Hostname: page-component-cd9895bd7-gvvz8 Total loading time: 0 Render date: 2024-12-27T01:30:45.183Z Has data issue: false hasContentIssue false

Doping Mechanism in Tetrahedral Amorphous Carbon

Published online by Cambridge University Press:  10 February 2011

C W Chen
Affiliation:
Engineering Dept, Cambridge University, Cambridge CB2 1PZ, UK
J Robertson
Affiliation:
Engineering Dept, Cambridge University, Cambridge CB2 1PZ, UK
Get access

Abstract

Doping in hydrogenated amorphous silicon occurs by a process of an ionised donor atom partially compensated by a charged dangling bond. The total energies of various dopant and dopant/bonding combinations are calculated for tetrahedral amorphous carbon. It is found that charged dangling bonds are less favoured because of the stronger Coulombic repulsion in ta-C. Instead the dopants can be compensated by weak bond states in the lower gap associated with odd-membered π-rings or odd-numbered π-chains. The effect is that the doping efficiency is low but there are not charged midgap recombination centres, to reduce photoconductivity or photoluminescence with doping, as occurs in a-Si:H.

Type
Research Article
Copyright
Copyright © Materials Research Society 1998

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. Mott, N F, Adv Phys 16 49(1967)Google Scholar
2. Spear, W E, LeComber, P G, Adv Phys 26 811 (1977)Google Scholar
3. Street, R A, Phys Rev Lett 49 1187 (1982)Google Scholar
4. Robertson, J, Phys Rev B 31 3817 (1985)Google Scholar
5. Street, R A, ‘Hydrogenated Amorphous silicon’, (Cambridge 1991)Google Scholar
6. Meyerson, B, Smith, F W, Solid State Commun 41 68(1982)Google Scholar
7. Jones, D I. and Stewart, A. D., Philos. Mag. B, 46 (1982) 423.Google Scholar
8. Helmbold, A, Hammer, P, Thiele, J U, Rohwer, K, Meissner, D, Phil Mag B 72 335 (1995)Google Scholar
9. Veerasamy, V.S., Yuan, J, Amaratunga, G, Milne, W I, Gilkes, K W R, Weiler, M, Brown, L M, Phys. Rev. B, 48 17954 (1993).Google Scholar
10. Davis, C A, McKenzie, D R, Yin, Y, Kravtchinskaia, E, Amaratunga, G A J, Veerasamy, V S, Phil Mag B 69 1133 (1994)Google Scholar
11. McKenzie, D R, Yin, Y, Marks, N A, Davis, C A, Kravtchinskaia, E, Pailthorpe, B A, Amaratunga, G A J, J Non-Cryst Solids 164 1101 (1993)Google Scholar
12. Kleinsorge, B, et al, Diamond Related Mats (1998)Google Scholar
13. Robertson, J, Davis, C. A., Diamond and Relat. Mater. 4 (1994) 441.Google Scholar
14. Lieber, C M et al, this volume (1998)Google Scholar
15. Kaufinan, H., Metin, S. and Saperstein, D. D., Phys. Rev. B, 39 (1989) 13053 Google Scholar
16. Weich, F, Widany, J, Frauenheim, T, Phys Rev Lett 78 3326 (1997)Google Scholar
17. Stumm, P, Drabold, D A, Fedders, P A, J App Phys 81 1289(1997)Google Scholar
18. Nelson, J S, Stechel, E B, Wright, A F, Plimton, S J, Schultz, P A, Sears, M P, Phys Rev B 52 9354 (1995)Google Scholar
19. Ristein, J, Schäfer, J, Ley, L, Diamond Related Mats 4 508 (1995)Google Scholar
20. Robertson, J, Adv Phys 35 317(1986)Google Scholar
21. Silva, S R P, private communicationGoogle Scholar