La0.7Sr0.3MnO3 suspended microbridges for uncooled bolometers made using reactive ion etching of the silicon substrates

Shuang Liu (1) , Bruno Guillet (1) , Ammar Aryan (1) , Carlo Adamo (2) , Cédric Fur (1) , Jean-Marc Routoure (1) , Franck Lemarié (3) , D.G. Schlom (2, 4) , Laurence Méchin (1)

1 Equipe Electronique - Laboratoire GREYC - UMR6072
2 Department of Materials Science and Engineering, Cornell University, USA
3 CIMAP - UMR 6252 - Centre de recherche sur les Ions, les MAtériaux et la Photonique
4 KIC - Kavli Institute at Cornell for Nanoscale Science

Suspended La0.7Sr0.3MnO3 (LSMO) microbridges were fabricated using standard silicon micromachining techniques. First epitaxial LSMO thin films were deposited on SrTiO3 (STO) buffered Si (001) substrates by molecular-beam epitaxy. A simple two photolithography step process using the reactive ion etching of the silicon substrate to release the suspended microbridges was developed. The electrical resistivity as a function of temperature of 4 lm wide 50-200 lm long and 75 nm thick LSMO/STO fully processed suspended microbridges was very close to the characteristics of the initial LSMO thin films, demonstrating that the fabrication process did not degrade the quality of the LSMO. The thermal conductance of the processed bolometers was very low (of the order of 10 7WK 1) at 300 K. These structures are promising for uncooled bolometer applications and other micro-electromechanical systems based on LSMO or other epitaxial functional oxides.

Mots clés: Epitaxial oxide; Silicon; Micromachining; Bolometers; Manganites; Molecular beam epitaxy

Domaines: Sciences de l'ingénieur [physics]; Micro et nanotechnologies/Microélectronique

Shuang Liu, Bruno Guillet, Ammar Aryan, Carlo Adamo, Cédric Fur, et al.. La0.7Sr0.3MnO3 suspended microbridges for uncooled bolometers made using reactive ion etching of the silicon substrates. MNE2012 (38th International Micro & Nano Engineering Conference), Sep 2012, Toulouse, France. pp.101-104. ⟨hal-00977471⟩