Modeling the MOSFET's Inversion Layer and Its Universal Mobility: A New Experimental Method

<div>We formulate a simple, yet accurate, model for a non-uniform mobile charge density ρ(z) giving rise to a mean potential Ψ* across an inversion layer of finite extent, which we measure by means of a novel, sensitive, experimental method involving nulls of harmonic distortion components (D2 ≈ D3 ≈ 0) of the drain current under sinusoidal excitation below saturation. We thus establish analytically and experimentally, that the low-field, "universal" effective mobility µ_eff varies as ~(E*_T)^-1/3for transversal fields E_T*= <b>-</b>(1/ε_si)<b>·</b>[ɳQ_i + Q_b] <b>≤ </b>0.5 MV/cm, wherein ɳ varies continuously between 1/2 and 1/3. We also establish and observe that the higher order, derivative, parameter θ_T quantifying µ_eff’s modulation by E*_T varies as ~(E*_T)^-5/3 under laminar flow conditions, thereby further corroborating the foregoing effects and interpretations thereof.</div>

Modeling the MOSFET's Inversion Layer and Its Universal Mobility: A New Experimental Method

<div>We formulate a simple, yet accurate, model for a non-uniform mobile charge density ρ(z) giving rise to a mean potential Ψ* across an inversion layer of finite extent, which we measure by means of a novel, sensitive, experimental method involving nulls of harmonic distortion components (D2 ≈ D3 ≈ 0) of the drain current under sinusoidal excitation below saturation. We thus establish analytically and experimentally, that the low-field, "universal" effective mobility µ_eff varies as ~(E*_T)^-1/3for transversal fields E_T*= <b>-</b>(1/ε_si)<b>·</b>[ɳQ_i + Q_b] <b>≤ </b>0.5 MV/cm, wherein ɳ varies continuously between 1/2 and 1/3. We also establish and observe that the higher order, derivative, parameter θ_T quantifying µ_eff’s modulation by E*_T varies as ~(E*_T)^-5/3 under laminar flow conditions, thereby further corroborating the foregoing effects and interpretations thereof.</div>

Conservation Laws at Physical Origins of Universal Mobility in MOSFET Inversion Layers in Consilience with River Flow in a Gravitational Field

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be analogous to a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We formulate an accurate model for a non–uniform mobile charge density giving rise to a mean potential<i> </i>across an inversion layer of finite extent<i>,</i> which we measure by a sensitive experimental method …

Conservation Laws at Physical Origins of Universal Mobility in MOSFET Inversion Layers in Consilience with River Flow in a Gravitational Field

The salient properties of charge flow (or current) along the MOSFET’s inversion layer are shown to be analogous to a river’s flow in a gravitational potential field, insofar as both are fundamentally governed by energy conservation principles, and their laminar and turbulent conditions determined by friction losses at shallow depths. We formulate an accurate model for a non–uniform mobile charge density giving rise to a mean potential<i> </i>across an inversion layer of finite extent<i>,</i> which we measure by a sensitive experimental method …

Asymmetric, mixed-valence molecules for spectroscopic readout of quantum-dot cellular automata

Mixed-valence compounds may provide molecular devices for an energy-efficient, low-power, general-purpose computing paradigm known as quantum-dot cellular automata (QCA). Multiple redox centers on mixed-valence molecules provide a system of coupled quantum dots. The configuration of mobile charge on a double-quantum-dot (DQD) molecule encodes a bit of classical information robust at room temperature. When arranged in non-homogeneous patterns (circuits) on a substrate, local Coulomb coupling between molecules enables information processing. While single-electron transistors (SETs) and single-electron boxes (SEBs) could provide low-temperature solutions for reading the state of a 1-nm-scale molecule, we propose a room-temperature read-out scheme. Here, DQD molecules are designed with slightly dissimilar quantum dots. Ab initio calculations show that the binary device states of an asymmetric molecule have distinct Raman spectra. Additionally, the dots are similar enough that mobile charge is not trapped on either dot, allowing device switching driven by the charge configuration of a neighbor molecule. A technique such as tip-enhanced Raman spectroscopy (TERS) could be used to detect the state of a circuit comprised of several QCA molecules.

Highly Conductive Ceramics with Multiple Types of Mobile Charge Carriers

Functional ceramic materials are of interest in many applications due to their structural and chemical richness and the huge range of physical properties that can be generated and modified by the control of the former (electrical conductivity, thermo-mechanical properties, dielectric, piezoelectric, ferroelectric properties, etc [...]