Professor Balandin's Nano-Device
Laboratory (NDL) research group
is engaged in physics-based device modeling and computer
simulation of electronic devices. Using both in-house built simulation
tools and commercial software NDL members handle state-of-the-art
conventional devices as well as alternative technology device
prototypes: from vertical MOSFETs to quantum logic gates. Apart
from research benefits the use and working knowledge of the best available
commercial software packages is intended to help
NDL alumni in job search. The modeling work in NDL is closely corellated with
the group's experimental activities described HERE.
NDL has a history of research cooperation
with some of the manufactures of the device simulation software. Our
partners include researchers of the CFD
Research Corporation, one of the leading device simulation
tool developers in US. The joint projects with CFD Research Corporation
involved acoustic phonon spectrum simulation in semiconductor
nanostructures and were funded by the US AFOSR (see
the project details). CFD-ACE+
package, the most advanced computational fluid dynamics
and multi-physics software tool offered by CFD Research Corporation,
is available for students and postdoctoral researchers affiliated
with NDL. This software package enables coupled simulations of
fluid, thermal, chemical, biological, electrical and mechanical
phenomena. It is used by the semiconductor, biotech and aerospace
Figure 1. Holes current distribution after beginning of source-drain breakdown.
Another software package available
at NDL is ISE TCAD developed by the Integrated
Systems Engineering. Specifically, NDL members use
to simulate electrical, thermal, and optical characteristics
of semiconductor devices. It is one of the leading device simulators,
which handles 1D, 2D, and 3D geometries, mixed-mode circuit simulation
with compact models, and numerical devices. It contains a comprehensive
set of physical models that can be applied to all relevant types
of semiconductor devices and operation conditions. DESSIS is also
used to evaluate and understand how a device works, optimize devices,
and extract SPICE models and statistical data early in the development
cycle. Figure 1 shows electrical current distribution in GaAs
MESFET simulated using DESSIS.
another simulation tool available at NDL, is an interactive environment
for modeling and simulating scientific and engineering problems
based on partial differential equations (PDEs)-equations that
are the fundamental basis for the laws of science. FEMLAB's multi-physics
feature allows one to simultaneously model any combination of
phenomena. FEMLAB's graphical user interface includes functions
for CAD modeling, physics or equation definitions, automatic mesh
generation, equation solving, visualization, and post-processing.
FEMLAB is used by NDL group members for simulation heat flow in
GaN/AlGaN heterostructure field-effect transistors (HFETs) in
the project supported
by ONR. Figure 2 shows temperature distribution in GaN/AlGaN HFET structure
obtained with the help of FEMLAB.
Figure 2. Temperature rise profile
in the doped channel GaN/AlGaN HFET
on SiC substrate.
Results are after Filippov
and Balandin, Proceed of NanoTech, Vol.3, pp. 333-336, 2003
In addition to the device simulation
tools described above, NOMAD group and EE Department offer access
to and courses on the use of Cadence CAD tools for CMOS integrated
circuit design, layout and verification. More information on Cadence
CAD tools in UCR can be found HERE.
Figure 3. Research Associate Dr. Valentin Turin is modeling performance
degradation of GaN-based transistors due to self-heating.
Nano-Device Laboratory, 2003.
More information on the projects
currently under way in the Nano-Device Laboratory (NDL) can be
To join NDL as a graduate student or postdoctoral research visit
the web-page HERE.
To learn more about course offering in the field of Materials,
Devices and Circuits visit the web-page HERE.