可應用於CMOS電磁閥門晶片之永磁薄膜電鑄技術研究

A study on electroforming techniques for permanent magnet thin films applied to CMOS electromagnetic valve devices

黃彥筌(Yen-Cyuan Huang黃彥筌)

指導教授 ： 呂志誠

國立臺北科技大學/機電學院/機電整合研究所/碩士(2010年)

摘要

為了實現CMOS-MEMS電磁閥門，最關鍵之技術為製程加工溫度與永磁材料硬磁特性的選擇及利用各種微加工方法將硬磁材料沉積在微結構上，本研究先以黃銅片為基材電鑄硬磁材料鈷鎳錳磷合金並探討電鑄時外加磁場下的磁性質，再將鈷鎳錳磷合金電鑄在CMOS-MEMS標準製程所設計的電磁閥門晶片上，並提出兩種可行方法，其一為利用化學浸鍍鋅(zincating)將晶片上鋁膜置換成鋅，隨後電鑄銅當種子層(seed layer)；另一可行之方法為利用電子束蒸鍍20 nm鈦與200 nm銅當種子層，待電鑄硬磁材料完成後，再進行剝離(lift off)製程，以上兩種製程方法可成功將硬磁材料電鑄在晶片所設計的閥門結構上，晶片面積大小為1.4×1.3 mm2，閥門電鑄面積為0.32 mm2，利用鋅置換後電鑄鈷鎳錳磷硬磁材料經測量磁性質可得，矯頑磁力(coercivity, Hc) 為469 Oe，剩餘磁化強度(remanent magnetization, Mr)為0.14 T，最大磁能積(maximum magnetic product, BHmax )為0.19 MGOe，這些成功的結果可望應用於未來生物感測晶片微流體控制之CMOS-MEMS電磁閥門。

關鍵字

微電鑄 ； 鈷鎳錳磷合金 ； 硬磁材料 ； CMOS-MEMS電磁閥門

並列摘要

In order to achieve CMOS-MEMS electromagnetic valves, the most critical coating techniques are determination of processing temperature, hard magnetic properties of permanent magnetic materials and micro-fabrication methods so that one can deposit hard magnetic material on designate microstructures. In this study, brass substrates are used to electroform CoNiMnP hard magnetic alloy with external magnetic fields, and the as-deposited magnetic properties are then discussed. Next, two feasible pre-process methods are proposed to carry out micro-electroforming process on CMOS-MEMS electromagnetic valve chips. One is the chemical zincating method to replace aluminum on the chip by zinc and copper to form a seed layer. The other process is deposition of 20 nm thick of titanium and 200 nm thick of copper using electron-beam evaporation to form a seed layer for further micro-electroforming. After the micro-electroforming step, a lift off process is proceeded to define the pattern of hard magnetic material. These processes can successfully electroform hard magnetic materials on the specific area of the chip. The CMOS-MEMS chip size is 1.4 mm × 1.3 mm, and micro-electroforming valve area is 0.32 mm2. By applying the chemical zincating method, the deposited magnetic properties of CoNiMnP hard magnetic material can be measured a coercivity of 469 Oe, remanent magnetization of 0.14 T, the maximum energy product (BHmax) of 0.19 MGOe. These successful results are promising for the future applications of CMOS-MEMS electromagnetic valve devices embedded in micro-fluidic control elements of a biosensor chip.

並列關鍵字

Microelectroforming ； CoNiMnP alloy ； Permanent magnet ； CMOS-MEMS electromagnetic valves

參考文獻

[29] 陳彥志，結合酵素場效電晶體與微閥門之葡萄糖感測技術，碩士論文，國立台北科技大學機電整合所，台北，2009。

[1] Minhang Bao, Weiyuan Wang, “Future of micro electromechanical systems

[3] Hyoung J. Cho and Chong H. Ahn, ”A Bidirectional Magnetic Microactuator Μsing Electroplated Permanent Magnet Arrays,” J. Micromech. Microeng., vol. 11, no. 1, 2002, pp. 78-84.

[5] Jemmy Sutanto, Peter J Hesketh and Yves H Berthelot, ”Design, microfabrication and testing of a CMOS compatible bistable electromagnetic microvalve with latching/unlatching mechanism on a single wafer,” J. Micromech. Microeng., vol. 16, no. 2, 2006, pp. 266–275.

Valles, E. Gomez, ”Design, fabrication and characterization of an externally