Structural and electrical properties of a high-k SmAlO ₃ charge trapping flash memory

In this study, we proposed the Al/Al ₂O ₃/SmAlO ₃/SiO ₂/Si flash memory devices using high-k SmAlO ₃ film as a charge trapping layer and high-k Al ₂O ₃ film as a blocking layer. The structural and morphological features of these films were explored by X-ray diffraction, X-ray photoelectron spectroscopic and atomic force microscopy. The SmAlO ₃ flash memory devices annealed at 800°C showed excellent electrical properties, such as a large memory window of ∼2.61 V (measured at a sweep voltage range of ±5 V) and a small charge loss of ∼7.1% (measured time up to 10 ⁴ s). In addition, the charge trap centroid and charge trap density were extracted by constant current stress method.