LEED and angle-resolved AES studies on Si-, P-, and Cl-adsorbed Ni(100) surfaces

A number of adsorbed structures produced by chemisorption of SiH4, PH3 and HCl on Ni(100) surfaces have been investigated by LEED and angle-resolved Auger electron spectroscopy (ARAES). The room-temperature adsorption of SiH4 and PH3 produces the disordered structures, from which the Si(92 eV) and P (120 eV) Auger emissions respectively show a cos theta profile. The Si, P and Cl (180 eV) Auger emissions from the c(2*2)-Si, (2 square root 2* square root 2)R45 degrees -Si, ( square root 5* square root 5)R26.6 degrees -P, c(2*2)-HCl and c(2*2)-Cl structures show the anisotropic angular features as in the case of the c(2*2)-S and -Se on Ni(100) surfaces.