Measurement of highly reflective surface shape using wavelength tuning Fizeau interferometer and polynomial window function
Measurement of highly reflective surface shape using wavelength tuning Fizeau interferometer and polynomial window function
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DOI:
10.1016/j.precisioneng.2016.02.011
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发表时间:
2016-07
影响因子:
3.6
通讯作者:
Yangjin Kim;N. Sugita;M. Mitsuishi
中科院分区:
文献类型:
--
作者:
Yangjin Kim;N. Sugita;M. Mitsuishi
In this study, a 5N− 4 phase shifting algorithm comprising a polynomial window function and a discrete Fourier transform is developed to measure interferometrically the surface shape of a silicon wafer, with suppression of the coupling errors between the higher harmonics and the phase shift error. A new polynomial window function is derived on the basis of the characteristic polynomial theory by locating five multiple roots on the characteristic diagram. The characteristics of the 5N− 4 algorithm are estimated with respect to the Fourier representation in the frequency domain. The phase error of the measurements performed using the 5N− 4 algorithm is discussed and compared with those of measurements obtained using other conventional phase shifting algorithms. Finally, the surface shape of a 4-in. silicon wafer is measured using the 5N− 4 algorithm and a wavelength tuning Fizeau interferometer. The accuracy of the measurement is discussed by comparing the amplitudes of the crosstalk noise calculated by other algorithms. The uncertainty of the entire measurement was 34 nm, better than that of any other conventional phase shifting algorithms.