Porous Si and Al2O3 have been used extensively as negative templates to form ferroelectric nanostructures by various methods. However, in order to expose the ferroelectric materials ready for application, it is necessary to etch away the templates. Damage to the nanostructures can occur during etching. To solve this problem, hydrothermal ZnO nanoarrays (ZNAs) have been employed as a positive template for ferroelectric BiFeO3 (BFO). Nevertheless, the fabrication of the ferroelectric shell in a basic hydrothermal environment resulted in dissolution of ZnO nanostructures. Therefore, sputtering was chosen to preparing the BFO shell. The result is a BFO/ZnO core/shell heterostructure.
http://nanotechweb.org/cws/article/lab/45378