Measuring the thickness profiles of wafers to subnanometer resolution using Fabry–Perot interferometry

Abstract

The resolution of an angle-scanning technique for measuring transparent optical wafers is analyzed, and it is shown both theoretically and experimentally that subnanometer resolution can be readily achieved. Data are acquired simultaneously over the whole area of the wafer, producing two-dimensional thickness variation maps in as little as 10 s. Repeatabilities of $0.07\mathrm{nm}$ have been demonstrated, and wafers of up to $100\mathrm{mm}$ diameter have been measured, with $1\mathrm{mm}$ or better spatial resolution. A technique for compensating wafer and system aberrations is incorporated and analyzed.

© 2007 Optical Society of America

Sub-nanometer metrology of optical wafers using an angle-scanned Fabry-Perot interferometer

John Arkwright, David Farrant, and Jun Zhang
Opt. Express 14(1) 114-119 (2006)

Development of a wafer warpage measurement technique using Moiré-based method

Hung-Lin Hsieh, Yung-Guang Huang, Yu-Hsuan Tsai, and Yao-Hui Huang
Appl. Opt. 55(16) 4370-4377 (2016)

Modified Roberts-Langenbeck test for measuring thickness and refractive index variation of silicon wafers

Jungjae Park, Lingfeng Chen, Quandou Wang, and Ulf Griesmann
Opt. Express 20(18) 20078-20089 (2012)

Reflectometry-based wavelength scanning interferometry for thickness measurements of very thin wafers

Young-Sik Ghim, Amit Suratkar, and Angela Davies
Opt. Express 18(7) 6522-6529 (2010)

Subnanometer absolute displacement measurement using a frequency comb referenced dual resonance tracking Fabry–Perot interferometer

Minhao Zhu, Haoyun Wei, Shijie Zhao, Xuejian Wu, and Yan Li
Appl. Opt. 54(14) 4594-4601 (2015)