Ion-Beam Induced Modifications of Titanium Schottky Barrier on 4H-SiC
The effects of ion irradiation on the Ti/4H-SiC Schottky barrier are discussed. The Ti/SiC interfacial region of test Schottky diodes was irradiated with 8 MeV Si+4 ions at fluences between 1×109 and 1×1012 ions/cm2. By increasing ion fluence, an increase of the Schottky barrier FB was observed, from FB=1.05 eV in the non-irradiated sample to FB =1.21 eV after irradiation at the highest fluence, accompanied by a decrease of the leakage current. Using different experimental analytical techniques enabled us to correlate the modification of the interfacial region with the contacts electrical behaviour. In particular, the structural and electrical modifications in the nearinterface region (different orientation of the Ti film, defects in the epilayer, dopant deactivation) were responsible for the change of the Ti barrier after irradiation.
Roberta Nipoti, Antonella Poggi and Andrea Scorzoni
F. Roccaforte et al., "Ion-Beam Induced Modifications of Titanium Schottky Barrier on 4H-SiC", Materials Science Forum, Vols. 483-485, pp. 729-732, 2005