Control of etch rate using modeling, feedback and impedance match

摘要

A method for achieving an etch rate is described. The method includes receiving a calculated variable associated with processing a work piece in a plasma chamber. The method further includes propagating the calculated variable through a model to generate a value of the calculated variable at an output of the model, identifying a calculated processing rate associated with the value, and identifying based on the calculated processing rate a pre-determined processing rate. The method also includes identifying a pre-determined variable to be achieved at the output based on the pre-determined processing rate and identifying a characteristics associated with a real and imaginary portions of the pre-determined variable. The method includes controlling variable circuit components to achieve the characteristics to further achieve the pre-determined variable.

主权项

1. A method for achieving an etch rate, comprising:
receiving a value of a variable measured at an output of a radio frequency (RF) generator, wherein the measured value is associated with processing a work piece in a plasma chamber, wherein the plasma chamber is coupled to an impedance matching circuit via an RF transmission line, wherein the output of the RF generator is coupled to the impedance matching circuit via an RF cable; propagating the measured value of the variable through a computer-generated model to generate a calculated value of the variable at an output of the computer-generated model; identifying a calculated processing rate associated with the calculated value of the variable; identifying based on the calculated processing rate a pre-determined processing rate to be achieved; identifying a pre-determined variable to be achieved at the output of the computer-generated model based on the pre-determined processing rate; identifying a first characteristic associated with a real portion of the pre-determined variable, the first characteristic of a first variable circuit component within the impedance matching circuit; controlling the first variable circuit component to achieve the first characteristic to further achieve the real portion of the pre-determined variable; identifying a second characteristic associated with an imaginary portion of the pre-determined variable, the second characteristic of a second variable circuit component within the impedance matching circuit; and sending a signal to the second variable circuit component to achieve the second characteristic to further achieve the imaginary portion of the pre-determined variable.