磁域建構之無線圈電磁式奈/微米機電系統在細胞操縱術之應用

Abstract

本計畫中，我們應用MEMS/NEMS製程在矽晶圓上設計製作三種具有特殊幾何排列之奈米磁電結構陣列(主要組成:具有壓電性質之鋯鈦酸鉛薄膜與具有磁致伸縮性質之鎳奈米結構陣列)，對這些陣列中的鎳奈米結構以”在晶片上(On-Chip)”方式施加一電場並藉由逆磁電效應(Converse Magnetoelectric Effect)則可使鎳奈米結構內部產生一電場導引之磁域轉變(即對鋯鈦酸鉛薄膜施加電場，藉由壓電效應在薄膜內產生應變，此應變會因鋯鈦酸鉛薄膜與鎳奈米結構之間的機械耦合而傳遞至鎳奈米結構，再藉由磁致伸縮效應，此應變會使鎳奈米結構內部之單一磁域產生改變)。進一步以電場依序控制陣列中每一個鎳奈米結構之磁域變化，透過這些有序變化之磁域陣列即可牽引 磁珠，使磁珠在磁域陣列上前進。透過三種不同奈米磁電結構陣列設計並結合以電場 依序 控制 陣列中 之磁域 方式，則 能使磁珠在晶片上分別進行直線運動，蜿蜒曲線運動，以及圓周運動。若埋置磁珠於細胞內，則能成功達成以On-Chip電場控制磁域方式來操縱含有磁珠之細胞在晶片上進行各式運動之目的。本計畫的預期研究結果將成為未來以奈/微米電磁式細胞操縱術建構之可攜式System-On-Chip生醫系統晶片發展之重要關鍵技術。

In this proposal, we propose our new approach, i.e., magnetic-domain-configured coil-less electromagnetic MEMS/NEMS, for cell-manipulation applications. These MEMS/NEMS systems consisting magnetoelectric patterned nanostructures (i.e., single-domain Ni-nanobar arrays on the top of a patterned piezoelectric PZT thin film deposited on a silicon wafer) are used to demonstrate an on-chip electrical control of the magnetic single-domain in the Ni-nanobar due to the converse magnetoelectric effect. That is, when an electric field is applied to the PZT film, in-plane strains are developed in the film through the piezoelectric effect. Subsequently, the strains are transmitted to the Ni-nanobars due to mechanical coupling between the PZT-film and Ni-nanobars. Finally, the strains transform the single-domain of each Ni-nanobar due to the magnetostriction. This achieves an electric-field-induced magnetic single-domain transformation in the Ni-nanobar. Furthermore, through a consequent electrical-control of magnetic single-domain transformation in a geometric-arranged single-domain Ni-nanobar array, the nanoscale magnetic bead can be moved between neighboring magnetic domains in the array. By utilizing three different geometric-arranged Ni-nanobar arrays, we can demonstrate the magnetic beads can be manipulated in a line, zigzag, and circle movements on the arrays. If the magnetic beads are embedded into a cell, the cell can be manipulated in the same movements. This achieves an on-chip coil-less electromagnetic actuating for cell manipulations. These expected experiment results in our proposal would be critical advancements for future electromagnetic MEMS/NEMS in cell-manipulation applications.