Strategies For Direct Monolithic Integration of AlxGa(1−x)As/InxGa(1−x)As LEDS and Lasers On Ge/GeSi/Si Substrates Via Relaxed Graded GexSi(1−x) Buffer Layers


AlxGa(1−x)As/GaAs quantum well lasers have been demonstrated via organometallic chemical vapor deposition (OMCVD) on relaxed graded GexSi(1−x) virtual substrates on Si. Despite unoptimized laser structures with high series resistance and large threshold current densities, surface threading dislocation densities as low as 2×106 cm−2 enabled cw room-temperature lasing at a wavelength of 858nm. The laser structures are oxide-stripe gain-guided devices with differential quantum efficiencies of 0.16 and threshold current densities of 1550A/cm2. Identical devices grown on commercial GaAs substrates showed differential quantum efficiencies of 0.14 and threshold current densities of 1700A/cm2. This comparative data agrees with our previous measurements of near-bulk minority carrier lifetimes in GaAs grown on Ge/GeSi/Si substrates. A number of GaAs/Ge/Si integration issues including thermal expansion mismatch and Ge autodoping behavior in GaAs were overcome.

This is a preview of subscription content, access via your institution.


  1. 1

    H. Kroemer, T.Y. Liu, and M. Petroff, Journal of Crystal Growth 95, 96 (1989).

    CAS  Article  Google Scholar 

  2. 2

    Z. Hatzopoulos, D. Cengher, G. Deligeorgis, M. Androulidaki, E. Aperathitis, G. Halkias, A. Georgakilas, Journal of Crystal Growth 227–228, 193 (2001).

    Article  Google Scholar 

  3. 3

    Z.I. Kazi, P. Thilakan, T. Egawa, M. Umeno, and T. Jimbo, Japanese Journal of Applied Physics 40 (8), 4903 (2001).

    CAS  Article  Google Scholar 

  4. 4

    P.J. Taylor, W.A. Jesser, J.D. Benson, M. Martinka, J.H. Dinan, J. Bradshaw, M. Lara-Taysing, R.P. Leavitt, G. Simonis, W. Chang, W.W. Clark, and K.A. Bertness, Journal of Applied Physics 89 (8), 4365 (2001).

    CAS  Article  Google Scholar 

  5. 5

    M. T. Currie, S. B. Samavedam, T. A. Langdo, C. W. Leitz, and E. A. Fitzgerald, Applied Physics Letters 72 (14), 1718 (1998).

    CAS  Article  Google Scholar 

  6. 6

    S. Ting, M. Bulsara, V. Yang, M. Groenert, S. Samavedam, M. Currie, T. Langdo, E. Fitzgerald, A. Joshi, R. Brown, X. Wang, R. Sieg, S. Ringel, presented at the SPIE Conference on Optoelectronics, San Jose, CA, 1999 (unpublished).

    Google Scholar 

  7. 7

    S.A. Ringel, J.A. Carlin, C.W. Leitz, M. Currie, T. Langdo, E.A. Fitzgerald, M. Bulsara, D.M. Wilt, and E.V. Clark, presented at the 16th European Photovoltaics Solar Energy Conference and Exhibition, Glasgow, Scotland, 2000 (unpublished).

    Google Scholar 

  8. 8

    G.R. Srinivasan, Journal of the Electrochemical Society 127 (6), 1334 (1980).

    CAS  Article  Google Scholar 

  9. 9

    J.O. Carlsson, M. Boman, presented at the 9th International Conference on Chemical Vapor Deposition, Cincinnati, OH, 1984 (unpublished).

    Google Scholar 

  10. 10

    H. Kasano, Solid State Electronics 16, 913 (1973).

    CAS  Article  Google Scholar 

  11. 11

    S. H. Yellen, A.H. Shepard, R.J. Dalby, J.A. Baumann, H.B. Serreze, T.S. Guido, R. Soltz, K.J. Bystrom, C.M. Harding, and R.G. Waters, IEEE Journal of Quantum Electronics 29 (6), 2058 (1993).

    CAS  Article  Google Scholar 

Download references

Author information



Corresponding author

Correspondence to Michael E. Groenert.

Rights and permissions

Reprints and Permissions

About this article

Cite this article

Groenert, M.E., Leitz, C.W., Pitera, A.J. et al. Strategies For Direct Monolithic Integration of AlxGa(1−x)As/InxGa(1−x)As LEDS and Lasers On Ge/GeSi/Si Substrates Via Relaxed Graded GexSi(1−x) Buffer Layers. MRS Online Proceedings Library 692, 9301 (2001).

Download citation