Method of optimizing seasoning recipe for etch process

A method for optimizing a seasoning recipe for a dry etch process, comprising the steps of:

• (a) selecting a preliminary seasoning recipe;
• (b) etching one or more test wafers using the preliminary seasoning recipe in a dry etch chamber and then performing a preliminary main etch process for a plurality of run wafers in the dry etch chamber using a main etch recipe to determine an end-point detection time of each run wafer;
• (c) processing the end-point detection times of the run wafers to determine one or more optimization parameters;
• and
• (d) evaluating the optimization parameters to determine whether to (i) use the preliminary seasoning recipe as a seasoning recipe for the dry etch process or to (ii) modify the preliminary seasoning recipe and repeat steps (b)–(d) using the modified seasoning recipe,
• wherein the optimization parameters comprise an initial dispersion parameter that is determined as an absolute value of the difference between the end-point detection time of a first run wafer and the end-point detection time of a subsequent run wafer,
• wherein the optimization parameters comprise a standard deviation that is determined using end-point detection times of a plurality of the run wafers,
• wherein the optimization parameters comprise a critical value of reproducibility that is determined based on the standard deviation,
• wherein the step of evaluating the optimization parameters comprises:
• comparing the initial dispersion to the critical value of reproducibility;
• and
• selecting the preliminary seasoning recipe as a seasoning recipe for the dry etch process, if the initial dispersion is less than or equal to the critical value of reproducibility.