Fabrication of Sub-300nm Fins at RIT by SADP

The goal of fabricating sub-300 nm fins with the implementation of self-aligned double patterning (SADP) at Rochester Institute of Technology’s (RIT’s) Semiconductor & Microsystems Fabrication Laboratory (SMFL) was not realized completely. An energy dose meander was completed in order to qualify a new resist being used with the fabrication process that Christopher O’Connell developed for his graduate thesis. Manual spin coating of Spin-on-Carbon (SOC), bottom antireflective coating (BARC), and photoresist were all qualified. A 2:1 ratio of AZ MiR 701 photoresist to PGMEA was used to thin the resist for implementation of a 300 nm coat. Low pressure chemical vapor deposition (LPCVD) of silicon nitride as a spacer material was qualified with a ~6.4 nm/s deposition rate and a film etch rate of ~0.3 nm/s. Oxide deposition by in Applied Materials’ P5000 TEOS chamber was qualified with an ~8.8 nm/s deposition rate and a ~3.2 nm/s etch rate in the magnetically enhanced reactive ion etch (MERIE) etch chamber of the same P5000 tool cluster. In the RIE chamber, an etch rate of ~0.8 nm/s was qualified for the BARC layer. Ultimately, the oxide mandrels appeared to lack essential vertical sidewalls

Canopy Gap Characteristics of an Oak-Beech-Maple Old-Growth Forest in Northeastern Ohio

Author Institution: School of Natural Resources, The Ohio State UniversityForests are gap-driven systems as openings within the tree canopy directly influence species composition, structure, and regeneration. Most gap studies have occurred in small, mesic, old-growth remnants. This study sought to further the understanding of gap characteristics by examining gaps in one of Ohio's largest old-growth forests, which has wet-mesic site conditions and high species diversity. A modification of the methodology recommended by Runkle (1992) was used to obtain data on gap characteristics. An important portion (17.7%) of this old-growth forest was in gaps. Most of the gaps sampled were large (100-400 m2), and multiple-tree gaps were significantly larger than single-tree gaps. Tip-up and basal shear of a canopy tree were the primary means by which a gap was created (origin type). These findings differ from some other similar gap studies, and the contrasts may be due to the advanced age and particular species composition of this forest, the poor soil drainage conditions, and the large size and stressed condition of the overstory trees

University of Maine Proposal for Joining the NSF Center for Advanced Forestry Systems

University of Maine (UM) is planning to join the existing multi-university Industry/University Cooperative Research Center (I/UCRC) entitled The Center for Advanced Forestry Systems (CAFS) which was established in 2007 with four member institutions: North Carolina State University (lead university), Oregon State University, Purdue University and Virginia Tech. The primary focus of the proposed research site within CAFS will be modeling the productivity of managed natural forests. This research focus will be addressed at multiple scales ranging from the individual tree to the regional forest. UM has a long history of applied research in the management of naturally regenerated forests as well as a strong relationship with the forest products industry. The proposed activities at UM will augment current CAFS projects, and will more fully address the needs for scientific and technological advances for enhancing the competitiveness of the US forestry sector. The effort at UM has the potential to improve the competitiveness of the forest products industry by solving key problems using applied research and enhanced institutional collaboration. The broader scientific community will benefit through refereed publications and presentations at scientific meetings that focus on key nationwide research questions. Enhanced graduate student research opportunities will increase the number of trained professionals able to address these future forest resource challenges. UM also plans to address employee and student diversity issues

Examining approaches for modeling individual tree growth response to thinning in Norway spruce

Using periodic measurements from permanent plots in non-thinned and thinned Norway spruce (Picea abies (L.) H. Karst.) stands in Norway, individual-tree growth models were developed to predict annual diameter increment, height increment, and height to crown base increment. Based on long-term data across a range of thinning regimes and stand conditions, alternative approaches for modeling response to treatment were assessed. Dynamic thinning response functions in the form of multiplicative modifiers that predict no effect at the time of thinning, a rapid increase followed by an early maximum before the effect gradually declines to zero could not be fitted to initially derived baseline models without thinning related predictors. However, alternative approaches were used and found to perform well. Specifically, indicator variables representing varying time periods after thinning were statistically significant and behaved in a robust manner as well as consistent with general expectations. In addition, they improved overall prediction accuracy when incorporated as fixed effects into the baseline models for diameter and height to crown base increment. Further, more simply, including exponentially decreasing multiplicative thinning response functions improved prediction accuracy for height increment and height to crown base increment. Irrespective of studied attribute and modelling approach, improvement in performance of these extended models was relatively limited when compared to the corresponding baseline models and more pronounced in trees from thinned stands. We conclude that the largely varying and often multi-year measurement intervals of the periodic data used in this study likely prevented the development of more sophisticated thinning response functions. However, based on the evaluation of the final models’ overall performance such complex response functions may not to be necessary to reliably predict individual tree growth after thinning for certain conditions or species, which should be further considered in future analyses of similar nature.publishedVersio

Forest-based Opportunities for Resilient Economy, Sustainability, and Technology (Maine-FOREST) EPSCoR Planning Grant: Knowledge-Sharing Findings, Discussion of Themes, and Collaboration Opportunities

In late November 2022 through early January 2023 the Maine Planning Grant team for the National Science Foundation (NSF) Established Program to Stimulate Competitive Research (EPSCoR) conducted knowledge-sharing conversations with 11 leaders in the field (subject matter experts) who spoke about forest industry opportunities, workforce education, research, conservation, policy making and Indigenous engagement. The conversations were anonymous, and each lasted 45 minutes to an hour. Overall, experts were tremendously enthusiastic about the opportunity ahead, and collaborating with the EPSCoR team

Center for Research on Sustainable Forests 2019 Annual Report

The Center for Research on Sustainable Forests (CRSF) and Cooperative Forestry Research Unit (CFRU) continued to move forward on multiple fronts with a particularly productive and rewarding FY18-19. This included leadership on several key new initiatives such as the Forest Climate Change Initiative (FCCI), Intelligent GeoSolutions (IGS), and a funded National Science Foundation (NSF) Track 2 EPSCoR grant (INSPIRES). This is in addition to ongoing leadership and support for important CRSF programs such as NSF’s Center for Advanced Forestry Systems (CAFS), the Northeastern Research Cooperative (NSRC), and FOR/Maine. In short, CRSF is on a bold upward trajectory that highlights its relevance and solid leadership with a rather bright future

Managing the middle ground: forests in the transition zone between cities and remote areas

In many parts of the world there are extensive landscapes where forests and people strongly intermingle, notably in the suburbs and exurbs of cities. This landscape of transitional forest generally receives limited attention from policy makers and researchers who tend to be rooted in traditions centered on either urban planning or management of natural resources in rural areas. The transitional forest is on the periphery of both perspectives, but it is a large area that provides numerous important values (biodiversity, ecosystem function, forest products, and amenities) to the people that live in them and their neighboring cities. Here we argue for increased attention to transitional forests, identify major challenges, and suggest changes to planning and management practices needed to ensure that the values of these forests are sustained

Center for Research on Sustainable Forests 2020 Annual Report

FY20 saw exciting changes in CRSF with several new initiatives launched, while progress continues on many other ongoing efforts. In particular, FY20 saw the start of two National Science Foundation funded and CRSF-led research projects. The first is the INSPIRES project, a multi-year research collaboration between Maine, New Hampshire, and Vermont focused on harnessing Big Data to better understand and forecast the region’s forest given current as well as future uncertainties. The other effort was a successful Phase 3 reboot of the National Science Foundation Industry-University Collaborative Research Center, Center for Advanced Forestry System (CAFS), for which I have served as Director since 2016. CAFS provides direct connections among several additional universities across the United States, including North Carolina State University, Oregon State University, Purdue University, University of Georgia, University of Idaho, and University of Washington, as well as to forest industry partners. Phase 3 of CAFS will be a five-year effort and, I hope, will lead to the successful graduation of the IUCRC

Data Frontiers : The Intersection of Emerging Technologies and Maine\u27s Heritage Industries

On June 13, 2023, a diverse group of educators and professionals from across the state of Maine gathered at the University of Maine\u27s Portland Gateway to discuss the field of Al technology and the related areas of data science and informatics. These topics were interwoven with the future of Maine\u27s natural forest resources and the industries that have developed around them. Technology in the digital landscape is ever-changing, and recent developments in artificial intelligence (Al) show potential to benefit industries of all kinds. With recognition of the historic contributions of these heritage industries also comes awareness of the challenges they face in an uncertain future. Climate change presents a real threat to the world that will cause once-familiar industrial landscapes to shift into new territory. As more people around the globe find themselves in need of different sources of food and forest products, more eyes will turn to the abundant resources in Maine. While this presents significant economic opportunity for the people of Maine, it also represents a potential disruption to the sustainable use of these resources. Overcoming these challenges will require a robust, well-trained workforce. As will be detailed later in this report, many of Maine\u27s companies are facing difficulties in finding employees with appropriate skills. Attendees at the Portland Gateway meeting highlighted a multitude of obstacles they are facing in recruiting high tech employees, indicating that barriers exist

Alterations in Douglas-fir crown structure, morphology, and dynamics imposed by the Swiss needle cast disease in the Oregon Coast Range

Plants respond to defoliation in many different and complex ways, depending on their growth habit and form as well as the extent and duration of the defoliation. Tree crowns have been shown to be quite sensitive to disturbances such as defoliation, however quantitative relationships have rarely been developed, making the true biological meaning of crown condition assessments quite difficult to decipher. The sudden emergence of Swiss needle cast (SNC) in the Oregon Coast Range prompted investigation of the response of Douglas-fir crown structure, crown morphology, and foliage dynamics to extended defoliation. Using data from permanent plots and 82 destructively sampled trees, hypotheses regarding the response of trees to defoliation were tested with linear and nonlinear models. Responses of crowns were investigated at multiple levels including the needle, branch, tree, and stand scales. At the individual-needle level, SNC has resulted in foliage that is smaller in length, width, and projected area; lower in dry mass; and higher in specific leaf area. The disease has influenced the foliage age structure by increasing the proportion in the younger age classes with greater SNC severity. The disease has also resulted in crowns that have a greater proportion of their current and 1-year-old needles located higher in the crown than Abstract approved Douglas A. Maguire normal, while the 2-, 3- and 4-year-old needles are shifted towards the crown base relative to healthy trees. At the branch-level, the disease has modified growth patterns as well as dry matter production and allocation. The number of secondary lateral branches on a primary branch declined in response to the disease, as did the foliated branch length and diameter for a given position in the crown. The ratio of branch length to branch diameter, however, increased with disease severity, which suggests altered elongation patterns. Branches in the lower portion of the heavily diseased crowns were elongating faster than normal, while elongation of branches in the mid-crown was slower. Elongation of branches in the upper crown was unaffected. The disease significantly reduced branch foliage dry matter and area for a given position in the crown and diameter. Branches, however, allocated more dry matter to higher order branches, but less dry matter to primary branch elongation. At the tree-level, the disease has led to crowns that are shorter than normal, while the largest measured standing width remains unaffected. Crown radii and maximum branch diameter profiles suggested that changes within the crown might be occurring at different levels due to variations in SNC damage within the crown. The number of primary interwhorl branches decreased with greater disease severity. SNC also significantly reduced total foliage and branchwood dry matter. Overall, the vertical distribution of foliage dry matter was less skewed and more uniform with increased disease severity. At the stand-level, SNC has significantly increased crown recession rates, woody litterfall, the specific leaf area of the litter, and growth efficiency. The disease caused a decline in foliage litterfall rates as well as leaf area index. In addition, the seasonal distribution of foliage litterfall was altered, with a greater amount occurring in the summer than normal. Crown condition, as assessed by foliage retention and the crown sparseness index, varied with SNC and other site factors. Within-tree variability of foliage retention was significantly higher than between-tree or between-plot variability. Although assessments of foliage retention were found to be highly variable, the sample size required to attain a sufficiently precise estimate for a given tree and stand are lower than the sample sizes currently being collected. The crown sparseness index was found to be significantly less variable than foliage retention and was primarily influenced by stand factors such as age and stand density. Defoliation caused significant changes at the individual needle, branch, tree, and stand levels, complicating efforts to accurately predict growth responses to defoliation. This detailed analysis of crown and foliage dynamics helps to establish links among current SNC studies. For example, growth losses associated with SNC are due to the reduction of foliage area, but also to changes in the size and vertical distribution of the needles. In addition, crown assessment indices such as foliage retention and crown length to sapwood area ratio represent different aspects of crown condition. Crown attributes are sensitive to the direct and indirect effects of SNC, which have important implications for tree growth and stand management. Important direct effects include the premature loss of foliage, while important indirect effects of SNC include changes in the within-crown light environment. Integrating measures of crown condition into forest models, therefore, represents an important step towards incorporating physiological-mechanisms into models for predicting growth responses to environmental changes such as tree disease and for understanding the complex responses of tree morphology and growth