奈米級探針編碼技術之研究

Research on Nano Probe Encoding

林彥君(Yen-Chun Lin)

指導教授 ： 張所鋐

國立臺灣大學/工學院/機械工程學研究所/碩士(2004年)

https://doi.org/10.6342/NTU.2004.00782

摘要

隨著奈米科技的發展，各種奈米尺度下的理論以及應用研究的腳步不斷地向前邁進；而掃描式探針顯微鏡的誕生，更使得奈米級的表面形貌檢測技術有了更進一步的突破。掃描式探針顯微鏡與各種微、奈米級結構搭配所衍生的應用已成為相當重要的跨領域研究項目。因此若能將已知的成果經由創新性的結合，進而產生突破性的應用，相信對於目前奈米科技的實用化以及未來更深入的研究，都具有承先啟後的助益。
本文的目標為新式探針編碼技術的架構設計與效能驗證。利用掃描式探針顯微鏡的探針高度回饋機制與表面形貌檢測能力，搭配微、奈米等級線寬的週期性結構，完成奈米級探針編碼技術的具體實現與評估。其技術重點在於，當探針與週期性結構之間以特定形式相對運動時，會使探針的檢測訊號產生「脈衝寬度調變」的現象，即對週期性結構的線寬在訊號上進行細分割，使得原本週期為微米或次微米級等級的柵狀結構，在位移測量上的解析度提升至奈米級。為了對此編碼技術進行最佳化的呈現與驗證，首先對探針編碼行為進行數學上的描述，再利用電腦輔助工程軟體MSC.ADAMS進行無因次參數化的設計與動態模擬，尋找與現有掃描式探針顯微鏡機台、材料製程以及相關儀器可互相配合的設計參數，並與實驗所獲得的編碼結果相互驗證。奈米級探針編碼技術架構可做為超高解析度編碼器以及高密度儲存裝置的雛形，未來將具有相當大的發展潛力。

關鍵字

訊號細分割 ； 原子力顯微鏡 ； 位移編碼器 ； 週期性結構 ； 探針編碼技術

並列摘要

With the development of nanotechnology, many kinds of theories and applications in the nano-scale world have been continuously proposed, especially the first demonstration of the scanning probe microscope (SPM) which is capable of imaging surface topography with atomic scale resolution. Multidisciplinary research based on the combination of the SPM and structures fabricated by Micro-Electrical-Mechanical System (MEMS) process is getting more and more popular. Therefore, it will definitely be a milestone on the roadmap of nanotechnology if proposed technologies are creatively organized to open a floor for potential novelty.

In this paper, a novel probe encoding technology is proposed, including the systematic design and the demonstration of its encoding performance. The concept has been successfully realized with an atomic force microscope (AFM) system probing the topography of a grating. For the purpose of encoding, a grating moves under the probe oscillating at a relatively high frequency. When the probe tip contacts with a scale on the grating, the topography signal of the periodic surface is divided into many pulse segments whose pulse widths are much thinner than the original periodicity. This phenomenon, due to the relative motion of the probe and the grating, is the same as the pulse width modulation (PWM) widely used in the class-D power amplifier. With the signal subdivision, the resolution of the grating is greatly improved, from tens of a micrometer to tens of a nanometer. Optimal parameters are obtained by mathematical descriptions and computer-aided dynamic simulations for the following experiments. By the experiments, the performance of the probe encoding technology is analyzed and its availability as a high-resolution displacement encoder is well-proved.

並列關鍵字

probe encoding technology ； displacement encoder ； signal subdivision ； periodic grating ； AFM

參考文獻

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