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Extreme ultraviolet (EUV) lithography is one of the most promising printing techniques for high-volume semiconductor manufacturing at the 14-nm half-pitch device node and beyond. However, key challenges around EUV photoresist materials, such as the exposure-dose sensitivity or the line-width roughness, continue to impede its full adoption into industrial nanofab facilities. Metrology tools are required to address these challenges by helping to assess the impact of the EUV materials' properties and processing conditions along different steps of the nanofabrication process. We apply the resonant soft x-ray scattering (RSoXS) technique to gain insights into the structure of patterned EUV resists before the development step takes place. By using energies around the carbon K-edge to take advantage of small differences in chemistry, the electronic density contrast between the exposed and unexposed regions of the resists could be enhanced in order to image the patterns with subnanometer precision. Critical-dimension grazing-incidence small-angle x-ray scattering is then performed at energies where the contrast is maximized, enabling the reconstruction of the three-dimensional shape of the latent image. We demonstrate the potential of RSoXS to provide a high-resolution height-sensitive profile of patterned EUV resists, which will help in quantifying the evolution of critical features, such as the line-edge roughness, at a key step of the nanofabrication process.

Extreme ultraviolet lithography is one of the most promising printing techniques for high volume semiconductor manufacturing at the 14 nm half-pitch device node and beyond. However, key challenges around EUV photoresist materials such as the exposure-dose sensitivity or the line-width roughness continue to impede the full adoption into industrial nanofab facilities. New metrology tools are required to address these challenges by helping to determine the impact of the EUV materials' properties and processing conditions on the roughness through the different step of the process. Here, we apply the resonant soft x-ray scattering (RSOXS) technique to gain insights into the structure of patterned EUV resists before the development step takes place. By using energies around the carbon absorption edge to take advantage of small differences in chemistry, the electronic density contrast between the exposed and unexposed regions of the resists could be enhanced in order to image the patterns with sub-nm precision. Critical-dimension grazing incidence small-angle X-ray scattering (CDGISAXS) was then performed at energies where the contrast was maximized, enabling the reconstruction of the 3D shape of the latent image. This demonstrates the potential of RSOXS to provide a high-resolution heightsensitive profile of patterned EUV resists, which will help to quantify the evolution of critical features, such as the line edge roughness, at each step of the nanofabrication process.

Aim: To examine heterogeneity in outcome at 12 months following 8 weeks of treatment for smoking cessation with bupropion sustained-release (SR) 150 or 300 mg/day combined with behavioural counselling.Design, Setting, Participants: Smokers were recruited from a large healthcare system and then randomized to receive either bupropion SR 150 mg/day (n = 763) or 300 mg/day (n = 761) taken for 8 weeks in combination with either proactive telephone counselling or a tailored mail approach.Measurements and Findings: A comprehensive set of relevant individual pretreatment and treatment characteristics was included in the analysis. Smoking outcome at 12 months was defined as point-prevalence of any regular self-reported smoking within the 7 days prior to follow-up contact. Classification and regression tree analysis identified subgroups that varied with respect to likelihood of being nonsmokers at 12 months. Seven subgroups were identified among those receiving bupropion SR 150 mg/day (proportion of nonsmokers at 12 months ranged from 13.7% to 43.5%) and eight subgroups among those receiving bupropion SR 300 mg/day (proportion of nonsmokers at 12 months ranged from 9.6% to 51.7%). In the 150-mg/day group, those with the lowest rate reported no previous quit attempt of 1 month or more in duration while those with the highest rate all reported previous quit attempts of 1 month or longer. In the 300 mg/day group, those with the lowest rate had very high levels of dependence while those with the highest rate were more highly educated and smoked at a lower level. Across all subgroups, cost per 12-month quitter ranged from a low of USD302 to a high of USD2,502.Conclusions: These results indicate the presence of a substantial amount of variation in outcome following treatment with both dosages of bupropion SR, with substantial cost consequences. Variation in outcome could be reduced by providing treatments tailored to subgroups of individuals who are at exceptionally high risk for smoking following a quit attempt. [ABSTRACT FROM AUTHOR]

Purpose: To describe change in Minnesota's QUITPLAN helpline operations following provision of nicotine replacement therapy (NRT) to multisession counseling enrollees.Methods: NRT access began September 2002. Call volume is reported from September 2001 to May 2003 (pre-NRT = 2734, post-NRT = 12,536). A survey administered at 2 weeks assesses self-reported connection to services (response rate 80%, n = 538/670, pre-NRT vs. 67%, n = 400/595, post-NRT, p < .001).Results: Provision of NRT was followed by an increase in call volume (439 +/- 229 calls/month January through May pre-NRT vs. 1292 +/- 308 calls/month January through May post-NRT, p = .001). Enrollment in multisession counseling increased (17.4% pre-NRT vs. 75.3% post-NRT, p < .001). Among survey respondents, connection to services was not changed (83.8% pre-NRT vs. 88.0% post-NRT, p = .072). At 2 weeks, more respondents who enrolled in multisession counseling reported having a follow-up call scheduled (43.9% pre-NRT vs. 64.1% post-NRT, p = .001).Conclusions: This is an observational study. Providing NRT as part of a statewide helpline may increase recruitment and encourage callers to enroll in multisession counseling. [ABSTRACT FROM AUTHOR]

Studying polymer micelle structure and loading dynamics under environmental conditions is critical for nanocarrier applications but challenging due to a lack of in situ nanoprobes. Here, the structure and loading of amphiphilic polyelectrolyte copolymer micelles, formed by 2-acrylamido-2-methylpropanesulfonic acid (AMPS) and n -dodecyl acrylamide (DDAM), were investigated using a multimodal approach centered around in situ resonant soft X-ray scattering (RSoXS). We observe aqueous micelles formed from polymers of wide-ranging molecular weights and aqueous concentrations. Despite no measurable critical micelle concentration (CMC), structural analyses point toward multimeric structures for most molecular weights, with the lowest molecular weight micelles containing mixed coronas and forming loose micelle clusters that enhance hydrocarbon uptake. The sizes of the micelle substructures are independent of both the concentration and molecular weight. Combining these results with a measured molecular weight-invariant surface charge and zeta potential strengthens the link between the nanoparticle size and ionic charge in solution that governs the polysoap micelle structure. Such control would be critical for nanocarrier applications, such as drug delivery and water remediation.

Although solvent additives are used to optimize device performance in many novel non-fullerene acceptor (NFA) organic solar cells (OSCs), the effect of processing additives on OSC structures and functionalities can be difficult to predict. Here, two polymer-NFA OSCs with highly sensitive device performance and morphology to the most prevalent solvent additive chloronaphthalene (CN) are presented. Devices with 1% CN additive are found to nearly double device efficiencies to 10%. However, additive concentrations even slightly above optimum significantly hinder device performance due to formation of undesirable morphologies. A comprehensive analysis of device nanostructure shows that CN is critical to increasing crystallinity and optimizing phase separation up to the optimal concentration for suppressing charge recombination and maximizing performance. Here, domain purity and crystallinity are highly correlated with photocurrent and fill factors. However, this effect is in competition with uncontrolled crystallization of NFAs that occur at CN concentrations slightly above optimal. This study highlights how slight variations of solvent additives can impart detrimental effects to morphology and device performance of NFA OSCs. Therefore, successful scale-up processing of NFA-based OSCs will require extreme formulation control, a tuned NFA structure that resists runaway crystallization, or alternative methods such as additive-free fabrication., (© 2022 Wiley-VCH GmbH.)

Commercialization and scale-up of organic solar cells (OSCs) using industrial solution printing require maintaining maximum performance at active-layer thicknesses >400 nm─a characteristic still not generally achieved in non-fullerene acceptor OSCs. NT812/PC71BM is a rare system, whose performance increases up to these thicknesses due to highly suppressed charge recombination relative to the classic Langevin model. The suppression in this system, however, uniquely depends on device processing, pointing toward the role of nanomorphology. We investigate the morphological origins of this suppressed recombination by combining results from a suite of X-ray techniques. We are surprised to find that while all investigated devices are composed of pure, similarly aggregated nanodomains, Langevin reduction factors can still be tuned from ∼2 to >1000. This indicates that pure aggregated phases are insufficient for non-Langevin (reduced) recombination. Instead, we find that large well-ordered conduits and, in particular, sharp interfaces between domains appear to help to keep opposite charges separated and percolation pathways clear for enhanced charge collection in thick active layers. To our knowledge, this is the first quantitative study to isolate the donor/acceptor interfacial width correlated with non-Langevin charge recombination. This new structure-property relationship will be key to successful commercialization of printed OSCs at scale.

Self-assembled molecular nanostructures embody an enormous potential for new technologies, therapeutics, and understanding of molecular biofunctions. Their structure and function are dependent on local environments, necessitating in-situ/operando investigations for the biggest leaps in discovery and design. However, the most advanced of such investigations involve laborious labeling methods that can disrupt behavior or are not fast enough to capture stimuli-responsive phenomena. We utilize X-rays resonant with molecular bonds to demonstrate an in-situ nanoprobe that eliminates the need for labels and enables data collection times within seconds. Our analytical spectral model quantifies the structure, molecular composition, and dynamics of a copolymer micelle drug delivery platform using resonant soft X-rays. We additionally apply this technique to a hydrocarbon sequestrating polysoap micelle and discover that the critical organic-capturing domain does not coalesce upon aggregation but retains distinct single-molecule cores. This characteristic promotes its efficiency of hydrocarbon sequestration for applications like oil spill remediation and drug delivery. Such a technique enables operando, chemically sensitive investigations of any aqueous molecular nanostructure, label-free.

We present the design and performance of a polarized resonant soft x-ray scattering (RSoXS) station for soft matter characterization built by the national institute of standards and technology at the national synchrotron light source-II (NSLS-II). The RSoXS station is located within the spectroscopy soft and tender beamline suite at NSLS-II located in Brookhaven national laboratory, New York. Numerous elements of the RSoXS station were designed for optimal performance for measurements on soft matter systems, where it is of critical importance to minimize beam damage and maximize collection efficiency of polarized x-rays. These elements include a novel optical design, sample manipulator and sample environments, as well as detector setups. Finally, we will report the performance of the measurement station, including energy resolution, higher harmonic content and suppression methods, the extent and mitigation of the carbon absorption dip on optics, and the range of polarizations available from the elliptically polarized undulator source., (© 2021 IOP Publishing Ltd.)