Method and apparatus for plasma etching

A plasma etching apparatus, comprising:

• an etching chamber configured to support a target therein, the target comprising at least two material layers comprising:
• a first material layer to be plasma etched according to a guide pattern;
• and a second material layer disposed on the first material layer as the guide pattern;
• and at least one processor configured to:
• determine a process condition for plasma etching the target before execution of a plasma etching process, the process condition comprising a unit etching time determined according to respective incubation times of the at least two material layers;
• and control an aspect of the etching chamber according to the process condition, wherein the process condition comprises a unit etching time over which the plasma etching process is to be continuously performed, wherein each of the respective incubation times is a minimum reaction time for an etching gas and a corresponding material layer of the at least two material layers to react, wherein the respective incubation times comprise:
• a first incubation time of the first material layer;
• and a second incubation time of the second material layer, the second incubation time being greater than the first incubation time, and wherein the unit etching time is determined to be greater than the first incubation time and less than the second incubation time.