Abstract

We describe the experimental evaluation of a shearing interferometer concept for at-wavelength testing of extreme-ultraviolet optics. The concept is based on the Ronchi test, which has been modified by a new design for entrance and exit gratings to suppress disturbing higher-order interference patterns. The interferometer concept has been tested on an experimental setup, of which all relevant parameters have been scaled from extreme-ultraviolet to visible-light wavelengths. A Twyman–Green interferometer has been integrated into the setup for comparison with the improved Ronchi test. A systematic difference of 7–12 mλ rms has been found between wave fronts measured with the improved Ronchi test and with the Twyman–Green interferometer. Possible error sources have been analyzed. The accuracy of the interferometer is estimated to be 10 mλ rms.

© 2001 Optical Society of America

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References

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  1. R. H. Stulen, D. W. Sweeney, “Extreme ultraviolet lithography,” IEEE J. Quantum Electron. 35, 694–699 (1999).
    [CrossRef]
  2. J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
    [CrossRef]
  3. P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).
  4. A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
    [CrossRef]
  5. M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
    [CrossRef]
  6. D. Malacara, “Twyman–Green interferometer,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 51–94.
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    [CrossRef]
  11. J. Braat, A. J. E. M. Janssen, “An improved Ronchi test with extended source,” J. Opt. Soc. A 16, 131–140 (1999).
    [CrossRef]
  12. P. Hariharan, B. F. Oreb, T. Eiju, “Digital phase-shifting interferometry: a simple error-compensating phase calculation algorithm,” Appl. Opt. 26, 2504–2506 (1987).
    [CrossRef] [PubMed]
  13. J. E. Greivenkamp, J. H. Bruning, “Phase shifting interferometers,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 501–598.
  14. G. Harbers, P. J. Kunst, G. W. Leibbrandt, “Analysis of lateral shearing interferograms by use of Zernike polynomials,” Appl. Opt. 35, 6162–6172 (1996).
    [CrossRef] [PubMed]
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    [CrossRef] [PubMed]

1999 (2)

R. H. Stulen, D. W. Sweeney, “Extreme ultraviolet lithography,” IEEE J. Quantum Electron. 35, 694–699 (1999).
[CrossRef]

J. Braat, A. J. E. M. Janssen, “An improved Ronchi test with extended source,” J. Opt. Soc. A 16, 131–140 (1999).
[CrossRef]

1996 (3)

G. Harbers, P. J. Kunst, G. W. Leibbrandt, “Analysis of lateral shearing interferograms by use of Zernike polynomials,” Appl. Opt. 35, 6162–6172 (1996).
[CrossRef] [PubMed]

G. Leibbrandt, G. Harbers, P. J. Kunst, “Wave-front analysis with high accuracy by use of a double-grating lateral shearing interferometer,” Appl. Opt. 35, 6151–6161 (1996).
[CrossRef] [PubMed]

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

1995 (1)

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

1987 (1)

1981 (1)

1973 (1)

Attwood, D.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Batson, P.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Bjorkholm, J. E.

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Bokor, J.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Born, M.

M. Born, E. Wolf, Principles of Optics, 6th ed. (Pergamon, Oxford, 1980).

Braat, J.

J. Braat, A. J. E. M. Janssen, “An improved Ronchi test with extended source,” J. Opt. Soc. A 16, 131–140 (1999).
[CrossRef]

M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
[CrossRef]

Bresloff, C.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Bruning, J. H.

J. E. Greivenkamp, J. H. Bruning, “Phase shifting interferometers,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 501–598.

Chang, C.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Cornejo-Rodriguez, A.

A. Cornejo-Rodriguez, “Ronchi test,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 321–365.

Dekker, M.

M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
[CrossRef]

Eiju, T.

Fields, C. H.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Goldberg, K. A.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Greivenkamp, J. E.

J. E. Greivenkamp, J. H. Bruning, “Phase shifting interferometers,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 501–598.

Haney, S. J.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Harbers, G.

Hariharan, P.

Hegeman, P.

M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
[CrossRef]

Hudyma, R. M.

J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
[CrossRef]

Janssen, A. J. E. M.

J. Braat, A. J. E. M. Janssen, “An improved Ronchi test with extended source,” J. Opt. Soc. A 16, 131–140 (1999).
[CrossRef]

Krenz, K. D.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Kunst, P. J.

Lafontaine, B.

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Lee, S.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Leibbrandt, G.

Leibbrandt, G. W.

MacDowell, A. A.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Malacara, D.

D. Malacara, “Twyman–Green interferometer,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 51–94.

Naulleau, P.

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

Nissen, R. P.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Oreb, B. F.

Ray-Chaudhuri, A. K.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Schwider, J.

Sommargren, G. E.

J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
[CrossRef]

Stulen, R. H.

R. H. Stulen, D. W. Sweeney, “Extreme ultraviolet lithography,” IEEE J. Quantum Electron. 35, 694–699 (1999).
[CrossRef]

Sweatt, W. C.

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Sweeney, D. W.

R. H. Stulen, D. W. Sweeney, “Extreme ultraviolet lithography,” IEEE J. Quantum Electron. 35, 694–699 (1999).
[CrossRef]

J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
[CrossRef]

Tan, Z.

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Taylor, J. S.

J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
[CrossRef]

Tennant, D. M.

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Visser, M.

M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
[CrossRef]

Wolf, E.

M. Born, E. Wolf, Principles of Optics, 6th ed. (Pergamon, Oxford, 1980).

Wood, O. R.

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

Wyant, J. C.

Appl. Opt. (5)

IEEE J. Quantum Electron. (1)

R. H. Stulen, D. W. Sweeney, “Extreme ultraviolet lithography,” IEEE J. Quantum Electron. 35, 694–699 (1999).
[CrossRef]

J. Opt. Soc. A (1)

J. Braat, A. J. E. M. Janssen, “An improved Ronchi test with extended source,” J. Opt. Soc. A 16, 131–140 (1999).
[CrossRef]

J. Vac. Sci. Technol. B (2)

J. E. Bjorkholm, A. A. MacDowell, O. R. Wood, Z. Tan, B. Lafontaine, D. M. Tennant, “Phase-measuring interferometry using extreme ultraviolet radiation,” J. Vac. Sci. Technol. B 13, 2919–2922 (1995).
[CrossRef]

A. K. Ray-Chaudhuri, K. D. Krenz, R. P. Nissen, S. J. Haney, C. H. Fields, W. C. Sweatt, A. A. MacDowell, “Initial results from an extreme ultraviolet interferometer operating with a compact laser plasma source,” J. Vac. Sci. Technol. B 14, 3964–3968 (1996).
[CrossRef]

Other (7)

M. Visser, M. Dekker, P. Hegeman, J. Braat, “Extended-source interferometry for at-wavelength test of EUV-optics,” in Emerging Lithographic Technologies III, Y. Vladimirsky, ed., Proc. SPIE3676, 253–263 (1999).
[CrossRef]

D. Malacara, “Twyman–Green interferometer,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 51–94.

A. Cornejo-Rodriguez, “Ronchi test,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 321–365.

J. S. Taylor, G. E. Sommargren, D. W. Sweeney, R. M. Hudyma, “The fabrication and testing of optics for EUV projection lithography,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 580–590 (1998).
[CrossRef]

P. Naulleau, K. A. Goldberg, S. Lee, C. Chang, C. Bresloff, P. Batson, D. Attwood, J. Bokor, “Characterization of the accuracy of EUV phase-shifting point diffraction interferometry,” in Emerging Lithographic Technologies II, Y. Vladimirsky, ed., Proc. SPIE3331, 115–123 (1998).

M. Born, E. Wolf, Principles of Optics, 6th ed. (Pergamon, Oxford, 1980).

J. E. Greivenkamp, J. H. Bruning, “Phase shifting interferometers,” in Optical Shop Testing, 2nd ed., D. Malacara, ed. (Wiley, New York, 1992), pp. 501–598.

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Figures (4)

Fig. 1
Fig. 1

Layout of entrance and exit gratings (left) and measured shearing interferograms (right) for the Gratings R, P, and T in the visible-light setup. Grating R: only (0, 1) and (0, -1) interference patterns are present; no higher-order interferences overlap. Grating P: the (0, ±3) and (0, ±5) interference patterns are suppressed by phase steps ΔP in = P/6 and ΔP out = P/10; the (-1, 0) and (0, 1) interference patterns overlap, slightly shifted with respect to each other. Grating T: the (-1, 1) interference pattern is disturbed by the higher-order interference patterns (-3, -1), (1, 3), (-5, -3), (3, 5), … .

Fig. 2
Fig. 2

Schematics of the Ronchi experimental setup and the Twyman–Green interferometer.

Fig. 3
Fig. 3

Zernike coefficients up to n + |m| ≤ 8 (without the piston, tilt, and defocus terms, with 5, 6, 7, 8, … ,25 = A 2,2, A 2,-2, A 3,1, A 3,-1A 8,0).

Fig. 4
Fig. 4

Geometry of the Ronchi test with a spherical mirror under test. The source area and the corresponding detection area are marked denoted Ss and Sd, respectively. The pupil coordinates on the mirror are (X, Y) and the field coordinates are (x, y).

Tables (6)

Tables Icon

Table 1 Parameters of Visible-Light and EUV Setups and Magnification M

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Table 2 Total rms Wave-Front Deviation and Standard Deviation σ for Gratings R, P, and T (Averaged over Five Measurement Series) and TG (Averaged over Eight Measurement Series)a

Tables Icon

Table 3 Difference Wave Front among Gratings R, P, and T and the TG, Calculated by Subtraction of the Zernike Coefficients Separately from One Anothera

Tables Icon

Table 4 Comparison of the Two Shear Ratios with a 1-Pixel Differencea

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Table 5 rms Value Calculated with Dimensions D = 8 and D = 12 for the Gratings R, T, and P

Tables Icon

Table 6 Summary of Systematic Errors

Equations (11)

Equations on this page are rendered with MathJax. Learn more.

WX, Y; x, y=A2,0122X2+Y2-1x2+y2+A2,2X2-Y2x2-y2+4XYxy,
ΔWXX, Y; x, y=WX-X0, Y; x, y-WX, Y; x, y=-22 A2,0x2+y2+2A2,2x2-y2X0X-4A2,2xyX0Y+A2,02x2+y2+A2,2x2-y2X02, ΔWYX, Y; x, y=WX, Y-Y0; x, y-WX, Y; x, y=-22 A2,0x2+y2-2A2,2x2-y2Y0Y-4A2,2xyY0X+A2,02x2+y2-A2,2x2-y2Y02.
dIXX, Y; x, y=I0x, y1+m cosk0ΔWX+ϕXdxdy, dIYX, Y; x, y=I0x, y1+m cosk0ΔWY+ϕYdxdy,
IXX, Y=Sdcosk0-22 A2,0x2+y2-2A2,2x2-y2X0X-4A2,2xyX0Y+A2,02x2+y2+A2,2x2-y2X02+ϕXdxdy,
IYX, Y=Sdcosk0-22 A2,0x2+y2+2A2,2x2-y2Y0Y-4A2,2xyY0X+A2,02x2+y2-A2,2x2-y2Y02+ϕYdxdy.
IXX, Y=SdcosAXx, yX+BXx, yY+CXx, y+ϕXdxdy,
IYX, Y=SdcosAYx, yY+BYx, yX+CYx, y+ϕYdxdy,
WX, Y=A2,0122X2+Y2-1+A2,2X2-Y2+A2,-22XY,
ΔWXX, Y=-X022 A2,0+2A2,2X-2X0A2,-2Y, ΔWYX, Y=-Y022 A2,0-2A2,2Y-2Y0A2,-2X.
ΔWX1, 0=-X022 A2,0+2A2,2, ΔWY1, 0=-2Y0A2,-2, ΔWX0, 1=-2X0A2,-2, ΔWY0, 1=-Y022 A2,0-2A2,2.
A2,0=-ΔWX1, 0-ΔWY0, 1λ8π2a, A2,2=-ΔWX1, 0+ΔWY0, 1λ8πa A2,-2=-ΔWY1, 0-ΔWX0, 1λ8πa,

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