Analysis of the inner collection efficiency in hybrid silicon solar cells

The collection of photogenerated carriers in hybrid silicon solar cells structures were determined by the DICE (dynamic inner collection efficiency) technique. The hybrid solar cells have a microcrystalline <i>n</i>-type emitter and a crystalline <i>p</i>-type base. Cells with amorphous buffers of several thickness and <i>p</i>⁺ back surface field microcrystalline layers were also studied. Spectral response and reflectivity were measured for each sample in order to obtain the internal spectral response or quantum efficiency. These data are the input to DICE analysis, together with the optical parameters of each layer. We observed that the emitter thickness is the most important parameter which defines the solar cell photovoltaic behavior. DICE profiles show that cells with emitter thickness of 80 Å have better collection efficiency than cells with higher thickness values mainly near the surface (until 1 μm below the ITO/microcrystalline interface). The efficacy of the back surface field can be observed with this technique by determining the DICE values near the back metalization and the minority carriers diffusion length can be calculated using the DICE profile in the bulk.The collection of photogenerated carriers in hybrid silicon solar cells structures were determined by the DICE (dynamic inner collection efficiency) technique. The hybrid solar cells have a microcrystalline <i>n</i>-type emitter and a crystalline <i>p</i>-type base. Cells with amorphous buffers of several thickness and <i>p</i>⁺ back surface field microcrystalline layers were also studied. Spectral response and reflectivity were measured for each sample in order to obtain the internal spectral response or quantum efficiency. These data are the input to DICE analysis, together with the optical parameters of each layer. We observed that the emitter thickness is the most important parameter which defines the solar cell photovoltaic behavior. DICE profiles show that cells with emitter thickness of 80 Å have better collection efficiency than cells with higher thickness values mainly near the surface (until 1 μm below the ITO/microcrystalline interface). The efficacy of the back surface field can be observed with this technique by determining the DICE values near the back metalization and the minority carriers diffusion length can be calculated using the DICE profile in the bulk.The collection of photogenerated carriers in hybrid silicon solar cells structures were determined by the DICE (dynamic inner collection efficiency) technique. The hybrid solar cells have a microcrystalline <i>n</i>-type emitter and a crystalline <i>p</i>-type base. Cells with amorphous buffers of several thickness and <i>p</i>⁺ back surface field microcrystalline layers were also studied. Spectral response and reflectivity were measured for each sample in order to obtain the internal spectral response or quantum efficiency. These data are the input to DICE analysis, together with the optical parameters of each layer. We observed that the emitter thickness is the most important parameter which defines the solar cell photovoltaic behavior. DICE profiles show that cells with emitter thickness of 80 Å have better collection efficiency than cells with higher thickness values mainly near the surface (until 1 μm below the ITO/microcrystalline interface). The efficacy of the back surface field can be observed with this technique by determining the DICE values near the back metalization and the minority carriers diffusion length can be calculated using the DICE profile in the bulk.