1 |
Device-Circuit Co-Design Employing Phase Transition Materials for Low Power ElectronicsAhmedullah Aziz (7025126) 12 August 2019 (has links)
<div>
<div>
<p>Phase
transition materials (PTM) have garnered immense interest in concurrent
post-CMOS electronics, due to their unique properties such as - electrically
driven abrupt resistance switching, hysteresis, and high selectivity. The phase
transitions can be attributed to diverse material-specific phenomena, including-
correlated electrons, filamentary ion diffusion, and dimerization. In this
research, we explore the application space for these materials through
extensive device-circuit co-design and propose new ideas harnessing their unique
electrical properties. The abrupt transitions and high selectivity of PTMs
enable steep (< 60 mV/decade) switching characteristics in Hyper-FET, a
promising post-CMOS transistor. We explore device-circuit co-design methodology
for Hyper-FET and identify the criterion for material down-selection. We evaluate
the achievable voltage swing, energy-delay trade-off, and noise response for
this novel device. In addition to the application in low power logic device,
PTMs can actively facilitate non-volatile memory design. We propose a PTM
augmented Spin Transfer Torque (STT) MRAM that utilizes selective phase
transitions to boost the sense margin and stability of stored data,
simultaneously. We show that such selective transitions can also be used to
improve other MRAM designs with separate read/write paths, avoiding the possibility
of read-write conflicts. Further, we analyze the application of PTMs as
selectors in cross-point memories. We establish a general simulation framework for
cross-point memory array with PTM based <i>selector</i>.
We explore the biasing constraints, develop detailed design methodology, and
deduce figures of merit for PTM selectors. We also develop a computationally
efficient compact model to estimate the leakage through the sneak paths in a
cross-point array. Subsequently, we present a new sense amplifier design utilizing
PTM, which offers built-in tunable reference with low power and area demand.
Finally, we show that the hysteretic characteristics of unipolar PTMs can be
utilized to achieve highly efficient rectification. We validate the idea by demonstrating
significant design improvements in a <i>Cockcroft-Walton
Multiplier, </i>implemented with TS
based rectifiers. We emphasize the need to explore other PTMs with high
endurance, thermal stability, and faster switching to enable many more
innovative applications in the future.</p></div></div>
|
Page generated in 0.0244 seconds