27 May 2009 Error-budget paradigms and laser mask pattern generator evolution
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Proceedings Volume 7470, 25th European Mask and Lithography Conference; 74700W (2009) https://doi.org/10.1117/12.835194
Event: 25th European Mask and Lithography Conference, 2009, Dresden, Germany
The evolution of the ALTA(R) series of laser mask pattern generators has increased the relative contribution of intensity errors on critical-dimension (CD) control to those from placement errors. This paradigm shift has driven a change in rasterization strategy wherein aerial image sharpness is improved at the cost of a slight decrease in the averaging of column-to-column placement errors. Print performance evaluation using small-area CD test patterns show improvements in stripe-axis local CD uniformity (CDU) 3σ values of 15-25% using the new strategy, and systematic brush-error contributions were reduced by 50%. The increased importance of intensity errors, coupled with the improvement of ALTA system performance, has also made the mask-blank and process-induced errors a more significant part of the overall error budget. A simple model based on two components, a pattern-invariant footprint and one related to the exposure density ρ(x, y), is shown to describe adequately the errors induced by these sources. The first component is modeled by a fourth-order, two-dimensional polynomial, whereas the second is modeled as a convolution of ρ(x, y) with one or more Gaussian kernels. Implementation of this model on the ALTA 4700 system shows improvements in global CDU of 50%.
© (2009) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
H. Christopher Hamaker, H. Christopher Hamaker, Matthew J. Jolley, Matthew J. Jolley, Andrew D. Berwick, Andrew D. Berwick, } "Error-budget paradigms and laser mask pattern generator evolution", Proc. SPIE 7470, 25th European Mask and Lithography Conference, 74700W (27 May 2009); doi: 10.1117/12.835194; https://doi.org/10.1117/12.835194

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