Abstract

The control of defect mediated optical absorption at a wavelength of 1550nm via charge state manipulation is demonstrated using optical absorption measurements of indium doped Silicon-On-Insulator (SOI) rib waveguides. These measurements introduce the potential for modulation of waveguide transmission by using the local depletion and injection of free-carriers to change deep-level occupancy. The extinction ratio and modulating speed are simulated for a proposed device structure. A ‘normally-off’ depletion modulator is described with an extinction coefficient limited to 5 dB/cm and switching speeds in excess of 1 GHz. For a carrier injection modulator a fourfold enhancement in extinction ratio is provided relative to free carrier absorption alone. This significant improvement in performance is achieved with negligible increase in driving power but slightly degraded switching speed.

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References

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  1. A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
    [CrossRef]
  2. M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
    [CrossRef]
  3. Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
    [CrossRef]
  4. H. Y. Fan and A. K. Ramdas, “Infrared absorption and photoconductivity in irradiated silicon,” J. Appl. Phys. 30(8), 1127–1134 (1959).
    [CrossRef]
  5. C. S. Chen and J. C. Corelli, “Infrared spectroscopy of divacancy-associated radiation-induced absorption bands in silicon,” Phys. Rev. B 5(4), 1505–1517 (1972).
    [CrossRef]
  6. D. Logan, P. E. Jessop, A. P. Knights, R. M. Gwilliam, and M. P. Halsall, “The effect of doping type and concentration on optical absorption via implantation induced defects in silicon-on-insulator waveguides.” in COMMAD 2008 IEEE Proc. Conf. on Optoelectronic and Microelectronic Materials and Devices. (Sydney, Australia, 2008). pp. 152–5.
  7. E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
    [CrossRef]
  8. M. J. Keevers and M. A. Green, “Efficiency improvements of silicon solar cells by the Impurity photovoltaic effect,” J. Appl. Phys. 75(8), 4022–4031 (1994).
    [CrossRef]
  9. G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
    [CrossRef]
  10. P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
    [CrossRef]
  11. Silvaco Data Systems Inc, © 1984–2008. [online]. Available: www.silvaco.com .
  12. RSoft Design Group, Inc., © 2002. [online]. Available: www.rsoftdesign.com .
  13. K. Dieter, Schroder, Semiconductor Material and Device Characterization. (John Wiley & Sons, 2006). p. 255–8.
  14. A. Sato, K. Suzuki, H. Horie, and T. Sugii, “Determination of Solid Solubility Limit of In and Sb in Si using Bonded Silicon-On-Insulator (SOI) Substrate.” in Proc. IEEE 1995 Int. Conf. on Microelectronic Test Structures. (Nara, Japan, vol. 8, 1995) pp. 259–263.
  15. J. Liu, U. Jeong, S. Mehta, J. Sherbondy, A. Lo, K. Ha Shim, and J. Eun Lim, “Investigation of Indium Activation by C-V Measurement.” in Proc. IEEE Int. Conf. on Ion Implantation Technology, H. Ryssel et al., ed. (Alpbach, Austria, 2000) pp. 66–69.

2007 (1)

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

2006 (3)

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

2000 (1)

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

1994 (1)

M. J. Keevers and M. A. Green, “Efficiency improvements of silicon solar cells by the Impurity photovoltaic effect,” J. Appl. Phys. 75(8), 4022–4031 (1994).
[CrossRef]

1983 (1)

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

1972 (1)

C. S. Chen and J. C. Corelli, “Infrared spectroscopy of divacancy-associated radiation-induced absorption bands in silicon,” Phys. Rev. B 5(4), 1505–1517 (1972).
[CrossRef]

1959 (1)

H. Y. Fan and A. K. Ramdas, “Infrared absorption and photoconductivity in irradiated silicon,” J. Appl. Phys. 30(8), 1127–1134 (1959).
[CrossRef]

Bradley, J. D. B.

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

Brotherton, S. D.

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

Chen, C. S.

C. S. Chen and J. C. Corelli, “Infrared spectroscopy of divacancy-associated radiation-induced absorption bands in silicon,” Phys. Rev. B 5(4), 1505–1517 (1972).
[CrossRef]

Cheung, W. Y.

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

Chow, C. W.

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

Claeys, C.

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

Coleman, P. G.

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

Corelli, J. C.

C. S. Chen and J. C. Corelli, “Infrared spectroscopy of divacancy-associated radiation-induced absorption bands in silicon,” Phys. Rev. B 5(4), 1505–1517 (1972).
[CrossRef]

Deneault, S.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Doylend, J. K.

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

Fan, H. Y.

H. Y. Fan and A. K. Ramdas, “Infrared absorption and photoconductivity in irradiated silicon,” J. Appl. Phys. 30(8), 1127–1134 (1959).
[CrossRef]

Foster, P. J.

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

Gale, I.

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

Gan, F.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Gaubas, E.

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

Geis, M. W.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Gill, A.

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

Gou, S. H.

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

Green, M. A.

M. J. Keevers and M. A. Green, “Efficiency improvements of silicon solar cells by the Impurity photovoltaic effect,” J. Appl. Phys. 75(8), 4022–4031 (1994).
[CrossRef]

Grein, M. E.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Jessop, P. E.

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

Kaertner, F. X.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Keevers, M. J.

M. J. Keevers and M. A. Green, “Efficiency improvements of silicon solar cells by the Impurity photovoltaic effect,” J. Appl. Phys. 75(8), 4022–4031 (1994).
[CrossRef]

Knights, A. P.

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

Lennon, D. M.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Liu, Y.

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

Lyszczarz, T. M.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Mascher, P.

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

Ohyama, H.

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

Parker, G. J.

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

Ramdas, A. K.

H. Y. Fan and A. K. Ramdas, “Infrared absorption and photoconductivity in irradiated silicon,” J. Appl. Phys. 30(8), 1127–1134 (1959).
[CrossRef]

Schulein, R. T.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Simoen, E.

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

Spector, S. J.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Tsang, H. K.

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

Yoon, J. U.

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

IEEE Photon. Technol. Lett. (2)

M. W. Geis, S. J. Spector, M. E. Grein, R. T. Schulein, J. U. Yoon, D. M. Lennon, S. Deneault, F. Gan, F. X. Kaertner, and T. M. Lyszczarz, “CMOS-compatible all-Si high-speed waveguide photodiodes with high responsivity in near-infrared communication band,” IEEE Photon. Technol. Lett. 19(3), 152–154 (2007).
[CrossRef]

Y. Liu, C. W. Chow, W. Y. Cheung, and H. K. Tsang, “In-line channel power monitor based on Helium ion implantation in silicon-on-insulator waveguides,” IEEE Photon. Technol. Lett. 18(17), 1882–1884 (2006).
[CrossRef]

J. Appl. Phys. (4)

H. Y. Fan and A. K. Ramdas, “Infrared absorption and photoconductivity in irradiated silicon,” J. Appl. Phys. 30(8), 1127–1134 (1959).
[CrossRef]

M. J. Keevers and M. A. Green, “Efficiency improvements of silicon solar cells by the Impurity photovoltaic effect,” J. Appl. Phys. 75(8), 4022–4031 (1994).
[CrossRef]

G. J. Parker, S. D. Brotherton, I. Gale, and A. Gill, “Measurement of concentration and photoionization cross section of indium in silicon,” J. Appl. Phys. 54(7), 3926–3929 (1983).
[CrossRef]

P. J. Foster, J. K. Doylend, P. Mascher, A. P. Knights, and P. G. Coleman, “Optical attenuation in defect-engineered silicon rib waveguides,” J. Appl. Phys. 99(7), 073101 (2006).
[CrossRef]

J. Vac. Sci. Technol. A (1)

A. P. Knights, J. D. B. Bradley, S. H. Gou, and P. E. Jessop, “Silicon-on-insulator waveguide photodetector with self-ion-implantation engineered-enhanced infrared response,” J. Vac. Sci. Technol. A 24(3), 783–786 (2006).
[CrossRef]

Nucl. Instrum. Methods Phys. Res. A (1)

E. Simoen, C. Claeys, E. Gaubas, and H. Ohyama, “Impact of the divacancy on the generation-recombination properties of 10 MeV proton irradiated Float-Zone silicon diodes,” Nucl. Instrum. Methods Phys. Res. A 439(2-3), 310–318 (2000).
[CrossRef]

Phys. Rev. B (1)

C. S. Chen and J. C. Corelli, “Infrared spectroscopy of divacancy-associated radiation-induced absorption bands in silicon,” Phys. Rev. B 5(4), 1505–1517 (1972).
[CrossRef]

Other (6)

D. Logan, P. E. Jessop, A. P. Knights, R. M. Gwilliam, and M. P. Halsall, “The effect of doping type and concentration on optical absorption via implantation induced defects in silicon-on-insulator waveguides.” in COMMAD 2008 IEEE Proc. Conf. on Optoelectronic and Microelectronic Materials and Devices. (Sydney, Australia, 2008). pp. 152–5.

Silvaco Data Systems Inc, © 1984–2008. [online]. Available: www.silvaco.com .

RSoft Design Group, Inc., © 2002. [online]. Available: www.rsoftdesign.com .

K. Dieter, Schroder, Semiconductor Material and Device Characterization. (John Wiley & Sons, 2006). p. 255–8.

A. Sato, K. Suzuki, H. Horie, and T. Sugii, “Determination of Solid Solubility Limit of In and Sb in Si using Bonded Silicon-On-Insulator (SOI) Substrate.” in Proc. IEEE 1995 Int. Conf. on Microelectronic Test Structures. (Nara, Japan, vol. 8, 1995) pp. 259–263.

J. Liu, U. Jeong, S. Mehta, J. Sherbondy, A. Lo, K. Ha Shim, and J. Eun Lim, “Investigation of Indium Activation by C-V Measurement.” in Proc. IEEE Int. Conf. on Ion Implantation Technology, H. Ryssel et al., ed. (Alpbach, Austria, 2000) pp. 66–69.

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Figures (10)

Fig. 1
Fig. 1

The band diagram of silicon containing a constant concentration of deep acceptors Nt and varying concentrations of shallow donor levels Nd . Without the presence of shallow donors (left), many deep acceptors are unoccupied (nt takes its minimum value nt min ) and therefore electrons are capable of being optically excited from the valence band. Moving to the right, shallow donors are added in increasing concentrations. These donors supply free electrons that are trapped by the vacant deep level acceptors, thus decreasing the number of sites available for electrons to be optically excited into. On the far right, the shallow donor concentration is large enough to completely compensate the deep levels, making the optical excitation process impossible.

Fig. 2
Fig. 2

Example plots of total loss measured for each waveguide for the chip with indium implanted at a dose of 6x1014cm−2, while the various phosphorus doses are also indicated. A fit to the data using Eq. (2) provides the excess loss due to the indium doping, αd (the slope of the line, which is observed to decrease with increasing phosphorus dose).

Fig. 3
Fig. 3

Extracted values of αd vs. peak phosphorus concentration for all samples with indium implanted to a dose of 6x1013 cm−2 (black squares) and 6x1014 cm−2 (white triangles), illustrating the significant decrease of αd resulting from co-doping with phosphorus. The solid lines are fits to the data derived from Eqs. (1) and (3).

Fig. 4
Fig. 4

Occupation fraction of indium vs. donor concentration Nd for Nt = 1017 cm−3 and 1018 cm−3.

Fig. 5
Fig. 5

Cross-sectional view of the device modelled in this study, described previously by Geis et al. The p + and n + regions correspond to doping levels of 1018 cm−3, and the p + + and n + + correspond to doping levels of 1019 cm−3 [2].

Fig. 6
Fig. 6

Absorption coefficient αd plotted as a function of applied reverse bias, for two uniform indium concentrations, Nt .

Fig. 7
Fig. 7

Simulated absorption coefficient following the application of a −20 V bias, and following the removal of the bias after 10 ns.

Fig. 8
Fig. 8

Simulated αd following application of 1 V forward bias as a function of Nt = Nd (dotted line: performance of free-carrier absorption alone).

Fig. 9
Fig. 9

Turn-off time (toff) and turn-on time (ton) plotted as a function of Nt = Nd , showing the decrease in device speed concurrent with the increase in absorption.

Fig. 10
Fig. 10

Extinction ratio vs. Power (both normalized to length) for the enhanced VOA for two levels of indium doping, plotted with the performance of an undoped device operating solely by free-carrier absorption.

Tables (1)

Tables Icon

Table 1 Summary of Measured and Simulated Loss for Fabricated Waveguide Chips

Equations (4)

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

αd=σpoptx,yΦ(x,y)(Nt(x,y)nt(x,y))dxdy
TotalLoss(dB)=αdL+αiW+c
e+nt=ni2e+Nd,ntNt=cne+cpp'cn(n'+e)+cp(p'+ni2e)
αd=σpoptx,yΦ(x,y)(Nt(x,y)nt(x,y))dxdyσeoptx,yΦ(x,y)e(x,y)dxdy

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