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The selective amorphization of SiGe in Si/SiGe nanostructures via a 1 MeV Si+ implant was investigated, resulting in single-crystal Si nanowires (NWs) and quantum dots (QDs) encapsulated in amorphous SiGe fins and pillars, respectively. The Si NWs and QDs are formed during high-temperature dry oxidation of single-crystal Si/SiGe heterostructure fins and pillars, during which Ge diffuses along the nanostructure sidewalls and encapsulates the Si layers. The fins and pillars were then subjected to a 3 × 1015 ions/cm2 1 MeV Si+ implant, resulting in the amorphization of SiGe, while leaving the encapsulated Si crystalline for larger, 65-nm wide NWs and QDs. Interestingly, the 26-nm diameter Si QDs amorphize, while the 28-nm wide NWs remain crystalline during the same high energy ion implant. This result suggests that the Si/SiGe pillars have a lower threshold for Si-induced amorphization compared to their Si/SiGe fin counterparts. However, Monte Carlo simulations of ion implantation into the Si/SiGe nanostructures reveal similar predicted levels of displacements per cm3. Molecular dynamics simulations suggest that the total stress magnitude in Si QDs encapsulated in crystalline SiGe is higher than the total stress magnitude in Si NWs, which may lead to greater crystalline instability in the QDs during ion implant. The potential lower amorphization threshold of QDs compared to NWs is of special importance to applications that require robust QD devices in a variety of radiation environments. [ABSTRACT FROM AUTHOR]

The issue of connectivity in roaded landscapes is a controversial one. Conservationists argue for significant expenditures on wildlife-friendly highway designs, while opponents fight against such spending. A recent study evaluating wildlife use of underpasses in the Adirondack region of New York ran headlong into this controversy, inadvertently fueling a debate about the general efficacy of wildlife underpasses through misleading coverage of research results in the popular press. This poster will detail the road traveled by this project: from conception through implementation, to the publicizing of results and the subsequent media fallout, and will conclude with the steps taken to clarify the study conclusions and lessons learned about publicizing science that is of public and political interest. Because the proposed construction of the “Rooftop Highway” between Interstates 81 and 87 could effectively complete the isolation of the 24,000km2 Adirondack Park, measures to mitigate negative impacts on wildlife are a priority in the region. The Wildlife Conservation Society (WCS) and the New York State Museum (NYSM) recently partnered on a small research project investigating the extent to which underpasses and culverts constructed under a nearby Adirondack highway (I-87) were utilized by wildlife. Although these structures were not explicitly designed for wildlife, they might still function as animal passageways. Interviews with NY DOT and other agency personnel strongly encouraged implementation of a study of this nature to help inform the design of new wildlife crossings. During a six-week period in spring 2002, we monitored 19 culverts and underpasses of various types along a 141-km stretch of I-87 using camera traps and supplemental footprint tracking. The results of this study, published in spring 2003 in the Adirondack Journal of Environmental Studies, made it clear that culverts along I-87 benefited humans, but were rarely utilized by wildlife, pointing to the low conservation value of unplanned culverts for large Adirondack wildlife. A secondary message was that wildlife passages under future roads and highways should be designed to curb human use of such passages. A draft press release by the authors accurately summarizing the study results was unintentionally distorted in institutional press releases from WCS and NYSM media offices. Local newspapers that picked up the story generally interviewed the authors and offered accurate coverage that focused on the costs and benefits of the proposed “Rooftop Highway.” This perspective was lost, however, in small pieces printed in the Washington Post and the New York Times. These stories distorted the study’s findings that almost no animals used the small I-87 culverts, by incorrectly claiming that wildlife underpasses universally do not work for wildlife. The lack of interviews for these national stories further deprived the authors of an opportunity to clarify this point. While the full impact of the Washington Post article is difficult to judge, it has apparently been cited by some officials and decision-makers as evidence against the effectiveness of wildlife underpasses. This misrepresentation of our results was a blow to all those working to improve connectivity in roaded landscapes, including the authors. We describe the steps taken by the scientists and institutions involved in this study to move constructively forward from this point. We also draw attention to the political climate surrounding this particular issue and a large volume of email exchanges, both of which served to greatly magnify the impact of this relatively minor study.