Effect of material selection on bonding interface for integrating epitaxial spintronic devices by Three-dimensional (3D) integration technology

摘要

Three-dimensional (3D) integration technology based on wafer bonding and backside silicon removal processes,[1] which can stack epitaxial multilayer device on polycrystalline electrode vertically, is a promising technology not only for utilizing epitaxial current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) device for ultrahigh-density hard disk drives (HDDs) read head sensor,[2] but also for 3D stacking of epitaxial magnetic tunneling junction (MTJ) in ultrahigh-density MRAM. [3] In this study, we investigated bonding interface condition dependence on different capping materials for direct wafer bonding processing.