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State-of-the-art surface passivation results are obtained on undiffused p-type commercial-grade Czochralski Si wafers with effective surface recombination velocity S eff values of ∼8 cm/s and implied open-circuit voltage iV o c values of up to 715 mV with an industrially fired dielectric stack of silicon oxide and silicon nitride (SiO x /SiN x ) deposited in an industrial inline plasma-enhanced chemical vapor deposition reactor.We are able to controllably vary the total positive charge density Q to tal in the stack by more than one order of magnitude (10 11 -10 12 cm −2 ) with no impact on midgap interface state density D it,m idgap (5 × 10 11 eV −1 ·cm −2 ) by altering the deposition temperature of the SiO x layer in the stack. We show experimentally that, for inversion conditions, S eff scales with the inverse square of the charge density 1/Q 2 to tal , which is in good agreement with theory. Based on the measured injection-level-dependent minority carrier lifetimes and the total positive charge densities, it is shown that films with higher positive charge density have higher 1-sun V o c and fill factor (FF) potential. Large-area alloyed aluminum local back surface field solar cells confirmed this by showing higher conversion efficiency by 0.17% absolute due to improved cell V o c and FF of the solar cells featuring a SiO x /SiN x stack with a higher Q to tal .Index Terms-Charge engineering, crystalline silicon, industrial firing, injection-level dependence, interface properties, lowtemperature surface passivation, SiO x /SiN x stacks. search Institute of Singapore, Singapore. His research interests include advanced fabrication and characterization of high-efficiency silicon wafer solar cells.

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The present article considers the (non-)relationship of German educational institutions with the field of community music, a field of work currently without an independent designation in Germany. Beginning with the philosophies of its Musikschulen and Musikhochschulen, the article goes on to describe teaching traditions and funding structures in Germany. Originating from the ideal of superlative artistic performance, the quest for excellence has spawned the so-called ‘Meisterlehre’, that is to say the teaching model in which the tutor as ‘master’ passes on all his knowledge and expertise to his apprentice. For the vast majority of students, a performing career is their defining goal, in spite of the increasing precariousness of the profession. Other forms of artistic communication are often perceived as a failure in this respect, and receive accordingly less recognition. This situation has contributed to the fact that community music in Musikhochschulen has so far garnered little attention. In Germany there are a large number of activities on offer, which come under the heading of community music, and a demand for specifically trained musicians is indeed discernible, but as yet no awareness has evolved of the opportunity that a career in community music represents. Neither the remits of educational establishments nor students’ goals are in line with this, and perspectives often change only when confronted with the harsh reality of the profession. Related fields of work, such as arts education and arts-based social work, may seem to cover the domain; yet community musicians work primarily as performing artists and not as educators – a distinction that is difficult to fathom, given the prevailing artistic attitudes. In order to professionalize community music, a structured form of professional development would seem to be the most appropriate way forward at this point. Questions arising in a professional context could be properly dealt with, and a platform to achieve more recognition for community music as an artistic endeavour could be built. Once an artistic identity is established, the ensuing possibilities for a community musician to take effect in society are manifold.

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