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Band Alignments of High-K Dielectrics on Si and Pt

Published online by Cambridge University Press:  10 February 2011

J Robertson ,
E Riassi ,
J-P Maria  and
A I Kingon
J Robertson
Affiliation:
Engineering Dept, Cambridge University, Cambridge CB2 1PZ, UK
E Riassi
Affiliation:
Engineering Dept, Cambridge University, Cambridge CB2 1PZ, UK
J-P Maria
Affiliation:
Dept of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695-7919, USA.
A I Kingon
Affiliation:
Dept of Materials Science and Engineering, North Carolina State University, Raleigh, NC 27695-7919, USA.
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Abstract

Materials with a high dielectric constant (K) such as tantalum pentoxide (Ta2O5) and barium strontium titanate (BST) are needed for insulators in dynamic random access memory capacitors and as gate dielectrics in future silicon devices. The band offsets of these oxides must be over 1 eV for both electrons and holes, to minimise leakage currents due to Schottky emission. We have calculated the band alignments of many high K materials on Si and metals using the method of charge neutrality levels. Ta2O5 and BST have rather small conduction band offsets on Si, because the band alignments are quite asymmetric. Other wide gap materials Al2O3, Y2O3, ZrO2 and ZrSiO4 are found to have offsets of over 1.5 eV for both electrons and holes, suggesting that these are preferable dielectrics. Zirconates such as BaZrO3 have wider gaps than the titanates, but they still have rather low conduction band offsets on Si. The implications of the results for future generations of MOSFETs and DRAMS are discussed.

Type
Research Article
Information
MRS Online Proceedings Library (OPL) , Volume 592 , 1999 , 87
Copyright
Copyright © Materials Research Society 2000

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References

REFERENCES

1.Kwon, K W, Kang, C S, Park, S O, Kang, H K, Ahn, S T, IEEE Trans ED 43 919 (1996)Google Scholar
2.Matsui, Y et al. , IEEE ED Lett 17 431 (1996)Google Scholar
3.Dietz, G W, Antpohler, W, Klee, M, Waser, R, J App Phys 78 6113 (1995)Google Scholar
4.Zurcher, P et al. , Mat Res Soc Symp Proc 541 11 (1999); A Grill et al, Mat Res Soc Symp Proc 541 89 (1999)Google Scholar
5.Alers, G B, Werder, D J, Chabal, Y, Lu, H C, Gusev, E P, Garfunkel, E, Gustafsson, T, Urdahl, R S, App Phys Lett 73 1517 (1998)Google Scholar
6.Keister, J W, Rowe, J E, Kolodziej, J J, Niiki, H, Madey, T E, Lucovsky, G, J Vac Sci Technol B 17 1831 (1999)Google Scholar
7.Robertson, J, Chen, C W, App Phys Lett 74 1168 (1999); Mat Res Soc Symp Proc 541 443 (1999)Google Scholar
8.Chatterjee, A et al. , IEDM Tech Digest 777 (1998)Google Scholar
9.Maria, J-P. and Kingon, A. I., Submitted to J. Mater. Res., Aug, (1999)Google Scholar
10.Manchanda, L et al. , Tech Dig IEDM p605 (1998)Google Scholar
11.Copel, M, Gribelyuk, M, Gusev, E, App Phys Lett 76 436 (2000)Google Scholar
12.Kim, H S, Gilmer, D C, Campbell, S A, Polla, D L, App Phys Lett 69 3860 (1996)Google Scholar
13.Wilk, G D, Wallace, R M, Antony, J M, J App Phys 87 484 (2000)Google Scholar
14.Rhoderick, E H, Williams, R H, ‘Metal Semiconductor Contacts’, (Oxford, 1988)Google Scholar
15.Monch, W, Phys Rev Lett 58 1260 (1986); Surface Sci 299 928 (1994)Google Scholar
16.Kurtin, S, McGill, T C, Mead, C A, Phys Rev Lett 30 1433 (1969)Google Scholar
17.Schluter, M, Thin Solid Films 93 3 (1982)Google Scholar
18.Monch, W, App Surface Sci 92 367 (1996)Google Scholar
19.Tersoff, J, Phys Rev B 30 4874 (1984)Google Scholar
20.Cardona, M, Christensen, N E, Phys Rev B 35 6182 (1987)Google Scholar
21.Robertson, J, Warren, W L, Tuttle, B A, Dimos, D, Smyth, D M, App Phys Lett 63 1519 (1993)Google Scholar
22.Robertson, J, Chen, C W, Warren, W L, Gutleben, C D, App Phys Lett 69 1704 (1996)Google Scholar
23.French, R H, Glass, S J, Ohuchi, F S, Xu, Y N, Ching, W Y, Phys Rev B 49 5133 (1994)Google Scholar
24.French, R H, J Am Ceram Soc 73 477 (1990)Google Scholar
25.Pascual, J, Camassel, J, Mathieu, H, Phys Rev B 18 5606 (1978)Google Scholar
26.Palik, E D, ‘Handbook of Optical Properties of Solids’, vol 1–3, (Academic Press, 1985)Google Scholar
27.Scott, J F, Ann Rev Mats Sci 28 79 (1998)Google Scholar
28.Oehrlein, G S, J App Phys 55 3715 (1984)Google Scholar
29.Neville, R C, Mead, C A, J App Phys 43 4657 (1972)Google Scholar
30.Abe, K, Komatsu, S, Jpn J App Phys 31 2985 (1992)Google Scholar
31.Shimizu, T, Gotoh, N, Shinozaki, N, Okushi, H, App Surf Sci 117 400 (1997)Google Scholar
32.Copel, M, Duncombe, P R, Neumayer, D A, Shaw, T M, Tromp, R M, App Phys Lett 70 3227 (1997)Google Scholar
33.Gutleben, C D, App Phys Lett 71 3444 (1997)Google Scholar
34.Harrison, W A, ‘Electronic Structure’, (W H Freeman, San Francisco, 1980)Google Scholar