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Infrared absorption and annealing behavior of semi-insulating 4H SiC HTCVD substrates

Published online by Cambridge University Press:  21 March 2011

B. Magnusson
Affiliation:
Department of Physics and Measurement Technology, Linköping University, SE-581 83 Linköping, Sweden
A. Ellison
Affiliation:
Okmetic AB, Hans Meijers väg 2, SE-583 30 Linköping, Sweden
L. Storasta
Affiliation:
Department of Physics and Measurement Technology, Linköping University, SE-581 83 Linköping, Sweden
E. Janzén
Affiliation:
Department of Physics and Measurement Technology, Linköping University, SE-581 83 Linköping, Sweden
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Abstract

Infrared absorption and resistivity are studied in two different types of semi-insulating (SI) 4H SiC substrates. In type A the silicon vacancy dominates the infrared absorption spectra whereas in type B the UD-1 defect dominates. Both types of substrates are still SI (> 105 Ω cm at 200°C) after annealing at typical CVD growth temperatures (1600°C). The type A material shows a decreasing absorption of the silicon vacancy after 1600°C at the same time as the resistivity decreases from high 107 Ω cm to mid 106 Ω cm measured at 200°C. The thermal activation energy of the resistivity for the type A material is 0.85 eV for temperatures above 250°C both before and after annealing. The type B material does not change with annealing, besides that the absorption increases in intensity with a 1600°C anneal. The resistivity is > 1010 Ω cm at 200°C and the thermal activation energy is 1.4 eV.

The absorption measurements on the silicon vacancy also show that it is still present in the as-grown material after a 1600°C anneal. We interpret this as follows: The silicon vacancy is stable even at 1600°C and does not get mobile at 750°C as earlier suggested.

Type
Research Article
Copyright
Copyright © Materials Research Society 2001

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References

REFERENCES

1. Ellison, A., Magnusson, B., Hemmingsson, C., Magnusson, W., Iakimov, T., Storasta, L., Henry, A., Henelius, N., and Janzéen, E. in Silicon Carbide- Materials, Processing and Devices, edited by Agarwal, A.K., Copper, J.A. Jr, Janzéen, E., and Skowronski, M., (Mater. Res. Soc. Proc. 640, Boston, MA, 2001) H1.2.Google Scholar
2. Sörman, E., Son, N.T., Chen, W.M., Kordina, O., Hallin, C., and Janzéen, E., Phys. Rev. B 64, 2613 (2000).Google Scholar
3. Magnusson, B. Ellison, A., Son, N.T., and Janzéen, E. in Silicon Carbide- Materials, Processing and Devices, edited by Agarwal, A.K., Copper, J.A. Jr, Janzéen, E., and Skowronski, M., (Mater. Res. Soc. Proc. 640, Boston, MA, 2001) H7.11.Google Scholar
4. Wagner, Mt., Magnusson, B., Chen, W.M., Janzéen, E., Sörman, E., Hallin, C., and Lindström, J.L., Phys. Rev. B 62 16555 (2000).Google Scholar
5. Kawasuso, A., Itoh, H., Okada, S., and Okumura, H., J. Appl. Phys. 80 5639 (1996).Google Scholar