Lam Research Corporation
Compensating chamber and process effects to improve critical dimension variation for trim process

Abstract:

A controller includes memory that stores data correlating accumulation values to respective adjustment factors. The accumulation values correspond to accumulation of material on surfaces within a processing chamber and the respective adjustment factors correspond to adjustments to a control parameter of RF power provided to the processing chamber. An accumulation calculation module is configured to calculate a first accumulation value indicating an amount of accumulation of the material. An RF power control module is configured to receive the first accumulation value, receive at least one of a setpoint power and a duration of an etching step, retrieve the stored data from the memory, adjust the control parameter based on the first accumulation value, the at least one of the setpoint power and the duration of the etching step, and the stored data, and control the RF power provided to the processing chamber in accordance with the adjusted control parameter.