Cobalt suicide formation on 6H silicon carbide

Cobalt films (1, 25 and 100 Angstrom) have been directly deposited on top 6 H-SiC(0001) wafers by molecular beam epitaxy and annealed at 500-800 degree s C in UHV. The structure of the metal-semiconductor interface was investig ated by XAFS. The results show that Go-Si bonds were preferentially formed in the 1 A Co films. In the 25 and 100 A Co films only Go-Co bonds were ide ntified. The XRD pattern of the 100 A Co film exhibits a Co (200) peak conf irming the presence of unreacted metal even after annealing at 800 degrees C.