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Purpose To develop an infrastructure for structured and automated collection of interoperable radiation therapy (RT) data into a national clinical quality registry. Materials and methods The present study was initiated in 2012 with the participation of seven of the 15 hospital departments delivering RT in Sweden. A national RT nomenclature and a database for structured unified storage of RT data at each site (Medical Information Quality Archive, MIQA) have been developed. Aggregated data from the MIQA databases are sent to a national RT registry located on the same IT platform (INCA) as the national clinical cancer registries. Results The suggested naming convention has to date been integrated into the clinical workflow at 12 of 15 sites, and MIQA is installed at six of these. Involvement of the remaining 3/15 RT departments is ongoing, and they are expected to be part of the infrastructure by 2016. RT data collection from ARIA®, Mosaiq®, Eclipse™, and Oncentra® is supported. Manual curation of RT-structure information is needed for approximately 10% of target volumes, but rarely for normal tissue structures, demonstrating a good compliance to the RT nomenclature. Aggregated dose/volume descriptors are calculated based on the information in MIQA and sent to INCA using a dedicated service (MIQA2INCA). Correct linkage of data for each patient to the clinical cancer registries on the INCA platform is assured by the unique Swedish personal identity number. Conclusions An infrastructure for structured and automated prospective collection of syntactically interoperable RT data into a national clinical quality registry for RT data is under implementation. Future developments include adapting MIQA to other treatment modalities (e.g. proton therapy and brachytherapy) and finding strategies to harmonize structure delineations. How the RT registry should comply with domain-specific ontologies such as the Radiation Oncology Ontology (ROO) is under discussion.

In this work a novel type of substrate for thin film silicon solar cells is studied. The substrate has the advantage of being physically flat to allow the growth of cells with excellent material quality while being optically rough for enhanced light trapping that leads to high short circuit current density. The substrate is made of rough zinc oxide (ZnO) which is grown on a flat silver reflector. The ZnO is then covered with amorphous silicon and the stack is polished to expose the tips of the pyramidal ZnO surface. The ZnO embedded in the amorphous matrix provides the desirable scattering of light while the surface onto which the cell is deposited is flat and allows for the growth of good quality material. We present results of ~4 µm thick microcrystalline silicon solar cells prepared on such substrates with high open circuit voltages of 520 mV. We also demonstrate a large relative efficiency gain of 10 compared to a state of the art cell which is grown directly on an optimized textured substrate. © 2012 Elsevier B.V. All rights reserved.

High reflectivity is essential when a metal is used as back contact and reflector in thin film silicon solar cells. We show that thermal annealing at 150 °C improves the reflectivity of silver films deposited by sputtering at room temperature on nanotextured substrates. The annealing provokes two interlinked effects: rearrangement of the silver layer with a modification of its morphology and an increase of up to 42 in the grain size of the polycrystalline film for the preferential orientation as measured by X ray diffraction. The main consequence of these two mechanisms is a large increase in the reflectivity of silver when measured in air. This reflectivity increase is also noticeable in devices: amorphous silicon thin film solar cells grown on annealed silver films yield higher internal and external quantum efficiencies compared to cells grown on as deposited silver. The morphology modification smoothes down the substrate which is revealed by a clear increase of the open circuit voltage and fill factor of the cells grown on top. An amorphous silicon cell with a 200 nm nominally thick i layer fabricated on a flexible plastic substrate yielded an initial efficiency close to 10 with 15.9 mA/cm 2 of short circuit current using highly reflective annealed textured silver. We also propose for industrial purpose the sputtering of thin silver layer (120 nm) under moderate substrate temperature (~150 °C) to increase the layer reflectivity which avoids lengthening of the back reflector fabrication. © 2011 Elsevier B.V. All rights reserved.