Introduction to Stronium Ruthenate (SrRuO3) Thin Films

SrRuO3 (SRO) is a perovskite-type oxide material that has recently gained attention due to its metallic like conductivity and magnetic properties. These properties make SrRuO3 a useful material for thin film investigations, particularly as a current collector in various electronic and energy storage devices.

Crystal Structure of SrRuO3

SrRuO3 has a perovskite-type crystal structure with a layered cubic arrangement of Sr, Ru, and O ions. The metallic-like conductivity of SrRuO3 arises from the presence of partially filled Ru 4d orbitals, which are highly conductive and provide the material with its unique electrical properties.

Properties of SrRuO3

In addition to its high conductivity, SrRuO3 has several other properties that make it a useful material for thin film investigations. These include its high thermal stability, high magnetic ordering temperature, and strong magnetic coupling between the Ru ions. 

Epitaxial Growth of SrRuO3 Thin Films

SrRuO3 thin films can be grown epitaxially on various substrates, including SrTiO3, LaAlO3, and NdGaO3, which have a good lattice match to SrRuO3. Pulsed Laser Deposition (PLD) is a common method used for the growth of SrRuO3 thin films, and the growth conditions, including oxygen pressure and temperature, can be optimized to achieve the desired properties in the film.

Films Grown Epitaxially on SrRuO3

Typically perovskites can be grown epitaxially on SrRuO3 interlayer, these typically emply an SrTiO3 substrate underneath. Many other materials can also be grown on SrRuO3 as well such as battery cathode materials including spinel and layered materials such as LiMn2O4, high voltage LMNO, LiCoO2, and layered-NMC etc, where the perovskite has a match with their cubic lattices.

Mechanical Stability of SrRuO3 Targets

Unlike many of the other materials we work with SrRuO3 does not particularly like to sinter, meaning it does not hold together well after we make the target. During use, stresses form in the target and it can begin to crack, it also does not stand up well to polishing or if loaded in the PLD chamber with set screws.

Over the years we have refine out methods to make some of the hardiest SrRuO3 target available, that being said, this is one material where we suggest considering a copper backing plate. It will make your targets last long and easier to handle if you are often moving in and out of the chamber.

Cost of Ruthenium and SrRuO3 targets

Ruthenium is expensive and the cost of it varies. This is what makes materials like SrRuO3 and CaRuO3 more expensive than other materials