摘要
Ferroelectric HfO_(2)-based materials and devices show promising potential for applications in information technology but face challenges with inadequate electrostatic control,degraded reliability,and serious variation in effective oxide thickness scaling.We demonstrate a novel interface-type switching strategy to realize ferroelectric characteristics in atomic-scale amorphous binary oxide films,which are formed in oxygen-deficient conditions by atomic layer deposition at low temperatures.This approach can avoid the shortcomings of reliability degradation and gate leakage increment in scaling polycrystalline doped HfO_(2)-based films.Using theoretical modeling and experimental characterization,we show the following.(1)Emerging ferroelectricity exists in ultrathin oxide systems as a result of microscopic ion migration during the switching process.(2)These ferroelectric binary oxide films are governed by an interface-limited switching mechanism,which can be attributed to oxygen vacancy migration and surface defects related to electron(de)trapping.(3)Transistors featuring ultrathin amorphous dielectrics,used for non-volatile memory applications with an operating voltage reduced to±1 V,have also been experimentally demonstrated.These findings suggest that this strategy is a promising approach to realizing next-generation complementary metal-oxide semiconductors with scalable ferroelectric materials.
基金
support from the National Key R&D Program of China(No.2022ZD0119002)
the National Natural Science Foundation of China(Grant Nos.62204226,62025402,62090033,92364204,92264202 and 62293522)
Major Program of Zhejiang Natural Science Foundation(Grant No.LDT23F04024F04).
