Abstract

One of the main challenges for 3D interconnect metrology of bonded wafers is measuring through opaque silicon wafers using conventional optical microscopy. We demonstrate here the use infrared microscopy, enhanced by implementing the differential interference contrast (DIC) technique, to measure the wafer bonding overlay. A pair of two dimensional symmetric overlay marks were processed at both the front and back sides of thinned wafers to evaluate the bonding overlay. A self-developed analysis algorithm and theoretical fitting model was used to map the overlay error between the bonded wafers and the interconnect structures. The measurement accuracy was found to be better than 1.0 micron.

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References

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  1. ITRS Metrology2011.
  2. S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
    [CrossRef]
  3. R. Yu, “High density 3D integration,” IBM Research Report, Electrical Engineering RC 24516 (W0806–114), June 26 (2008).
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  5. P. Garrou, C. Bower, and P. Ramm, Handbook of 3D Integration-Volume1-Technology and Applications of 3D Integrated Circuits, Chapter 12 (Wiley-VCH Verlag GmbH & Co. KGaA, 2008).
  6. Y. Xie, J. Cong, and S. Sapatnekar, Three-Dimensional Integrated Circuit Design, Chapter 8 (Springer Science + Business Media, LLC 2010).
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    [CrossRef]
  8. A. Trigg, “Applications of Infrared Microscopy to IC and MEMS Packaging,” IEEE Trans. Electron. Packag. Manuf.26(3), 232–238 (2003).
    [CrossRef]
  9. J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).
  10. A. C. Rudack, L. W. Kong, and G. G. Baker, “Infrared Microscopy for Overlay and Defect Metrology on 3D-Interconnect Bonded Wafers,” Advanced Semiconductor Manufacturing Conference (ASMC), IEEE/SEMI, 347–352 (2010).
    [CrossRef]
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    [PubMed]
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    [CrossRef] [PubMed]
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    [PubMed]
  17. Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
    [CrossRef]
  18. Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-Focus Technique for nano-scale grating pitch and linewidth analysis,” Opt. Express13(18), 6699–6708 (2005).
    [CrossRef] [PubMed]
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    [CrossRef]
  20. W. D. Hopewell, R. R. Jackson, J. C. Shaw, and T. G. V. Kessel, “Latent-image control of lithography tools,” US patent 5,124,927 (1992).
  21. Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
    [CrossRef]

2012

Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
[CrossRef]

2007

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

2006

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
[CrossRef]

2005

2003

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

A. Trigg, “Applications of Infrared Microscopy to IC and MEMS Packaging,” IEEE Trans. Electron. Packag. Manuf.26(3), 232–238 (2003).
[CrossRef]

2001

M. S. Elliot and W. C. K. Poon, “Conventional optical microscopy of colloidal suspensions,” Adv. Colloid Interface Sci.92(1-3), 133–194 (2001).
[CrossRef] [PubMed]

1998

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

1992

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

1990

1969

R. D. Allen, G. B. David, and G. Nomarski, “The zeiss-Nomarski differential interference equipment for transmitted-light microscopy,” Z. Wiss. Mikrosk.69(4), 193–221 (1969).
[PubMed]

1955

G. Normarski, “Microinterf’erom`etre diff’erential `a ondes polaris’ees,” J. Phys. Radium16, 9S–11S (1955).

Allen, R. D.

R. D. Allen, G. B. David, and G. Nomarski, “The zeiss-Nomarski differential interference equipment for transmitted-light microscopy,” Z. Wiss. Mikrosk.69(4), 193–221 (1969).
[PubMed]

Arnison, M. R.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

Belote, K.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Chai, T. C.

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

Chang, P. Y.

Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
[CrossRef]

Cogswell, C. J.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

Coleman, D. J.

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

Corle, T. R.

David, G. B.

R. D. Allen, G. B. David, and G. Nomarski, “The zeiss-Nomarski differential interference equipment for transmitted-light microscopy,” Z. Wiss. Mikrosk.69(4), 193–221 (1969).
[PubMed]

Dekker, R.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Elliot, M. S.

M. S. Elliot and W. C. K. Poon, “Conventional optical microscopy of colloidal suspensions,” Adv. Colloid Interface Sci.92(1-3), 133–194 (2001).
[CrossRef] [PubMed]

Frank, D. J.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Kino, G. S.

Ku, Y. S.

Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
[CrossRef]

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
[CrossRef]

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-Focus Technique for nano-scale grating pitch and linewidth analysis,” Opt. Express13(18), 6699–6708 (2005).
[CrossRef] [PubMed]

Larkin, K. G.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

Larson, P. J.

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

LaTulipe, D.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Liu, A. S.

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
[CrossRef]

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-Focus Technique for nano-scale grating pitch and linewidth analysis,” Opt. Express13(18), 6699–6708 (2005).
[CrossRef] [PubMed]

Lopata, A. D.

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

Lu, J.

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

Marinier, L.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Metrology, ITRS

ITRS Metrology2011.

Muth, W. A.

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

Nomarski, G.

R. D. Allen, G. B. David, and G. Nomarski, “The zeiss-Nomarski differential interference equipment for transmitted-light microscopy,” Z. Wiss. Mikrosk.69(4), 193–221 (1969).
[PubMed]

Normarski, G.

G. Normarski, “Microinterf’erom`etre diff’erential `a ondes polaris’ees,” J. Phys. Radium16, 9S–11S (1955).

Pellens, R.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Poon, W. C. K.

M. S. Elliot and W. C. K. Poon, “Conventional optical microscopy of colloidal suspensions,” Adv. Colloid Interface Sci.92(1-3), 133–194 (2001).
[CrossRef] [PubMed]

Posillico, D.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Shen, C.

Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
[CrossRef]

Sheppard, C. J.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

Smith, N. I.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

Smith, N. P.

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
[CrossRef]

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-Focus Technique for nano-scale grating pitch and linewidth analysis,” Opt. Express13(18), 6699–6708 (2005).
[CrossRef] [PubMed]

Starikov, A.

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

Steen, S. E.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Sutedja, B.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Topol, A. W.

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Trigg, A.

A. Trigg, “Applications of Infrared Microscopy to IC and MEMS Packaging,” IEEE Trans. Electron. Packag. Manuf.26(3), 232–238 (2003).
[CrossRef]

Trigg, A. D.

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

van Noort, W.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

van Zeijl, H.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

Wu, J.

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

Adv. Colloid Interface Sci.

M. S. Elliot and W. C. K. Poon, “Conventional optical microscopy of colloidal suspensions,” Adv. Colloid Interface Sci.92(1-3), 133–194 (2001).
[CrossRef] [PubMed]

Appl. Opt.

IEEE Trans. Electron. Packag. Manuf.

A. Trigg, “Applications of Infrared Microscopy to IC and MEMS Packaging,” IEEE Trans. Electron. Packag. Manuf.26(3), 232–238 (2003).
[CrossRef]

Int. J. Microcircuits Electron. Packag.

J. Lu, A. D. Trigg, J. Wu, and T. C. Chai, “Detecting underfill delamination and cracks in flip chip on board assemblies using infrared microscope,” Int. J. Microcircuits Electron. Packag.21(3), 231–235 (1998).

J. Micro/Nanolith. MEMS MOEMS

Y. S. Ku, P. Y. Chang, and C. Shen, “Experimental investigation of three-dimensional interconnect processing wafers,” J. Micro/Nanolith. MEMS MOEMS11(4), 043002 (2012).
[CrossRef]

J. Microsc.

M. R. Arnison, K. G. Larkin, C. J. Sheppard, N. I. Smith, and C. J. Cogswell, “Linear phase imaging using differential interference contrast microscopy,” J. Microsc.214, 7–12 (2003).
[PubMed]

J. Phys. Radium

G. Normarski, “Microinterf’erom`etre diff’erential `a ondes polaris’ees,” J. Phys. Radium16, 9S–11S (1955).

Microelectron. Eng.

L. Marinier, W. van Noort, R. Pellens, B. Sutedja, R. Dekker, and H. van Zeijl, “Front- to back-side overlay optimization after wafer bonding for 3D integration,” Microelectron. Eng.83(4–9), 1229–1232 (2006).
[CrossRef]

S. E. Steen, D. LaTulipe, A. W. Topol, D. J. Frank, K. Belote, and D. Posillico, “Overlay as the key to drive wafer scale 3D integration,” Microelectron. Eng.84(5-8), 1412–1415 (2007).
[CrossRef]

Opt. Eng.

Y. S. Ku, A. S. Liu, and N. P. Smith, “Through-focus technique for grating linewidth analysis with nanometer sensitivity,” Opt. Eng.45(12), 123602 (2006).
[CrossRef]

A. Starikov, D. J. Coleman, P. J. Larson, A. D. Lopata, and W. A. Muth, “Accuracy of overlay measurements: tool and mark asymmetry effects,” Opt. Eng.31(6), 1298 (1992).
[CrossRef]

Opt. Express

Z. Wiss. Mikrosk.

R. D. Allen, G. B. David, and G. Nomarski, “The zeiss-Nomarski differential interference equipment for transmitted-light microscopy,” Z. Wiss. Mikrosk.69(4), 193–221 (1969).
[PubMed]

Other

W. D. Hopewell, R. R. Jackson, J. C. Shaw, and T. G. V. Kessel, “Latent-image control of lithography tools,” US patent 5,124,927 (1992).

ITRS Metrology2011.

R. Yu, “High density 3D integration,” IBM Research Report, Electrical Engineering RC 24516 (W0806–114), June 26 (2008).

A. Papaniko, D. Soudris, and R. Radojcic, Three Dimensional System Integration, Chapter 9 (Springer Science + Business Media LLC, 2011).

P. Garrou, C. Bower, and P. Ramm, Handbook of 3D Integration-Volume1-Technology and Applications of 3D Integrated Circuits, Chapter 12 (Wiley-VCH Verlag GmbH & Co. KGaA, 2008).

Y. Xie, J. Cong, and S. Sapatnekar, Three-Dimensional Integrated Circuit Design, Chapter 8 (Springer Science + Business Media, LLC 2010).

A. C. Rudack, L. W. Kong, and G. G. Baker, “Infrared Microscopy for Overlay and Defect Metrology on 3D-Interconnect Bonded Wafers,” Advanced Semiconductor Manufacturing Conference (ASMC), IEEE/SEMI, 347–352 (2010).
[CrossRef]

A. C. Diebold, Handbook of Silicon Semiconductor Metrology (CRC Press, 2001), p. 435.

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Figures (13)

Fig. 1
Fig. 1

Schematic of the reflection-type infrared differential interference contrast (DIC) microscope.

Fig. 2
Fig. 2

Process flow used to test the overlay of the front- and back-side wafer bonds.

Fig. 3
Fig. 3

(a) Front-side overlay marks b) Back-side overlay marks (c) Infrared bright-field images taken from wafer front-side and back-side separately.

Fig. 4
Fig. 4

The layout of the 12-inch bonding overlay test wafer. Each printed die size was 32 x 32 mm. There were four quadrants for each die and the test patterns were repeated in the third quadrant of each die.

Fig. 5
Fig. 5

The arrangement of the Normarski prism shear direction qs. (45°), with respect to the Y-axis of the overlay mark.

Fig. 6
Fig. 6

DIC image of (a) the back-side and (b) the front-side overlay mark in focus.

Fig. 7
Fig. 7

Two template masks excluding (a) an outer cross frame, and (b) an inner cross frame, within a certain acceptable range of frame linewidth. (c) & (d) The average of the different edge pairs (a) & (b), respectively.

Fig. 8
Fig. 8

Comparison of (a) the bright-field image, (b) the dark-field image, and (c) the DIC image of the upper and lower wafer surface focus positions.

Fig. 9
Fig. 9

TIS data taken by single focus Nomarski DIC microscope (9(a) and 9(b)), and dual focus bright field microscope (9(c)-9(f)).

Fig. 10
Fig. 10

Vector plots showing the wafer map of TIS-corrected overlay error after the wafer bonding process. Data was obtained using (a) DIC microscopy, and (b) bright-field microscopy.

Fig. 11
Fig. 11

Comparison of measuring overlay point-by-point (bright-field vs. DIC) for both X and Y.

Fig. 12
Fig. 12

Map of the bonding wafer warpage versus overlay.

Fig. 13
Fig. 13

The measurement validation: a cross section SEM for die site 2-2.

Tables (1)

Tables Icon

Table 1 Results of the wafer bonding overlay analysis.

Equations (4)

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

I= R 0 2 cos 2 θ 1 + R 0 2 cos 2 θ 2 +2 R 0 2 cos θ 1 cos θ 2 cosΔϕ
I= R 0 2 (1cosΔϕ)
DX = T X + E X X R X Y + e X
DY = T Y + E Y Y + R Y X + e Y

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