of the Bureau of Reclamation provided scientific support and managed lidar data acquisition.

The New York State Department of Health and individual county health departments provided information on numerous contamination events that were in karst areas. In a similar fashion, the New York State soil and water conservation districts provided data to assist in identifying where contamination issues in karst has occurred across the State.

The universality of a single percolation field scaling law to the tetramethylammonium hydroxide dissolution of derivatized novolac and poly(4-vinylphenol) polymers was investigated. According to this hypothesis, the dissolution ofphenolic polymers occurs through a percolative mechanism resulting from the diffusion of base along nascent channels formed by the spatial proximity of phenolic hydroxyl groups (presumably diffusion of the cation is rate limiting). Dissolution inhibition results from the the removal of sites from the percolation field. In this study, the polymers were derivatized with increasing amounts of either 2,1,5-diazonaphthoquinone groups or methylsuiphonyl ester groups and the dissolution rates of the films were measured. While our experimental data supported adherence to a percolation law (p =the scaled amount of free hydroxyl sites remaining on the polymer), Rate = Rate0 (ppc)t , we did not find that a single exponent of t = 2 universally described the dissolution behavior. Rather, our data indicated that t varied with different systems, with values of t greater than 5 being observed. These results are explained in terms of multiple simultaneously operant mechanisms of dissolution creating an environment where multiple percolation can occur. The relative shielding effects of the blocking groups are also compared.A computer simulation of Reiser's percolation model was constructed to gain a better understanding of the dissolution kinetics. We found that the function which governs the probability of transfer from a phenolate site to a hydroxyl site needed to be relaxed in order to allow a greater likelihood of transfer, particularly when the site separation distance exceeded 5 A. The simulated values of xc decreased as either the difficulty of intersite transfer was increased, or as the shielding effect per blocking group was increased.

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Negative tone chemically amplified i-line resists possess several advantages compared to conventional DNQ-Novolak resists. These advantages include excellent lithographic performance at a fast, tunable photospeed, high transparency, high thermal flow stability and improved etch resistance. An additional advantage of using negative resists for logic applications is that the difference in CD for various features (US, Iso L, CH, Trenches, Posts) at a fixed dose is small relative to conventional positive resists1, allowing the maximum potential for printing these features simultaneously.ULTRA_iTM 300/310 are negative acting i-line photoresists with excellent lithographic performance optimized for 90°C PAB/l 10°C PEB processing. These materials offer extremely high resolution capability without microbridging, fast photospeed, and a robust post exposure delay process window with minimal film loss over a period of hours. These resists exhibit extremely low PEB temperature sensitivity (2-3 nm/°C) which is expected to reduce across chip linewidth variation (ACLW). Low optical density permits thick film applications producing high aspect ratio relief images with vertical profiles. Furthermore, addition of appropriate dyes permits resists to be designed for lift-off applications with controlled retrograde profiles.