Abstract

We demonstrate a fabrication procedure for the direct integration of micro-ball lenses on planar integrated optical channel waveguide chips with the aim to reduce the divergence of light that arises from the waveguide in both horizontal and vertical directions. Fabrication of the lenses is based on photoresist reflow which is a procedure that allows for the use of photolithography for careful alignment of the lenses with respect to the waveguides and enables mass production. We present in detail the design and fabrication procedures. Optical characterization of the fabricated micro-ball lenses demonstrates a good performance in terms of beam-size reduction and beam shape. The beam half divergence angle of 1544 nm light is reduced from 12.4 ° to 1.85 °.

© 2015 Optical Society of America

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References

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  1. B. I. Akca, B. Považay, A. Alex, K. Wörhoff, R. M. de Ridder, W. Drexler, and M. Pollnau, “Miniature spectrometer and beam splitter for an optical coherence tomography on a silicon chip,” Opt. Express 21(14), 16648–16656 (2013).
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
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    [Crossref]
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    [Crossref] [PubMed]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref]
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    [Crossref] [PubMed]
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    [Crossref] [PubMed]
  13. C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
    [Crossref]
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    [Crossref]
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    [Crossref]
  17. R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).
  18. O. Svelto, Principles of Lasers, 4th ed. (Springer, 2010).

2014 (1)

2013 (1)

2011 (1)

2010 (1)

2009 (1)

2008 (1)

C. Gmachl, “Plasmonics - a sharper approach,” Nat. Photonics 2(9), 524–525 (2008).
[Crossref]

2007 (1)

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

2005 (1)

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

2001 (1)

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

1999 (1)

1998 (1)

1997 (2)

R. P. Ratowsky, L. Yang, R. J. Deri, K. W. Chang, J. S. Kallman, and G. Trott, “Laser diode to single-mode fiber ball lens coupling efficiency: full-wave calculation and measurements,” Appl. Opt. 36(15), 3435–3438 (1997).
[Crossref] [PubMed]

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

1994 (1)

O. Mitomi, K. Kasaya, and H. Miyazawa, “Design of a single-mode tapered waveguide for low-loss chip-to-fiber coupling,” IEEE J. Quantum Electron. 30(8), 1787–1793 (1994).
[Crossref]

1993 (1)

R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).

Akca, B. I.

Alex, A.

Baclig, A. C.

Baets, R.

G. Yurtsever, N. Weiss, J. Kalkman, T. G. van Leeuwen, and R. Baets, “Ultra-compact silicon photonic integrated interferometer for swept-source optical coherence tomography,” Opt. Lett. 39(17), 5228–5231 (2014).
[Crossref] [PubMed]

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

Bogaerts, W.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Brodsky, C. J.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Caspers, P. J.

Chang, K. W.

Cheung, Y. M.

Y. M. Cheung and C. H. Yiu, “Simulation of the alignment sensitivity on the coupling efficiency of a ball-lens capped TO-Can laser diode source into a single-mode fiber,” in Proceedings of the 4th International Symposium on Electronic Materials and Packaging (IEEE, 2002), pp. 197–203.
[Crossref]

Chien, C. H.

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Choo-Smith, L. P.

Claes, T.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Dammel, R. R.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

de Ridder, R. M.

Deri, R. J.

Diazuribe, R.

R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).

Drexler, W.

Driessen, A.

Gmachl, C.

C. Gmachl, “Plasmonics - a sharper approach,” Nat. Photonics 2(9), 524–525 (2008).
[Crossref]

Groen, F.

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

Hsieh, C. C.

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Huang, J. C.

Ismail, N.

Kalkman, J.

Kallman, J. S.

Kasaya, K.

O. Mitomi, K. Kasaya, and H. Miyazawa, “Design of a single-mode tapered waveguide for low-loss chip-to-fiber coupling,” IEEE J. Quantum Electron. 30(8), 1787–1793 (1994).
[Crossref]

Lambek, P. V.

Lehar, O. P.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Meyer, S.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Mitomi, O.

O. Mitomi, K. Kasaya, and H. Miyazawa, “Design of a single-mode tapered waveguide for low-loss chip-to-fiber coupling,” IEEE J. Quantum Electron. 30(8), 1787–1793 (1994).
[Crossref]

Miyazawa, H.

O. Mitomi, K. Kasaya, and H. Miyazawa, “Design of a single-mode tapered waveguide for low-loss chip-to-fiber coupling,” IEEE J. Quantum Electron. 30(8), 1787–1793 (1994).
[Crossref]

Moerman, I.

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

O’Faolain, L.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Ortegamartinez, R.

R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).

Pan, C. T.

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Pollnau, M.

Považay, B.

Puppels, G. J.

Ratowsky, R. P.

Roseteaguilar, M.

R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).

Scheerlinck, S.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Schrauwen, J.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Shen, S. C.

Sher, K. L.

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Smit, M. K.

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

Spak, M. A.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Sun, F.

Taillaert, D.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

Trott, G.

Van Laere, F.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

van Leeuwen, T. G.

Van Thourhout, D.

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

VanDaele, P.

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

Wei, C. L.

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

Weiss, N.

Willson, C. G.

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Wilson, R. G.

Wörhoff, K.

Yang, C. M.

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Yang, L.

Yiu, C. H.

Y. M. Cheung and C. H. Yiu, “Simulation of the alignment sensitivity on the coupling efficiency of a ball-lens capped TO-Can laser diode source into a single-mode fiber,” in Proceedings of the 4th International Symposium on Electronic Materials and Packaging (IEEE, 2002), pp. 197–203.
[Crossref]

Yurtsever, G.

Appl. Opt. (2)

IEEE J. Quantum Electron. (1)

O. Mitomi, K. Kasaya, and H. Miyazawa, “Design of a single-mode tapered waveguide for low-loss chip-to-fiber coupling,” IEEE J. Quantum Electron. 30(8), 1787–1793 (1994).
[Crossref]

IEEE Photonics Technol. Lett. (1)

F. Van Laere, T. Claes, J. Schrauwen, S. Scheerlinck, W. Bogaerts, D. Taillaert, L. O’Faolain, D. Van Thourhout, and R. Baets, “Compact focusing grating couplers for silicon-on-insulator integrated circuits,” IEEE Photonics Technol. Lett. 19(23), 1919–1921 (2007).
[Crossref]

J. Lightwave Technol. (2)

C. L. Wei, F. Groen, M. K. Smit, I. Moerman, P. VanDaele, and R. Baets, “Integrated optical elliptic couplers: modeling, design, and applications,” J. Lightwave Technol. 15(5), 906–912 (1997).
[Crossref]

K. Wörhoff, P. V. Lambek, and A. Driessen, “Design, tolerance analysis, and fabrication of silicon oxynitride based planar optical waveguides for communication devices,” J. Lightwave Technol. 17(8), 1401–1407 (1999).
[Crossref]

Nat. Photonics (1)

C. Gmachl, “Plasmonics - a sharper approach,” Nat. Photonics 2(9), 524–525 (2008).
[Crossref]

Opt. Express (2)

Opt. Lett. (3)

Proc. SPIE (1)

O. P. Lehar, M. A. Spak, S. Meyer, R. R. Dammel, C. J. Brodsky, and C. G. Willson, “Resist rehydration during thick film processing,” Proc. SPIE 4345, 463–474 (2001).
[Crossref]

Rev. Mex. Fis. (1)

R. Diazuribe, M. Roseteaguilar, and R. Ortegamartinez, “Position sensing of a Gaussian-beam with a power-meter and a knife edge,” Rev. Mex. Fis. 39(3), 484–492 (1993).

Sens. Actuators A Phys. (1)

C. H. Chien, C. T. Pan, C. C. Hsieh, C. M. Yang, and K. L. Sher, “A study of the geometry of microball lens arrays using the novel batch-fabrication technique,” Sens. Actuators A Phys. 122(1), 55–63 (2005).
[Crossref]

Other (3)

MicroChemicals, “thick resist processing,” http://www.microchemicals.com/technical_information/thick_resist_processing.pdf , Accessed 01–04–2015, 2015.

O. Svelto, Principles of Lasers, 4th ed. (Springer, 2010).

Y. M. Cheung and C. H. Yiu, “Simulation of the alignment sensitivity on the coupling efficiency of a ball-lens capped TO-Can laser diode source into a single-mode fiber,” in Proceedings of the 4th International Symposium on Electronic Materials and Packaging (IEEE, 2002), pp. 197–203.
[Crossref]

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Figures (6)

Fig. 1
Fig. 1 (a) Schematic layout of a micro-ball lens integrated onto a SiON channel waveguide chip. (b) Schematic cross-section of the photoresist cylinder and its reflowed structure. (c) Diagram allows determining cylinder radius R (thin black dashed curves) and height H (thin blue solid curves) for a desired lens radius r and center height h. The thick dashed red lines show that a lens with r = 51 µm, h = 23 µm is obtained from a cylinder with R ≈45 µm, H ≈70 µm.
Fig. 2
Fig. 2 Process flow chart for etching the platform on which the lenses are to be fabricated.
Fig. 3
Fig. 3 Process flow chart for the fabrication of a photo-definable micro-ball lens array aligned to the channel waveguides.
Fig. 4
Fig. 4 (a) Bird's-eye view of a fabricated micro-ball lens array before dicing the chip. There are 5 waveguides at 250 µm spacing in this image. The outline of the middle lens and its mirror image has been drawn to guide the eye. (b) Top view of a micro-ball lens array after dicing. (c) Geometry layout used to calculate the lens center height h=l/(2cos(θ)) from the observed distance l and observing angle θ.
Fig. 5
Fig. 5 Beam profile (at λ = 1544 nm) behind a micro-ball lens measured with a knife-edge setup at 1.2 mm away from the waveguide end. (a) and (c) display the measured power and their fitting in the horizontal (x) and vertical (y) direction, respectively. (b) and (d) display the derivative of the measured data and its Gaussian fitting of (a) and (c), respectively.
Fig. 6
Fig. 6 Beam radius (1/e2 radius) measurements in x direction for different waveguide-lens distances with a knife-edge setup. z is the beam propagation direction and z = 0 is the end facet of the waveguide. The distance between the waveguide end facet and the lens center is d. The dashed line is the simulated beam size from a waveguide without a micro-ball lens. The half divergence angle of this beam is 12.4 degree. The black, red, and blue lines are the fitted results of the measurements with d equal to 58 µm, 65 µm, and 72 µm, respectively.

Equations (7)

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

V= V cylinder =π R 2 H.
V= V balllens = 2 3 π r 3 +π r 2 h 1 3 π h 3 .
r 2 = h 2 + R 2 .
f= n 2( n1 ) r,
P= P 0 + P max 2 erf( 2 ( x x 0 ) w ),
w( z )= w 0 1+ ( z z 0 ) 2 z R ; with z R = π w 0 2 λ ,
tan( θ )= λ π w 0 .

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