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37th European Photovoltaic Solar Energy Conference and Exhibition; 516-520, This work reviews on our industrial-oriented passivated emitter and rear cell (PERC) baseline process for Czochralski-grown silicon (Cz-Si) wafers at the Fraunhofer ISE PV-TEC pilot-line. We perform several front side optimizations based on homogeneous emitter doping: finger width reduction of the screen-printed silver fingers, improved silver paste, and implementation of low-temperature thermal oxidation. This yields peak energy conversion efficiencies of 22.1% for boron-doped Cz-Si from LONGi and 22.2% for gallium-doped Cz-Si from Fraunhofer CSP. We show that gallium-doped Cz-Si wafers offer an industrially feasible option to further improve PERC-type but also other solar cell concepts on p-type Cz-Si. We also demonstrate the possibility to omit regeneration procedures that are needed to suppress the boron-oxygen-related light-induced degradation effects as known for conventional borondoped Cz-Si.

36th European Photovoltaic Solar Energy Conference and Exhibition; 345-351, In the PV industry, there is still a sustained cost pressure in the entire production chain of PV modules. Incidentally, the demand for ever higher efficiencies is another challenge to the material quality in substrate production on the one hand and cell technology on the other hand. For the production of monocrystalline silicon ingots by the Cz process, this means the demand for an extremely productive technology of crystal pulling systems as well as for cost-saving processes. Based on these considerations, a mobile recharge system was developed that allows for the multipulling technique that is the sequential pulling of several crystals from a single crucible. This mobile feeding system offers the unique possibility to serve several Cz-pullers time delayed, which means less investment. In addition, an active crystal cooling device has been developed, which can be retrofitted and allows a significant increase in the pull speed. The combination of active crystal cooling with multipulling enables a strong reduction in production costs of silicon crystals. Another way to reduce costs is to use larger melt weights (primary loadings) to minimize unproductive crystal growing process times (neck, shoulder, cone phase). When increasing the primary loadings, however, the process stability must be taken into account. This raises the question to what extent large melt volumes with the resulting turbulent convection phenomena can be controlled without the use of magnetic fields to dampen the convection phenomena.

35th European Photovoltaic Solar Energy Conference and Exhibition; 476-482, The permanent demand for the improvement of solar cell efficiency and reduction of production costs has placed much focus on the multiple Cz-pulling techniques from a single crucible. PVA Crystal Growing Systems GmbH has developed a mobile recharge system for Czochralski pullers, the SiCharger MRS. This system can operate several Cz-pullers with in a consecutive mode and is characterized by low investment costs, reduced silicon consumption and higher output per crucible. This system and its potential were presented in detail at the 33rd EU PVSEC [1]. Another way to save costs due to an increased productivity is a higher pull rate. In order to enable a higher pull speed under stable crystal growth conditions, the hot zone was investigated and optimized by simulating the entire crystal growth arrangement with the commercial program package CGSim [2]. As a result, the pull rate could be increased significantly. In a next approach, an active crystal cooling system was implemented. This cooling device itself consists of a water cooled container, which is placed above the phase boundary of the growing crystal, in order to increase the axial temperature gradient in the growing crystal close to its solidification interface. This system is described in detail in [3]. With this arrangement the heat transport through the crystal is improved so that crystals with 8 inch diameter were grown with a pull rate of 1.8 mm/min resulting in an appreciable saving of process costs.

33rd European Photovoltaic Solar Energy Conference and Exhibition; 495-500, The permanent demand on the improvement of solar cell efficiency and reduction of production costs has placed much focus on the multiple Cz-pulling techniques from a single crucible. PVA Crystal Growing Systems GmbH has developed a mobile recharge system for Czochralski pullers, the SiCharger MRS. This system and its potential was presented in detail at the 33rd EU PVSEC [1]. Another way to save costs while increasing productivity is a higher pull rate. In order to enable a higher pull speed at a stable crystal growth, the hot zone was investigated and optimized. The entire crystal growth arrangement was simulated with the commercial program package CGSim [2]. As a result, the pull rate could be significantly increased resulting in an appreciable saving of energy and process gas. In the next approach, an active crystal cooling system was implemented. This device consists of a water cooled container, which is placed a few centimeters above the phase boundary of the growing crystal, in order to increase the temperature gradient in the growing crystal close to its solidification interface. With this arrangement the heat transport through the crystal is improved. Crystals with 8 inch diameter were grown with a pull rate of 1.7 mm/min.

Contains fulltext : 166652.pdf (Publisher’s version ) (Open Access) Radboud University, 10 februari 2017 Promotor : Hagoort, P. Co-promotor : Willems, R.M. 236 p.

32nd European Photovoltaic Solar Energy Conference and Exhibition; 1064-1068, The permanent demand on the improvement of solar cell efficiency and reduction of production costs has placed much focus on the multiple Cz-crystal pulling technique from one crucible. The use of lower quality silicon as feedstock for monocrystalline material is not an alternative track because it is in contradiction to the quest for high cell efficiencies. PVA Crystal Growing Systems Gmbh has developed a novel mobile recharge system for Czochralski pullers, the SiCharger MRS. This systems is capable of handling silicon feedstock material up to a chip size of 15 mm and was extensively tested under industrial conditions. The assignment for a chip size of 40 mm is currently under series of tests, the results are promising. One MRS-system can serve several pullers, presuming a suitable production organization. Investment cost and thus amortization period are minimized. In this paper the MRS-system is presented in detail as well as its operation during the recharging of the hot crucible. The influence of the different types of feedstock on the recharge process is presented. The segregation effect of impurities on the quality of multiple ingots grown in one crucible is shown.

Contains fulltext : 158955.pdf (Publisher’s version ) (Open Access) The Profile of Music Perception Skills (PROMS) is a recently developed measure of perceptual music skills which has been shown to have promising psychometric properties. In this paper we extend the evaluation of its brief version to three kinds of validity using an individual difference approach. The brief PROMS displays good discriminant validity with working memory, given that it does not correlate with backward digit span (r = .04). Moreover, it shows promising criterion validity (association with musical training (r = .45), musicianship status (r = .48), and self-rated musical talent (r = .51)). Finally, its convergent validity, i.e. relation to an unrelated measure of music perception skills, was assessed by correlating the brief PROMS to harmonic closure judgment accuracy. Two independent samples point to good convergent validity of the brief PROMS (r = .36; r = .40). The same association is still significant in one of the samples when including self-reported music skill in a partial correlation (rpartial = .30; rpartial = .17). Overall, the results show that the brief version of the PROMS displays a very good pattern of construct validity. Especially its tuning subtest stands out as a valuable part for music skill evaluations in Western samples. We conclude by briefly discussing the choice faced by music cognition researchers between different musical aptitude measures of which the brief PROMS is a well evaluated example. 12 p.

Instrumental music and language are both syntactic systems, employing complex, hierarchically-structured sequences built using implicit structural norms. This organization allows listeners to understand the role of individual words or tones in the context of an unfolding sentence or melody. Previous studies suggest that the brain mechanisms of syntactic processing may be partly shared between music and language. However, functional neuroimaging evidence for anatomical overlap of brain activity involved in linguistic and musical syntactic processing has been lacking. In the present study we used functional magnetic resonance imaging (fMRI) in conjunction with an interference paradigm based on sung sentences. We show that the processing demands of musical syntax (harmony) and language syntax interact in Broca’s area in the left inferior frontal gyrus (without leading to music and language main effects). A language main effect in Broca’s area only emerged in the complex music harmony condition, suggesting that (with our stimuli and tasks) a language effect only becomes visible under conditions of increased demands on shared neural resources. In contrast to previous studies, our design allows us to rule out that the observed neural interaction is due to: (1) general attention mechanisms, as a psychoacoustic auditory anomaly behaved unlike the harmonic manipulation, (2) error processing, as the language and the music stimuli contained no structural errors. The current results thus suggest that two different cognitive domains—music and language—might draw on the same high level syntactic integration resources in Broca’s area.

Contains fulltext : 162845.pdf (Publisher’s version ) (Open Access) Developmental dyslexia is often characterized by a dual deficit in both word recognition accuracy and general processing speed. While previous research into dyslexic word recognition may have suffered from speed-accuracy trade-off, the present study employed a novel eye-tracking task that is less prone to such confounds. Participants (10 dyslexics and 12 controls) were asked to look at real word stimuli, and to ignore simultaneously presented non-word stimuli, while their eye-movements were recorded. Improvements in word recognition accuracy over time were modeled in terms of a continuous non-linear function. The words’ rhyme consistency and the non-words’ lexicality (unpronounceable, pronounceable, pseudohomophone) were manipulated within-subjects. Speed-related measures derived from the model fits confirmed generally slower processing in dyslexics, and showed a rhyme consistency effect in both dyslexics and controls. In terms of overall error rate, dyslexics (but not controls) performed less accurately on rhyme-inconsistent words, suggesting a representational deficit for such words in dyslexics. Interestingly, neither group showed a pseudohomophone effect in speed or accuracy, which might call the task-independent pervasiveness of this effect into question. The present results illustrate the importance of distinguishing between speed- versus accuracy-related effects for our understanding of dyslexic word recognition. 16 p.

This paper investigates the dynamics of child-directed speech in longitudinal data from the CHILDES corpus. We quantify the complexity of the speech used by each dialogue participant using simple measures. Our results show that there is a strong correlation in all measures between the complexity of the child’s and the mother’s utterances, indicating that adults adapt their speech at different levels of linguistic processing when interacting with children in dialogue. These correlations remain, albeit weaker, after controling for the effects of the child’s age and for local repetitions in the corpus.