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Spectrum of Defect States in Porous Organic Low-k Dielectric Films, Annealed in Argon and Nitrogen

Published online by Cambridge University Press:  01 February 2011

V. Ligatchev
Affiliation:
Division of Microelectronics, School of Electrical and Electronic Engineering, NanyangTechnological University, Nanyang Avenue, Singapore 639798;
T.K.S. Wong
Affiliation:
Division of Microelectronics, School of Electrical and Electronic Engineering, NanyangTechnological University, Nanyang Avenue, Singapore 639798;
T.K. Goh
Affiliation:
Division of Microelectronics, School of Electrical and Electronic Engineering, NanyangTechnological University, Nanyang Avenue, Singapore 639798;
Rusli Suzhu Yu
Affiliation:
Division of Microelectronics, School of Electrical and Electronic Engineering, NanyangTechnological University, Nanyang Avenue, Singapore 639798;
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Abstract

Defect spectrum N(E) of porous organic dielectric (POD) films is studied with capacitance deep-level-transient-spectroscopy (C-DLTS) in the energy range up to 0.7 eV below conduction band bottom Ec. The POD films were prepared by spin coating onto 200mm p-type (1 – 10 Δcm) single-side polished silicon substrates followed by baking at 325°C on a hot plate and curing at 425°C in furnace. The film thickness is in the 5000 – 6000 Å range. The ‘sandwich’ -type NiCr/POD/p-Si/NiCr test structures showed both rectifying DC current-voltage characteristics and linear 1/C2 vs. DC reverse bias voltage. These confirm the applicability of the C-DLTS technique for defect spectrum deconvolution and the n-type conductivity of the studied films. Isochronal annealing (30 min in argon or 60 min in nitrogen) has been performed over the temperature range 300°C - 650°C. The N(E) distribution is only slightly affected by annealing in argon. However, the distribution depends strongly on the annealing temperature in nitrogen ambient. A strong N(E) peak at Ec – E = 0.55 – 0.60 eV is detected in all samples annealed in argon but this peak is practically absent in samples annealed in nitrogen at Ta < 480°C. On the other hand, two new peaks at Ec – E = 0.12 and 0.20 eV appear in the N(E) spectrum of the samples annealed in nitrogen at Ta = 650°C. The different features of the defect spectrum are attributed to different interactions of argon and nitrogen with dangling carbon bonds on the intra-pore surfaces.

Type
Research Article
Copyright
Copyright © Materials Research Society 2003

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References

1. Ting, C.H., Seidel, T.E., Mat. Res. Soc. Symp. Proc., 381, 3 (1995).Google Scholar
2. Ferrary, A.C., Libassi, A., Tanner, B.K. et al. Phys. Rev. B, 62, 11089 (2000).Google Scholar
3. Martin, S. J., Godschalx, J. P., Mills, M. E., Shaffer, E. O. II and Townsend, P. H., Adv. Mater., 12, 1769 (2000).Google Scholar
4. Socrates, G., Infrared and Raman characteristic group frequencies: tables and charts. Chichester, New York: Wiley, 2001.Google Scholar
5. Baxter, R. J., Aust. J. Phys., 21, 563 (1968).Google Scholar
6. Lang, D.V., J. Appl. Phys. 45 3023 (1974).Google Scholar
7. Weiss, S. and Kassing, R., Sol. St. Electronics, 31 1733 (1988).Google Scholar