本論文展示利用微機電技術，發展能強化電子顯微鏡影像對比之靜電式相位板，以拍攝未經染色之高分辨生物樣品影像。在傳統穿透式電子顯微鏡中，對生物試片進行拍攝，由於樣品通常為碳、氫、氧等與電子作用小的輕元素構成，需經過重金屬染色步驟，以增強影像上的吸收對比強度。但染劑與重金屬元素具有生物毒性，染色固定後細胞死亡且改變原有型態。根據Zernike的相位對比增強理論，應用Boersch提出的靜電式相位板概念，可於電子顯微鏡之後聚焦面改變穿透光與繞射光的相位差，即時增強影像的相位對比，無須對試片事先進行前處理，實現相位對比電子顯微鏡。本論文中，描述以微機電技術實現Boersch靜電式相位板的方法，提出改良型相位板晶片，具有自我檢測與局部加熱排除汙染的功能。相位板主體為三層金屬與兩層絕緣層構成的環形結構，以一根懸臂支撐橫跨在光圈上，對中間金屬電極進行偏壓，可調整通過環內的電子束相位，當相位差達到90度，將提升影像低頻區之相位對比。本計畫已初步獲得生物樣本之相位對比增強影像。在設計上透過加大光圈尺寸與縮小懸臂線寬，可減少相位板引發的背景吸收效應。絕緣層造成的電荷累積，會產生額外電場干擾成像，使用特殊的絕緣層內縮技術，可大為降低此效應對繞射圖形的扭曲。

This research purposes the development of phase contrast electron microscopy by a MEMS electrostatic phase plate, and the achievement to high resolution bio-sample imaging without staining. TEM provides high resolution images to in-organic materials due to high contrast of the in-organic materials to the supporting substrate materials when interacted with electron beams. In bio-image, most of the bio-specimen, containing mostly carbohydrate, needs staining to enhance the image contrast, due to the weak interactions between low Z atoms and incident electron beam. Zernike invented a phase plate to converse the phase information of transparent object to image intensity for getting high contrast images in optical microscopy. To obtain nm resolution for bio-molecule observation, Matsumoto proposed the employment of Boersch micro-lens (Electrostatic Zernike Phase Plate, EZPP) to shift the phase of a center electron beam to improve TEM phase images. The highest contrast occurs at the EZPP providing π/2 phase shift. We demonstrate an advanced version of the EZPP for protein visualization after the reduction of electron beam interaction. Lower the background absorption contrast by increasing the demension of the aperture and decreasing the width of the supporting cantilever. A special retraction design could avoid the electron charging to distort the diffraction pattern.

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