RT Journal Article
T1 Correlated effects of fluorine and hydrogen in fluorinated tin oxide (FTO) transparent electrodes deposited by sputtering at room temperature
A1 Morán Pedroso, María
A1 Gago Fernández, Raúl
A1 Julin, Jaakko
A1 Salas Colera, Eduardo
A1 Jiménez, Ignacio
A1 De Andrés, Alicia
A1 Prieto de Castro, Carlos Andrés
AB The optical and electrical properties of fluorinated tin oxide (FTO) films deposited at room temperature by sputtering have been investigated varying the fluorine content and the hydrogen atmosphere. The complex behavior of the obtained films is disclosed using a wide set of characterization techniques that reveals the combined effects of these two parameters on the generated defects. These defects control the electrical transport (carrier density, mobility and conductivity), the optical properties (band gap and defects-related absorption and photoluminescence) and finally promote the amorphization of the samples. H2 in the sputtering gas does not modify the H content in the films but induces the partial reduction of tin (from Sn4 to Sn2) and the consequent generation of oxygen vacancies with shallow energy levels close to the valence band. A variation of up to four orders of magnitude in electrical conductivity is reported in samples with the appropriate fluorine doping and hydrogen fraction in the sputtering gas, maintaining excellent optical transparency. Optimized room temperature grown electrodes reach sheet resistance ~20 Omega and transparency 90%. This room temperature deposition process enables film preparation on flexible organic substrates, such as polyethylene terephthalate (PET), with identical performance of doubtless interest in flexible and large scale electronics.
PB Elsevier
SN 0169-4332
YR 2021
FD 2021-01-30
LK https://hdl.handle.net/10016/35960
UL https://hdl.handle.net/10016/35960
LA eng
NO We would like to thank IDIVAL for financial support, Projects N°NVAL16/17, INNVAL19/18 and NVAL18/07. CRL thanks the MINECO for the Juan de la Cierva Formación grant (ref. FJCI-2015-25306). This work has been supported by the Spanish MINECO, Instituto de Salud Carlos III, the European Union FEDER funds under Projects ref. PI16/00496 (AES 2016), PI19/00349 and DTS19/00033 (AES 2019). The authors are grateful to Dr F Madrazo and the Laser Microscopy Unit of the IDIVAL Institute for the use of the Confocal Raman Imaging Microscope.
DS e-Archivo
RD 27 jul. 2024