Method of controlling a chamber based upon predetermined concurrent behavior of selected plasma parameters as a function of source power, bias power and chamber pressure

For each one of plural plasma parameters, such as ion density, wafer voltage, etch rate, wafer current, a relevant surface of constant value is fetched from a memory. The relevant surface of constant value corresponds to a user-selected value of one of the plasma parameters, the surface being defined in a space of which each one of plural, chamber parameters (e.g., source power, bias power and chamber pressure) is a dimension. An intersection of these relevant surfaces is found, the intersection corresponding to a target value of source power, bias power and chamber pressure. The source power, the bias power and the chamber pressure, respectively, are set to their corresponding target values.