DOI QR코드

DOI QR Code

A Study of Be Levels in p-GaSb:Be/GaAs Epitaxial Layers

p-GaSb:Be/GaAs 에피층의 Be 준위에 관한 연구

  • Noh, S.K. (Global Research Laboratory on Quantum Detector Technology, Korea Research Institute of Standards and Science) ;
  • Kim, J.O. (Global Research Laboratory on Quantum Detector Technology, Korea Research Institute of Standards and Science) ;
  • Lee, S.J. (Global Research Laboratory on Quantum Detector Technology, Korea Research Institute of Standards and Science)
  • 노삼규 (한국표준과학연구원 나노소재평가센터 양자검출소자 글로벌연구실) ;
  • 김준오 (한국표준과학연구원 나노소재평가센터 양자검출소자 글로벌연구실) ;
  • 이상준 (한국표준과학연구원 나노소재평가센터 양자검출소자 글로벌연구실)
  • Received : 2010.10.25
  • Accepted : 2011.03.09
  • Published : 2011.03.30

Abstract

By investigating photoluminescence (PL) spectra (20 K) of undoped and Be-doped p-type GaSb/GaAs epilayers, the origin has been analyzed by the change due to doping density. We have observed that the PL peak shifts to higher energy and the full-width half-maximum (FWHM) decreases with increasing the doping density below ${\sim}10^{17}cm^{-3}$, contrasted to shift to low energy and increasing FWHM above the density of ${\sim}10^{17}cm^{-3}$. From the variation of the integrated PL intensities of three peaks dissolved by Gaussian fit, it has been analyzed that, as the density increases, the $Be[Be_{Ga}]$ acceptor level (0.794 eV) reduces, whereas the intrinsic defect of $A[Ga_{Sb}]$ (0.778 eV) enhances together with a new $Be^*$ level (0.787 eV) locating between A and Be. We have discussed that it is due to coexistence of the Be acceptor level (${\Delta}E=16meV$) and the complex level (${\Delta}E=23meV$), $Be^*[Ga_{Sb}-Be_{Ga}]$combined by Be and A, in Be-doped p-GaSb, and that the level density of $Be[Be_{Ga}]$ may be reduced above ${\sim}10^{17}cm^{-3}$.

Be을 도핑한 p형 GaSb:Be 에피층의 광여기 발광(PL) 스펙트럼(20 K)의 도핑밀도에 따른 변화를 조사하여, Be 억셉터의 근원을 분석하였다. 도핑을 증가시키면 PL 피크가 고에너지로 변위하고 반치폭은 줄어드는 경향을 보이다가, 밀도가 ${\sim}10^{17}cm^{-3}$ 이상에서 피크 에너지는 오히려 저에너지로 변위하고 반치폭이 늘어나는 현상을 관측하였다. 3개 피크로 분리한 PL 스펙트럼의 적분 PL 강도 변화를 통하여, 도핑 증가에 따라 $Be[Be_{Ga}]$ 준위(0.794 eV)는 감소하는 반면 진성결함에 기인한 $A[Ga_{Sb}]$ 피크(0.778 eV)와 함께 Be과 A 사이에 위치하는 새로운 $Be^*$ 준위(0.787 eV)가 증가하기 때문으로 분석되었다. 이것은 Be을 도핑한 p-GaSb:Be 에피층에는 Be 얕은준위(${\Delta}E=16meV$)와 Be과 A 결함준위가 결합한 $Be^*[Ga_{Sb}-Be_{Ga}]$의 복합준위(${\Delta}E=23meV$)가 공존하기 때문으로 논의하였으며, ${\sim}10^{17}cm^{-3}$ 이상 도핑할 경우에는 Be 준위가 다소 감소할 수 있음을 보였다.

Keywords

References

  1. D. L. Smith and C. Mailhiot, J. Appl. Phys. 62, 2545 (1987). https://doi.org/10.1063/1.339468
  2. P. S. Dutta and H. L. Bhat, J. Appl. Phys. 81, 5821 (1997). https://doi.org/10.1063/1.365356
  3. H. S. Kim, E. Plis, A. Khoshakhlagh, S. Myers, N. Gautam, Y. D. Sharma, L. R. Dawson, S. Krishna, S. J. Lee, and S. K. Noh, Appl. Phys. Lett. 96, 033502 (2010). https://doi.org/10.1063/1.3275711
  4. S. J. Lee, S. K. Noh, L. R. Dawson, and S. Krishna, J. Korean Phys. Soc. 54, 280 (2009). https://doi.org/10.3938/jkps.54.280
  5. J. O. Kim, H. W. Shin, J. W. Choe, S. J. Lee, C. S. Kim, and S. K. Noh, J. Korean Vacuum Soc. 18, 245 (2009). https://doi.org/10.5757/JKVS.2009.18.4.245
  6. B. Movaghar, S. Tsao, S. A. Pour, S. A. Pour, T. Yamanaka, and M. Razeghi, Phys. Rev. B 78, 115320 (2008). https://doi.org/10.1103/PhysRevB.78.115320
  7. G. C. Dente and M. L. Tilton, J. Appl. Phys. 86, 1420 (1999). https://doi.org/10.1063/1.370905
  8. E. Plis, J. B. Rodriguez, H. S. Kim, G. Bishop, Y. Sharma, R. Dawson, S. J. Lee, C. E. Jones, V. Gopal, and S. Krishna, Appl. Phys. Lett. 91, 133512 (2007). https://doi.org/10.1063/1.2790078
  9. S. J. Lee, S. K. Noh, E. Plis, S. Krishna, and K.-S. Lee, Appl. Phys. Lett. 95, 102106 (2009). https://doi.org/10.1063/1.3212738
  10. S. J. Lee, S. K. Noh, S. H. Bae, and H. Jung, J. Korean Vacuum Soc. 20, 22 (2011). https://doi.org/10.5757/JKVS.2011.20.1.022
  11. S. Maison and G. W. Wicks, Appl. Phys. Lett. 89, 151109 (2006). https://doi.org/10.1063/1.2360235
  12. A. Chroneos and H. Bracht, J. Appl. Phys. 104, 093714 (2008). https://doi.org/10.1063/1.3010300
  13. M. Hakala, M. J. Puska, and R. M. Nieminen, J. Appl. Phys. 91, 4988 (2002). https://doi.org/10.1063/1.1462844
  14. R. Hao, Y. Xu, Z. Zhou, Z. Ren, H. Ni, Z. He, and Z. Niu, J. Phys. D: Appl. Phys. 40, 1080 (2007). https://doi.org/10.1088/0022-3727/40/4/025
  15. M. -C. Wu and C. -C. Chen, J. Appl. Phys. 72, 4275 (1992). https://doi.org/10.1063/1.352216
  16. L. T. -Mejia, J. A. Villada, M. de los Rios, J. A. Penafiel, G. Fonthal, D. G. E. -Arbelaez, H. A. -Calderon, and M. E. R. -Garcia, Physica B 403, 4027 (2008). https://doi.org/10.1016/j.physb.2008.07.049
  17. W. G. Hu, Z. Wang, B. F. Su, Y. Q. Dai, S. J. Wang, and Y. W. Zhao, Phys. Lett. A 332, 286 (2004). https://doi.org/10.1016/j.physleta.2004.09.056
  18. J. O. Kim, H. W. Shin, J. W. Choe, S. J. Lee, and S. K. Noh, J. Korean Vacuum Soc. 18, 127 (2009). https://doi.org/10.5757/JKVS.2009.18.2.127

Cited by

  1. Electronic Structure of GaxIn1-xSbyAs1-y: Band Alignments Based on UTB Calculations vol.20, pp.6, 2011, https://doi.org/10.5757/JKVS.2011.20.6.461