Reduced basis method for computational lithography

A bottleneck for computational lithography and optical metrology are long computational times for near field simulations. For design, optimization, and inverse scatterometry usually the same basic layout has to be simulated multiple times for different values of geometrical parameters. The reduced basis method allows to split up the solution process of a parameterized model into an expensive offline and a cheap online part. After constructing the reduced basis offline, the reduced model can be solved online very fast in the order of seconds or below. Error estimators assure the reliability of the reduced basis solution and are used for self adaptive construction of the reduced system. We explain the idea of reduced basis and use the finite element solver JCMsuite constructing the reduced basis system. We present a 3D optimization application from optical proximity correction (OPC).Comment: BACUS Photomask Technology 200

Should We Drill in the Arctic National Wildlife Refuge? An Economic Perspective

This paper provides model-based estimates of the value of oil in Alaska's Arctic National Wildlife Refuge (ANWR). The best estimate of economically recoverable oil in the federal portion of ANWR is 7.06 billion barrels of oil, a quantity roughly equal to US consumption in 2005. The oil is worth $374 billion ($2005), but would cost $123 billion to extract and bring to market. The difference,$251 billion, would generate social benefits through industry rents of $90 billion as well as state and federal tax revenues of$37 billion and $124 billion, respectively. A contribution of the paper is the decomposition of the benefits between industry rents and tax revenue for a range of price and quantity scenarios. But drilling and development in ANWR would also bring about environmental costs. These costs would consist largely of lost nonuse values for the protected status of ANWR's natural environment. Rather than estimate these costs and conduct a benefit-cost analysis, we calculate the costs that would generate a breakeven result. We find that the average breakeven willingness to accept compensation to allow drilling in ANWR ranges from$582 to $1,782 per person, with a mean estimate of$1,141.

Image denoising with multi-layer perceptrons, part 1: comparison with existing algorithms and with bounds

Image denoising can be described as the problem of mapping from a noisy image to a noise-free image. The best currently available denoising methods approximate this mapping with cleverly engineered algorithms. In this work we attempt to learn this mapping directly with plain multi layer perceptrons (MLP) applied to image patches. We will show that by training on large image databases we are able to outperform the current state-of-the-art image denoising methods. In addition, our method achieves results that are superior to one type of theoretical bound and goes a large way toward closing the gap with a second type of theoretical bound. Our approach is easily adapted to less extensively studied types of noise, such as mixed Poisson-Gaussian noise, JPEG artifacts, salt-and-pepper noise and noise resembling stripes, for which we achieve excellent results as well. We will show that combining a block-matching procedure with MLPs can further improve the results on certain images. In a second paper, we detail the training trade-offs and the inner mechanisms of our MLPs

Rigorous Simulations of 3D Patterns on Extreme Ultraviolet Lithography Masks

Simulations of light scattering off an extreme ultraviolet lithography mask with a 2D-periodic absorber pattern are presented. In a detailed convergence study it is shown that accurate results can be attained for relatively large 3D computational domains and in the presence of sidewall-angles and corner-roundings.Comment: SPIE Europe Optical Metrology, Conference Proceeding