p(2 x 2) phase of buckled dimers of Si(100) observed on n-type substrates below 40 K by scanning tunneling microscopy -: art. no. 286104

We have investigated the basic surface reconstruction of Si(100) on well defined surfaces fabricated on various substrates at low temperatures (-80 K) by scanning tunneling microscopy. Below 40 K, the single p(2x2) phase, a phase never observed before, was observed exclusively on n-type substrates doped in the range of 0.002 to 0.017 Omega cm. We also exclude the possibility of the (2x1) symmetric dimer commonly observed at low temperature (-10 K) being the basic surface reconstruction by showing that a buckled dimer can be flip-flopped by the tunneling tip.