2026-04-14T03:09:26Zhttps://recercat.cat/oai/request

oai:recercat.cat:2117/4222882026-02-07T09:50:27Zcom_2072_1033col_2072_452950

Annealed phosphorous-doped amorphous silicon as electron selective contact for crystalline germanium thermophotovoltaic cells Rivera Vila, Gerard Gamel, Mansur Mohammed Ali López Rodríguez, Gema Garin Escriva, Moises Martín García, Isidro Àrees temàtiques de la UPC::Energies::Energia solar fotovoltaica Phosphorous diffusion Crystalline germanium Thermophotovoltaics PECVD Thermophotovoltaic devices based on crystalline germanium (c-Ge) substrates that avoid the epitaxial growth of III-V compounds are a promising solution for reducing technological costs of such technology. Heterojunction based on n-type silicon layers deposited by PECVD on c-Ge are good candidates. However, deposited layers with an efficient electron extraction have proven to be difficult given the instability of c-Ge interface that leads to significant amount of recombination. Herein, we present a novel strategy consisting of a high-temperature anneal of a phosphorus-rich amorphous silicon layer deposited by PECVD. The annealing improves the conductivity and passivation of the structure by inducing a diffusion process of not only phosphorus but also silicon, as demonstrated by ToF-SIMS. We optimize the thermal process for high conductivity and surface passivation. The morphological changes are observed using Raman spectroscopy and X-Ray Diffraction, indicating a partial recrystallization of the amorphous silicon layer and confirming the formation of a SiGe alloy at the surface. Finally, the optimized structure is implemented in a device and tested under 1-sun illumination, yielding an efficiency of 4.53% and validating the feasibility of the approach. Postprint (author's final draft) 2025 Conference lecture Restricted access - publisher's policy