CRITICAL DIMENSION VARIATION COMPENSATION ACROSS A WAFER BY MEANS OF LOCAL WAFER TEMPERATURE CONTROL

摘要

An etching system for etching a wafer of a material has a measuring device, an etching chamber, and a controller. The measuring device measures the critical dimension test feature (CD) along the profile of the wafer at a plurality of preset locations. The etching chamber receives the wafer from the measuring device. The etching chamber includes a chuck supporting the wafer and a plurality of heating elements disposed within the chuck. Each heating element is positioned adjacent to each preset location on the wafer. The etching system controller is coupled to the measuring device to receive the actual measured CD's for a particular wafer. The etching system controller is also connected to the plurality of heating elements. The controller adjusts the temperature of each heating element during a process to reduce the variation of critical dimensions among the plurality of preset locations by using temperature dependent etching characteristics of the etch process to compensate for CD variation introduced by the lithography process preceding the etch process.