Control method of multi-stage etching process and processing device using the same

A processing device, for controlling a multi-stage etching process, wherein the processing device comprises:

• a multi-layer setting unit, configured to set a stack information of a plurality of hard mask layers;
• a target setting unit, configured to set an etching target condition;
• and
• a machine learning model, configured to generate a parameter setting recipe of the hard mask layers under the etching target condition, wherein the machine learning model is trained based on the stack information of the hard mask layers, a plurality of process parameters and a process result, the stack information includes the materials of the hard mask layers, the thicknesses of the hard mask layers and the stacking sequence of the hard mask layers, and the hard mask layers are etched based on the parameter setting recipe.