Optical emisson spectroscopy (OES) method for monitoring and controlling plasma etch process when forming patterned layers

摘要

A method for monitoring and controlling a plasma etch method for forming a patterned layer. There is first provided a substrate having a blanket layer formed thereover, the blanket layer having a patterned photoresist layer formed thereupon. There is then etched through a plasma etch method while employing the patterned photoresist layer as a patterned photoresist etch mask layer the blanket layer to form a patterned layer. The plasma etch method is monitored through an optical emission spectroscopy (OES) method which monitors a minimum of a first plasma etchant component which relates to a chemical etching of the blanket layer and a second plasma etchant component which relates to a physical sputter etching of the blanket layer and the patterned photoresist layer. While etching through the plasma etch method there is adjusted at least one of a first control parameter which controls the first plasma etchant component concentration and a second control parameter which controls the second plasma etchant component concentration to provide through the plasma etch method from the blanket layer a patterned layer with a pre-determined blanket layer to patterned photoresist layer plasma etch selectivity. There is also disclosed an apparatus through which the method may be practiced.