The OPE signature of a lithographic stepper or scanner has become a very important characteristic of the tool, as it determines the OPC correction to be applied to reticles exposed on that tool. The signature depends on a variety of detailed information about the scanner lens and illuminator, which in turn depend on the characteristics of the illumination light from the laser.Specifically, changes in the laser bandwidth should impact OPE as the lens exhibits some chromatic aberration. Tool-totool differences and time fluctuation of the laser bandwidth could cause variations in OPE tool matching and stability.To assess this, a detailed study of laser bandwidth effects on OPE was performed. A sensitive spectrometer was connected to a litho laser, allowing careful measurements of both the FWHM and E 95 parameters of the laser spectral profile.Lithographic modeling using the chromatic response of the lens was run in order to predict effects. Exposures of CD through pitch were made to test the modeling. Finally, the bandwidth data was correlated with litho sensitivity to create a "bandwidth effect", put in context with the other common scanner parameters affecting OPE.

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The ecomony scale of return for semiconductor wafers can be attributed to 2 factors i.e.1) number of systems that is crammed onto a wafer and 2) substitution of precious metal (Au) to other material for the wafer backmetal. Any of these 2 changes will be a major challenge to semiconductor wafer dicing yield. Crack die with a random order is a great myth to be dicovered. In this study, Moire Techniques is being adopted to perform the upfront analysis on the crack die to minimize the yield loss during dicing process. In this study we focus and to corellate 3 different wafers with different size (5", 6" and 8") and backmetal (bare silicon, Au and AuX). The effect of the backside metallization to the die strength has been numerically and experimentally investigated. These results obtained is being made to optimise the dicing method to obtain a homogenous stresses across the wafer.