The dominant factors affecting the memory characteristics of (Ta_2O_5)_x(Al_2O_3)_(1-x) high-k charge-trapping devices

摘要

The prototypical charge-trapping memory devices with the structure p-Si/Al_2O_3/(Ta_2O_5)_x (Al_2O_3)_(1-x)/Al_2O_3/Pt(x = 0.5, 0.3, and 0.1) were fabricated by using atomic layer deposition and RF magnetron sputtering techniques. A memory window of 7.39 V with a charge storage density of 1.97 × 10~(13)cm~(-2) at a gate voltage of ± 11 V was obtained for the memory device with the composite charge trapping layer (Ta_2O_5)_(0.5)(Al_2O_3)_(0.5). All memory devices show fast program/erase speed and excellent endurance and retention properties, although some differences in their memory performance exist, which was ascribed to the relative individual band alignments of the composite (Ta_2O_5)_x(Al_2O_3)_(1-x)with Si.