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Space Charge Analysis in Thin SiO2 Films: Local Vs. Uniform Degradation Models

Published online by Cambridge University Press:  10 February 2011

A. E. Kotov*
Affiliation:
NOVA Co., 19, Panasa Mimogo Str., Kiev 252011, Ukraine, [email protected]
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Abstract

The behavior of small MOS structures (area 3 μm2), subjected to stresses caused by electron injection, demonstrates an obvious non-parallel shift in the tunneling characteristics (NPS effect), measured in the wide current range (3·10-16 -3·10-8 A) from either tunneling interface. This paper describes and compares two different approaches for the NPS effect interpretation: uniform and local degradation models (UDM and LDM). The UDM implies a modification of the oxide tunneling barrier due to area-uniform electron trapping inside the tunneling distance which could lead to the NPS effect [14]. It is shown that any spatial distribution of negative oxide charge is inapplicable to interpret the NPS effect within the framework of the UDM. The second approach uses the assumption of small (area ∼ 10-3 μm2) structure-stable regions (SSR) formed in noncrystalline SiO2 films during thermal growth. Due to the high resistance of SSRs to the degradation - negative charge generation - electron injection is gradually localized in the SSRs, avoiding a screening effect of electron trapping. It is shown that the influence of non-uniformity in the electron injection appears to be more significant, when degraded MOS structure is tested at low voltages (NPS effect).

Type
Research Article
Copyright
Copyright © Materials Research Society 1997

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References

REFERENCES

1. Harari, E., J. Appl. Phys. 49, 478 (1978).Google Scholar
2. Avni, E. and Shapir, J., J. Appl. Phys. 64 (2), 743 (1988).Google Scholar
3. Suná, J. et al., Microelectron. Journal 20 (6), 27 (1989).Google Scholar
4. Degraeve, R. et al., Microel. Eng. 28, 313 (1995).Google Scholar
5. Blaise, G., J. Appl. Phys. 77 (7), 2916 (1995); IEEE Trans, on El. Insul. 28 (4), 417 (1993).Google Scholar
6. Sofield, C.J. and Stoneham, A.M., Semicond. Sci. Technol. 10, 215 (1995).Google Scholar
7. Litovchenko, V.G. and Gorban, A.P., Physics of MOS-structures (Kiev, Naukova Dumka, 1978), Chaps. 3,4 (in Russian).Google Scholar
8. Rumak, N.V. and Khatko, V.V., Dielectric films in microelectronics (Minsk, Nauka i Tekhnika, 1990), Chaps. 2,3 (in Russian).Google Scholar
9. Revesz, A.G. and Huges, H.L., J. of Non-Cryst. Sol. 71, 89 (1985).Google Scholar
Kotov, O. A., in Materials Reliability in Microelectronics V, MRS Proc. 391, p. 27 (1995).Google Scholar
11. Kotov, A., in Proc. of IEEE NonVol. Memory Conf, Albuquerque, June 24–26, p. 105 (1996).Google Scholar
12. Olivo, P. et al., Appl. Phys. Lett. 48 (17), 1135 (1986).Google Scholar
13. Elhari, S. et. al., J. Appl. Phys. 76 (2), 1013 (1994).Google Scholar
14. Oh, S.J. and Yeow, Y.T., Sol. St. Electronics 32, No. 6, p. 507 (1989).Google Scholar
15. Nissan-Cohen, Y. et al., J. Appl. Phys. 60 (6), 2024 (1986).Google Scholar
16. DiMaria, D.J. and Stasiak, J.W., J. Appl. Phys. 65 (6), 2342 (1989).Google Scholar
17. DiMaria, D.J. and Stathis, J.H., J. Appl. Phys. 70 (3), 1500 (1991).Google Scholar
18. Chen, C-F. and Wu, C.-Y., Solid-St. Electron., 29 (10), 1059 (1986).Google Scholar
19. DiMaria, D.J., J. Appl. Phys. 47, 4073 (1976).Google Scholar