Radiation Hardness for Silicon Oxide and Aluminum Oxide on 4H-SiC
The radiation hardness of two dielectrics, SiO2 and Al2O3, deposited on low doped, n-type 4H-SiC epitaxial layers has been investigated by exposing MOS structures involving these materials to MeV proton irradiation. The samples are examined by capacitance voltage (CV) measurements and, from the flat band voltage shift, it is concluded that positive charge is induced in the exposed structures detectable for fluence above 1×1011 cm-2. The positive charge increases with proton fluence, but the SiO2/4H-SiC structures are slightly more sensitive, showing that Al2O3 can provide a more radiation hard passivation, or gate dielectric for 4H-SiC devices.
Robert Stahlbush, Philip Neudeck, Anup Bhalla, Robert P. Devaty, Michael Dudley and Aivars Lelis
A. Hallén and S. S. Suvanam, "Radiation Hardness for Silicon Oxide and Aluminum Oxide on 4H-SiC", Materials Science Forum, Vol. 924, pp. 229-232, 2018