Organic CuTCNQ non-volatile memories for integration in the CMOS backend-of-line: Preparation from gas/solid reaction and downscaling to an area of 0.25 μm2

CuTCNQ is an organic semiconductor charge transfer material that allows the realization of non-volatile cross-bar memory arrays with conductivity switching. In this work, we present a simple preparation method of this organic memory material, compatible with industrial processing and downsizing of the memory cells. CuTCNQ nanowires were prepared on Cu by a solid–gas phase corrosion reaction between the metal and hot TCNQ gas at low pressure. Surface coverage increased with reaction time and temperature. Cu/CuTCNQ/Al cross-point cell arrays with memory areas of 0.01 mm2 exhibited I–V curves with ON/OFF current ratios of about 10. Further downscaling of the CuTCNQ nanowire memory elements was successful on top of 0.25 μm2 copper-filled vias. Corresponding memories achieved ON/OFF current ratio of about 100. This is, to our knowledge, the first report on downscaling of organic memories to this size.