Thermodynamic control the self-assembled formation of vertically aligned nanocomposite thin film

Abstract

ABSTRACT Emergent exotic phenomena in the self-assembled process of vertically aligned nanocomposite (VAN) thin film remain under intensive studies. Insight exploration on the self-assembled formation from the combination of two different phases of materials is not only important to optimize the physical properties yields from those combined materials, but also open up a new avenue to discover new materials with the VAN system. In this work, the thermodynamic control of the self-assembled formation of BiFeO3-CoFe2O4 (BFO-CFO) VAN thin film has been confirmed by studying the effects of substrate temperature during the growth process by pulsed laser deposition (PLD) technique. The structural examination results on the samples, which were growing with various substrate temperatures highlight the importance of the thermodynamic factor to control the crystalline structure of BFO phase and CFO pillar size, which then affect the physical properties and further its practical applications. For instance, we can control the size of the CFO pillar using a temperature substrate to find appropriate spin magnetic switching in the CFO pillar for memory device applications. This study also sheds light on the relationship between thermodynamics and elastic strain energy on the formation of self-assembled matrix-pillars of the BFO-CFO VAN which is important for device fabrication.