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The electrical properties of Cr-SrTiO"3 films deposited on p-Si(100) substrates are investigated for application to a new type of charge-trap flash memory, named ReCTF (ReRAM+CTF). The Cr-SrTiO"3 film used as a switch in a ReCTF device has a complete cubic perovskite structure with a (200) crystallographic orientation. By means of current-voltage (I-V) and capacitance-voltage (C-V) analyses, we found that it exhibited electric-field-induced threshold switching characteristics and there were no trapping effects. In this study, we investigated how the retention characteristics of the ReCTF device can be improved without any special processes by applying an optimized Cr-SrTiO"3 film.

The paper presents the passivation effect of post-annealing gases on the negative bias temperature instability of metal/silicon-oxide/silicon-nitride/silicon-oxide/silicon (MONOS) capacitors. MONOS samples annealed at 850 °C for 30 s by a rapid thermal annealing (RTA) are treated by additional annealing in a furnace, using annealing gases N 2 and N 2 –H 2 (2% hydrogen and 98% nitrogen gas mixture) at 450 °C for 30 min. MONOS samples annealed in an N 2 –H 2 environment are found to have lowest oxide trap charge density shift, Δ N ot = 8.56 × 10 11 cm −2 , and the lowest interface-trap density increase, Δ N it = 4.49 × 10 11 cm −2 among the three samples as-deposited, annealed in N 2 and N 2 –H 2 environments. It has also been confirmed that the same MONOS samples have the lowest interface-trap density, D it = 0.834 × 10 11 eV −1 cm −2 , using small pulse deep level transient spectroscopy. These results indicate that the density of interface traps between the silicon substrate and the tunneling oxide layer are significantly reduced by the additional furnace annealing in the N 2 –H 2 environment after the RTA.