TY - JOUR
T1 - Experimental evidence of ferroelectric negative capacitance in nanoscale heterostructures
JF - Applied Physics Letters
Y1 - 2011/
A1 - Islam Khan
A1 - D. Bhowmik
A1 - P. Yu
A1 - Joo Kim
A1 - X. Pan
A1 - Ramamoorthy Ramesh
A1 - S. Salahuddin
KW - Bi-layer
KW - Capacitance
KW - Capacitance enhancement
KW - Classical limits
KW - Experimental evidence
KW - Ferroelectric materials
KW - ferroelectricity
KW - Gate oxide
KW - Heterojunctions
KW - lead
KW - Mean field theory
KW - Nano scale
KW - Nanocomposite films
KW - NanoScale Transistors
KW - nanostructured materials
KW - Nanotechnology
KW - negative capacitance
KW - Negative capacitance effect
KW - Proof of concept
KW - SrTiO
KW - Strontium alloys
KW - Strontium titanates
KW - Subthreshold slope
KW - Tuning parameter
KW - zirconium
AB - We report a proof-of-concept demonstration of negative capacitance effect in a nanoscale ferroelectric-dielectric heterostructure. In a bilayer of ferroelectric Pb(Zr0.2Ti0.8)O3 and dielectric SrTiO3, the composite capacitance was observed to be larger than the constituent SrTiO3 capacitance, indicating an effective negative capacitance of the constituent Pb(Zr0.2Ti0.8)O3 layer. Temperature is shown to be an effective tuning parameter for the ferroelectric negative capacitance and the degree of capacitance enhancement in the heterostructure. Landau's mean field theory based calculations show qualitative agreement with observed effects. This work underpins the possibility that by replacing gate oxides by ferroelectrics in nanoscale transistors, the sub threshold slope can be lowered below the classical limit (60 mV/decade). © 2011 American Institute of Physics.
VL - 99
N1 - cited By 169
ER -