Abstract: Various test structures and methods for monitoring or controlling a semiconductor fabrication process are provided. One test structure formed on a wafer as a monitor for a lithography process includes a bright field target that includes first grating structures. The test structure also includes a dark field target that includes second grating structures. The first and second grating structures have one or more characteristics that are substantially the same as one or more characteristics of device structures formed on the wafer. In addition, the test structure includes a phase shift target having characteristics that are substantially the same as the characteristics of the bright field or dark field target except that grating structures of the phase shift target are shifted in optical phase from the first or second grating structures. One or more characteristics of the targets can be measured and used to determine parameter(s) of the lithography process.

Abstract: A method for optimizing alignment performance in a fleet of exposure systems involves characterizing each exposure system in a fleet of exposure systems to generate a set of distinctive distortion profiles associated with each exposure system. The set of distinctive distortion profiles are stored in a database. A wafer having reference pattern formed thereon is provided for further pattern fabrication and an exposure system is selected from the fleet to fabricate a next layer on the wafer. Linear and higher order parameters of the selected exposure system are adjusted using the distinctive distortion profiles to model the distortion of the reference pattern. Once the exposure system is adjusted, it is used to form a lithographic pattern on the wafer.

Abstract: A method for optimizing alignment performance in a fleet of exposure systems involves characterizing each exposure system in a fleet of exposure systems to generate a set of distinctive distortion profiles associated with each exposure system. The set of distinctive distortion profiles are stored in a database. A wafer having reference pattern formed thereon is provided for further pattern fabrication and an exposure system is selected from the fleet to fabricate a next layer on the wafer. Linear and higher order parameters of the selected exposure system are adjusted using the distinctive distortion profiles to model the distortion of the reference pattern. Once the exposure system is adjusted, it is used to form a lithographic pattern on the wafer.

Abstract: Various test structures and methods for monitoring or controlling a semiconductor fabrication process are provided. One test structure formed on a wafer as a monitor for a lithography process includes a bright field target that includes first grating structures. The test structure also includes a dark field target that includes second grating structures. The first and second grating structures have one or more characteristics that are substantially the same as one or more characteristics of device structures formed on the wafers. In addition, the test structure includes a phase shift target having characteristics that are substantially the same as the characteristics of the bright field or dark field target except that grating structures of the phase shift target are shifted in optical phase from the first or second grating structures. One or more characteristics of the targets can be measured and used to determine parameter(s) of the lithography process.