A comprehensive experimental study was made of the Si(001) c(4 x 4) surface reconstruction by using scanning tunnelling microscopy, Auger electron spectroscopy and reflection high-energy electron diffraction. The Si(001) samples were kept under ultra-high vacuum at 600C until the c(4 x 4) reconstruction was evident in reflection high-energy electron diffraction. The reconstruction was related to carbon as could be seen from Auger electron spectroscopy and the formation of β-SiC after further annealing. Carbon originating from hydrocarbon compounds in the vacuum background was cracked after adsorption on the surface at these high temperatures. Scanning tunnelling microscopy revealed a number of different structures within the c(4 x 4) unit mesh; indicating that the surface structure was influenced by defects. Imaging the c(4 x 4) reconstructed surface under high bias voltages revealed dark features that were attributed to screening effects by sub-surface defects.

Influence of Carbon on the Formation of the Si(001) c(4 x 4) Surface Reconstruction. H.Nörenberg, G.A.D.Briggs: Surface Science, 1999, 433-435, 397-400