Middle-East Journal of Scientific Research 19 (4): 538-543, 2014
ISSN 1990-9233
© IDOSI Publications, 2014
DOI: 10.5829/idosi.mejsr.2014.19.4.13580
Corresponding Author: Roer Eka Pawinanto, Institute of Microengineering and Nanoelectronic (IMEN),
Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia.
538
Design Consideration of Planar Embedded Micro-Coils for
Electromagnetic Actuator of Fluids Injection System
Roer Eka Pawinanto, Jumril Yunas, Muzalifah Mohd. Said,
Burhanudin Yeop Majlis and Azrul Azlan Hamzah
Institute of Microengineering and Nanoelectronic (IMEN),
Universiti Kebangsaan Malaysia, Bangi 43600, Malaysia
Abstract: In this work, the design and optimization of electromagnetic micro-actuator induced by an embedded
planar micro-coil is discussed. The actuator design is optimized to enable significant increase of the actuation
force and magnetic flux density at low power consumption. Therefore, this work is focused on theoretical
analysis of magnetically actuated membrane which has been induced by a planar embedded micro-coil. The
design and geometry of the planar micro-coil are discussed in detail in this report. Furthermore, the parameters
of coil dimension such as width, space and number of turn, were varied and compared by implementing 3
different permanent magnet materials (Neodymium, SmCo and AlNiCo) to obtain optimum force. As the results,
the geometry of the micro-coil and the permanent magnet material greatly affect to the magnetic flux density and
are highly related to the generated force. This work is greatly benefit for microfluidic injection system integrated
in Lab-on-Chip.
Key words: Micro-coil Electromagnetic actuator Finite element analysis MEMS
INTRODUCTION order to achieve optimum magnetic force and magnetic
Recently, micro-actuators for liquid injection system for the fluid sample injection with a maximum flow rate of
that driven by electromagnetic field have gotten a lot of 10 nL/hr at electrical power consumption of lower than 100
attention on many fields due to their compact structure, mW.
high actuation force at very low power consumption and In its application, the actuators play important factor
easy fabrication as well as ability for integration [1-3]. on the performances of the injection system. As reported
Planar micro-coil is widely used because it has several by [2, 10], the actuation of a membrane is affected by the
advantages such as thin structure, low volume and the coil geometry. Unfortunately, there were no optimized
possibility to integrate directly into the actuator system results yet that ensure the capability of the coil
[4-5]. performance. Therefore, this work is focused on the
Various types microactuators that was applied for theoretical analysis of magnetically actuated membrane
fluids injection system have been reported in some induced by a planar embedded microcoil. The parameters
literature. The common actuator system consist of of coil geometry, materials and structure are intensively
magnetic, magneto hydrodynamic, thermal, electostatic investigated in this study.
and piezoelectric based actuator pump [6-9]. In order to
obtain a low flow rate, it is necessary to have a controlled Actuator Design: Figure 1 shows the schematic
low actuator force withsufficient low deflection of the structure of the microactuator used as fluids injector. The
membrane. Therefore, an optimized embedded planar system consist of permanent magnets, polyimide
micro-coil for the magnetically membrane actuation membrane with embedded microcoil and the silicon
purpose is reported. The actuator design is optimized in chamber.
flux density which is useful to actuated a thin membrane