In this research, we investigated the digital/analogoperation utilizing ferroelectric nondooped HfO 2 (FeND-HfO 2 ) as a blocking layer (BL) in the Hf-based metal/oxide/nitride/oxide/Si (MONOS) nonvolatile memory (NVM), so called FeNOS NVM. The Al/HfN 0.5 / HfN 1.1 /HfO 2 /p-Si(100) FeNOS diodes realized small equivalent oxide thickness (EOT) of 4.5 nm with the density of interface states (D it ) of 5.3 10 eV -1 cm -2 which were suitable for high-speed and low-voltage operation. The flat-band voltage (V FB ) was well controlled as 80-100 mV with the input pulses of 3 V/100 ms controlled by the partial polarization of FeND-HfO 2 BL at each 2-bit state operated by the charge injection with the input pulses of +8 V/1-100 ms.