Author(s): Zhou, Y (Zhou, Yi); Tang, Y (Tang, Yan); Deng, QY (Deng, Qinyuan); Liu, JB (Liu, Junbo); Wang, J (Wang, Jian); Zhao, LX (Zhao, Lixin)

Source: OPTICS AND LASER TECHNOLOGY  Volume: 93  Pages: 187-193  DOI: 10.1016/j.optlastec.2017.03.005  Published: AUG 1 2017  

Abstract: Dimensional metrology for micro structure plays an important role in addressing quality issues and observing the performance of micro-fabricated products. In white light interferometry, the proposed method is expected to measure three-dimensional topography through modulation depth in spatial frequency domain. A normalized modulation depth is first obtained in the xy plane (image plane) for each CCD image individually. After that, the modulation depth of each pixel is analyzed along the scanning direction (z-axis) to reshape the topography of micro samples. Owing to the characteristics of modulation depth in broadband light interferometry, the method could effectively suppress the negative influences caused by light fluctuations and external irradiance disturbance. Both theory and experiments are elaborated in detail to verify that the modulation depth-based method can greatly level up the stability and sensitivity with satisfied precision in the measurement system. This technique can achieve an improved robustness in a complex measurement environment with the potential to be applied in online topography measurement such as chemistry and medical domains. (C) 2017 Elsevier Ltd. All rights reserved.

IDS Number: ET1OR 

ISSN: 0030-3992 

eISSN: 1879-2545