Epitaxial fabrication and memory effect of ferroelectric LiNbO_3 film/AlGaN/ GaN heterostructure

摘要

A metal-ferroelectric-semiconductor structure was fabricated epitaxially by depositing a LiNbO_3 film on the surface of the AlGaN/GaN template with two dimensional electron gas (2DEG). The capacitance-voltage characteristics were studied. Counterclockwise memory windows could be observed clearly. The size of the window first increased with increasing forward bias (V_(max)) and reached a maximum of 2.5 V when V_(max) = 6 V. This was attributed to the switchable ferroelectric polarization modulating on 2DEG. When V_(max) exceeded 6 V, the window decreased due to electron injection. These results indicated that ferroelectric films combined with AlGaN/GaN would hold promise for next-generation memory devices.