   a computer-based controller configured to control
 a) placement of a substrate on the support; 
 b) the gas supply unit to introduce a first process gas to the reaction chamber to partially etch the target film and form a recess therein; 
 c) the temperature setting device to set a temperature of the support at a. first temperature after performing the partial etching; 
 d) the gas supply unit to introduce a second process gas to the reaction chamber to form a first film on a sidewall of the recess, the second process gas being different from the first process gas and the first film having a first film thickness distribution; 
 e) the gas supply unit to introduce a third process gas to the reaction chamber to partially further etch the target film after the first film has been formed on the sidewall of the recess, the third process gas being different from the second process gas; 
 f) the temperature setting device to set the temperature of the support at a second temperature different from the first temperature after the partially further etching; and 
 g) the gas supply unit to introduce a fourth process gas to the reaction chamber to form a second film on the sidewall of the recess, the fourth process gas being different from the third process gas and the second film having a second film thickness distribution different from the first film thickness distribution. 
   
     
     
         2 . The etching apparatus according to  claim 1 , wherein the support further comprises a plurality of zones and the controller is further configured to control the temperature setting device to
 adjust a temperature of a first zone of the support corresponding to a first area of the substrate to a temperature different from a temperature of a second zone of the support corresponding to a second area of the substrate to form the first film in the first area to have at least one of a thickness or a position different from a thickness and a position of the first film formed in the second area.   
     
     
         3 . The etching apparatus according to  claim 2 , wherein the first zone includes a center of the support, and the second zone includes an edge of the support 
     
     
         4 . The etching apparatus according to  claim 1 , further comprising:
 a plurality of heaters corresponding to the plurality of zones of the support.   
     
     
         5 . The etching apparatus according to  claim 2 , wherein the controller is configured to control the temperature setting device to provide independent temperature control in each zone of the plurality of zones. 
     
     
         6 . The etching apparatus according to  claim 5 , wherein the plurality of zones is defined concentrically within the support. 
     
     
         7 . The etching apparatus according to  claim 6 , wherein one or more of the zones of the plurality of zones comprises multiple zones defined circumferentially from the center of the support toward the circumference of the support. 
     
     
         8 . The etching apparatus according to  claim 1 , wherein the controller is further configured to control the temperature setting device to set the second temperature to a higher temperature than the first temperature. 
     
     
         9 . The etching apparatus according to  claim 8 , wherein the support further comprises a plurality of zones and the controller is further configured to control the temperature setting device to
 adjust a temperature of a first zone of the support corresponding to a first area of the substrate to a temperature different from a temperature of a second zone of the support corresponding to a second area of the substrate to form the first film in the first area to have at least one of a thickness or a position different from a thickness and a position of the first film formed in the second area.   
     
     
         10 . The etching apparatus according to  claim 9 , wherein the first zone includes a center of the support, and the second zone includes an edge of the support. 
     
     
         11 . The etching apparatus according to  claim 10 , wherein
 d) includes control of the gas supply to
 d-1) supply a first reactant which causes the first reactant to be adsorbed on the sidewall of the recess, and 
 d-2) supply a second reactant which causes the second reactant to react with the first reactant to form the first film, 
   g) includes control of the gas supply unit to
 g-1) supply a third reactant and causing the third reactant to be adsorbed on the sidewall of the recess, and 
 g-2) supply a fourth reactant and causing the fourth reactant to react with the third reactant to form the second film, and 
   wherein the controller is further configured to control a duration of d-2) and a duration of g-2), the duration of g-2) being different from the duration of d-2) so as to form the first film to have at least one of a thickness or a position different from a corresponding thickness or position of the second film.   
     
     
         12 . The etching apparatus according to  claim 9 , wherein the controller is configured to provide independent temperature control in each zone of the plurality of zones, 
     
     
         13 . The etching apparatus according to  claim 12 , wherein the plurality of zones is defined concentrically within the support. 
     
     
         14 . The etching apparatus according to  claim 12 , wherein one or more of the zones comprises multiple zones defined circumferentially from the center of the support toward the circumference of the support. 
     
     
         15 . An etching apparatus, comprising:
 an etching chamber;
 a support disposed within the etching chamber, wherein the support is configured to support a substrate including a target film; 
   a gas supply unit configured to introduce processing gases into the etching chamber to generate plasma from the processing gases introduced to the etching chamber first processing gas introduced into the etching chamber from the gas supply unit is configured to partially etch the target film and form a recess therein and
 a temperature controller configured to set the temperatures of at least two of a plurality of zones of the support to different temperatures after performing the partial etch, wherein 
 in response to a second processing gas different from the first processing gas introduced into the etching chamber, a film is formed on a sidewall of the recess, the film having different film thickness distributions, in a depth direction, in areas corresponding with the at least two of the plurality of zones, and 
   in response to another plasma generated from a third processing gas that is different from the second processing gas introduced into the chamber by the gas supply unit, further etch the target film after the film has been formed on the recess of the target film.   
     
     
         16 . The etching apparatus according to  claim 15 , wherein a first zone of the at least two of the plurality of zones includes a center of the support, and a second zone of the at least two of the plurality of zones includes an edge of the support. 
     
     
         17 . The etching apparatus according to  claim 15 , wherein the temperature controller is configured to provide independent temperature control in each zone of the plurality of zones. 
     
     
         18 . The etching apparatus according to  claim 17 , wherein the plurality of zones is defined concentrically within the support. 
     
     
         19 . The etching apparatus according to  claim 17 , wherein one or more of the zones of the plurality of zones comprises multiple zones defined circumferentially from the center of the support toward the circumference of the support. 
     
     
         20 . An etching apparatus, comprising:
 a reaction chamber;   a support located within the reaction chamber and configured to support a substrate including a target film;   a gas supply unit configured to introduce process gases to the reaction chamber, the process gases including at least one of an etching gas, a precursor, and a reactant;   a temperature setting device configured to control a temperature of the support; and   means for controlling
 a) placement of a substrate on the support; 
   b) the gas supply unit to introduce a first process gas to the reaction chamber to partially etch the target film and form a recess therein;
 c) the temperature setting device to set a temperature of the support at a. first temperature after performing the partial etching; 
 d) the gas supply unit to introduce a second process gas to the reaction chamber to form a first film on a sidewall of the recess, the second process gas being different from the first process gas and the first film having a first film thickness distribution; 
 e) the gas supply unit to introduce a third process gas to the reaction chamber to partially further etch the target film after the first film has been formed on the sidewall of the recess, the third process gas being different from the second process gas; 
 f) the temperature setting device to set the temperature of the support at a second temperature different from the first temperature after the partially further etching; and 
   g) the gas supply unit to introduce a fourth process gas to the reaction chamber to form a second film on the sidewall of the recess, the fourth process gas being different from the third process gas and the second film having a second film thickness distribution different from the first film thickness distribution.