Ion beam synthesis of heteroepitaxial erbium silicide layers

Si(111) substrates were implanted with 70 or 90 keV 166Er atoms to doses from 1.3 to 2.0×1017 cm−2 at substrate temperatures from 450 to 530°C. During implantation, the Si substrates were tilted by 7° to minimize the channeling effect. The Er silicide layers formed under these conditions are not as good as Co silicide layers formed by Co implantation under similar conditions and the reason is discussed. One of the best results is an annealed sample containing a discontinuous epitaxial ErSi1.7 layer with χmin of 40%. Rutherford backscattering and channeling spectrometry, X-ray diffraction and transmission electron microscopy have been used to study this heteroepitaxial ErSi1.7 layer, showing that the epilayer is compressively strained and the azimuthal orientation of the epilayer is ErSi1.7[0001]∥Si[111] and ErSi1.7(1010)∥Si(112)