Sensors and Actuators B Chemical

Sensors and Actuators B 140(2009)342–348

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Sensors and Actuators B:

Chemical

j o u r n a l h o m e p a g e :w w w.e l s e v i e r.c o m /l o c a t e /s n

b

Characterization of a multi-chip microelectrofluidic bench for modular fluidic and electric interconnections

Sunghwan Chang 1,Sang Do Suk,Young-Ho Cho ∗

Digital Nanolocomotion Center,Korea Advanced Institute of Science and Technology,373-1Guseong-dong,Yuseong-gu,Daejeon 305-701,Republic of Korea

a r t i c l e i n f o Article history:

Received 1November 2006

Received in revised form 11January 2009Accepted 16January 2009Available online 28May 2009Keywords:

Microelectrofluidic bench Multi-chip system

Microelectrofluidic modules Electrofluidic interconnection

Low-pressure-loss interconnection Low-temperature interconnection

a b s t r a c t

We present the design,fabrication,and characterization of a multi-chip microelectrofluidic bench,achiev-ing both fluidic and electric interconnections with simple and low pressure-loss interconnections.The microelectrofluidic bench provides easy alignment of fluidic interconnection using microfabricated annu-lar fluidic connectors;also provides simple electric interconnection using isotropic conductive adhesives at room temperature.Thus,the present microelectrofluidic bench provides a modular concept for fluidic and electric interconnection.In experimental study,we characterize pressure losses,electric resistances loss,and pressure stability of the interconnection.The average pressure drop per each fluidic contact is measured 0.12±0.19kPa at the DI water flow rate from 10to 100␮l min −1.The electric resistance per each electric contact is measured as 0.64±0.29 .The fluidic interconnection endures maximum pressure of 115±11kPa.The present microelectrofluidic bench,therefore,offers a simple and low pressure-loss electrofluidic modular interconnection for electrofluidic multi-chip microsystems.

©2009Published by Elsevier B.V.

1.Introduction

A significant amount of research has been devoted to the development of microfluidics and MEMS (Microelectromechanical Systems)over the past pared with numerous func-tional microelectrofluidic devices [1],few approaches on interfaces and interconnections [2–5]among devices have been reported for integration of microsystems.Interconnection method is often ignored in research environments such as academic laboratories,because skilled personnel operate systems.However,it must be addressed prior to commercial success of any microfluidic appli-cations where manual manipulation is not economical and the macro-to-micro interface must be developed [6].

Recent microfluidic systems require multi-physical interfaces including not only fluidic interconnection but also electric inter-connection.However,most of previous interconnection methods in microfluidics focus on fluidic interconnections [2–4].Previous interconnection methods for multi-chip systems have included flu-idic interconnection:anodic bonding [2],o-ring tubing [3],and mechanical interlocking [4].In these methods,high temperature [2]of 400◦C,relatively big waste volume [3]of 30␮l,and hard alignment of interconnected devices [4]become a bottleneck of

∗Corresponding author.Tel.:+82423508691;fax:+82423508690.E-mail address:nanosys@kaist.ac.kr (Y.-H.Cho).

1Current Address:Nano-Mechanical Systems Research Division,Korea Institute of Machinery &Materials (KIMM),Republic of Korea.

simple interconnection.Additionally,thermofluidic or biochemi-cal multi-chip microsystems of nowadays require also electrical interconnections.Recently,Yang and Maeda have suggested socket-type electric interconnections [6]with fluidic interconnections;however,they used silicon tubes for fluidic interconnections,so more wastes of sample fluids occurred in fluidic interconnections than previous work [2–4]which has wastes of samples about 5–30␮l.

Compared to integrated single-chip microsystems,intercon-nected multi-chip systems [7],composed of several chips,have problems of assembly and interconnection,while permitting a vari-ety of materials and process alternatives.Therefore,we propose a microelectrofluidic bench to achieve simple,low pressure-loss,low-temperature electrofluidic interconnection for interconnected multi-chip systems.The microelectrofluidic bench provides easy alignment of fluidic interconnections using microfabricated annu-lar fluidic connectors;also provides simple electric interconnection using isotropic conductive adhesives (ICA)[8]at room tempera-ture.Thus,compared to previous interconnection methods [2–6],the present microelectrofluidic bench can provide easier fluidic and electric interconnections as a modular concept.2.Design and fabrication

2.1.Design

Fig.1shows a perspective view of a prototype bench for a four-device interconnection,which offers two pairs of fluidic I/O

0925-4005/$–see front matter ©2009Published by Elsevier B.V.doi:10.1016/j.snb.2009.01.075