An Innovative Mechanism to Amplify Testing Force Resolution of Silicon Dioxide Micro Cantilevers

測試二氧化矽微懸臂樑之新型力量放大機構

劉顯光(Hsien-Kuang Liu) ； 王淵民(Yuan-Ming Wang) ； 廖為忠(Wei-Chong Liao)

《中國機械工程學刊》 39卷2期 (2018/04) Pp. 197-205

摘要

A micro cantilever is usually adopted as micro structure for sensors; therefore, the micromechanical testing of the cantilever becomes an important issue. However, due to requirement of intensive devices incorporated in compact 3C products, MEMS devices are likely to evolve as NEMS devices. Some nano scale NEMS devices may need to work with stroke in the range of micro scale. Therefore, to develop a simple testing methodology for NEMS devices that can amplify either force or stroke is important. An innovative double lever mechanism is proposed to mount on the micro force testing machine in order to increase force measurement resolution for silicon dioxide micro cantilevers with film thickness only 1μm, and achieve their valid strength and Young modulus data. Design of this double lever mechanism is based on the law of the lever using an asymmetrical lever. Two sets of asymmetrical levers with four pivot joints are combined, and bearings as well as various lubricants are applied at joints in order to minimize friction and evaluate force amplification ratio. Three kinds of lubricants with different viscosities at the bearings are found to better increase the accuracy of the mechanism than the counterpart without lubricant.

關鍵字

amplify ； micromechanical testing ； doublelever mechanism ； force resolution ； lubricant

並列摘要

微懸臂樑經常作為微感測器，因此微懸臂樑的機械性質測試成為微機電系統重要議題，甚至需要延伸到奈米機電系統。有些奈米機電系統尺度很小，卻需要具有微米的行程，所以開發新型簡單測試方法，又能放大測試力量或行程非常重要。本論文提出一種新型雙槓桿力量放大機構，可以與微拉力試驗機結合，能維持較大行程，並能針對厚度僅有1 微米的二氧化矽薄膜微懸臂樑，測試出正確的彎曲強度及楊氏模數。機構的設計串聯兩套非等臂槓桿機構，其關節處必須適當潤滑，使機構具備最大的力量放大倍數。