ABSTRACTFerroelectric materials such as BaTiO3 have been studied for emerging
non-volatile memory applications. However, most of the previous work has been
focused on this material when it was deposited on insulting oxide substrates
such as SrTiO3. Unfortunately, this substrate is not suitable for
CMOS-based microelectronics applications. This motivated us to carry out the
present work. We have studied the resistive switching behavior in
BaTiO3/La0.7Sr0.3MnO3 (BTO/LSMO)
heterostructures integrated with semiconducting substrates Si (100) using
MgO/TiN buffer layers by pulsed laser deposition. Current-Voltage (I-V)
measurements were conducted on BTO (500nm)/LSMO (25nm) devices at 200K. We have
observed a broad hysteresis in forward and reverse voltage sweeps which is an
important property for memory applications. Secondly, the
RON/ROFF ratio is estimated at ∼ 150,
consistent with the reported numbers (30-100) in the literature. Thirdly, the
device is stable at least up to 50 cycles. However, we found that hysteretic
behavior was suppressed upon oxygen annealing of the device at 1 atmospheric
pressure, 200° C for 1hr, inferring the important role of
oxygen vacancies in the resistive switching behavior of BTO/LSMO device. Future
work will focus on investigating the correlation between ferroelectricity and
resistive switching in these devices using local probe technique piezo force
microscopy (PFM) technique.
The Role of Defects in the Resistive Switching Behavior
of Ta2O5-TiO2-Based Metal–Insulator–Metal (MIM) Devices
for Memory Applications