Hostname: page-component-78c5997874-fbnjt Total loading time: 0 Render date: 2024-10-31T23:08:58.173Z Has data issue: false hasContentIssue false

A physically-based SPICE model for the leakage current in a-Si:H TFTs accounting for its dependencies on process, geometrical, and bias conditions

Published online by Cambridge University Press:  17 March 2011

Peyman Servati
Affiliation:
Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, CanadaN2L 3G1
Arokia Nathan
Affiliation:
Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, CanadaN2L 3G1
Andrei Sazonov
Affiliation:
Department of Electrical & Computer Engineering, University of Waterloo, Waterloo, Ontario, CanadaN2L 3G1
Get access

Abstract

We have developed a physically-based analytical model of the static current-voltage characteristics of hydrogenated amorphous silicon (a-Si:H) inverted staggered thin film transistors (TFTs) in the reverse (leakage) regime (VG<0,VD>0). We studied analytically (based on measurement data) the dependence of the leakage current on process parameters (i.e. the deposition-temperature-dependent phosphorus diffusion profile in the a-Si:H active layer), geometrical parameters (i.e. a-Si:H thickness, source/drain overlap areas), and operating conditions (i.e. VG, VD). The derived analytical model is implemented in HSPICE. The simulated and measured results are in good agreement with a discrepancy of less than 5%.

Type
Research Article
Copyright
Copyright © Materials Research Society 2000

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. Shannon, J. M. and Morgan, B. A., Hole transport via dangling-bond states in amorphous hydrogenated silicon nitride, J. of Appl. Phys., 86, 3 (Aug. 1999) pp.15481551.Google Scholar
2. Lemmi, F. and Street, R. A., Temperature dependent transient leakage currents in amorphous silicon thin film transistors, Mat. Res. Soc. Symp. Proc., 557 (1999) pp.671676.Google Scholar
3. Yamaji, Y., Ikeda, M., Akiyama, M. and Endo, T., Characterization of photo leakage current of amorphous silicon thin-film transistors, Jpn. J. Appl. Phys., 38 (1999) pp.62026206.Google Scholar
4. Street, R. A. and Thompson, M. J., Electronic states at the hydrogenated amorphous silicon/silicon nitride interface, Appl. Phys. Lett., 45 (7) (Oct. 1984) pp.769771.Google Scholar
5. Murthy, R. V. R., Pereira, D., Park, B., Nathan, A. and Chamberlain, S. G., Compact SPICE modeling and design optimization of low leakage a-Si:H TFTs for large-area imaging systems, Mat. Res. Soc. Symp. Proc., 507 (1998) pp.415420.Google Scholar
6. Murthy, R. V. R., Servati, P., Nathan, A. and Chamberlain, S. G., Optimization of n+μc-Si:H contact layer for low leakage current in a-Si:H thin film transistors, J. Vac. Sci. Tech. A, 18 (2)(Mar. 2000) pp.685687.Google Scholar
7. Kawachi, G., Graeff, C. F. O., Brandt, M. S. and Stutzmann, M., Carrier Transport in amorphous silicon-based thin-film transistors studied by spin-dependent transport, Phys. Rev. B, 54 (Sept. 1996) pp.79577964.Google Scholar
8. Park, H.-R., Kwon, D. and Cohen, J. D., Electrode interdependence and hole capacitance in capacitance-voltage characteristics of hydrogenated amorphous silicon thin-film transistor, J. Appl. Phys., 83 (12) (Jun. 1998) pp.80518056.Google Scholar