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A Fully Self-Aligned Amorphous Silicon Tft Technology for Large Area Image Sensors and Active-Matrix Displays

Published online by Cambridge University Press:  10 February 2011

M J Powell
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
C Glasse
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
J E Curran
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
J R Hughes
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
I D French
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
B F Martin
Affiliation:
Philips Research Laboratories, Redhill, Surrey, RHI 5HA, UK
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Abstract

We have developed a fully self-aligned amorphous silicon TFT technology, which is suitable for large area image sensors and active matrix displays. Self-alignment is achieved by defining the top nitride by back exposure and then forming source and drain contacts by ionimplantation and silicidation. We incorporate a low resistance gate metallisation process, by using Al metal, capped by Cr. We have compared the process of forming the silicide after the ion-implantation step, with a new process of forming the silicide first and then implanting through the formed silicide. We find a significant advantage to the latter method, where we can achieve a higher doping level and reduced contact resistance. We have therefore optimised our process based on this method. Transistor characteristics as a function of channel length for both methods show the improved contact resistance, obtained with the latter method. We obtain field effect mobilities of 0.7cm2V−1s−1, measured in the saturated region, for a channel length of 8μm.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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References

REFERENCES

[1] Powell, M J, Chapman, J A, Knapp, A G, French, I D, Hughes, J R, Pearson, A D, Edwards, M J, Ford, R A, Hemings, M C, Hill, O F, Nicholls, D H and Wright, N K, Proceedings of SID 29 227 (1988)Google Scholar
[2] Powell, M J, French, I D, Hughes, J R, Bird, N C, Davies, O S, Glasse, C and Curran, J E, Materials Research Society Symposium Proceedings 258 1127 (1992)Google Scholar
[3] Suzuki, K, Aoki, T, Ikeda, M, Okada, Y, Zohta, Y and Ide, K, SID Symposium Digest 146 (1983)Google Scholar
[4] Ishii, Y, Takafuji, Y, Yano, K, Take, H and Funada, F, SID Symposium Digest 295 (1985)Google Scholar
[5] Ugai, Y, Murakami, Y, Tamamura, J and Aoki, S, SID Symposium Digest 308 (1984)Google Scholar
[6] Akiyama, M, Uchikoga, S, Sakakubo, T, Koizumi, T, Suzuki, K and Tbaraki, N, SID Symposium Digest 10 (1991)Google Scholar
[7] Nishida, S, Uchida, H and S Kaneko, Materials Research Society Symposium Proceedings 219 303 (1991)Google Scholar
[8] Akiyama, M, Ikeda, Y, Ikeda, M and Suzuki, K, SID Symposium Digest 887 (1993)Google Scholar
[9] Kakkad, R, Jinnai, T, Miura, Y, Honjo, M, Shibusawa, M, Ibaraki, N, Obara, T, Matsunaka, S and Ito, H, Journal of SID 4/2 101 (1996).Google Scholar
[10] Takeuchi, S, Sunata, T, Ugai, Y, Aoki, S and Matsumura, M, AMLCD-94, Digest of Technical Papers 108 (1994)Google Scholar
[11] Ibaraki, N, Materials Research Society Symposium Proceedings 336 749 (1994)Google Scholar
[12] Kosvarian, A and Shannon, J M, J. Electronic Materials (1998), submitted for publicationGoogle Scholar
[13] French, I D, Deane, S C, Murley, D T, Hewett, J, Gale, I G and Powell, M J, Materials Research Society Symposium Proceedings 467 875 (1997)Google Scholar