A novel high endurance HZO FeFET with monolayer graphene inserted in the gate oxide.

The poor endurance of hafnium oxide (HfO)-based ferroelectric field-effect transistors (FeFETs) limits their applications. From a novel perspective of ferroelectric domain engineering, we propose and fabricate a high endurance HfO-based FeFET with monolayer graphene (GR) inserted in the gate oxide for the first time. The introduction of GR between the ferroelectric (FE) layer and the interfacial layer (IL) increases the number of domains in the ferroelectric (FE) layer and reduces the electric field of the IL. Meanwhile, the low density of states (DOS) of monolayer GR suppresses the charge injection to further optimize the endurance. Experimental results show that the endurance of the GR-intercalated FeFET (GR-FeFET) exceeds 10 cycles, which is more than 2 orders of magnitude higher than that of the conventional FeFET. The gate leakage is also effectively suppressed by the GR layer. This work opens a new avenue for improvement of the endurance of FeFETs and demonstrates GR-FeFETs as potential candidates for next-generation embedded memory applications.