Hostname: page-component-745bb68f8f-b6zl4 Total loading time: 0 Render date: 2025-02-09T22:17:59.266Z Has data issue: false hasContentIssue false
  • English
  • Français

Piezoelectric Quantization in GaInN thin Films and Multiple Quantum Well Structures

Published online by Cambridge University Press:  10 February 2011

Christian Wetzel ,
Tetsuya Takeuchi ,
Hiroshi Amano  and
Isamu Akasaki
Christian Wetzel
Affiliation:
High Tech Research Center and Department of Electrical and Electronic Engineering, Meijo University, 1–501 Shiogamaguchi, Tempaku-ku, Nagoya 468–8502, Japan.
Tetsuya Takeuchi
Affiliation:
High Tech Research Center and Department of Electrical and Electronic Engineering, Meijo University, 1–501 Shiogamaguchi, Tempaku-ku, Nagoya 468–8502, Japan.
Hiroshi Amano
Affiliation:
High Tech Research Center and Department of Electrical and Electronic Engineering, Meijo University, 1–501 Shiogamaguchi, Tempaku-ku, Nagoya 468–8502, Japan.
Isamu Akasaki
Affiliation:
High Tech Research Center and Department of Electrical and Electronic Engineering, Meijo University, 1–501 Shiogamaguchi, Tempaku-ku, Nagoya 468–8502, Japan.
Get access

Abstract

Details of the electronic bandstructure in pseudomorphic Gal-xInxN/GaN single heterostructures (0 < x < 0.22) are studied. In photocarrier modulated reflectance strong modulation of the density of states (Franz-Keldysh oscillations) is found due to a piezoelectric field of about 0.6 MV/cm in the strained layer. No excitons are expected to form in the presence of this field. Studying the composition dependence we determine a piezoelectric coefficient ∂|P|/∂εzz = 0.46 C/m2 and extrapolate a spontaneous polarization in GaN |Peq| = 3.9 mC/m2. Photoreflection indicates the presence of localized tail states 50 – 100 meV below the bandgap which are well explained by the Franz-Keldysh effect involving k non-conserving transitions in the large electric field. Luminescence is found to originate in these electric field induced states. The derived bandgap energies can be approximated by an interpolation yielding bowing parameters b = 2.6 eV (photoreflection) and b = 3.2 eV (luminescence) for pseudomorphic films with 0.07 ≤ x ≤ 0. 22. These findings may affect interpretation of device performance.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 512: Symposium F – Wide Bandgap Semiconductors for High Power, High Frequency , 1998 , 181
Copyright
Copyright © Materials Research Society 1998

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

REFERENCES

1. Amano, H., Sawaki, N., Akasaki, I., and Toyoda, Y., Appl. Phys. Lett. 48, 353 (1986).Google Scholar
2. Akasaki, I., Amano, H., Koide, Y., Hiramatsu, K., and Sawaki, N., J. Cryst. Growth 98, 209 (1989).Google Scholar
3. Akasaki, I., Sawaki, N., Hiramatsu, K., and Goto, H.. Report of Priority Area Research Program, supp. by Ministry of Edu. Sci. Culture of Jap (in japanese) (1988) p. 106 ff.Google Scholar
4. Yu, E.T., Sullivan, G.J., Asbeck, P.M., Wang, C.D., Qiao, D., Lau, S.S., Appl. Phys. Lett. 71, 2794 (1997).Google Scholar
5. Takeuchi, T., Sota, S., Katsuragawa, M., Komori, M., Takeuchi, H., Amano, H., and Akasaki, I., Jpn. J. Appl. Phys. 36, L 382 (1997).Google Scholar
6. Amano, H., Takeuchi, T., Sota, S., Sakai, H., and Akasaki, I. (Eds. Ponce, F., Moustakas, T.D., Akasaki, I., and Monemar, B.), Mater. Res. Soc. 449, (1997) p. 1143.Google Scholar
7. Wetzel, C., Takeuchi, T., Amano, H., and Akasaki, I., J. Cryst. Growth (1998). in printGoogle Scholar
8. Wetzel, C., Amano, H., Akasaki, I., Suski, T., Ager, J.W., Weber, E.R., Haller, E.E., and Meyer, B.K., Nitride Semiconductors, Eds. DenBaars, S.P., Meyer, B.K., Nakamura, S., Ponce, F.A., Strite, T., Mater. Res. Soc. 482 (1998). in printGoogle Scholar
9. Aspnes, D.E. Phys. Rev. 153, 972 (1967).Google Scholar
10. Aspnes, D.E. and Studna, A.A. Phy. Rev. B7, 4605 (1973).Google Scholar
11. Böer, K.W. Survey of Semiconductor physics Van Nostrand Reinhold, New York (1990) p. 968.Google Scholar
12. Bernardini, F., Fiorentini, V., and Vanderbilt, D., Phys. Rev. Lett. 79, 3958 (1997).Google Scholar