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For transfer path analysis (TPA) methods, the description of the source is essential. The possibilities of source characterization are as different as the TPA methods. For the classical methods, the source is considered in the installed state with feedback from the receiver structure, while for component-based TPA the source is described without feedback from the coupled structure. In addition to TPA, source characterization is also used in the product development process for evaluation or comparisons. Also in these cases, the source must be characterized without feedback from the test structure, which can generally be realized by measuring free velocities or blocked forces. Because of the need of external load to reach the components operating point, force measurements are often used. However, the realization of a reactionless test setup for the measurement of forces poses some challenges. The paper presents a setup that can be used to perform a direct force measurement at a point in six degrees of freedom. The necessary boundary conditions to approximate the idealized blocked force assumption are discussed, the calculation of the blocked force in six degrees of freedom is presented, the structural dynamic response at a reference point is calculated and compared with operational measurements.

Pronunciation in second language learning is sometimes challenging, especially the vowels. Vowels such as [i] and [a] are found both in Hausa and Yorùbá but [i:] and [a:] are peculiar to Hausa alone. While Hausa has short and long vowels, Yorùbá has only oral and nasal vowels in their vowel inventories. Such phonemic differences constitute learning challenges, especially for the Yorùbá native speakers. This is a cross-sectional study design using mixed methods to examines the production of high front vowels: [i], and [i:], as well as low: [a], and [a:] Hausa vowels by the Yorùbá speakers to identify which group perform better between group 1 (Yorùbá native speakers who learned Hausa in the secondary school before going to the college of education), and group 2 (Yorùbá native speakers who learned Hausa informally before going to the college of education). The study also seeks to find out vowel substitutions that occur in the pronunciation tasks using 80 participants from 18 years old and above from the College of Education system in Nigeria who were selected based on purposive sampling. The findings were discussed in line with Flege & Bohn’s (2020) ‘Revised Speech Learning Model’. 8 stimuli were audio-recorded, transcribed, and rated by two independent raters, in addition to participant observation techniques adapted. The results of the Mann-Whitney test revealed that group 2 performed better than group 1. The study discovered also that the short [a] in the first and second syllables had the highest frequency of substitution compared to [i], [i:] and [a:] vowels. Such problems have pedagogical implications for learning Hausa as a second language.

The mid short vowels: /e/ and /o/ are among the vowels shared between Hausa and Yorùbá but differ in Hausa mid-high long, front and back vowels: /e:/ and /o:/. The phonemic differences in the two languages have caused learning difficulties among the Yorùbá native speakers to achieve their second language learning desire and competence. Yorùbá-Hausa learners mispronounce certain disyllabic Hausa words due to the substitution of vowels in the first and second syllables. Thus, both lexical and grammatical meanings of the Hausa words are affected. This study examined the production of the 12 Hausa vowels by level 1 and level 3 students who were learning Hausa as a second language to determine if there was a significant difference in how level 1 and level 3 students pronounced the short and long mid-high, front and back Hausa vowels. 88 Yorùbá native speakers were recruited using purposive sampling. Twenty-four different wordlists extracted from Bargery's (1934) Hausa-English dictionary and prepared in carrier phrases were audio-recorded. It was a mixed-method, and the results were discussed within the theoretical framework of Flege and Bohn's (2020) Revised Speech Learning Model and Corder's (1967) 'Error Analysis Model'. The results of the Mann-Whitney U test revealed that participants in level 1 generally performed lower than level 3 participants in the pronunciation of mid-Hausa vowels due to substitutions. Such errors have pedagogical implication in learning Hausa as a second language, and if not addressed accordingly, the standard of Hausa will continue to fall at an undesirable and alarming rate.

Proteins Pfs230 and Pfs48/45 are Plasmodium falciparum transmission-blocking (TB) vaccine candidates that form a membrane-bound protein complex on gametes. The biological role of Pfs230 or the Pfs230-Pfs48/45 complex remains poorly understood. Here, we present the crystal structure of recombinant Pfs230 domain 1 (Pfs230D1M), a 6-cysteine domain, in complex with the Fab fragment of a TB monoclonal antibody (mAb) 4F12. We observed the arrangement of Pfs230 on the surface of macrogametes differed from that on microgametes, and that Pfs230, with no known membrane anchor, may exist on the membrane surface in the absence of Pfs48/45. 4F12 appears to sterically interfere with Pfs230 function. Combining mAbs against different epitopes of Pfs230D1 or of Pfs230D1 and Pfs48/45, significantly increased TB activity. These studies elucidate a mechanism of action of the Pfs230D1 vaccine, model the functional activity induced by a polyclonal antibody response and support the development of TB vaccines targeting Pfs230D1 and Pfs230D1-Pfs48/45., With the aim to advance the development of a P. falciparum transmission blocking vaccine, Singh et al. determine the crystal structure of Pfs230D1 in complex with the Fab fragment of TB mAb 4F12. They further study the cellular localization of Pfs230 on the surface of sexual stages of parasites and the effect of combining TB mAbs against Pfs230 and Pfs48/45.

Berawan is a small ethnic community, numbering fewer than 4,000 members, in the Malaysian state of Sarawak on Borneo Island. There are four language varieties; namely, Long Jegan (LJG), Batu Belah (BB), Long Teru (LTU) and Long Terawan (LTN). This paper describes the development of the preliminary unified Berawan orthography by the authors, in collaboration with representatives from three Berawan communities (BB, LTU and LJG). Smalley’s (1959, 1965) criteria for orthography development are discussed in relation to the authors’ stage framework for orthographic development, which has been adapted from Rempel (1995) within the context of developing the Berawan orthography and the orthographic decisions made by the Berawan. Two additional factors for orthography implementation are proposed. The first stresses the importance of adequate testing, which is essential for both obtaining objective measurements to inform decision making and establishing a well-designed and effective orthography. The second new factor emphasizes the importance of having sufficient time available to learn the developed orthography.

Optical surfaces are achieving increasingly complex shapes which brings out challenges to functionalize them conformally for improved performance. Besides, plastic optics pose a great challenge on coating technologies due to their large coefficient of thermal expansion and poor adhesion of functional coatings. Here, the potential of plasma enhanced atomic layer deposition (PEALD) technique to develop uniform and 3D-conformal films on polycarbonate (PC) (Makrolon) planar and dome substrates has been explored. It enables to grow conformal Al2O3, TiO2 and SiO2 films on steeply curved PC substrates. Moreover, we demonstrate an 11-layer antireflection (AR) coating reaching about 0.2% reflection at 905 nm wavelength on the entire outer surface of several PC domes along with a consistent optical performance on the inner surface. The adhesion and environmental stability tests according to ISO-9211-04 resulted in promising adhesive and environmentally durable films on PC dome optics. These results suggest a possible way to grow uniform, dense, conformal, and stable optical coatings on sensitive polymer PC substrates for desired optical applications.

Guest Editors Martin Burkhardt and Vicky Philipsen summarize the papers of the Special Series on EUV Masks.

Jutta Krimm-Beumann (Bearb.): Die Bestände des Generallandesarchivs Karlsruhe. Teil 5: Nichtstaatliches Archivgut (69–70). Stuttgart: Kohlhammer 2011. 389 S. ISBN 978-3-17-021761-4. Geb. € 40,–

Gert Kollmer-von Oheimb-Loup / Sibylle Lehmann-Hasemeyer / Stefanie van de Kerkhof (Hg.), Ökonomie und Ethik, Beiträge aus Wirtschaft und Geschichte (Stuttgarter historische Studien zur Landes- und Wirtschaftsgeschichte, Bd. 28), Stuttgart: Jan Thorbecke Verlag 2017. 299 S. ISBN 978-3-7995-5579-1. € 45,–

Thomas Schuetz, Die Leinenwarenherstellung im Königreich Württemberg. Technologietransfer und technisches Expertenwissen im 19. Jahrhundert (Beiträge zur Kulturwissenschaft, Bd. 40), Oberhausen: Athena-Verlag 2018. 279 S. ISBN 978-389896-685-6. € 38,–

Efforts to develop a vaccine for the elimination of malaria include the use of carrier proteins to assemble monomeric antigens into nanoparticles to maximize immunogenicity. Recombinant ExoProtein A (EPA) is a detoxified form of Pseudomonas aeruginosa Exotoxin A which has been used as a carrier in the conjugate vaccine field. A pilot-scale process developed for purification of EPA yielded product that consistently approached a preset upper limit for host cell protein (HCP) content per human dose. To minimize the risk of bulk material exceeding the specification, the purification process was redeveloped using mixed-mode chromatography resins. Purified EPA derived from the primary and redeveloped processes were comparable following full biochemical and biophysical characterization. However, using a process specific immunoassay, the HCP content was shown to decrease from a range of 0.14–0.24% w/w of total protein to below the level of detection with the revised process. The improved process reproducibly yields EPA with highly similar quality characteristics as the original process but with an improved profile for the HCP content.

High NA EUV lithography will offer single exposure patterning for pitches below 28nm, simplifying process flows. However, overlay error complexity will increase. Specifically, a semiconductor build will require use of both high NA EUV tools that can only expose half the field size of low NA EUV and optical tools. This means that to achieve full productivity on the low NA EUV and optical tools used, a semiconductor build using these tools will need to minimize overlay error back to a scanner map exposed with the high NA EUV tool that has twice the number of exposures. Overlay error minimization on full field tools takes advantage of keeping exposure maps constant between different layers so that scan direction and step direction are maintained. This is not possible when using a high NA EUV tool in a semiconductor build unless the number of scans on the low NA and optical tools are doubled, thus decreasing the productivity on those tools. Having a full field minimize overlay error back to two half fields results in new required overlay controls between the two half fields to achieve low overlay error. In particular, stitch overlay control for the half field exposures can be very helpful to achieving good overlay error between a layer exposed with full field exposure map and a layer exposed with a half field exposure map. To get early learning on these effects, we designed a test reticle with a unique “figure 8” black border that allows step plans to be exposed with either half or full field exposures. To get rapid learning the reticle is designed to take advantage of resist-to-resist overlay targets that engage with each other when there is a programed 180 um step delta between the two exposures. The effects of order of exposures as well as scan and step direction differences between the half field and full field step plans are investigated.

As the semiconductor industry continues pushing Moore’s law to the next node, interconnect structures scaling will be a key element to performance improvement of functional devices. However, the requirements for low LCDU and defectivity of these interconnect structures have become more stringent with continuous scaling. In this paper, a fundamental study is conducted to understand the impact of various factors on the patterning of EUV single exposure vias, and to find effective strategies to shrink CD while improving LCDU and defectivity. The work is based on a 40 nm pitch orthogonal via array baseline, and probes different patterning factors including illumination, resist materials, stack, scanner, and develop methods for LCDU improvement and defectivity reduction. The patterns are transferred to bottom dielectrics to study the evolution of LCDU and defectivity during etching.

In 2015 IBM announced the first 7 nm test chip patterned with Extreme Ultraviolet Lithography (EUV) technology, enabling 36nm back end of the line (BEOL) metal pitch and self-aligned contact. Five years later, EUV has become the mainstream enabler for 7 nm node manufacturing, including the recent announcement of IBM Power10 high-performance chip. The high-performance definition of this technology, essential to IBMs server chips, has unique requirements that push the process complexity even further. In this paper, we will review some of the challenges and patterning solutions that will allow successful implementation of high-performance design definitions. We will also discuss our current efforts to extend the use of single expose EUV in the printing of interconnects to a second node, over a multi-patterning scheme, by replicating our strategy of co-optimization across all contributors to patterning success. We will review a few examples of this approach, including resolution improvements of our latest NXE3400 EUV system, all of which have allowed us to realize significant yields for our transistor interconnects at 28nm pitch. The entitlement of each process and material will be gauged through a robust characterization methodology that includes an understanding of the defect mode modulated, as well its ultimate correlation to electrical yield.

Martin Burkhardt, Archive der Freiherren von Degenfeld-Neuhaus und Gemmingen- Hornberg-Babstadt, Urkundenregesten 1439 bis 1902 (Inventare der nichtstaatlichen Archive in Baden-Württemberg, Bd. 39), Stuttgart: Kohlhammer 2013. 242 S. ISBN 978-3-17-023346-1. Geb. € 24,–

Malaria elimination requires tools that interrupt parasite transmission. Here, we characterized B cell receptor responses among Malian adults vaccinated against the first domain of the cysteine-rich 230kDa gamete surface protein Pfs2301–3 to neutralize sexual stage P. falciparum parasites and halt their further spread. We generated nine Pfs230 human monoclonal antibodies (mAbs). One mAb potently blocked transmission to mosquitoes in a complement-dependent manner and reacted strongly to gamete surface while eight mAbs showed only low or no blocking activity. This study provides a rational basis to improve malaria vaccines and develop therapeutic antibodies for malaria elimination.

Berawan is an endangered Austronesian language family consisting of four lects, which are Batu Belah, Long Teru, Long Jegan, and Long Terawan. Their settlements are located in the Malaysian state of Sarawak. The impetus for a unified orthography came from the Berawan community, who desire to write their lects consistently and reflecting the way they speak. The unified orthography was developed starting with a phonological analysis of the Berawan lects. This was followed by several orthography workshops and discussions with individual Berawan communities, culminating in a combined orthography workshop in which a unified orthography was agreed upon. The aim of the paper is to provide the groundwork for establishing the unifed orthography of the Berawan language family. A phonological comparison of the four Berawan varieties is included for this purpose. The phonological descriptions are taken from Burkhardt (2014). Smalley’s (1959, 1965) maxim of ‘maximal representation of speech’ and Rogers’s (2005) ‘shallow orthography’ approach are employed. On this basis, issues that arise for graphemic representation of Berawan phonemes are then discussed and the decisions made by the participants of the combined workshops are described. The paper also touches on issues encountered throughout the discussion. The issues that arose are primarily related to the differences in orthographic systems between the Berawan lects and the Malay language. The paper ends with a proposed unified Berawan orthography

With aggressive scaling of single-expose EUV lithography to the sub-7 nm node, stochastic variations play a prominent role in defining the lithographic process window. Fluctuations in photon shot noise, absorption and subsequent chemical reactions can lead to stochastic failure, directly impacting electrical yield. Fundamental characterization of the mode and magnitude of these variations is required to define the threshold for failure. In this work, a complementary series of techniques is enlisted to probe the nature and modulation of stochastic variation in single exposure EUV patterning. Unbiased line edge roughness (LER), local critical dimension uniformity (LCDU) and defect inspection techniques are employed to monitor the frequency of stochastic variations leading to failures in line/space and via patterning. Using this methodology, we explore the modulation of stochastic variations by different photoresists and illuminations, with emphasis on material and process down-selection for improved yield at the sub-7 nm node.

Transmission-blocking vaccines are based on eliciting antibody responses in the vertebrate host that disrupt parasite development in the mosquito vector and prevent malaria transmission. The surface protein Pfs47 is present in Plasmodium falciparum gametocytes and female gametes. The potential of Pfs47 as a vaccine target was evaluated. Soluble full-length recombinant protein, consisting of three domains, was expressed in E. coli as a thioredoxin fusion (T-Pfs47). The protein was immunogenic, and polyclonal and monoclonal antibodies (mAb) were obtained, but they did not confer transmission blocking activity (TBA). All fourteen mAb targeted either domains 1 or 3, but not domain 2 (D2), and immune reactivity to D2 was also very low in polyclonal mouse IgG after T-Pfs47 immunization. Disruption of the predicted disulfide bond in D2, by replacing cysteines for alanines (C230A and C260A), allowed expression of recombinant D2 protein in E. coli. A combination of mAbs targeting D2, and deletion proteins from this domain, allowed us to map a central 52 amino acid (aa) region where antibody binding confers strong TBA (78-99%). This 52 aa antigen is immunogenic and well conserved, with only seven haplotypes world-wide that share 96–98% identity. Neither human complement nor the mosquito complement-like system are required for the observed TBA. A dramatic reduction in ookinete numbers and ookinete-specific transcripts was observed, suggesting that the antibodies are interacting with female gametocytes and preventing fertilization.

Stochastic effects are a major concern for yield enablement as we look towards extending the use of single-expose EUV lithography in both trench and via levels. For example, in trench levels stochastic effects lead to two competing defect modes: line breaks and microbridges, both of which are highly CD-dependent and lead to patterning cliffs that narrow the process window as the pitch decreases. In order to push the limits of effective pitch resolution, a fundamental understanding of the patterning process space is required, including imaging and mask contributions, material contributions, as well as develop, and etch contributions. In this paper we will discuss several strategies to modulate and gain fundamental understanding of stochastic effects. In term of the illumination contribution, recently Burkhardt et al. investigated phase effect in EUV through simulation, demonstrating that the images shift caused by a focus shift in monopole illumination can be used to make split images overlap, thus enhancing the contrast in a dipole. We will show that this approach can be used to modulate stochastic effects, specifically defectivity and line edge roughness, and directly correlate these modulations to electrical yield detractors. We will also discuss alternate approaches to understand interfacial effects between the resist and underlying substrate that can impact stochastic defectivity.

With the introduction of EUV lithography into early manufacturing, the lithography community still struggles with some imaging issues, like the magnitude of usable depth of focus, and reduced contrast which can impact stochastic effects such as defectivity and line edge roughness. In recent years EMF mask effects and their impact on best focus shift in EUV lithography were investigated, and alternative absorber stacks were proposed in order to improve control of focus and contrast. Recently, interest in phase shifting masks has resurfaced, and there are proposals for alternative absorber stacks that depend on feature type to be patterned. In this paper, we investigate the phenomenon that for a dipole the separate images of the two monopoles do not overlap with each other. This means that the contrast for the dipole is measurably lower than that of the individual monopoles. We discuss the impact of this effect on contrast and usable depth of focus, propose a method to measure this image split effect, and investigate which absorber materials can reduce it. One approach to suppressing the image split has been the choice of a material that is index matched to vacuum, which therefore shows a negligible image split behavior. While this image split is indeed largely suppressed for absorbers with n ≈ 1, those materials have markedly low intrinsic image contrast, making them unsuitable as absorbers. Instead, we have converged on absorbers that create either a significant phase shift or feature very strong absorption, with recent proposals coming close to a π phase shift for attPSM. We hypothesize that the close index match to vacuum is detrimental to imaging because a larger part of the light is absorbed which would otherwise have contributed to imaging.

Development of a Plasmodium falciparum (Pf) transmission blocking vaccine (TBV) has the potential to significantly impact malaria control. Antibodies elicited against sexual stage proteins in the human bloodstream are taken up with the blood meal of the mosquitoes and inactivate parasite development in the mosquito. In a phase 1 trial, a leading TBV identified as Pfs25-EPA/Alhydrogel® appeared safe and immunogenic, however, the level of Pfs25-specific antibodies were likely too low for an effective vaccine. Pfs230, a 230-kDa sexual stage protein expressed in gametocytes is an alternative vaccine candidate. A unique 6-cysteine-rich domain structure within Pfs230 have thwarted its recombinant expression and characterization for clinical evaluation for nearly a quarter of a century. Here, we report on the identification, biochemical, biophysical, and immunological characterization of recombinant Pfs230 domains. Rabbit antibodies generated against recombinant Pfs230 domains blocked mosquito transmission of a laboratory strain and two field isolates using an ex vivo assay. A planned clinical trial of the Pfs230 vaccine is a significant step toward the potential development of a transmission blocking vaccine to eliminate malaria.

The Long Terawan Berawan system of vowel phonemes consists of one monophthong in the antepenult, schwa, and four monophthongs in the penult, i, ə, a , and u . However, the final syllable exhibits ten monophthongs ( i, ĭ, e, ĕ, a, a, u, ŭ, o, ŏ) and six diphthongs ( əi, ǝu, ai, ai, au, au ). The paper describes how the Long Terawan vowel phoneme system emerged from a Proto-Western Malayo-Polynesian system of four monophthongs (*i, *ə, *a, *u).

Background: With aggressive scaling of single-expose (SE) extreme ultraviolet (EUV) lithography to the sub-7-nm node, stochastic variations play a prominent role in defining the lithographic process window (PW). Fluctuations in photon shot noise, absorption, and subsequent chemical reactions can lead to stochastic failure, directly impacting electrical yield. Aim: Fundamental characterization of the mode and magnitude of these variations is required to define the threshold for failure. Approach: A complementary series of techniques is enlisted to probe the nature and modulation of stochastic variation in SE EUV patterning. Unbiased line edge roughness (LER), local critical dimension uniformity (LCDU), and defect inspection techniques are employed to monitor the frequency of stochastic variations leading to failures in line/space (L/S) and via patterning. Results: When characterizing different resists and illumination conditions, there is no change in unbiased LER or via LCDU with increasing critical dimension (CD). Stochastic defect density is correlated with CD for both L/S and via arrays, and there is a strong correlation with L/S electrical yield data. Conclusions: Traditional 3σ LER and via LCDU measurements are not sensitive enough to define and improve PW. For PW centering and yield improvement, stochastic defect inspection is a necessity.

Transmission-blocking vaccines are based on eliciting antibody responses in the vertebrate host that disrupt parasite development in the mosquito vector and prevent malaria transmission. The surface protein Pfs47 is present in Plasmodium falciparum gametocytes and female gametes. The potential of Pfs47 as a vaccine target was evaluated. Soluble full-length recombinant protein, consisting of three domains, was expressed in E. coli as a thioredoxin fusion (T-Pfs47). The protein was immunogenic, and polyclonal and monoclonal antibodies (mAb) were obtained, but they did not confer transmission blocking activity (TBA). All fourteen mAb targeted either domains 1 or 3, but not domain 2 (D2), and immune reactivity to D2 was also very low in polyclonal mouse IgG after T-Pfs47 immunization. Disruption of the predicted disulfide bond in D2, by replacing cysteines for alanines (C230A and C260A), allowed expression of recombinant D2 protein in E. coli. A combination of mAbs targeting D2, and deletion proteins from this domain, allowed us to map a central 52 amino acid (aa) region where antibody binding confers strong TBA (78-99%). This 52 aa antigen is immunogenic and well conserved, with only seven haplotypes world-wide that share 96–98% identity. Neither human complement nor the mosquito complement-like system are required for the observed TBA. A dramatic reduction in ookinete numbers and ookinete-specific transcripts was observed, suggesting that the antibodies are interacting with female gametocytes and preventing fertilization., Malaria vaccines: Targeting transmission Transmission blocking activity (TBA) of malaria vaccines can potentially target parasite stages either within the human host or the mosquito vector. A team led by Carolina Barillas-Mury at the National Institutes of Health, USA, engineered a vaccine targeting the protein Pfs47 which is present mainly on the surface of Plasmodium falciparum gametocytes. Full-length Pfs47 elicits no TBA; however, an antigen based on a modified version of the central region of Pfs47’s domain 2 generates antibodies with potent TBA in mice. This TBA is independent of human complement or a mosquito complement-like system. Instead, such TBA antibodies likely function by interfering with female gametocytes and preventing fertilization. The Pfs47 region eliciting potent TBA is highly conserved in P. falciparum, suggesting the possibility of a broadly-effective vaccine or synergy with other vaccine target antigens.

The Berawan are a small Orang Ulu people group to which four longhouse communities belong: Long Jegan and Long Teru on the Tinjar River, and Long Terawan and Batu Belah on the Tutoh River. The Tutoh and the Tinjar are tributaries of the Baram river. This paper presents a socio-economic sketch of the Berawan in the early 1960s and contrasts it with the early 21st century situation. A picture is drawn of the social organisation and livelihood of the Berawan community. The following trends are discernible: Longhouse living has become more comfortable but at the same time more cash dependent. The education level of the Berawan has risen significantly while their opportunities to engage in traditional livelihood activities such as rice planting, hunting and fishing are reduced nowadays due to the conversion of vast tracts of lands into palm oil plantations and the silting of the rivers. This has increasingly led the younger generation to migrate out of the village. On the other hand, contrary to popular belief that the tourism industry has a primarily adverse influence on ethnic minority culture, we found that the economic value that tourism offers can promote local culture in encouraging people to remain on their ancestral land.

The gear whine phenomenon in vehicles is a well-known acoustic issue which often needs a development of individual measures. Especially in rear- wheel and four-wheel drive vehicles, the acoustical optimization of the rear axle leads to the major goal conflict: improvement of the vibrational isolation of the rear axle versus excellent driving dynamics of the vehicle. A promising solution for this issue is described in this paper. The key objective is to reduce the noise contributions of the rear axle using an active vibration control system (AVC) based on piezoelectric actuators on the transfer path from the axle into the vehicle. In the first part of the paper, the development process of the AVC system is described. In the second part of the paper, a rear axle test bench is presented which is used to validate the simulation results. A multi component control algorithm has been implemented in order to get an optimum reduction of relevant forces at the mounting points to the vehicle using one or more actuators. In preparation for a series launch of the AVC system, an assembly concept for applying the piezoelectric actuators to the rear sub frame in a series production process is presented.

The extended rod-like Plasmodium falciparum circumsporozoite protein (CSP) is comprised of three primary domains: a charged N terminus that binds heparan sulfate proteoglycans, a central NANP repeat domain, and a C terminus containing a thrombospondin-like type I repeat (TSR) domain. Only the last two domains are incorporated in RTS,S, the leading malaria vaccine in phase 3 trials that, to date, protects about 50% of vaccinated children against clinical disease. A seroepidemiological study indicated that the N-terminal domain might improve the efficacy of a new CSP vaccine. Using a panel of CSP-specific monoclonal antibodies, well-characterized recombinant CSPs, label-free quantitative proteomics, and in vitro inhibition of sporozoite invasion, we show that native CSP is N-terminally processed in the mosquito host and undergoes a reversible conformational change to mask some epitopes in the N- and C-terminal domains until the sporozoite interacts with the liver hepatocyte. Our findings show the importance of understanding processing and the biophysical change in conformation, possibly due to a mechanical or molecular signal, and may aid in the development of a new CSP vaccine.

In order to succeed with such low-k1 lithography at EUV wavelength, we need to be able to print a grating at high contrast similar to ArF immersion tools, where a contrast exceeding 0.95 is achieved routinely. All 2d printing is composed of interference of x and y-directed diffraction orders and high contrast in 2d thus depends on such 1d grating contrast. Any low-k1 imaging will use either dipole or some other sort of extreme off-axis illumination such as cross-quad (cQuad). The two relevant magnitudes for any high contrast are the intrinsic contrast due to a monopole, and the spatial shift of the two images that are generated by the two monopoles making up the dipole exposure. In EUV with current absorbers, high contrast can currently only be achieved using monopole illumination, a technique that does not lend itself to process integration due to removal of wafer side telecentricity and resulting overlay problems at all but preferred pitch. For dipole illumination at low-k1 pitches, we collect only 0th order light and only one 1st diffracted order for each pole. This means that for a dipole at the resolution limit, the final image for horizontal l/s patterns consists of only four incident waves, one TE and one TM wave for each of the poles. In this paper, we screen absorber by n and k values. In the process, we introduce phasor notation in order to gain insight into the behavior of the absorber and try to understand the metrics. We investigate intrinsic contrast and image blur due to monopole image shift.

The feature scaling and patterning control required for the 7nm node has introduced EUV as a candidate lithography technology for enablement. To be established as a front-up lithography solution for those requirements, all the associated aspects with yielding a technology are also in the process of being demonstrated, such as defectivity process window through patterning transfer and electrical yield. This paper will review the current status of those metrics for 7nm at IBM, but also focus on the challenges therein as the industry begins to look beyond 7nm. To address these challenges, some of the fundamental process aspects of holistic EUV patterning are explored and characterized. This includes detailing the contrast entitlement enabled by EUV, and subsequently characterizing state-of-the-art resist printing limits to realize that entitlement. Because of the small features being considered, the limits of film thinness need to be characterized, both for the resist and underlying SiARC or inorganic hardmask, and the subsequent defectivity, both of the native films and after pattern transfer. Also, as we prepare for the next node, multipatterning techniques will be validated in light of the above, in a way that employs the enabling aspects of EUV as well. This will thus demonstrate EUV not just as a technology that can print small features, but one where all aspects of the patterning are understood and enabling of a manufacturing-worthy technology.

As feature sizes become smaller and smaller, the complexity and the cost of using multiple patterning with 193i becomes a significant issue in lithography. Hence, EUV starts to play an important role for 7nm node and beyond. Industry is now investigating solutions on all major EUV components – source, resist mask technology, as well as resolution enhancement techniques (RET), including sub-resolution assist features (SRAFs). Unlike ArF lithography, the non-telecentricity of the EUV optical system coupled with the relatively thick mask stack causes shadowing effects. This asymmetric imaging may in turn have an impact on assist feature placement, requiring different SRAF rules for different directions at the edges and corners. In this work, simulation studies were conducted using Calibre on 20x20 nm contact patterns through pitch to investigate the impact of assist features. Assist features were varied as a function of horizontal / vertical positions independently and the image quality parameters such as depth of focus (DOF), MEEF, best focus (BF) shift and overlapping process window were monitored with and without SRAFs. Both rules-based and model based assist feature placements were implemented for selected patterns. Results indicate that inclusion of assist features for contact arrays improve individual and overlapping process windows with minimal effect on best focus shift. Wafer data collected from these patterns confirmed the improvement in overlapping process window with the inclusion of assist features.

The printing of contact holes using positive tone development typically requires the interference of more than the 0th and 1st diffracted orders. In the 2d case and cQuad illumination in a positive tone process, if (0,0), (±1,0), and (0,±1) are exclusively present, the relevant contrast for imaging can in the best case not rise above 0.33, which is typically insufficient for a good process window. And this maximum value can only be achieved if the (0,0) and (±1,0) orders are matched to give a perfect sine wave of perfect contrast in y while the (0,0) and (0,±1) orders yield perfect contrast in x . In reality, the contrast is quite a bit lower. On the other hand, for negative tone development we are interested in the minima of the intensity–the dark locations in the image–and if we can manage to reduce the intensity in the minima we can achieve a high contrast image. Through a choice of RET and illumination, we manage to achieve a resolution for contact holes in 2d at k 1 values that can otherwise be achieved only for 1d imaging. Earlier work has been done on double exposures that exposed in the same resist a horizontal grating with x-dipoles and subsequently a vertical grating with y dipoles, without intermediate process steps. This yielded a high contrast image in resist at k 1 1 We show that an equivalent result can be achieved in a single exposure with a single mask, at admittedly high dose. We investigate the process parameters and the related mask tolerances, and find a non-intuitive result for the mask pattern that yields an optimized image at given mask specifications. Finally, we investigate the extension of this technique to EUV through simulations and experiments.

Conjugated rod-coil diblock copolymers self-assemble due to a balance of liquid crystalline (rod-rod) and enthalpic (rod-coil) interactions. Previous work has shown that while classical block copolymers self-assemble into a wide variety of nanostructures, when rod-rod interactions dominate self-assembly in rod-coil block copolymers, lamellar structures are preferred. Here, it is demonstrated that other, potentially more useful, nanostructures can be formed when these two interactions are more closely balanced. In particular, hexagonally packed polylactide (PLA) cylinders embedded in a semiconducting poly(3-alkylthiophene) (P3AT) matrix can be formed. This microstructure has been long-sought as it provides an opportunity to incorporate additional functionalities into a majority phase nanostructured conjugated polymer, for example in organic photovoltaic applications. Previous efforts to generate this phase in polythiophene-based block copolymers have failed due to the high driving force for P3AT crystallization. Here, we demonstrate that careful design of the P3AT moiety allows for a balance between crystallization and microphase separation due to chemical dissimilarity between copolymer blocks. In addition to hexagonally packed cylinders, P3AT-PLA block copolymers form nanostructures with long-range order at all block copolymer compositions. Importantly, the conjugated moiety of the P3AT-PLA block copolymers retains the crystalline packing structure and characteristic high time-of-flight charge transport of the homopolymer polythiophene (μ(h) ~10(-4) cm(2) V(-1) s(-1)) in the confined geometry of the block copolymer domains.

Non-volatile memory devices based on the charge transfer complex copper-7,7,8,8 tetracyanochinodimethane were fabricated on ridged and flexible substrates with special emphasis on their general functionality and cross talk behaviour in 4 × 4 passive matrix arrays. Device characteristics have been investigated at elevated temperatures during operation (ranging from room temperature to 120 °C) under ambient conditions without encapsulation. To explore the influence of mechanical stress on device performance, the memory cells on flexible polyethylene terephthalate substrates were bended during operation, up to a convex and concave radius of 4 mm. The detected shift of the switching voltages and the decrease of reliability can be attributed to stress induced cracks in the active layer.