Multi-trench-based technique to improve amorphous SiGe thin-film solar cell performance
In order to improve the electrical performance of the conventional amorphous SiGe thin-film solar cells, a new multi-trench technique has been proposed. In this method, the multi-trench is created in the intrinsic SiGe layer and filled with p-type doped Si. The p-type trenches in the intrinsic SiGe layer improve the electrical performance of the proposed design. Electrical characteristics of the proposed structure are analyzed and optimized by 2-D numerical modeling and compared with conventional amorphous SiGe thin-film solar cell characteristics. The extracted results show that the multi-trench-based technique has excellent effect on the fill factor and efficiency of the device.
Equivalent circuit modeling of SiGe/Si solar cell including interfacial defect effects
In this paper the numerical investigation of the Sil-xGex/Si heterostructure solar cell is proposed. The proposed investigation is based on the study of the immunity of the Sil-xGex/Si heterostructure against the defects degradation effect at nanoscale level (thin films). The numerical analysis takes into consideration the impact of the interface defects on the solar cell behavior. In addition, a new equivalent electrical circuit of the solar cell before and after the setting up of defect degradation effects is developed in this study. The developed equivalent circuit can be implemented into solar cell simulator like: SPICE and PCID, in order to study the impact of the interface defects on the photovoltaic systems. The proposed investigation is intended to be an aid to solar cell designers.
L-band 3D imaging of an Alpine Glacier: Results from the AlpTomoSAR campaign
In this paper we present results from the tomographic analysis of L-Band SAR data acquired in February/March 2014 over the Mittelbergferner glacier, Austrian Alps, during the ESA campaign AlpTomoSAR. The campaign includes coincident in-situ measurements of snow and ice properties, as well as high-frequency Ground Penetrating Radar (GPR) data acquired over a total length of 18 km. The analyses of three-dimensional TomoSAR data cubes shows the complexity of the glacier sub-surface scattering. Most areas are characterized by surface scattering in proximity of the Lidar surface, plus a complex pattern of in-depth volumetric scattering beneath. Various subsurface features observed in GPR transects at 600 MHz and 200 MHz clearly showed up in TomoSAR sections as well. In particular: firn bodies, crevasses, and even the bedrock down to 50 m below the ice surface.