IEEE transactions on very large scale integration (VLSI) systems

Semiconductor nanowires have attracted extensive interest as one of the best-defined classes of nanoscale building blocks for the bottom-up assembly of functional electronic and optoelectronic devices over the past two decades. The article provides a comprehensive review of the continuing efforts in exploring semiconductor nanowires for the assembly of functional nanoscale electronics and macroelectronics. Specifically, we start with a brief overview of the synthetic control of various semiconductor nanowires and nanowire heterostructures with precisely controlled physical dimension, chemical composition, heterostructure interface, and electronic properties to define the material foundation for nanowire electronics. We then summarize a series of assembly strategies developed for creating well-ordered nanowire arrays with controlled spatial position, orientation, and density, which are essential for constructing increasingly complex electronic devices and circuits from synthetic semiconductor nanowires. Next, we review the fundamental electronic properties and various single nanowire transistor concepts. Combining the designable electronic properties and controllable assembly approaches, we then discuss a series of nanoscale devices and integrated circuits assembled from nanowire building blocks, as well as a unique design of solution-processable nanowire thin-film transistors for high-performance large-area flexible electronics. Last, we conclude with a brief perspective on the standing challenges and future opportunities.

Nanowire Electronics: From Nanoscale to Macroscale

INTERSUBBAND RELAXATION IN GaAs/Al x Ga 1-x As QUANTUM WELL STRUCTURES

Two concentration ranges of silicon doping in MBE-grown GaAs films have been investigated in some detail. In lightly doped films, with a free-electron concentration of ≈1016cm−3, low-temperature photoluminescence spectra have been analysed to develop a model to account for spectral features previously attributed to Ge and Si acceptor levels. In heavily doped films, a maximum free-electron concentration of ≈7×1018 cm−3 has been obtained, which is only rather weakly dependent on growth conditions and the nature of the arsenic species (As2 or As4). Transmission electron microscopy has shown that no significant precipitation effects occur when higher Si fluxes are used but there is evidence for autocompensation. The maximum PL intensity (300 K) is found at a lower free electron concentration then with Sn-doped films, and is more sharply peaked, but there is no evidence for an anomalous Moss-Burstein shift.

Silicon doping of MBE-grown GaAs films

Physics of Semiconductor Devices. S. M. Sze. Interscience (Wiley), New York, 1969. xvi + 814 pp., illus. $19.95

The authors have theoretically investigated transient response of electrons in bulk Wurtzite GaN at 300K using one particle monte-carlo method The relevant lattice scattering mechanisms like deformation potential acoustic phonons, polar optical phonons, impurity and intervalley phonon scatterings are incorporated in the Boltzmann transport equation which is then solved to obtain the transient response characteristics The transient response characteristics at 300K show that higher peak drift velocities are obtained at higher field values The velocity — field characteristics for electrons at 300K exhibit a negative differential resistance (NDR) effect

Study of transient response characteristics of electrons in GaN by Monte Carlo method

The paper numerically suggested the examination of potential energy profile at multibarrier system by using the Airy function formalism and consequently we derived the various transmission properties like transmission coefficient, reflection coefficient, energy and some other substantial physical parameters are analysed at different values of internal bias across the semiconductor arrangement.

Advanced pioneer approach to various properties and significant parameters in special semiconductor arrangement

Analytical innovation of static characteristics for novel AlGaN/Ga14N15N superlattice MOSFET

Studies are carried out to design and optimize the performance of next-generation dual-material double-gate (DMDG) P-channel TFET for low power digital application using Si as the channel material and SiO2 as gate dielectric The channel length of the device has been varied in the range of 20–30 nm The DC properties and performance of DMDG TFET have been compared with that of a dual-material single-gate (DMSG) TFET with respect to low power application of the device 2D Poisson’s equation is solved to obtain the band diagrams for both on and off states, the electric field profile and surface potential of the device The performance parameters of the optimized DMDGTFET such as on–off current ratio and subthreshold swing (SS) are compared with those of DMSG TFET The results show that the DC properties of next-generation DMDG TFET excel those of DMSG TFET for a channel length of 20 nm The on–off current ratio in DMDG TFET is 218 × 104 while the same in its DMSG counterpart is one order of magnitude lower The values of SS in DMDG and DMSG TFET are found to be 201 and 36 mV/decade, respectively

Optimization of a Dual-Material Double-Gate TFET for Low Power Digital Application

AlGaN/GaN-based DSG-MOSFET is upcoming model of MOSFET. In this paper, comparative study of DSG-MOSFET $\mathrm{V}_{\mathrm{s}}$ normal MOSFET and analyzed the performance of DSG-MOSFET. The main features of it are there is negotiable barrier between source and drain so current moves more freely and current is more than normal MOSFET. As if current is more than normal MOSFET then crack length is minimum in DSG-MOSFET.

Aniruddha Ghosal

Papers

Study of transient response characteristics of electrons in GaN by Monte Carlo method

Advanced pioneer approach to various properties and significant parameters in special semiconductor arrangement

Analytical innovation of static characteristics for novel AlGaN/Ga14N15N superlattice MOSFET

Optimization of a Dual-Material Double-Gate TFET for Low Power Digital Application

Comparative Investigation of DSG-MOSFET and Some analysis on its Performance