Fabrication of TiO2 Memristive Arrays by Step and Flash Imprint Lithography

Abstract

Identical patterns and characteristics of sub-100 nm TiO2-based memristive systems on 4 inch silicon substrates were demonstrated using Step and flash imprint lithography (SFIL). SFIL is a nanoimprint lithography technique that offers the advantagess of a high aspect-ratio, reliable nanopatterns, and a transparent stamp that can be used to facilitate overlay techniques. The overlay process from the alignment system in IMPRIO 100 was appropriate for the fabrication of nanoscale crossbar arrays in this study. High-density crossbar arrays that consisted of TiO2 resistive switching material that was sandwiched between Pt electrodes with a width of 80 nm and a half-pitch of 100 nm were in turn replicated through successive imprinting and etching processes. The use of the direct metal etching process enhanced the uniformity of the TiO2/Pt interface. The electrical property of the crossbar arrays showed the bipolar switching behavior that resulted in the application of the nonvolatile resistive memory.