An 'Electrolithic' memory cell for ultra-high density data storage: Demonstration with high-aspect-ratio nanometer-sized holes

Abstract

The exponential growth in digital data requires storage technologies with ever increasing bit densities at reduced costs. In this paper, we demonstrate the feasibility of a novel memory concept where information is stored in the form of thickness-modulated electrochemically deposited metal multilayers. Specifically, using a citrate-based Cu-Ni plating bath and memory holes approaching technologically relevant dimensions (80 nm diameter, 1 µm depth), we show that data stored as modulated Ni|Cu stacks can be controllably written and retrieved. The results shown in this paper would directly translate to a bit density of ≈1 Gbit/mm2, on par with what hard disk drives achieve today. We further discuss the path to achieve 1 Tbit/mm2 and evaluate other performance characteristics in view of the requirements for secondary storage applications.