微懸臂梁感測器之力學模型與最佳化設計

Abstract

本文建立一個簡單的力學模型，連結分子間作用力與微懸臂梁感測器表面作用力的關係，並由修正的Stoney方程式與材料力學的方法推導微懸臂梁撓曲與表面作用力的關係。基於此模型作適當假設，由數值模擬微懸臂梁之撓曲與時間關係，模擬結果與文獻實驗數據趨勢符合，確立微懸臂梁感測器的外力作用機制，並完成程序化的分析模式。此外，壓阻式微懸臂梁感測器不須經由光學量測，適用於微小化，為了提高壓阻靈敏度，藉由此模型作有限元素法分析，模擬在微懸臂梁上鑿不同形狀的洞，找出最佳的壓阻式微懸臂梁設計。

A simple mechanical model is set up to relate the intermolecular forces and the surface resultant forces and the tip deflection of the micro-cantilever beam. A computer simulation including a random docking process is performed to develop simulating the relationship between the tip deflection and docking time. Comparing with experimental data, the tendency is consistent. Besides, due to the convenience of the piezo-resistive cantilever sensors without resorting to laser detection, a finite element analysis is made for the better design of the piezo-resistive cantilever sensors with different shape of holes, which can heighten the sensitivity of detection.