Mechanical Simulator and Process Analysis Tools
Mizuho Information & Research Institute, Inc. Micro-Electro-Mechanical Systems, Science and Technology
Yasuroh Iriye, Associate General Manager;
Atsushi Sato, Senior Consultant; andTakuya Iwasaki, Ph.D., Chief Consultant
The process analysis tools are used to create device
structures, as well as to study mask layout and process
flow design. Three-dimensional device structuresdeveloped with this tool can be imported into themechanical simulator described above. The process
analysis tools include the following functions.

In the previous issue of the MICROMACHINEmagazine (May 2005 issue), Hiroyuki Fujita, theproject leader of MemsONE, summarized the entire
MemsONE project. In this issue, we will introduce themechanical simulator and process analysis tools led by
the Mizuho Information & Research Institute.
As shown in Fig. 1, the mechanical simulator andprocess analysis tools are provided in the MemsONE
system as basic analytical functions that can be usedthrough a software framework in the form of a GUI and
can be linked with the material and process database,for example. The software framework for theMemsONE system comes with CAD and visualization
functions so that coherent mechanical analysis andprocess analysis can be performed through this system
alone.

• Anisotropic wet etching
Provides a simulator to analyze anisotropic wet
etching processes in order to predict transientchanges in the 3D etching profile• Dry etching
Can confirm the etching shape produced through a
dry etching process• Thin film deposition
Creates a 3D structure by emulating a physical orchemical vapor process according to a geometricmethodThe mechanical simulator is a set of programs forstudying and evaluating the mechanical properties of
MEMS devices and can be used in specification studies
during the initial design stage. The simulator may also
be used for final performance evaluations once theshape of the device has been determined. The
mechanical simulator includes the following functions.

• Multiprocessing
Provides a function for creating 3D structures
according to an emulator using a geometric method,and enables the thermal history and other data
described in the 3D structural data and the process
recipe to be used in the mechanical simulator• Stress-strain analysis
Can predict structural behavior, such as vibrations,deformation, and stress characteristics• Electromagnetic field analysis
Can evaluate Lorentz force and distributions ofelectric potential, electric current, and magnetic
fields in devices employing electromagnetic drive
systems

It is our hope that many people engaged in thedesign and development of MEMS devices will makeuse of these tools, and that the tools will contribute to
the development of MEMS industry in Japan.

• Piezoelectric analysis
Can predict structural behavior in devices having
piezoelectric material
Framework• Thermal analysis
Can analyze changes in the temperature distribution
in structures over time and thermal deformation insuch changes

Development of a user-friendly interface• Effect analysis of ambient gases
Can find the damping rate of a MEMS structures thatoscillates rapidly in gases

Mechanicalsimulator

Process
analysis tools

Stress-strain analysis

Anisotropic wet
etching

Electromagnetic analysis
Piezoelectric analysis• Coupling analysis
Can perform coupled analysis of the aforementionedfunctions in the mechanical simulator and cancomprehensively verify and evaluate structuralstress-strain, electrostatic fields, magnetic fields,piezoelectric and other drive mechanisms, andmoving mechanisms in such MEMS aselectromagnetic actuators, electrostatic actuators,
and thermal actuators

Dry etching

Thermalanalysis

Thin film deposition

Effect analysisof ambient gases

Multiprocessing

Coupled analysis

Expandedfunctions

Knowledge
database

Material andprocess
database

Development of functional modules

Plug-in module

Plug-in database

Fig. 1 Configuration of the MemsONE system

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