Abstract

We have proposed and demonstrated a novel method that can determine both the geometrical thickness and refractive index of a silicon wafer at the same time using an optical comb. The geometrical thickness and refractive index of a silicon wafer was determined from the optical thickness using phase information obtained in the spectral domain. In a feasibility test, the geometrical thickness and refractive index of a wafer were measured to be 334.85 μm and 3.50, respectively. The measurement uncertainty for the geometrical thickness was evaluated as 0.95 μm (k = 1) using a preliminary setup.

© 2010 OSA

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    [CrossRef]
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2009 (3)

2007 (2)

2006 (1)

2005 (1)

D. Schurz, W. W. Flack, and R. L. Hsieh, “Dual side lithography measurement, precision and accuracy,” Proc. SPIE 5752, 97–105 (2005).

2004 (1)

M. J. Jansen, H. Haitjema, and P. H. J. Schellekens, “A scanning wafer thickness and flatness interferometer,” Proc. SPIE 5856, 334–343 (2004).
[CrossRef]

2003 (1)

2000 (1)

1998 (1)

1997 (1)

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

1989 (1)

Arkwright, J. W.

Brar, B.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Choi, J.

G. Nam, C.-S. Kang, H.-Y. So, and J. Choi, “An uncertainty evaluation for multiple measurements by GUM, III: using a correlation coefficient,” Accredit. Qual. Assur. 14(1), 43–47 (2009).
[CrossRef]

Dobson, C. C.

Fairman, P. S.

Farrant, D. I.

Feldman, L. C.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Flack, W. W.

D. Schurz, W. W. Flack, and R. L. Hsieh, “Dual side lithography measurement, precision and accuracy,” Proc. SPIE 5752, 97–105 (2005).

Flavin, D. A.

Ghim, Y.-S.

Haitjema, H.

M. J. Jansen, H. Haitjema, and P. H. J. Schellekens, “A scanning wafer thickness and flatness interferometer,” Proc. SPIE 5856, 334–343 (2004).
[CrossRef]

Haruna, M.

Hashimoto, M.

Hirai, A.

Hori, Y.

Hsieh, R. L.

D. Schurz, W. W. Flack, and R. L. Hsieh, “Dual side lithography measurement, precision and accuracy,” Proc. SPIE 5752, 97–105 (2005).

Jansen, M. J.

M. J. Jansen, H. Haitjema, and P. H. J. Schellekens, “A scanning wafer thickness and flatness interferometer,” Proc. SPIE 5856, 334–343 (2004).
[CrossRef]

Joo, K.-N.

Kang, C.-S.

G. Nam, C.-S. Kang, H.-Y. So, and J. Choi, “An uncertainty evaluation for multiple measurements by GUM, III: using a correlation coefficient,” Accredit. Qual. Assur. 14(1), 43–47 (2009).
[CrossRef]

Kim, S.-W.

Lu, Z. H.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Maruyama, H.

Matsumoto, H.

McCaffrey, J. P.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Minoshima, K.

Mitsuyama, T.

Murphy, D. F.

Nam, G.

G. Nam, C.-S. Kang, H.-Y. So, and J. Choi, “An uncertainty evaluation for multiple measurements by GUM, III: using a correlation coefficient,” Accredit. Qual. Assur. 14(1), 43–47 (2009).
[CrossRef]

Netterfield, R. P.

Ohmi, M.

Schellekens, P. H. J.

M. J. Jansen, H. Haitjema, and P. H. J. Schellekens, “A scanning wafer thickness and flatness interferometer,” Proc. SPIE 5856, 334–343 (2004).
[CrossRef]

Schurz, D.

D. Schurz, W. W. Flack, and R. L. Hsieh, “Dual side lithography measurement, precision and accuracy,” Proc. SPIE 5752, 97–105 (2005).

Smith, L. M.

So, H.-Y.

G. Nam, C.-S. Kang, H.-Y. So, and J. Choi, “An uncertainty evaluation for multiple measurements by GUM, III: using a correlation coefficient,” Accredit. Qual. Assur. 14(1), 43–47 (2009).
[CrossRef]

Tajiri, H.

Tay, S. P.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Wallace, R. M.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Wilk, G. D.

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Accredit. Qual. Assur. (1)

G. Nam, C.-S. Kang, H.-Y. So, and J. Choi, “An uncertainty evaluation for multiple measurements by GUM, III: using a correlation coefficient,” Accredit. Qual. Assur. 14(1), 43–47 (2009).
[CrossRef]

Appl. Opt. (6)

Appl. Phys. Lett. (1)

Z. H. Lu, J. P. McCaffrey, B. Brar, G. D. Wilk, R. M. Wallace, L. C. Feldman, and S. P. Tay, “SiO2 film thickness metrology by x-ray photoelectron spectroscopy,” Appl. Phys. Lett. 71(19), 2764–2766 (1997).
[CrossRef]

Opt. Lett. (3)

Proc. SPIE (2)

D. Schurz, W. W. Flack, and R. L. Hsieh, “Dual side lithography measurement, precision and accuracy,” Proc. SPIE 5752, 97–105 (2005).

M. J. Jansen, H. Haitjema, and P. H. J. Schellekens, “A scanning wafer thickness and flatness interferometer,” Proc. SPIE 5856, 334–343 (2004).
[CrossRef]

Other (1)

J. Pei, F. L. Degertekin, B. V. Honein, B. T. Khuri-Yakub, and K. C. Sarawat, “In-situ thin film thickness measurement using ultrasonics waves,” Proc. Ultrasonics Symposium, 1237–1240 (1994).

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Figures (3)

Fig. 1
Fig. 1

Optical layout of the measurement system. (EDFA: Er doped fiber amplifier, BS: beam splitter, M: mirror, CL: collimation lens, OSA: optical spectrum analyzer)

Fig. 2
Fig. 2

Spectrum of the optical comb in use: (a) full spectrum of the optical comb, (b) spectrum in the wavelength range 1535 to 1545 nm.

Fig. 3
Fig. 3

Interference spectra and discrete Fourier transform information: (a) interference spectrum of Ray 1, (b) interference spectrum of Ray 2, and (c) discrete Fourier transform of their interference spectra.

Tables (2)

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Table 1 Measurement Results of a Silicon Wafer

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Table 2 Uncertainty Evaluation

Equations (5)

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I ( Δ ) = I 0 ( 1 + γ cos ( 2 π c Δ f ) )
Δ = c P
T = (C B) (D A)
N = (C B) / T
r = u B (x) 2 / ( u A (x) 2 + u B (x) 2 )

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