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A Study of Traps in Semi-Insulating III-V Epitaxial Films by Zero Bias Transient Current Spectroscopy

Published online by Cambridge University Press:  22 February 2011

W. S. Lau
Affiliation:
Centre for Optoelectronics, Faculty of Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511
C. H. Goo
Affiliation:
Centre for Optoelectronics, Faculty of Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511
T. C. Chong
Affiliation:
Centre for Optoelectronics, Faculty of Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511
C. T. Tan
Affiliation:
Centre for Optoelectronics, Faculty of Engineering, National University of Singapore, 10 Kent Ridge Crescent, Singapore 0511
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Abstract

Semi-insulating Al0.3Ga0.7AS epitaxial films grown by molecular beam epitaxy at 400°C have been characterised by a recently proposed technique known as zero quiescent bias voltage transient current spectroscopy (ZBTCS). Separated electron trap spectra and hole trap spectra are obtained by ZBTCS. From these spectra, a prominent hole trap with an activation energy of 1.01eV, a prominent electron trap with an activation energy of 0.86eV and a continuum of states are detected. The trap concentrations of the detected hole trap and electron trap are calculated to be about 3.6x1015cm−3 and 9.7x1015cm−3 respectively. The continuum of states is believed to be due to the surface states of the Al0.3Ga0.7AS film. By passivating the surface with (NH4)2S solution, the magnitudes of the continuums in the spectra reduce significantly. With the reduction of the surface states, hole injections that interfere the electron trap spectra are suppressed, and consequently electron trap spectra with more pronounced peaks are produced.

Type
Research Article
Copyright
Copyright © Materials Research Society 1994

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References

REFERENCES

1. Chen, C.L., Smith, F.W., Clifton, B.J., Mahoney, L.J., Manfra, M.J. and Calawa, A.R., IEEE Electron Device Lett. EDL–12, 306 (1991).Google Scholar
2. Smith, F.W., Calawa, A.R., Chen, C.L., Manfra, M.J. and Mahoney, L.J., IEEE Electron Device Lett. EDL–9, 77 (1988).Google Scholar
3. Lau, W.S., Chong, T.C., Tan, L.S., Goo, C.H. and Goh, K.S., Jpn. J. Appl. Phys. 30, L1843 (1991).Google Scholar
4. Lau, W.S., Chong, T.C., Tan, L.S., Goo, C.H., Goh, K.S. and Lee, K.M., Appl. Phys. Lett. 61, 1, 49 (1992).Google Scholar
5. Desnica, D.I., J. Electron. Mater. 21, 4, 463 (1992).Google Scholar
6. Lau, W.S., Goo, C.H. and Chong, T.C., Proc. 7th International Conference on Semiinsulating III-IV Materials, Ixtapa, 153 (1992).Google Scholar
7. Lau, W.S., Goo, C.H., Chong, T.C. and Chu, P.K., Jpn. J. Appl. Phys., 32, L1192 (1993).Google Scholar
8. Wager, J.F. and McCamant, A.J., IEEE Trans. Electron Devices 34 1001 (1987).Google Scholar
9. Nannichi, Y., Fan, J.F., Oigawa, H. and Koma, A., Jpn. J. Appl. Phys., 27, L2367 (1988).Google Scholar
10. Kawanishi, H., Ohno, H., Morimoto, T., Kaneiwa, S., Miyauchi, N., Hayashi, H., Akagi, Y., Nakajima, Y. and Hijikata, T., Proc. the 21st Conf. Solid State Devices and Materials, 337 (1989).Google Scholar