Abstract:
A p-channel silicon-oxide-nitride-oxide-silicon (SONOS) flash memory device based on bulk fin shaped field effect transistor (FinFET) structure was fabricated and characterized as a highly scalable device structure. Key process steps were explained in detail and electrical characteristics were measured. The threshold voltage shift Vth was checked in the proposed device with the source/drain floating and grounded. This result means that the proposed device structure can be applicable to NAND and NOR flash memories. In this structure, program/erase times can be controlled by fin body width, which is the unique parameter of FinFET structure. In the endurance test, about 1.3 V of the Vth was kept until 104 P/E cycles. The Vth of the proposed flash memory device was extrapolated to about 0.5 V after 10 y retention. The Vth with crystal orientation of the side-channel also was checked.