Effect of Argon Plasma- Induced Buckling on Coercivity of Permalloy Thin Films on PDMS

The presence of stress/strain in thin films grown on compliant substrates such as polydimethylsiloxane (PDMS) can lead to a buckling phenomenon that is heavily influenced by the moduli and thickness of the film and the substrate. Thermally-induced stress/ strain in the film is the most common cause of buckle formation. The periodicity, orientation, and overall buckling geometry can be controlled through other means and is the subject of this investigation. Here, the authors report on the effect of argon plasma treatment conditions on isotropic buckle formation in 10 and 50 nm thin permalloy (Py, Ni₈₀Fe₂₀) films, grown on PDMS substrates via sputter deposition. An increase in coercivity was detected when the substrates were functionalized, scaling with Ar plasma power. This work paves the way for the design and optimization of thin flexible electronic sensing devices and improved understanding of   stress and strain impacts on magnetic properties.