1T memory cell based on PVDF-TrFE field effect transistor

Interest in vinylidene fluoride (VDF) co-polymer with trifluorethylene (TrFE) P(VDF-TrFE) as ferroelectric material for memory application is driven by the prospect of having low cost and low operating voltage devices integrated on silicon and, at long term, migrate on flexible substrates. Some previous studies reported FET design using copolymers [1-8] but none of these structures were fully integrated on silicon wafers into a quasi-standard MOSFET fabrication process. We present for the first time the integration of a P(VDF-TrFE) (70%-30%) layer into a standard n-MOS transistor gate stack through a conventional semiconductor technology. This allows us to achieve a one-transistor (IT) Non Volatile Memory (NVM) cell. The operation voltage required for the 100nm organic ferroelectric thickness is less than 12V and a retention time ranging from few hours to few days is reported. © 2008 Materials Research Society.