The use of experimental development rate information is used to demonstrate various deficiencies in the dissolution rate equations commonly employed in commercial lithography simulation programs. An improved version of the Notch dissolution rate equation, incorporating one new parameter, is proposed, which addresses the observed deficiencies. Simulation work comparing the new equation to the standard Notch model reveals significant differences in process window and exposure margin, yet negligible changes in feature profile and iso-dense bias at "best" focus and exposure.

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As design rules shrink, there is an increase in the complexity. OPC/RET have been facilitating unprecedented yield at k 1 factors, they increase the mask complexity and production cost, and can introduce yield-detracting errors. Currently OPC modeling techniques are based on extensive CD-SEM measurements which are limited to one dimensional structures or specific shape structures e.g. contact holes. As a result the measured information is not representing the whole spatial 2D change in the process. Therefore the most common errors are found in the OPC design itself and in the resulting patterning robustness across the process window. A new methodology for OPC model creation and verification is to extract contours from complex test structures which beside the CD values contain further information about e.g. various proximities.In this work we use 2D contour profiles extracted automatically by the CD-SEM over varying focus and exposure conditions. We will show that the measurement sensitivity and uncertainty of that algorithm through the whole process window fulfills the requirements of the ITRS with respect to CD-SEM metrology tools. This will be done on various test structures normally being used for OPC model generation and OPC stability monitoring. Furthermore a study on systematic influences on the quality of the extracted contours has been started. This study includes the evaluation of various parameters which are considered as possible contributors to the uncertainty of the edge contour extraction. As one of the parameters we identified the pixel size of the SEM images. Furthermore, a new metric for calculating repeatability and reproducibility determination for 2D contour extraction algorithms will be presented. By applying this contour extraction based methodology to different CD-SEM tool generations the influence of SEM beam resolution to the quality of the contours will be evaluated.

Optical lithography simulation plays a decisive role in the development of technology for the manufacturing process of semiconductor devices. Its role in reticle inspection has only recently gained more attention. Filters determining which defects need repair and which ones can be ignored help set up the filter classes in inspection systems. These calculations are performed offline. In an effort to increase the accuracy of inspection it would be desirable to place the decision level as close to the actual process as possible. Therefore, an inspection system based on aerial images is a step in this direction. In addition, an optical simulator calculates from the aerial image the resist image. To do so very fast resist image models are needed (see figure 7) . Quick models so far were restricted by accuracy and speed. In this paper a new very fast model will be presented that allows calculation of large areas suitable for inspection purposes. Finally a "virtual inspection" system will be presented pinpointing at weak spots in the layout.In an effort to calculate larger areas of the resist in less time we had to take completely new approaches[1]. They led us to analytical descriptions of the image transfer into the resist. Within these descriptions we begin in this first paper to investigate an approach based on the propagation of a top aerial image into the resist. The aerial image may come from calculations, as in the present article, or as well from measurements.The purpose of this article is to demonstrate the performance of the Fast Resist Model with respect to accuracy and time consumption. The limits of the current model are equally described.

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