ESD experiments in relation with atom manipulations in STM: H− and D− ion ejection from Si(1 1 1):H(1 × 1) N and P doped crystals during low energy electron collisions

This paper deals with experimental studies of H− ion desorption from silicon crystal surfaces Si(1 1 1):H(1 × 1) with various impurity levels and nature. Following previous studies carried out on a “high resistivity” n (∼10 Ω cm) substrate, new investigations show the absence of isotopic effect for hydrogen ion desorption. In addition for 0.23 Ω cm n-type and 0.05 Ω cm p-type silicon (1 1 1) crystals the electron bombardment induces changes in reference potential, in desorption threshold and in energy position of resonant desorption. These variations are consistent with a progressive incorporation of hydrogen atoms into the bulk material. The final discussion introduces elements supporting the high energy threshold and the isotope dependence controlling the atom manipulation yields in scanning tunnel microscope. Here again the electron beam is assumed to trigger hydrogen insertion into the bulk after crossing a surface diffusion barrier.