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Temperature and Frequency Dependent Characteristics of Amorphous Silicon thin film Transistors

Published online by Cambridge University Press:  15 February 2011

H. C. Slade
Affiliation:
University of Virginia, Thornton Hall, Charlottesville, VA 22903–2442
M. S. Shur
Affiliation:
University of Virginia, Thornton Hall, Charlottesville, VA 22903–2442
M. Hack
Affiliation:
Xerox PARC, 3333 Coyote Hill Rd., Palo Alto, CA 94304
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Abstract

On the basis of our experimental studies of the temperature dependence of amorphous silicon thin film transistor current-voltage and capacitance-voltage characteristics, we have developed an analytical device model suitable for implementation in circuit simulators. This model describes the above-threshold (on) current and the subthreshold (off) current [1]. In addition, the model is able to incorporate changes in the distribution of localized states which arise from thermal and/or bias stress. In this paper, we identify the temperature-dependent parameters, which describe the temperature dependence of both the on and off currents, and we model the leakage current at large negative gate biases. The modeling results are in good agreement with our experimental data. We also discuss capacitance-voltage characteristics of amorphous silicon thin film transistors for varying gate lengths, temperatures, and frequencies. The measured capacitance-voltage characteristics show strong frequency dispersion, which is related to the trap-limited transport of carriers in the channel. The characteristic time constant, which determines when the channel capacitance becomes dependent on frequency, is on the order of the transit time calculated with the field-effect mobility and the electric field. The field-effect mobility takes into account carrier trapping by the localized states and is a function of gate voltage and temperature.

Type
Research Article
Copyright
Copyright © Materials Research Society 1995

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References

REFERENCES

[1] Shur, M., Jacunski, M.D., Slade, H.C., and Hack, M., J. Soc. Info. Displays (to be published).Google Scholar
[2] Shur, M. and Hack, M., J. Appl. Phys., 55 (10), 3831 (1984).Google Scholar
[3] Lee, K., Shur, M., Fjeldly, T., and Ytterdal, T., Semiconductor Device Modeling for VLSI. (Englewood Cliffs: Prentice Hall, 1993).Google Scholar
[4] Morgan, P.N., Milne, W.I., Deane, S.C., and Powell, M.J., presented at ICAS, Cambridge, UK (1993).Google Scholar
[5] Hack, M., Shaw, J., LeComber, P., and Williams, M., Jap. J. Appl. Phys., 29 (12), L2360, (1990).Google Scholar
[6] Slade, H.C., Gelmont, B., Globus, T., Shur, M., and Hack, M., Elec. Chem. Soc. Proc., 94–35, 207 (1995).Google Scholar
[7] van Berkei, C. in Amorphous and Microcrystalline Semiconductor Devices. Vol. 2, edited by Kanicki, J. (Artech House, Mass. 1992), p. 412.Google Scholar
[8] Shur, M., Hyun, C., and Hack, M., J. of Appl. Phys., 59 (7), 2488 (1986).Google Scholar