SI MICRO PROBE AND SIO2 MICRO TUBE ARRAY INTEGRATED WITH NMOSFETS

Kuniharu Takei, Takahiro Kawashima, Hidekuni Takao, Kazuaki Sawada, and Makoto Ishida Transducers’07

Presenter：Wen-Fan Liao

ID： g946220

Instructor： Cheng-Hsien Liu

Outline

Introduction Process Results Conclusion References

Introduction

Neural activity recording is important to analyze neural networks

Recording site and invasiveness are issues Proposed micro probes and tube array for neural p

enetrating devices fabricated by Vapor-Liquid-Solid (VLS) method

Process

Process sequence of probe, tube with on-chip MOSFETs

Process

SEM images of Si micro probe before and after deposition of SiO2 by PECVD; (a) Before deposition, (b) After deposition

Process

Fabricated Si micro probe and SiO2 micro tube array with on-chip MOSFETs

Diameter and length for Si microprobe are 2μm and 30μm respectively. SiO2 tube is 2.7μm in inner diameter, 3.6μm in outer diameter, and 29μm in length

Results

SiO2 thickness by PECVD as a function of deposition time

Results

Microscope images of maximum bending the probe and tube before breaking

Probe diameter : 3μmTube diameter : 4μmMaximum displacements of Si micro probe and SiO2 micro tube are 3.75μm and 3.25μm respectively

Results

FEM simulation results: (1) shows the available added pressure as a fuction of displacement, (b) indicates the maximum stress as a function of added pressure

1.95MPa

2.05MPa

3.0GPa

3.2GPa

Results

Estimated capable penetration pressure at the maximum stress for the micro probe and tube

1750MPa

400MPa

Results

Photographs and schematic images for which probes and tubes were penetrated (1,2) and extracted (3) from the gelatin

Conclusion

This work reports the development of Si micro probe and SiO2 micro tube array with on-chip MOSFETs for a neural recording device

This device is expected to be suitable for analysis of neural behavior with low invasiveness, which can be applied in neuron science or other applications

References Kuniharu Takei, Takahiro Kawashima, Hidekuni Takao, Kazuaki Sawa

da, and Makoto Ishida, “SI MICRO PROBE AND SIO2 MICRO TUBE ARRAY INTEGRATED WITH NMOSFETS,” Transducers’07, Lyon, France, June 2007

Kuniharu Takei, Takahiro Kawashima, Kazuaki Sawada, and Makoto Ishida, “MECHANICAL PROPERTIES OF MICRO PROBE AND TUBE ARRAY FOR NEURAL PENETRATING DEVICES,” Engineering in Medicine and Biology Society, 2007. EMBS 2007. 29th Annual International Conference of the IEEE

http://www.mems.nthu.edu.tw/nano/071228_MEMS neuroscience.ppt

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