Synopsys, Inc.

Photronics Corp.

Guangming Xiao

Linyong Pang

Thomas Christopher Cecil

Hua Song

Robert E Gleason

John F McCarty

A first set of critical dimension (CD) measurements of resist patterns created by a lithography process and a second set of CD measurements of water patterns created by an etch process may be obtained. A forward etch model and an inverse etch model may be calibrated together by reducing (1) a first prediction error between the second set of CD measurements and a first set of simulated CDs predicted by the forward etch model based on the resist patterns, a second prediction error between the first set of CD measurements and a second set of simulated CDs predicted by the inverse etch model based on the wafer patterns, and a matching error between the forward etch model and the inverse etch model.

Inverse etch model for mask synthesis

A technique for determining a full-field Mask Error Enhancement Function (MEEF) associated with a mask pattern for use in a photo-lithographic process is described. In this technique, simulated wafer patterns corresponding to the mask pattern are generated at an image plane in an optical path associated with the photo-lithographic process. Then, the full-field MEEF is determined. This full-field MEEF includes MEEF values in multiple directions at positions along one or more contours that define boundaries of one or more features in the one or more simulated wafer patterns. Moreover, at least one of the MEEF values is at a position on a contour where a critical dimension for a feature associated with the contour is undefined.

Full-field mask error enhancement function

The attenuation and phase shift properties of an embedded attenuated phase shift mask (EAPSM) may be independently selected. After or during plowing of regions of an embedded phase shift layer, exposed regions of a substrate are etched to a predetermined depth. Additional regions of the embedded phase sift layer are then exposed and trimmed to a predetermined thickness for providing the desired amount of attenuation, with the final etched depth of the substrate compensating for the change of relative phase shift caused by trimming of the phase shift layer. A matrix test device having a plurality of cells with different levels of attenuation and/or phase shift may then be fabricated on a single EAPSM blank.

Embedded attenuated phase shift mask with tunable transmission

A step mask having a plurality of test cells and a method for producing the same. Each test cell of the step mask is etched for a different amount of time and therefore has a different etch depth or height. The number of phase shifter layer etch iterations can be conducted on a column-by-column and row-by-row basis to decrease the number of etch iterations.

Growing community of inventors

Austin, TX, United States of America

Guangming Xiao