Hostname: page-component-76fb5796d-5g6vh Total loading time: 0 Render date: 2024-04-27T00:10:25.442Z Has data issue: false hasContentIssue false

Gate Stack Reliability of High-Mobility 4H SiC Lateral MOSFETs with Deposited Al2O3 Gate Dielectric

Published online by Cambridge University Press:  31 January 2011

Daniel J Lichtenwalner
Affiliation:
djlichte@ncsu.edu, North Carolina State University, Materials Science and Engineering, Raleigh, North Carolina, United States
Veena Misra
Affiliation:
vmisra@ncsu.edu, North Carolina State University, Electrical and Computer Engineering, Raleigh, North Carolina, United States
Sarit Dhar
Affiliation:
Sarit_Dhar@cree.com, CREE, Inc., Power Research and Development, Research Triangle Park, North Carolina, United States
Sei-Hyung Ryu
Affiliation:
sei-hyung_ryu@cree.com, CREE, Inc., Power Research and Development, Research Triangle Park, North Carolina, United States
Anant Agarwal
Affiliation:
Anant_Agarwal@cree.com, CREE, Inc., Power Research and Development, Research Triangle Park, North Carolina, United States
Get access

Abstract

Lateral nMOSFETs have been fabricated on 4H-SiC utilizing deposited dielectrics and gate-last processing. A bi-layer dielectric was utilized consisting of thin nitrided SiO2 covered by 25nm of Al2O3 deposited using atomic layer deposition. Field-effect mobility and threshold voltage (VT) were found to vary with SiC nitric oxide (NO) anneal temperature. High peak mobility values of 106 cm2/V·s were obtained, with a corresponding VT of 0.8 V, using an 1175 °C 20 min NO anneal of the SiC before Al2O3 deposition. Constant voltage stressing (CVS) of the gate (3 MV/cm) for 1000s induces a VT increase of only 0.12 V for the devices stressed at RT, whereas a VT shift of 0.34 V occurs for devices stressed at 150 °C. Heating unstressed devices to 200 °C reveals a stable VT with temperature. Negative charge in the gate region allows for the attainment of positive VT, while VT stability does not suffer.

Type
Research Article
Copyright
Copyright © Materials Research Society 2010

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

1. Dhar, S., Wang, S., Williams, J.R., Pantelides, S.T., and Feldman, L.C., MRS Bull. 30, 288 (2005).10.1557/mrs2005.75Google Scholar
2. Afanas'ev, V.V., Ciobanu, F., Dimitrijev, S., Pensl, G., and Stesmans, A., J. Phys.: Condens. Matter 16, S1839 (2004).Google Scholar
3. Chung, G.Y., Tin, C.C., Williams, J.R., McDonald, K., Chanana, R.K., Weller, R.A., Pantelides, S. T., Feldman, L.C., Holland, O.W., Das, M.K., and Palmour, J.W., IEEE Electron Device Lett. 22(4), 176 (2001).10.1109/55.915604Google Scholar
4. Lu, C.-Y., Cooper, J.A. Jr , Tsuji, T., Chung, G., Williams, J.R., McDonald, K., and Feldman, L. C., IEEE Trans. Electron Dev., 50(7), 1582 (2003).Google Scholar
5. Lelis, A.J., Habersat, D., Green, R., Ogunniyi, A., Gurfinkel, M., Suehle, J., and Goldsman, N., IEEE Trans. Electron Devices, 55(8), 1835 (2008).10.1109/TED.2008.926672Google Scholar
6. Zetterling, C.-M., Östling, M., Yano, H., Kimoto, T., Matsunami, H., Linthicum, K., and Davis, R. F., Mat. Sci. Forum 338-342, 1315 (2000).10.4028/www.scientific.net/MSF.338-342.1315Google Scholar
7. Tanner, C.M. and Perng, Y.-C., Frewin, C., Saddow, S.E., and Chang, J.P., Appl. Phys. Lett. 91, 203510 (2007).10.1063/1.2805742Google Scholar
8. Pensl, G., Beljakowa, S., Frank, T., Gao, K., Speck, F., Seyller, T., Ley, L., Ciobanu, F., Afanas'ev, V., Stesmans, A., Kimoto, T., and Schöner, A., Phys. Stat. Sol. (b) 245(7), 1378 (2008).10.1002/pssb.200844011Google Scholar
9. Hatayama, T., Hino, S., Miura, N., Oomori, T., and Tokumitsu, E., IEEE Trans. Electron Dev. 55(8), 2041 (2008).10.1109/TED.2008.926647Google Scholar
10. Alshareef, H.N., Quevedo-Lopez, M., Wen, H.C., Harris, R., Kirsch, P., Majhi, P., Lee, B.H., Jammy, R., Lichtenwalner, D. J., Jur, J. S., and Kingon, A. I., Appl. Phys. Lett. 89, 232103 (2006).10.1063/1.2396918Google Scholar
11. Lee, B.-M., Lichtenwalner, D.J., Agustin, M., Arghavani, R., Tang, X., Gandikota, S., Ku, V., and Misra, V., ECS Trans. 13, 123 (2008).10.1149/1.2911491Google Scholar
12. Suri, R., Lee, B., Lichtenwalner, D J., Biswas, N., and Misra, V., Appl. Phys. Lett. 93, 193504 (2008).10.1063/1.3007978Google Scholar
13. Stathis, J.H. and Zafar, S, Microelectron. Reliab. 46, 270 (2006).10.1016/j.microrel.2005.08.001Google Scholar
14. Allerstam, F., Ólafsson, H. Ö., Gudjónsson, G., Dochev, D., Sveinbjörnsson, E.Ö., Rödle, T. and Jos, R., J. Appl. Phys. 101, 124502 (2007).10.1063/1.2745321Google Scholar