Influence of a gold seed in transparent V<sub>2</sub>O<sub>x</sub>/Ag/V<sub>2</sub>O<sub>x</sub> selective contacts for dopant-free silicon solar cells

Dielectric/metal/dielectric structures based on vanadium pentoxide with a thin silver interlayer have been optimized to replace traditional transparent electrodes. As would be expected, there is a trade-off in the metal thickness to achieve simultaneously high transparency and low sheet resistance....

Full description

Bibliographic Details
Authors: Nguyen, Hieu Trung, Ros Costals, Eloi, Tom, Thomas, Bertomeu i Balagueró, Joan, Asensi López, José Miguel, Andreu i Batallé, Jordi, Martin Garcia, Isidro, Ortega Villasclaras, Pablo Rafael, Garin Escriva, Moises, Puigdollers i González, Joaquim, Voz Sánchez, Cristóbal, Alcubilla González, Ramón
Format: article
Status:Versión aceptada para publicación
Publication Date:2018
Country:España
Institution:Universidad de Barcelona
Repository:Dipòsit Digital de la UB
OAI Identifier:oai:diposit.ub.edu:2445/127122
Online Access:https://hdl.handle.net/2445/127122
Access Level:Open access
Keyword:Cèl·lules solars
Cèl·lules fotovoltaiques
Silici
Conductivitat elèctrica
Solar cells
Photovoltaic cells
Silicon
Electric conductivity
Description
Summary:Dielectric/metal/dielectric structures based on vanadium pentoxide with a thin silver interlayer have been optimized to replace traditional transparent electrodes. As would be expected, there is a trade-off in the metal thickness to achieve simultaneously high transparency and low sheet resistance. It has been demonstrated that an ultrathin gold seed prevents the tendency of silver to form clusters. This wetting effect reduces the metal thickness needed to form a continuous film, which leads to a higher averaged transmittance and very low sheet resistance. On the other hand, vanadium pentoxide on silicon forms a high quality hole-selective contact. Thus, these structures can be used as an all-in-one transparent electrode and selective contact for a new kind of heterojunction solar cells. This concept has been proved in a 13.3% efficient solar cell fabricated on n-type silicon wafers. Besides dopant-free, the complete fabrication route did not require any sputtered transparent electrode.