Optical and Electrical Characterizations of Uncooled Bolometers Based on LSMO Thin Films

Abstract

In this paper the optical and electrical characterization of a 75 × 75 µm2 uncooled bolometers based on free-standing La0.7Sr0.3MnO3 /CaTiO3 (LSMO/CTO) thin films fabricated by micromachining of the silicon substrates is presented. R(T) curves have been compared to electro thermal simulations. Its thermal conductance was measured to be 9 × 10−6 W·K−1 around 300 K. The optical characterization was performed by modulating the power of a 635 nm laser diode and was carried out at different bias currents and temperatures. Finally, the frequency dependence of the bolometer presented at different temperatures and at optimal current shows that both sensitive and fast uncooled bolometers can be fabricated using suspended LSMO thin films.

Keywords

• bolometer
• thermal conductance
• frequency response