Guo Tong, Guo Xinyuan, Wei Yangyang
Opt Express. 2021 Oct 25;29(22):36689-36703. doi: 10.1364/OE.443093.
Optical interferometers are widely used in the measurement of micro- and nanoscale surface topography. However, their accuracy and resolution can be seriously affected by environmental noise. We present a multi-mode interferometric measurement system based on wavelength modulation and active vibration resistance. This supports two measurement modes: wavelength-scanning interferometry, which is suitable for structured surfaces, and wavelength-tuning interferometry, which is suitable for smooth continuous surfaces. In addition, the system can measure the optical path difference of the current position in real time, which is convenient for making system adjustments and improving the measurement accuracy. The proposed system was used to measure 1.806 µm and 43.2 nm step height standards. Under different degrees of vibration, the measured heights in the two modes agreed well with the calibrated values.
光学干涉仪广泛应用于微米和纳米尺度表面形貌的测量。然而，其精度和分辨率会受到环境噪声的严重影响。我们提出了一种基于波长调制和主动抗振的多模式干涉测量系统。该系统支持两种测量模式：适用于结构化表面的波长扫描干涉测量法，以及适用于光滑连续表面的波长调谐干涉测量法。此外，该系统能够实时测量当前位置的光程差，便于进行系统调整并提高测量精度。所提出的系统用于测量1.806 µm和43.2 nm的台阶高度标准。在不同程度的振动下，两种模式下测得的高度与校准值吻合良好。
