Advanced Micro Devices Corporation

Globalfoundries Inc.

Siddharth Chauhan

James Broc Stirton

Kevin R Lensing

A method for monitoring a photolithography system includes defining a model of the photolithography system for modeling top and bottom critical dimension data associated with features formed by the photolithography system as a function of dose and focus. A library of model inversions is generated for different combinations of top and bottom critical dimension values. Each entry in the library specifies a dose value and a focus value associated with a particular combination of top and bottom critical dimension values. A top critical dimension measurement and a bottom critical dimension measurement of a feature formed by the photolithography system using a commanded dose parameter and a commanded focus parameter are received. The library is accessed using the top and bottom critical dimension measurements to generate values for a received dose parameter and the received focus parameter. The received dose and focus parameters are compared to the commanded dose and focus parameters to characterize the photolithography system.

Method and apparatus for extracting dose and focus from critical dimension data

A method includes defining a reference model of a system having a plurality of terms for modeling data associated with the system. A reference fit error metric is generated for the reference model. A set of evaluation models each having one term different than the reference model is generated. An evaluation fit error metric for each of the evaluation models is generated. The reference model is replaced with a selected evaluation model responsive to the selected evaluation model having an evaluation fit error metric less than the reference fit error metric. The model evaluation is repeated until no evaluation model has an evaluation fit error metric less than the reference fit error metric. The reference model is trained using the data associated with the system, and the trained reference model is employed to determine at least one characteristic of the system.

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Austin, TX, United States of America

Siddharth Chauhan