Thermal Stability and Dopant Segregation for Schottky Diodes With Ultrathin Epitaxial NiSi2-y

The Schottky barrier height (SBH) of an ultrathin epitaxial NiSi2-y film grown on Si(100) is modified significantly by means of dopant segregation (DS). The DS process begins with the NiSi2-y formation and is followed by dopant implantation and drive-in annealing. The rapid lattice restoration and superior morphological stability upon heat treatment up to 800 degrees C allow the epitaxial NiSi2-y film to take full advantage of the DS process. For drive-in annealing below 750 degrees C, the effective SBH is altered to similar to 0.9-1 eV for both electrons and holes by B-DS and As-DS, respectively, without deteriorating the integrity of the NiSi2-y film.