With the development of electronic technology in recent years, electronic components become increasingly miniaturized. At the same time a more accurate measurement method becomes indispensable. In the current measurement of nano-level, the Michelson interferometer with the laser diode is widely used, the method can measure the object accurately without touching the object. However it can't measure the step height that is larger than the half-wavelength. In this study, we improve the conventional Michelson interferometer by using a super luminescent diode and continuous wavelet transform, which can detect the time that maximizes the amplitude of the interference signal. We can accurately measure the surface-position of the object with this time. The method used in this experiment measured the step height of 20 microns.

Date Published: 19 December 2013
PDF: 7 pages
Proc. SPIE 9046, 2013 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Systems, 90461I (19 December 2013); doi: 10.1117/12.2042640

Published in SPIE Proceedings Vol. 9046:
2013 International Conference on Optical Instruments and Technology: Optoelectronic Measurement Technology and Systems
Hwa-Yaw Tam; Kexin Xu; Hai Xiao; Jigui Zhu, Editor(s)