Apparatus and method for controlling wafer uniformity

Abstract

An apparatus for controlling wafer uniformity is disclosed. In one example, the apparatus includes: a plurality of temperature control elements and a processor. Each of the temperature control elements corresponds to a different portion of a wafer respectively such that the temperature control elements correspond to different portions of the wafer. Each of the temperature control elements is configured to individually control temperature of a corresponding portion of the wafer. The processor determines at least one portion of the wafer for temperature uniformity control, and instruct at least one of the temperature control elements, corresponding to the at least one portion, to adjust temperature of the at least one portion for controlling temperature uniformity of the wafer.

What is claimed is: 
     
         1 . An apparatus for controlling wafer uniformity, comprising:
 a plurality of temperature control elements, wherein
 each of the temperature control elements corresponds to a different portion of a wafer respectively such that the temperature control elements correspond to different portions of the wafer, 
 each of the temperature control elements is an electromagnetic coil configured to individually control temperature of a corresponding portion of the wafer, and 
 at least one of the temperature control elements is configured to adjust, based on an instruction from a processor, temperature of at least one portion of the wafer for controlling temperature uniformity of the wafer. 
   
     
     
         2 . The apparatus of  claim 1 , wherein the different portions corresponding to the temperature control elements have a same size. 
     
     
         3 . The apparatus of  claim 1 , wherein the different portions corresponding to the temperature control elements are evenly distributed on the wafer. 
     
     
         4 . The apparatus of  claim 1 , wherein at least one of the different portions corresponding to the temperature control elements has a shape different from an annulus. 
     
     
         5 . The apparatus of  claim 1 , wherein the at least one portion of the wafer is determined based on a critical dimension (CD) map of the wafer, wherein the CD map represents CD performance of the wafer in at least one of the following plasma enhanced processes: etching, deposition, and polishing. 
     
     
         6 . The apparatus of  claim 5 , wherein the temperature of the at least one portion is adjusted to minimize a non-uniformity in the CD map of the wafer. 
     
     
         7 . The apparatus of  claim 6 , wherein the non-uniformity in the CD map is minimized by minimizing at least one of: a plasma density variation among the different portions of the wafer, a chemical reaction rate variation among the different portions of the wafer, and a CD performance difference between center and edge of the wafer. 
     
     
         8 . The apparatus of  claim 1 , wherein
 a group of temperature control elements, among the plurality of temperature control elements, corresponds to a group of portions of the wafer and is configured to adjust temperature of the group of portions together for controlling temperature uniformity of the wafer.   
     
     
         9 . The apparatus of  claim 1 , further comprising a platform holding the plurality of temperature control elements, wherein the platform is above the wafer during the temperature uniformity control. 
     
     
         10 . The apparatus of  claim 1 , further comprising a platform holding the plurality of temperature control elements, wherein the platform is under the wafer during the temperature uniformity control. 
     
     
         11 . The apparatus of  claim 1 , wherein each of the temperature control elements comprises:
 a heating element configured to increase temperature of the corresponding portion of the wafer;   a cooling element configured to decrease temperature of the corresponding portion of the wafer; and   a sensing element configured to detect temperature of the corresponding portion of the wafer.   
     
     
         12 . A wafer process chamber comprising:
 a support configured to support a wafer when the wafer is placed on the support and processed;   a plurality of temperature control elements coupled to the support, wherein   each of the temperature control elements corresponds to a different portion of the wafer respectively such that the temperature control elements correspond to different portions of the wafer,   each of the temperature control elements is an electromagnetic coil configured to individually control temperature of a corresponding portion of the wafer, and   at least one of the temperature control elements is configured to adjust, based on an instruction from a processor, temperature of at least one portion of the wafer for controlling temperature uniformity of the wafer.   
     
     
         13 . The wafer process chamber of  claim 12 , wherein the different portions corresponding to the temperature control elements have a same size. 
     
     
         14 . The wafer process chamber of  claim 12 , wherein the different portions corresponding to the temperature control elements are evenly distributed on the wafer. 
     
     
         15 . The wafer process chamber of  claim 12 , wherein at least one of the different portions corresponding to the temperature control elements has a shape different from an annulus. 
     
     
         16 . The wafer process chamber of  claim 12 , wherein:
 the at least one portion of the wafer is determined based on a critical dimension (CD) map of the wafer;   the CD map represents CD performance of the wafer in at least one of the following plasma enhanced processes: etching, deposition, and polishing; and   the temperature of the at least one portion is adjusted to minimize a non-uniformity in the CD map of the wafer.   
     
     
         17 . The wafer process chamber of  claim 12 , wherein the plurality of temperature control elements is above the wafer during the temperature uniformity control. 
     
     
         18 . The wafer process chamber of  claim 12 , wherein the plurality of temperature control elements is under the wafer during the temperature uniformity control. 
     
     
         19 . A method for controlling wafer uniformity, comprising:
 corresponding each of a plurality of temperature control elements to a different portion of a wafer respectively, wherein each of the temperature control elements is an electromagnetic coil;   configuring each of the temperature control elements to individually control temperature of a corresponding portion of the wafer;   detecting temperature of each portion of the wafer;   determining, based on the detecting, at least one portion of the wafer for temperature uniformity control of the wafer;   selecting at least one temperature control element, among the plurality of temperature control elements, corresponding to the at least one portion; and   adjusting temperature of the at least one portion for controlling temperature uniformity of the wafer.   
     
     
         20 . The method of  claim 19 , wherein adjusting temperature of the at least one portion comprises at least one of the following during an inline plasma enhanced process of the wafer:
 increasing the temperature of the at least one portion;   decreasing the temperature of the at least one portion; or   detecting the temperature of the at least one portion.