Hydrogen chemisorption on Si surfaces analyzed by magnetic-sector, atom-probe, field-ion microscopy

An atom-probe field-ion microscope was successfully employed for the first time to study semiconductor Si surfaces. Using a magnetic-sector type we have observed pure silicon Si+, monohydride SiH+, and dihydride SiH2+, ions from the well-ordered H-covered (111) and (110) planes, and pure silicon Si+, monohydride SiH+, and silane SiH4+ ions from the disordered (311) areas. This observation is taken as the evidence for the formation of the silicon dihydride and trihydride surface phases suggested by recent ultraviolet photoemission studies.