An Electrohydrodynamic Micropump for On-Chip Fluid Pumping on a Flexible Parylene Substrate Reporter: sang-chung yang Advisor: Prof. C.H. Liu Chia-Ling Chen1,*, Student Member, IEEE, Selvapraba Selvarasah1, Shih- Hsien Chao1, Azadeh Khanicheh2, Constantinos Mavroidis2, and Mehmet R. Dokmeci1, Member, IEEE 1 ECE Department, NSF-NSEC Center for High Rate Nanomanufacturing, Northeastern University, Boston, MA, USA 2 Mechanical and Industrial Engineering Department, Northeastern University, Boston, MA, USA NEMS2007 Page:242

Sang-chung MSCL Introduction Theory Fabrication Test results Conclusions Outline

Sang-chung MSCL Introduction Micro pump: mechanical :1.moving parts(check-valve membrane) 2.high pumping rate 3.high power consumption 4.fabrication process complicated non-mechanical :1.no moving parts 2.low pumping rate 3.fabricate easily Fig. Piezoelectric pump Fig.EHD micropump

Sang-chung MSCL Parylene NParylene CParylene D 化學結構多一個氯原子多二個氯原子 溫度穩定度可承受較高溫度 透濕性較低的透溼性 沉積速率較慢最快居中 介電常數最強 Ref:XBH Coporation 1.Lightweight 2.Transparent 3.stress-free 4.Biocompatible 5.Compatible with ic fabrication Introduction Fig. parylene-N,C,D

Sang-chung MSCL Theory F: 單位體積所受的力 (force density) E: 電場強度 (electrical density) q: 電荷密度 (charge density) P: 極化向量 (polarization vector) ε: 介電常數 (permittivity of the fluid) ρ: 流體密度 (fluid density) Dominate term inletoutlet Fig. EHD pump

Sang-chung MSCL Fig. A 3D schematic of the flexible EHD micropump Factors that influence the pumping efficiency 1.type of liquid 2.design of the electrodes Size: 5mm*7mm*80μm 20μm Theory

Sang-chung MSCL Fabrication Fig. Fabrication process for EHD micropump on a flexible Parylene-C substrate 1.Parylene-C(10μm ) 2.Au(150nm) 3.SU-8(80μm) Silicon Substrate Parylene-C Spin PR Metal

Sang-chung MSCL Fig. Optical photograph of the micropumps with SU8 1.Thicknesses of more than 5 μm are easy to peel 2.Before depositing parylene need to use adhesion promoters HMDS Fabrication

Sang-chung MSCL Fabrication Silicon substrate Inlet outlet Fig. EHD micropump

Sang-chung MSCL Fig. Optical photograph of pumping pressure set-up Fig. Measured pumping pressure versus electric IPA:Flow velociy about 190 mm/min at applied voltage of 30 volts Dielectric constant=18.6 Viscosity=2.43mP. as Testing Results 5cm

Sang-chung MSCL Conclusions 1.First EHD micropump on a flexible(10μm)Parylene-C substrate 2.Parylene-C substrates are mechanically strong and IC compatible 3.No moving parts 4.For biomedical applications

Sang-chung MSCL CHIP DEMO Ref: agnitio Coporation