A Method to Measure Polarization Signal of Nanoscale One-Transistor-One-Capacitor Ferroelectric Memory

This study investigates the properties of a onetransistor- one-capacitor (1T1C) device that includes a transistor and ferroelectric random access memory (FeRAM) at the nanoscale. The hysteresis characteristics are presented. A simultaneous measurement of writing and reading was used. A difference was observed between the forward and reverse transconductance (gm) −V_G curves, and the reason can be explained by the relationship between the operating voltage and coercive voltages. According to the relationship between gm and polarization, the polarization signal can be obtained using gm at the nano-scale. The remnant polarization of the 1T1C device per unit ferroelectric-layer area was confirmed by the polarization value of FeRAM via the Positive Up Negative Down method. Finally, the P–V loops obtained using gm values with different measurement ranges are also reported.