Influence of adhesion layer and sputter gas pressure on structural and magnetic properties of Co/Pt multilayers

Co/Pt multilayers (MLs) are standard systems for perpendicular anisotropy layered thin films. The use of a specific underlayer, sometimes in combination with additional, very thin adhesion layers, is a common practice to define a crystalline texture for the ML on amorphous substrates. In addition, the sputter gas pressure during deposition can be used to tune the lateral heterogeneity and laminate order, which strongly affect the magnetic behavior of the system. However, the precise interplay between adhesion and sputter gas pressure, especially for the seed layer, is often neglected.

In this context, we will discuss the impact of the underlayers on the structural and magnetic properties of the Co/Pt ML system. We will emphasize the influence of an adhesion layer on the whole system and combine this with a systematic and separate variation of the sputter deposition pressure of Pt seed and Co/Pt ML. Carefully tuning these parameters enables us to exert a high degree of control on the structure of these systems, with characteristics ranging from continuous thin films to isolated grain structures.