Tailoring the Ti/4H-SiC Schottky barrier by ion irradiation

The effects of ion irradiation on the Ti/4H-SiC Schottky barrier are discussed. The Ti/SiC interfacial region was modified by irradiating Schottky diodes with 8 MeV Si+4 ions at fluences between 1x10(9) and 1x10(12) ions/cm(2). By increasing the ion fluence, an increase of the Schottky barrier Phi(B) occurs, from the value of 1.05 eV after preparation to the value of 1.21 eV after irradiation at a fluence of 1x10(12) ions/cm(2), without substantial changes in the ideality factor (n=1.09). Along with the barrier height increase, a decrease of the leakage current of about two orders of magnitude was observed after irradiation. The results were interpreted in terms of the structural and electrical modification of the interfacial region.