Effect of postdeposition annealing on the structural and electrical characteristics of Yb_2TiO_5 charge trapping layers

摘要

In this letter, we proposed a metal-oxide-high-k-oxide-silicon-type (MOHOS) memory structure incorporating a high-k Yb_2TiO_5 charge trapping layer and the subsequent postdeposition annealing treatment. The effect of postdeposition annealing on the structural properties of Yb_2TiO_5 charge trapping layers was explored by x-ray diffraction, transmission electron microscopy, and x-ray photoelectron spectroscopy. The Yb_2TiO_5 MOHOS-type device annealed at 800℃ exhibited a larger memory window of 2.8 V and a smaller charge loss of 10% than did those prepared at other annealing temperatures. This outcome is attributed to the higher probability for trapping the charge carrier due to the formation of a well-crystallized Yb_2TiO_5 structure and a thin low-k interfacial layer.