Abstract

Both AuGe based alloys and Ti/Au metal layer stacks are widely used as ohmic metal contacts for photoconductive THz antennas made of low temperature grown GaAs. Here, we present the first systematic comparison between these two metallization types. A series of antennas of both kinds is excited by femtosecond laser pulses and by the emission from two diode lasers, i.e. we test the structures as pulsed THz emitters and as photomixers. In both cases, coherent and incoherent detection schemes are employed. We find that the power emitted from the antennas with AuGe metallization is 50% higher than that of antennas with a Ti/Au metal layer. From a comparison with a photomixer model we conclude that the higher output power results from a lower contact resistance of the AuGe contacts leading to an increased current flow. However, Ti/Au contacts have a higher thermal stability which might be advantageous if high system stability is called for.

© 2008 Optical Society of America

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    [CrossRef]

2007 (1)

S. Kasai, M. Watanabe, and T. Ouchi, "Improved Terahertz Wave Intensity in Photoconductive Antennas Formed of Annealed Low-Temperature Grown GaAs," Jpn. J. Appl. Phys. 46, 4163-4165 (2007).
[CrossRef]

2006 (1)

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

2005 (2)

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

2003 (2)

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

2002 (1)

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

2001 (1)

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

2000 (2)

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

M. Tonouchi, M. Yamashita, and M. Hangyo, "Terahertz radiation imaging of supercurrent distribution in vortex-penetrated YBa2Cu3O7-d thin film strips," J. Appl. Phys. 87, 7366-7375, (2000).
[CrossRef]

1999 (2)

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

1998 (1)

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

1997 (5)

M. Tani, S. Matsuura, K. Sakai, and S. Nakashima, "Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs," Appl. Opt. 36, 7853-7859 (1997).
[CrossRef]

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

S. Matsuura, M. Tani, and K. Sakai, "Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas," Appl. Phys. Lett. 70, 559-561 (1997).
[CrossRef]

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

1996 (3)

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

X-C. Zhang, "Generation and detection of terahertz electromagnetic pulses from semiconductor with femtosecond optics," J. Lumin. 66, 488-492 (1996).
[CrossRef]

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

1995 (1)

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

1990 (1)

H. Yamamoto, Z-Q. Fang, and D. C. Look, "Nonalloyed ohmic contacts on low-temperature molecular beam epitaxial GaAs: Influence of deep donor band," Appl. Phys. Lett,  57, 1537-1539 (1990).
[CrossRef]

1989 (1)

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

1987 (2)

G. Donzelli and A. Paccagnella, "Degradation Mechanism of Ti/Au and Ti/Pd/Au Gate Metallizations in GaAs MESFET’s," IEEE Trans. Electron Devices 34, 957-960 (1987).
[CrossRef]

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

1986 (1)

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

1980 (1)

M. Ogawa, "Alloying of Ni/Au-Ge films on GaAs," J. Appl. Phys. 51, 406-412 (1980).
[CrossRef]

1976 (1)

J. B. Gunn, "The Discovery of Microwave Oscillation in Gallium Arsenide," IEEE Trans. Electron. Devices 23, 705-713 (1976).
[CrossRef]

1975 (1)

J. D. Speight and K. Cooper, "Interlayer diffusion phenomena in Ti-Au metallization on n-type GaAs at 250°-450°C," Thin Solid Films 25, S31-S37 (1975).
[CrossRef]

1971 (1)

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

1967 (1)

N. Braslau, J. B. Gunn, and J. L. Staples, "Metal-Semiconductor Contacts For GaAs Bulk Effekt Devices," Solid-State Electron. 10, 381-383 (1967).
[CrossRef]

Adam, R.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

Baca, A. G.

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

Baker, C.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Beere, H. E.

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

Bieler, M.

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

Bradley, I. V.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Braslau, N.

N. Braslau, J. B. Gunn, and J. L. Staples, "Metal-Semiconductor Contacts For GaAs Bulk Effekt Devices," Solid-State Electron. 10, 381-383 (1967).
[CrossRef]

Brener, I.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Briggs, R. D.

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

Brown, E. R.

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

Cai, Y.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Callegari, A. C.

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

Cernea, M.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Cooper, K.

J. D. Speight and K. Cooper, "Interlayer diffusion phenomena in Ti-Au metallization on n-type GaAs at 250°-450°C," Thin Solid Films 25, S31-S37 (1975).
[CrossRef]

Davies, A. G.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

DiNatale, W. F.

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

Donzelli, G.

G. Donzelli and A. Paccagnella, "Degradation Mechanism of Ti/Au and Ti/Pd/Au Gate Metallizations in GaAs MESFET’s," IEEE Trans. Electron Devices 34, 957-960 (1987).
[CrossRef]

Duffy, S. M.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

Evans, M. J.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Fang, Z-Q.

H. Yamamoto, Z-Q. Fang, and D. C. Look, "Nonalloyed ohmic contacts on low-temperature molecular beam epitaxial GaAs: Influence of deep donor band," Appl. Phys. Lett,  57, 1537-1539 (1990).
[CrossRef]

Federici, J.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Förster, A.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

Ghita, R. V.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Gopen, H. J.

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

Gossard, A. C.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

Gregory, I. S.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Gu, P.

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

Gunn, J. B.

J. B. Gunn, "The Discovery of Microwave Oscillation in Gallium Arsenide," IEEE Trans. Electron. Devices 23, 705-713 (1976).
[CrossRef]

N. Braslau, J. B. Gunn, and J. L. Staples, "Metal-Semiconductor Contacts For GaAs Bulk Effekt Devices," Solid-State Electron. 10, 381-383 (1967).
[CrossRef]

Gyulai, J.

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

Hangyo, M.

M. Tonouchi, M. Yamashita, and M. Hangyo, "Terahertz radiation imaging of supercurrent distribution in vortex-penetrated YBa2Cu3O7-d thin film strips," J. Appl. Phys. 87, 7366-7375, (2000).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Hein, G.

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

Heisig, S.

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

Hu, Q.

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

Jackson, A.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

Kao, Y. C.

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

Kasai, S.

S. Kasai, M. Watanabe, and T. Ouchi, "Improved Terahertz Wave Intensity in Photoconductive Antennas Formed of Annealed Low-Temperature Grown GaAs," Jpn. J. Appl. Phys. 46, 4163-4165 (2007).
[CrossRef]

Keil, U. D.

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

Kendelwicz, T.

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Kono, S.

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

Kordos, P.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

Lazarescu, M. F.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Lecher, H.

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

Linfield, E. H.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

Logofatu, C.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Look, D. C.

H. Yamamoto, Z-Q. Fang, and D. C. Look, "Nonalloyed ohmic contacts on low-temperature molecular beam epitaxial GaAs: Influence of deep donor band," Appl. Phys. Lett,  57, 1537-1539 (1990).
[CrossRef]

Lopata, J.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Luo, J. K.

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

Lüth, H.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

Lyszczarz, T. M.

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

Manea, A. S.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Marso, M.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

Matsuura, S.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

S. Matsuura, M. Tani, and K. Sakai, "Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas," Appl. Phys. Lett. 70, 559-561 (1997).
[CrossRef]

M. Tani, S. Matsuura, K. Sakai, and S. Nakashima, "Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs," Appl. Opt. 36, 7853-7859 (1997).
[CrossRef]

Mayer, J. W.

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

McIntosh, K. A.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

McIntosh, K.A.

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

McMahon, O. B.

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

Mikulics, M.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

Missous, M.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Moore, T. M.

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

Morgan, D. V.

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

Murakami, M.

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

Murakami, Y.

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Nakashima, S.

M. Tani, S. Matsuura, K. Sakai, and S. Nakashima, "Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs," Appl. Opt. 36, 7853-7859 (1997).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Negrila, C.

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

Newman, N.

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Nichols, K. B.

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

Oesterschulze, E.

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

Ogawa, M.

M. Ogawa, "Alloying of Ni/Au-Ge films on GaAs," J. Appl. Phys. 51, 406-412 (1980).
[CrossRef]

Ouchi, T.

S. Kasai, M. Watanabe, and T. Ouchi, "Improved Terahertz Wave Intensity in Photoconductive Antennas Formed of Annealed Low-Temperature Grown GaAs," Jpn. J. Appl. Phys. 46, 4163-4165 (2007).
[CrossRef]

Paccagnella, A.

G. Donzelli and A. Paccagnella, "Degradation Mechanism of Ti/Au and Ti/Pd/Au Gate Metallizations in GaAs MESFET’s," IEEE Trans. Electron Devices 34, 957-960 (1987).
[CrossRef]

Pearton, S. J.

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

Pfeiffer, L.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Randall, J. N.

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

Ren, F.

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

Rodriguez, V.

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

Sakai, K.

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

M. Tani, S. Matsuura, K. Sakai, and S. Nakashima, "Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs," Appl. Opt. 36, 7853-7859 (1997).
[CrossRef]

S. Matsuura, M. Tani, and K. Sakai, "Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas," Appl. Phys. Lett. 70, 559-561 (1997).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Shen, Y. C.

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

Shih, Y-C.

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

Siegner, U.

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

Sobolewski, R.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

Speight, J. D.

J. D. Speight and K. Cooper, "Interlayer diffusion phenomena in Ti-Au metallization on n-type GaAs at 250°-450°C," Thin Solid Films 25, S31-S37 (1975).
[CrossRef]

Spicer, W. E.

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Spitzer, M.

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

Staples, J. L.

N. Braslau, J. B. Gunn, and J. L. Staples, "Metal-Semiconductor Contacts For GaAs Bulk Effekt Devices," Solid-State Electron. 10, 381-383 (1967).
[CrossRef]

Stark, J. B.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Steffens, W. M.

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

Tani, M.

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

M. Tani, S. Matsuura, K. Sakai, and S. Nakashima, "Emission characteristics of photoconductive antennas based on low-temperature-grown GaAs and semi-insulating GaAs," Appl. Opt. 36, 7853-7859 (1997).
[CrossRef]

S. Matsuura, M. Tani, and K. Sakai, "Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas," Appl. Phys. Lett. 70, 559-561 (1997).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Thomas, H.

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

Tomozawa, S.

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Tonouchi, M.

M. Tonouchi, M. Yamashita, and M. Hangyo, "Terahertz radiation imaging of supercurrent distribution in vortex-penetrated YBa2Cu3O7-d thin film strips," J. Appl. Phys. 87, 7366-7375, (2000).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Tribe, W. R.

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

Upadhya, P. C.

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

van der Hart, A.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

van Schilgaarde, M.

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Verghese, S.

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

Wang, Z.

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Watanabe, M.

S. Kasai, M. Watanabe, and T. Ouchi, "Improved Terahertz Wave Intensity in Photoconductive Antennas Formed of Annealed Low-Temperature Grown GaAs," Jpn. J. Appl. Phys. 46, 4163-4165 (2007).
[CrossRef]

Westwood, D.

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

Wilkie, E. L.

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

Williams, M. D.

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Wu, S.

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

Wynn, J.

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

Yamamoto, H.

H. Yamamoto, Z-Q. Fang, and D. C. Look, "Nonalloyed ohmic contacts on low-temperature molecular beam epitaxial GaAs: Influence of deep donor band," Appl. Phys. Lett,  57, 1537-1539 (1990).
[CrossRef]

Yamashita, M.

M. Tonouchi, M. Yamashita, and M. Hangyo, "Terahertz radiation imaging of supercurrent distribution in vortex-penetrated YBa2Cu3O7-d thin film strips," J. Appl. Phys. 87, 7366-7375, (2000).
[CrossRef]

Yang, C. H.

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

Yu, A. Y. C.

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

Zamdmer, N.

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

Zhang, X-C.

X-C. Zhang, "Generation and detection of terahertz electromagnetic pulses from semiconductor with femtosecond optics," J. Lumin. 66, 488-492 (1996).
[CrossRef]

Zheng, X.

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

Zolper, J. C.

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

Appl. Opt. (1)

Appl. Phys. B (1)

W. M. Steffens, S. Heisig, U. D. Keil, and E. Oesterschulze, "Spatio-temporal imaging of voltage pulses with a laser-gated photoconductive sampling probe," Appl. Phys. B 69, 455-458 (1999).
[CrossRef]

Appl. Phys. Lett (1)

H. Yamamoto, Z-Q. Fang, and D. C. Look, "Nonalloyed ohmic contacts on low-temperature molecular beam epitaxial GaAs: Influence of deep donor band," Appl. Phys. Lett,  57, 1537-1539 (1990).
[CrossRef]

Appl. Phys. Lett. (9)

K. A. McIntosh, E. R. Brown, K. B. Nichols, O. B. McMahon, W. F. DiNatale, and T. M. Lyszczarz, "Terahertz photomixing with diode lasers in low-temperature-grown GaAs, "Appl. Phys. Lett. 67, 3844-3846 (1995).
[CrossRef]

N. Zamdmer, Q. Hu, K.A. McIntosh, and S. Verghese, "Increase in response time of low-temperature-grown GaAs photoconductive switches at high voltage bias," Appl. Phys. Lett. 75, 2313-2315 (1999).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. B. Stark, "Coherent terahertz radiation detection: Direct comparison between free-space electro-optic sampling and antenna detection," Appl. Phys. Lett. 73, 444-446 (1998).
[CrossRef]

S. Kono, M. Tani, P. Gu, and K. Sakai, "Detection of up to 20 THz with a low-temperature-grown GaAs photoconductive antenna gated with 15 fs light pulses," Appl. Phys. Lett. 77, 4104-4106 (2000).
[CrossRef]

Y. C. Shen, P. C. Upadhya, E. H. Linfield, H. E. Beere, and A. G. Davies, "Ultrabroadband terahertz radiation from low-temperature-grown GaAs photoconductive emitters," Appl. Phys. Lett. 83, 3117-3119 (2003).
[CrossRef]

K. A. McIntosh, K. B. Nichols, S. Verghese, and E. R. Brown, "Investigation of ultrashort photocarrier relaxation times in low-temperature-grown GaAs," Appl. Phys. Lett. 70, 354-356 (1997).
[CrossRef]

Y. Cai, I. Brener, J. Lopata, J. Wynn, L. Pfeiffer, and J. Federici, "Design and performance of singular electric field terahertz photoconducting antennas," Appl. Phys. Lett. 71, 2076-2078 (1997).
[CrossRef]

S. Matsuura, M. Tani, and K. Sakai, "Generation of coherent terahertz radiation by photomixing in dipole photoconductive antennas," Appl. Phys. Lett. 70, 559-561 (1997).
[CrossRef]

M. Hangyo, S. Tomozawa, Y. Murakami, M. Tonouchi, M. Tani, Z. Wang, K. Sakai, and S. Nakashima, "Terahertz radiation from superconducting YBa2Cu3O7-d thin films excited by femtosecond optical pulses," Appl. Phys. Lett. 69, 2122-2124, (1996).
[CrossRef]

Electron. Lett. (1)

M. Bieler, M. Spitzer, H. Lecher, G. Hein, and U. Siegner, "Transfer of sub-5 ps electrical test pulses to coplanar and coaxial electronic devices," Electron. Lett. 38, 125-126 (2002).
[CrossRef]

IEEE J. Quantum Electron. (1)

I. S. Gregory, C. Baker, W. R. Tribe, I. V. Bradley, M. J. Evans, E. H. Linfield, A. G. Davies, and M. Missous, "Optimization of Photomixers and Antennas for Continuous-Wave Terahertz Emission," IEEE J. Quantum Electron. 41, 717-728 (2005).
[CrossRef]

IEEE Photon. Techn. Lett. (1)

M. Mikulics, X. Zheng, R. Adam, R. Sobolewski, and P. Kordos, "High-Speed Photoconductive Switch Based on Low-Temperature GaAs Transferred on SiO2-Si Substrate," IEEE Photon. Techn. Lett. 15, 528-530 (2003).
[CrossRef]

IEEE Photon. Technol. Lett. (1)

M. Mikulics, S. Wu, M. Marso, R. Adam, A. Förster, A. van der Hart, P. Kordos, H. Lüth, and R. Sobolewski, "Ultrafast and Highly Sensitive Photodetectors with Recessed Electrodes Fabricated on Low-Temperature-Grown GaAs," IEEE Photon. Technol. Lett. 18, 820-822 (2006).
[CrossRef]

IEEE Trans. Electron Devices (1)

G. Donzelli and A. Paccagnella, "Degradation Mechanism of Ti/Au and Ti/Pd/Au Gate Metallizations in GaAs MESFET’s," IEEE Trans. Electron Devices 34, 957-960 (1987).
[CrossRef]

IEEE Trans. Electron. Devices (1)

J. B. Gunn, "The Discovery of Microwave Oscillation in Gallium Arsenide," IEEE Trans. Electron. Devices 23, 705-713 (1976).
[CrossRef]

IEEE Trans. Microwave Theory Tech. (1)

S. M. Duffy, S. Verghese, K. A. McIntosh, A. Jackson, A. C. Gossard, and S. Matsuura, "Accurate Modeling of Dual Dipole and Slot Elements Used with Photomixers for Coherent Terahertz Output Power," IEEE Trans. Microwave Theory Tech. 49, 1032-1038 (2001).
[CrossRef]

J. Appl. Phys. (5)

M. Tonouchi, M. Yamashita, and M. Hangyo, "Terahertz radiation imaging of supercurrent distribution in vortex-penetrated YBa2Cu3O7-d thin film strips," J. Appl. Phys. 87, 7366-7375, (2000).
[CrossRef]

J. K. Luo, H. Thomas, D. V. Morgan, and D. Westwood, "Transport properties of GaAs layers grown by molecular beam epitaxy at low temperature and the effects of annealing," J. Appl. Phys. 79, 3622-3629 (1996).
[CrossRef]

J. Gyulai, J. W. Mayer, V. Rodriguez, A. Y. C. Yu, and H. J. Gopen, "Alloying Behavior of Au and Au-Ge on GaAs," J. Appl. Phys. 42, 3578-3585, (1971).
[CrossRef]

Y-C. Shih, M. Murakami, E. L. Wilkie, and A. C. Callegari, "Effects of interfacial microstructure on uniformity and thermal stability of AuNiGe ohmic contact to n-type GaAs," J. Appl. Phys. 62, 582-590, (1987).
[CrossRef]

M. Ogawa, "Alloying of Ni/Au-Ge films on GaAs," J. Appl. Phys. 51, 406-412 (1980).
[CrossRef]

J. Lumin. (1)

X-C. Zhang, "Generation and detection of terahertz electromagnetic pulses from semiconductor with femtosecond optics," J. Lumin. 66, 488-492 (1996).
[CrossRef]

J. Optoelectron. Adv. Mater. (1)

R. V. Ghita, C. Logofatu, C. Negrila, A. S. Manea, M. Cernea, and M. F. Lazarescu, "Studies of Ohmic Contact and Schottky Barriers on Au-Ge/GaAs and Au-Ti/GaAs," J. Optoelectron. Adv. Mater. 7, 3033-3037 (2005).

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

J. N. Randall, C. H. Yang, Y. C. Kao, and T. M. Moore, "Fabrication of electron beam defined ultrasmall Ohmic contacts for III-V semiconductors," J. Vac. Sci. Technol. B 7, 2007-2010 (1989).
[CrossRef]

Jpn. J. Appl. Phys. (1)

S. Kasai, M. Watanabe, and T. Ouchi, "Improved Terahertz Wave Intensity in Photoconductive Antennas Formed of Annealed Low-Temperature Grown GaAs," Jpn. J. Appl. Phys. 46, 4163-4165 (2007).
[CrossRef]

Phys. Rev. B (1)

N. Newman, M. van Schilgaarde, T. Kendelwicz, M. D. Williams, and W. E. Spicer, "Electrical study of Schottky barriers on atomically clean GaAs(110) surfaces," Phys. Rev. B 33, 1146-1159 (1986).
[CrossRef]

Solid-State Electron. (1)

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[CrossRef]

Thin Solid Films (2)

A. G. Baca, F. Ren, J. C. Zolper, R. D. Briggs, and S. J. Pearton, "A survey of ohmic contacts to III-V compound semiconductors," Thin Solid Films 308-309, 599-606 (1997).
[CrossRef]

J. D. Speight and K. Cooper, "Interlayer diffusion phenomena in Ti-Au metallization on n-type GaAs at 250°-450°C," Thin Solid Films 25, S31-S37 (1975).
[CrossRef]

Other (8)

H. Kuchling, Taschenbuch der Physik (Fachbuchverlag Leipzig, 2001).

A. Krotkus, K. Bertulis, and R. Adomavicius, "Low temperature MBE grown GaAs for terahertz radiation application," Proc. 12th GAAS Symposium-Amsterdam (2004).

E. D. Marshall and M. Murakami, "in Contacts to semiconductor," L. J. Brillson, ed., (Noyes Publication, New Jersey, 1993).

M. Mikulics, E. A. Michael, R. Schieder, J. Stutzki, R. Güsten, M. Marso, A. van der Hart, H. P. Bochem, H. Lüth, and P. Kordoš, "Traveling-wave photomixer with recessed interdigitated contacts on low-temperature-grown GaAs," Appl. Phys. Lett.  88, 41118-1 - 41118-3, (2006).
[CrossRef]

M. Mikulics, "Preparation and Optimization of Low-Temperature-Grown GaAs Photomixers," PhD thesis, RWTH Aachen and FZ Jülich, (2005).

M. Mikulics, M. Marso, I. Cámara Mayorga, R. Güsten, S. Stanček, P. Kováč, S. Wu, X. Li, M. Khafizov, R. Sobolewski, E. A. Michael, R. Schieder, M. Wolter, D. Buca, A. Förster, P. Kordoš, and H. Lüth, "Photomixers fabricated on nitrogen-ion-implanted GaAs," Appl. Phys. Lett. 87, 41106-1 - 41106-3, (2005).
[CrossRef]

K. Sakai, ed., Terahertz Optoelectronics (Springer, Berlin, 2005).
[CrossRef]

M. Griebel, Ultraschnelle Ladungsträgerdynamik in LTG-GaAs und ErAs:GaAs-Übergittern-Grundlagen und Anwendungen, PhD thesis, MPI, Stuttgart, (2002).

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Figures (10)

Fig. 1.
Fig. 1.

(a) Coherent detection setup: a second photoconductive antenna is used as detector. The excitation is performed either with the emission of two diode lasers or with femtosecond laser pulses. b) Incoherent detection scheme: a Golay cell is used as detector.

Fig. 2.
Fig. 2.

FIT simulation (CST microwave studio) of the antenna impedance RL

Fig. 3.
Fig. 3.

Equivalent electronic circuit diagram of the photomixer

Fig. 4.
Fig. 4.

Simulated spectral distribution of the power radiated by the photomixer.

Fig. 5.
Fig. 5.

Measured spectral distribution of the power radiated by the photomixer.

Fig. 6.
Fig. 6.

Output power of the antennas versus the bias electric field measured with the Golay cell.

Fig. 7.
Fig. 7.

Electric field radiated by the photomixer obtained via coherent detection.

Fig. 8.
Fig. 8.

Output power of the coplanar striplines under femtosecond illumination. The power is measured with the Golay cell.

Fig. 9.
Fig. 9.

THz waveforms obtained in a THz time-domain spectrometer. A second photoconductive antenna serves as detector.

Fig. 10.
Fig. 10.

Spectra of the THz waveforms presented in Fig. 9.

Equations (7)

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

G 0 = ( μ e + μ h ) T opt η P ̅ opt e τ h v A ,
G eff = G 0 1 + G 0 R S .
R S = R tot R S G 0 + 1 G 0 + j ω C · ( 1 + R s G 0 ) .
R S = R tot G 0 1 R L .
P ω = 1 2 ( V B G 0 ) 2 R L ( 1 + ω 2 τ 2 ) ( 1 + ω 2 R L 2 C 2 ) 1 ( 1 + G 0 R S ) 2 .
P AuGe P Ti Au = ( 1 + Rs Ti Au G 0 1 + Rs AuGe G 0 ) 2 .
P AuGe P Ti Au = Rs Ti Au Rs AuGe = 2.35 ,

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