Nonvolatile memory properties in ZnO-based thin-film transistors with polymer ferroelectric and thin buffer layer

摘要

We report the fabrication of ZnO non-volatile memory thin-film transistors (NVM-TFTs) with thin poly(vinylidene fluoride/trifluoroethylene)[P(VDF-TrFE)] ferroelectric layer and thin Al_2O_3 buffer layers. When our memory TFT has a thin Al_2O_3 layer inserted between P(VDF-TrFE) and ZnO channel: 5 nm, 10 nm and 20 nm Our NVM-TFT operates on glass substrates under low voltage write-erase (WR-ER) pulse of ±20 V with high field effect mobilities of 0.6-1 cm~2/Vs. The device with the Al_2O_3 layer shows much longer retention properties over 10~4 s than the other without buffer. Depending on the thickness of buffer, our NVM-TFT displays maximum memory window of ～20 V and also exhibits WR-ER current ratio of 4×10~2.