abstract
A major challenge for integration of functional oxides, such as ferroelectrics, into microelectronics and flexible electronics is the reduction of their processing temperature, which needs to be lower than the degradation temperature of silicon and flexible plastic substrates. Aiming that, attention has been given to low-temperature processing of oxide films by chemical solution deposition (CSD). In the field of ferroelectrics, potassium sodium niobate ((K1-xNax)NbO3, KNN) has aroused a special interest due to its eco-friendliness, despite the high crystallization temperature. In this work, polycrystalline KNN thin films have been fabricated for the first time at a temperature as low as 400 degrees C using a modified CSD process, the Seeded Photosensitive Precursor Method (SPPM). Despite this low processing temperature, monophasic and stoichiometric films with appreciable values of remnant polarization, P-r similar to 10.8 mu C/cm(2), and hysteretic piezoresponse are obtained. These results open a window to the direct integration of KNN films into the high-performance electronic devices.
keywords
PHOTOCHEMICAL ACTIVATION; ELECTRICAL-PROPERTIES; CRYSTALLIZATION; PRECURSOR; GROWTH; OXIDES
subject category
Materials Science
authors
Pinho, R; Bretos, I; Jimenez, R; Calzada, ML; Hortigüela, MJ; Otero-Irurueta, G; Ivanov, M; Tkach, A; Costa, ME; Vilarinho, PM
our authors
Maria Elisabete Jorge Vieira Costa
Collaborator
Maxim Ivanov
Junior Researcher
Oleksandr Tkach
Assistant Researcher
Paula Maria Lousada Silveirinha Vilarinho
Vice Director
Rui Manuel de Oliveira Pinho
PhD StudentProjects
CICECO - Aveiro Institute of Materials (UIDB/50011/2020)
CICECO - Aveiro Institute of Materials (UIDP/50011/2020)
Associated Laboratory CICECO-Aveiro Institute of Materials (LA/P/0006/2020)
Collaboratory for Emerging Technologies, CoLab (EMERGING TECHNOLOGIES)
acknowledgements
This work was developed within the scope of the project CICECO- Aveiro Institute of Materials, UIDB/50011/2020, UIDP/50011/2020 & LA/P/0006/2020, financed by national funds through the FCT/MCTES (PIDDAC). Rui Pinho acknowledges FCT for financial support, under the scholarship SFRH/BD/12069/2016; and thanks to JECS Trust for travel grant (Contract#2018195). Inigo Bretos, Ricardo Jimenez and M. Lourdes Calzada acknowledge the support of the Spanish Project PID2019-104732RB-I00 funded by MCIN/AEI/10.13039/501100011033. Alexander Tkach acknowledges FLEXIDEVICE project PTDC/CTMCTM/29671/2017 and individual FCT grant 2021.02284. CEECIND. The authors acknowledge Fatima Zorro and Paulo Ferreira, from the International Iberian Nanotechnology Laboratory - INL, for the STEM characterization.