Resists for optical electron beam, and x-ray lithographies that operate on the principles of chemical amplification are entering into widespread use in laboratories. They offer an attractive alternative to conventional positive Novolac photoresists and we may soon see similar use in manufacturing environments. One class of resists within this family is based on acid-hardening chemistry. We have characterized one such resist (Shipley ECX-1033) for illumination by excimer laser deep ultraviolet sources and also by x-ray radiation. A matrix of post exposure bake (PEB) conditions and development conditions was used to examine resist sensitivity and contrast. For all exposure sources we found that contrast is independent of PEB processing and that sensitivity obeys an Arrhenius dependence. Contrast increases with increasing development time while exposed resist loss is minor. A simple kinetic model was developed to explain the observed variations of apparent resist sensitivity with PEB time and temperature. The generality of this model suggests that it is widely applicable to other chemical amplification resists that require a post exposure bake. Together with aerial image calculations for different light sources, the model makes it possible to predict the dependence of line width on PEE conditions. In other words, we can anticipate the PEB process control required to achieve a specified critical dimension control. Electrical linewidth measurements of submicron features and their temperature dependence are compared with the predictions of the model.
We can all agree that institutions matter, though as to which institutions matter most, and how much any of them matter, the matter is, paraphrasing Douglass North's words at the Nobel podium, unresolved after seven decades of immense effort. We suggest that the obstacle to progress is the paradigm of the New Institutional Economics itself. In this paper, we propose a new theory that is: grounded in institutions as coevolving sources of economic growth rather than as rules constraining growth; and deployed in dynamical systems theory rather than game theory. We show that with our approach some long-standing problems are resolved, in particular, the paradoxical and perplexingly pervasive influence of informal constraints on the long-run character of economies.
Boron nitride membranes (produced through chemical vapor deposition of diborane and ammonia) have been exposed to synchrotron radiation and have showed severe degradation in optical properties after absorbing doses on the order of 200kJ /cm3.Damage kinetics are described as well as measurements made to identify the damage mechanism.Preliminary results on associated mechanical damage are also presented. Boron nitride membranes (produced through the pyrolysis of borazine), silicon nitride and silicon membranes exposed and tested in the same manner showed no such degradation.
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