Proton Radiation Hardening Of Silicon Oxynitride Gate Nmosfets Formed By Nitrogen Implantation Into Silicon Prior To Oxidation

Silicon oxynitride (SiOxNy) insulators have been obtained by low-energy nitrogen ion implantation into Si substrates prior to conventional or rapid thermal oxidation. Theses films have been used as gate insulators in enhancement nMOSFETs and MOS capacitors. MOS capacitors were used to obtain capacitance-voltage (C-V) measurements. A relative dielectric constant of 3.9 was adopted to extract the Equivalent Oxide Thickness (EOT) of films from C-V curves, resulting in values between 5nm and 12nm. nMOSFETs were bombarded with H+ ion beams (energy of O.17MeV and doses of 0, 1012, 1013 and 1O14 protons/cm2) to investigate radiation hardening. nMOSFET electrical characteristics, such as threshold voltage (VT), transconductances (Gm) and sub-threshold slope (S), were extracted before and after proton radiation. For high dose bombardment, VT, S are increased and Gm is reduced. These oxynitride gate device performance degradation was significant only for doses > 1012 protons/cm2.12229233Gopal, R., Ahmad, S., Effect of proton-induced damage on the performance of enhancement mode MOSFET (1998) Phys. Stat. Solidi (a), 168, pp. 129-141. , JulFleetwood, D.M., Winokur, P.S., Riewe, L.C., Flament, O., Paillet, P., Leray, J.L., The role of electron transport and trapping in MOS total-dose modeling (1999) IEEE Trans. on Nuclear Science, 46 (6), pp. 1519-1525. , DecSaks, N.S., Simons, M., Fleetwood, D.M., Yount, J.T., Lenahan, P.M., Klein, R.B., Radiation effects in oxynitrides grown in N2O (1994) IEEE Trans. on Nuclear Science, 41 (6), pp. 1854-1863. , DecFleetwood, D.M., Saks, N.S., Oxide, interface, and border traps in thermal, N2O, and nitrided oxides (1996) J. Appl. Phys, 79 (3), pp. 1583-1594. , FebDiniz, J.A., Tatsch, P.J., Kretly, L.C., Queiroz, J.E.C., Godoy Fo, J., Formation of ultra-thin oxinitride films by low-energy nitrogen implantation (1995) Mat. Res. Soc. Proceedings, Boston, MA, 396. , DecDiniz, J.A., Sotero, A.P., Lujan, G.S., Tatsch, P.J., Swart, J.W., High quality ultra-thin oxynitride films formed by low-energy nitrogen implantation into silicon with additional plasma or thermal oxidation (2000) Nuclear Instruments and Methods in Physics Research, B, 166-167, pp. 64-69. , MayMessenger, S.R., Xapsos, M.A., Burke, E.A., Walters, R.J., Summers, G.P., Proton displacement damage and ionizing dose for shielded devices in space (1997) IEEE Trans. on Nuclear Science, 44 (6), pp. 2169-2173. , DecZiegler, J.F., Biersack, J.B., Littmark, U., (1985) The Stopping and Range of Ions in Solids, 1. , Pergammon Press: New YorkSRIM Version 96.00Rax, B.G., Lee, C.I., Johnston, A.H., Degradation of precision reference devices in space environments (1997) IEEE Trans. on Nuclear Science, 44 (6), pp. 1939-1944. , DecOsborn, J.V., Lacoe, R.C., Mayer, D.C., Yabiku, G., Total dose hardness of three commercial CMOS microelectronics foundries (1998) IEEE Trans. on Nuclear Science, 45 (3), pp. 1458-1463. , JunDiniz, J.A., Tatsch, P.J., Prudenzi, M.A.A., Krely, L.C., Herion, J.K., Nitrided-oxide films formed by low-energy and medium-dose nitrogen implantation (1996) Proceedings of XI Congress of the Brazilian Microelectronics Society, Águas de Lindoia-SP-Brazil, 1, pp. 402-407. , JulKamgar, A., Clemens, J.T., Ghetti, A., Liu, C.T., Lloyd, E.J., Reduced electron mobility due to nitrogen implant prior to the gate oxide growth (2000) IEEE Electron Dev. Lett., 21 (5), pp. 227-229. , Ma