利用複合式干涉儀技術之表面3D形貌顯微鏡

Surface Profiler with the Technique of Composite Interferometer

許怡仁(I-Jen Hsu) ； 張群偉(Chun-Wei Chang) ； 林鈺凱(Yu-Kai Lin) ； 侯帝光(Max T. Hou)

《科儀新知》 204期 (2015/09) Pp. 24-34

摘要

本研究團隊於近年來發展並驗證一用以量測表面形貌、且具備奈米準確度的低成本光學系統。該系統是由邁克爾遜干涉儀和馬赫-策德爾干涉儀所組成的複合式干涉儀。利用系統中的相位補償機制，來自光學系統的不穩定和環境干擾所造成的相位偏差可同時獲得補償。在無需特殊屏蔽和保護、以及樣品的特殊製備之下，該系統可進行數毫米尺度的大範圍造影，以及±5 nm以內軸向解析度的量測。此外，以光纖元件為基礎的複合式干涉儀亦可實現具備奈米尺度靈敏度的表面形貌量測，量測的靈敏度與造影的速度亦顯著提升，使該系統可作為一高速、高解析度的大範圍動態造影系統。該系統的軸向精確度經驗證可達到0.82 nm。此系統亦以每幀影像75秒的速度針對洋蔥細胞脫水過程進行高解析度縮時動態造影。目前本研究團隊已利用此技術完成一表面3D形貌顯微鏡的開發，在進一步改良系統的設計之後，此系統不但可同時作高解析度的材料表面光訊號強度與相位分布的量測，且無論是系統的穩定性或靈敏度更均獲得大幅度的提升。

並列摘要

Our research team developed and demonstrated a low-cost optical system for surface profilometry with nanometer-accuracy recently. The system is based on a composite interferometer consisting of a Michelson interferometer and a Mach-Zehnder interferometer. With the phase compensating mechanism, the phase deviation due to the instability of the optical system and environmental perturbation can be compensated simultaneously. The system can perform a large-range imaging in the millimeter scale and a measurement with the axial resolution within 5 nm without special shielding and protection of the system as well as any special preparation of the sample. Furthermore, a fiber-based composite interferometer can also perform the measurement of surface profile with sensitivity at nanometer scale. The measurement sensitivity and imaging speed can be significantly improved such that the system can be used as a high-speed, high-resolution and wide-range dynamical imaging system. The axial precision of the system was examined to be 0.82 nm. High-resolution time-lapsed dynamical imaging of onion cells during dehydration processes were performed with this system with one frame captured in 75 seconds. Our research team has currently completed the development of a surface profiler with this technique. Due to the improvement of the design of the system, it can perform high-resolution measurements of intensity and phase distribution of light signal from surface of material simultaneously. Furthermore, the stability and sensitivity of the system were significantly improved.