No abstract

Decreasing k1 factors require improved empirical models for the most critical challenge at 65nm node, contact holes especially. These requirements are reflected in the need for increasingly accurate lithography contour simulations. One of the major contributors to final OPC accuracy is the quality of the optical model. In this study, a new approach to the calibration of an optical model by using KIF will be proposed based upon the real through scanners and steppers of illumination distribution and implement to the OPC kernel.

No abstract

No abstract

In the High NA process, pattern environment will become very aggressive because of scattering effect. Especially on metal layers, maybe it will cause pattern bridge when the pattern density is varied. We need to find out the root cause and have a good solution to minimize the wafer CD difference that comes from environmental effect (pattern density).In this paper, we analyze the root cause by checking the pattern density influence on mask CD and wafer printing CD. We design different pattern density layout to measure the mask CD error, use AIMS (Aerial Image Measurement System) to measure the aerial image CD and print wafer to check the real result. Then, we try to add some assistant feature (pattern density balance) and use simulation tool to simulate whether this method can have improvement.