hascloud.blogg.se - Near equilibrium green function quantumwise

Thus next generation transistor which can offer sub-60 mV/decade subthreshold slope is in high demand as it may restore the energy efficient constant-field scaling by enabling the supply voltage reduction below 0.6 V. As a result, the semiconductor industry has been forced to adopt the energy-inept constant-voltage scaling practice for a decade with a value close to 0.6 V. This OFF-state current leads to significant static power dissipation, which is very crucial for battery operated modern hand-held electronic gadgets (cell phone, tablet etc). It is worth noting that the limited value of SS arises from the thermionic emission of the carriers from the source to the channel in a conventional MOSFET. Since the subthreshold slope (SS) of a MOSFET does not scale with feature size (rather degrades due to drain-induced-barrier-lowering (DIBL) effect) and limited to minimum value of 60 mV/decade, the OFF-current ( I OFF) increases exponentially with V T reduction. A V D scaling also calls for an equal scaling of the threshold voltage ( V T) to preserve the ON-current ( I ON). According to this theory, the power density remains constant over technology nodes if both the dimension and supply voltage ( V D) are scaled by the same factor (known as constant-field scaling). Our study shows that monolayer GeSe-TFET is scalable till 8 nm while preserving ON/OFF current ratio higher than 10 4.ĭennard’s scaling theory 1, 2 has acted as a guideline for the semiconductor industry to miniaturize the metal oxide semiconductor (MOS) technology in order to comply with the Moore’s law 3.

Keeping the OFF-current fixed at 10 pA/μm we investigate different static and dynamic performance metrics (ON current, energy and delay) under three different constant-field scaling rules: 40, 30 and 20 nm/V.

p hamiltonian to calculate self-consistent solution of the transport equations within the non-equilibrium Green’s function formalism and the Poisson’s equation based electrostatic potential.

We find that the complex band wraps itself within the conduction band and valence band edges and thus signifies efficient band to band tunneling mechanism. We first study the electronic band structure by regular and hybrid density functional theory and develop two band k

In this work we employ ballistic quantum transport model to assess the intrinsic performance limit of monolayer GeSe-TFET. Recently discovered atomically thin GeSe, a group IV mono-chalcogenide, can be a potential candidate owing to its direct electronic band gap and low carrier effective mass. Selection of appropriate channel material is the key to design high performance tunnel field effect transistor (TFET), which promises to outperform the conventional metal oxide semiconductor field effect transistor (MOSFET) in ultra-low energy switching applications.