Advanced impurity trap memory with atomic-scale Ti impurities on LaAlO3: Evidence for the origins of enhanced memory performance

We investigated advanced impurity trap memory (ITM) with atomic-scale Ti impurities on LaAlO3. Our ITM showed excellent memory characteristics, including a memory window (MW) of 5 V under +12 V/−10 V, ∼44% retained charge in 10 yr retention at 85 °C, and endurance without MW degradation up to 104 cycles. To understand the origins of these enhanced characteristics, we conducted various physical analyses. Our results confirmed that the incorporation of ultrathin LaAlO3, featuring both thermodynamic stability for diffusion barrier of Ti and favorable energy band structure together with high dielectric constant for bandgap engineering of tunnel oxide, is responsible for enhanced performance.

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