52 research outputs found
Some Considerations on Tunneling Losses in Field-Effect Devices for Low-Voltage Microcontrollers
The loss power density associated with the tunneling current in a typical MOS cell with a
floating gate is evaluated for high electric-field strengths in the oxide layer. Furthermore,
problems related to oxide thickness are discussed
Evaluation of Bonding Orbitals in Amorphous Silicon by Means of the Chemical Pseudopotential Method
The chemical pseudopotential method has been used by a number of workers in order to study the
valence bands of amorphous tetrahedrally bonded semiconductors. However, various problems related
to this method are unsolved. In this paper, a theoretical formulation tending to clarify some of these.
problems is presented.
This formulation concerns bonding orbitals and is valid, in principle, for amorphous silicon
A Brief Study to Clarify Some Aspects Related to Vibrational Density of States for the Far Infrared Range in Amorphous Semiconductors
Phonon density of states of amorphous semiconductors for the far-infrared range is
examined analytically. On the basis of this formulation, optical absorption corresponding
to structural disorder is evaluated and discussed at the far-infrared range for a-Ge
and a-Si
A Brief Note on Coherent Feedback in Semiconductor Lasers
Some aspects on coherent feedback in a laser diode are investigated. In particular, weak optical feedback
is considered in the context of the feedback-induced frequency shift. In addition, the Lang-Kobayashi
equations are considered
A Discussion on the Phonon Density of States of Amorphous Germanium for the Infrared Range
A theoretical formulation for the phonon density of states of amorphous germanium in
the infrared range is proposed. This formulation is based upon the quasi-harmonic
approximation and is compared with previous results
On the Sensitivity of the Tunneling Current to Electric Field in a MOSFET with Two Gates
A theoretical model to evaluate the sensitivity of the tunneling current to the electric field
in an n-channel MOSFET with two gates is proposed. This sensitivity is calculated in a
real situation
Some Results on PIN and ITO Photodiodes
In this paper, various contributions concerning generalized photodiodes and ITO photodiodes are
reported. In particular, calculations related to the bandwidth of the equivalent circuit ot a PIN photodiode
are performed and compared to experimental considerations. In addition, an ITO structure on
a layer n-type GaAs is examined. An ITO-HEMT is also considered
A New Mathematical Model for Cluster Calculation in Tetrahedrally Bonded Amorphous Semiconductors
Tetrahedraily bonded amorphous semiconductors exhibit a structure suitable for applying the so-called
extended Hückel theory (EHT) to determine the electronic density of states by means of the cluster
calculation. In the following, a new mathematical model based on EHT is established. The results
obtained from this model have sufficient accuracy for applications and provide a useful methodology
that combines adequately with the spectrum computations. Density of valence states has been obtained
experimentally with monochromatized X-rays and the theoretical results obtained in this paper are in
good agreement with these experiments
First-Order Optical Phonon Processes in Amorphous Clusters
Optical absorption in the far infrared range for amorphous GaAs, SiC and Ge is investigated. Small
clusters in the context of dynamical disorder are considered. Average values of the absorption contributions
due to both dynamical and structural disorders are introduced. In particular, an equation for
the spectrum due to dynamical disorder in amorphous SiC is presented
Fermionic Behaviour of Excitons in Both Parabolic and Non- Parabolic Semiconductors
Abstract. We investigate satisfactorily the possible, under certain circumstances, fermionic nature of excitons in both parabolic and non-parabolic semiconductors. In this context, we discuss some key aspects dealing, on the one hand, with Fermi velocity and, on the other hand, with the particle-in-abox model. These aspects are discussed in the light of the role of excitons as bosons or fermions. Our investigation has a, say, a practical character so we may say that the method utilized here is more intuitive for the reader than some work published in the current literature
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