Patent ID: 7452824

Claim:
A method of operating a plasma reactor chamber with respect to plural plasma parameters, by controlling plural chamber parameters, said method comprising: characterizing the reactor chamber by performing the steps of: a. for each one of said chamber parameters, ramping an input level of the one chamber parameter while sampling RF electrical parameters at an RF bias power input to said wafer support pedestal and computing from each sample of said RF electrical parameters the values of said plural plasma parameters, and storing said values with the corresponding levels of said one chamber parameter as corresponding chamber parameter data; b. for each one of said chamber parameters, deducing, from the corresponding chamber parameter data, a single variable function for each of said plural plasma parameters having said one chamber parameter as an independent variable, so as to produce a set of said functions corresponding to all of said chamber parameters; c. from said set of functions, constructing surfaces defining simultaneous values of all of said chamber parameters, each respective surface corresponding to each constant value of one of said plural plasma parameters, said surfaces spanning a range of said values, and storing said surfaces; controlling a plasma in the chamber during processing of a production wafer in the chamber in accordance with user-selected values of each of said plural plasma parameters by performing the following steps: a. for each one of said plural plasma parameters, fetching a relevant surface of constant value corresponding to the user-selected value of said one plasma parameter, and determining an intersection of the relevant surfaces which defines a target value for each of said chamber parameters; and b. setting each of said chamber parameters to the corresponding target value.