Fabrication of Micro-Force Transducer Based on Carbon Nano-Flake Balls for Assisting Drosophila Monitoring system

1) Department of Power 2) Institute of Informatics, The purpose of this study is to fabricate a micro force sensor for assisting drosophila 's monitoring system. A novel three-dimensional carbon-based material called carbon nano flake ball (CNFB) was used as it exhibits a large surface-area and high electrical conductivity. Moreover, CNFB can be easily fabricated by using a one-step fabrication process via microwave plasma chemical vapor deposition (MPCVD). In present study, CNFB has been successfully grown on Si/SiO
₂
/Al
₂
O
₃
substrate. Two types of pretreatment was done to the substrate, sol-gel catalyst coating and ultrasonic pretreatment in titanium powder suspension. The morphology of CNFB was observed by using scanning electron microscope (SEM). The results show that using sol-gel catalyst coating as pretreatment precursor results in a larger ball-size but lower coverage area of CNFB. Moreover, carbon nanotubes (CNTs) observed as iron particles might diffuse into AL
₂
O
₃
and act as catalyst for growing CNT. By using ultrasonic pretreatment, adjusting the sonication time and concentration of methane, we can achieve a higher coverage area of CNFB. Through HF wet etching, SiO
₂
layer was removed and only Al
₂
O
₃
/ CNFB layer has been left. Then, the force sensing performance was measured through the change in electrical resistivity while A1203 / CNFB layer was applied to force.