Imtiaz Ahmed

Purdue University | Purdue · School of Electrical and Computer Engineering

This work presents the first investigation of the SweGaN QuanFINE ultrathin GaN-on-SiC platform for the performance of surface acoustic wave (SAW) devices over 14 GHz. Frequency scaling is made possible by the absence of a thick buffer layer typical in epitaxial GaN technology. After finite element analysis (FEA) simulation to identify acoustic mod...

This paper presents a comprehensive study of the performance of Sezawa surface acoustic wave (SAW) devices in SweGaN QuanFINE ultrathin GaN/SiC platform, reaching frequencies above 14 GHz for the first time. Sezawa mode frequency scaling is achieved due to the elimination of the thick buffer layer typically present in epitaxial GaN technology. Fini...

This work presents a comprehensive comparison of switchable electromechanical transducers in an AlN/GaN heterostructure toward the goal of reconfigurable RF building blocks in next-generation ad hoc radios. The transducers’ inherent switching was achieved by depleting a 2D electron gas (2DEG) channel, allowing an RF signal launched by interdigital...

This work presents a switchable MEMS resonator in an AlN/GaN heterostructure targeted for reconfigurable RF components in next generation programmable radios. The carrier density of a 2D electron gas (2DEG) is set by a Schottky control gate out of line with the RF signal. When a negative bias voltage applied to the control gate is larger than the t...

In this work, a compact transport model has been developed for monolayer transition metal dichalcogenide channel MOSFET. The analytical model solves the Poisson's equation for the inversion charge density to get the electrostatic potential in the channel. Current is then calculated by solving the drift-diffusion equation. The model makes gradual ch...

In this paper, Capacitance-Voltage (CV) characteristics and direct tunneling gate leakage performance of InAs/AlSb Metal Oxide Semiconductor High Electron Mobility Transistor (MOS-HEMT) are investigated. 1-D coupled Schrӧdinger-Poisson equations are solved for electrostatic characterization of InAs/AlSb MOS-HEMT considering wave function penetratio...

An analytical subthreshold swing (SS) model for Cylindrical Gate-All-Around Junctionless Field Effect Transistor (CGAA JLFET) has been proposed in this work. Basically, 2D Poisson equation has been solved along the channel while assuming a parabolic potential distribution across the radial direction of the silicon channel, which in turn leads to so...

We propose a low subthreshold swing transistor architecture called Negative Capacitance Single Gate Silicon-On-Insulator Tunneling Field Effect Transistor (NC-SG-SOI-TFET) and present an analytical model to characterize its performance. Electrostatic potential distribution and electric field intensity in the channel region are obtained by solving t...

In this paper, we propose an analytical 2D model to calculate the potential in the channel for all types of double gate junctionless field effect transistors (DG JLFETs), which is valid in the subthreshold regime. Model is derived by solving 2D Poisson’s equation along the channel while assuming a cubic potential distribution across the silicon thi...

We propose a physically based analytical compact model to calculate Eigen energies and Wave functions which incorporates penetration effect. The model is applicable for a quantum well structure that frequently appears in modern nano-scale devices. This model is equally applicable for both silicon and III-V devices. Unlike other models already avail...

This paper reports complete Capacitance-Voltage (CV) characterization of InAsySb1−y Quantum Well Field Effect Transistor (QWFET) along with an analysis of ballistic transport performance. 1-D coupled Schrodinger-Poisson equations are solved for electrostatic performance analysis of QWFET considering wave function penetration and strain effects. Dep...

We investigated Capacitance-Voltage (C-V) characteristics of the Depletion Mode Buried Channel InGaAs/InAs Quantum Well FET by using Self-Consistent method incorporating Quantum Mechanical (QM) effects. Though the experimental results of C-V for enhancement type device is available in recent literature, a complete characterization of electrostatic...

Capacitance-Voltage (C-V) & Ballistic Current-Voltage (I-V) characteristics of Double Gate (DG) Silicon-on-Insulator (SOI) Flexible FETs having sub 35nm dimensions are obtained by self-consistent method using coupled Schrodinger-Poisson solver taking into account the quantum mechanical effects. Although, ATLAS simulations to determine current and o...

In this work, we propose an explicit analytical equation to show the variation of top gate threshold voltage with respect to the JFET bottom gate voltage for a Flexible Threshold Voltage Field Effect Transistor (Flexible-FET) by solving 2-D Poisson's equation with appropriate boundary conditions, incorporating Young's parabolic approximation. The p...

In this paper, Capacitance-Voltage (C-V) characteristics and direct tunneling (DT) gate leakage current of antimonide based surface channel MOSFET were investigated. Self-consistent method was applied by solving coupled Schrödinger-Poisson equation taking wave function penetration and strain effects into account. Experimental I-V and gate leakage c...