Structural and electrical properties of a high-k SmAlO3 charge trapping flash memory

In this study, we proposed the Al/Al2O3/SmAlO3/SiO2/Si flash memory devices using high-k SmAlO3 film as a charge trapping layer and high-k Al2O3 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 SmAlO3 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 104 s). In addition, the charge trap centroid and charge trap density were extracted by constant current stress method.

► We developed the MOHOS memory using a SmAlO3 film as a charge trapping layer and an Al2O3 material as a blocking oxide. ► The SmAlO3 MOHOS memory exhibited a large hysteresis memory window (2.61 V) and smaller charge loss (7.1%). ► The Al/Al2O3/SmAlO3/SiO2/Si structure is a promising candidate for flash memory device application.