Patent ID: 9110465
Filing Date: 2015-08-18
Classification: G05B,H01L

Abstract:
1. A method for providing asymmetric control of a process parameter of a process for treating a wafer, the method comprising: receiving a data point for the process parameter relative to the wafer; selecting a first value for a process weighting factor when the data point is consistent with a first criteria; selecting a second value for the process weighting factor when the data point is consistent with a second criteria, wherein the second value is not equal to the first value; calculating an exponential weighted moving average of the process parameter based on the data point and the process weighting factor; updating the process parameter with the exponential weighted moving average; and using the updated process parameter to control the process and thereby treat the wafer, wherein the first criteria is a function of the data point, a previously calculated process parameter value and a first weighting factor switch limit, and wherein the first criteria is mutually exclusive of the second criteria.