STM characterization of the Si-P heterodimer.
PHYS REV B
, Article 195303. 10.1103/PhysRevB.69.195303.
We use scanning tunneling microscopy (STM) and Auger electron spectroscopy to study the behavior of adsorbed phosphine (PH3) on Si(001), as a function of annealing temperature, paying particular attention to the formation of the Si-P heterodimer. Dosing the Si(001) surface with similar to0.002 langmuirs of PH3 results in the adsorption of PHx (x=2,3) onto the surface and etching of Si to form individual Si ad-dimers. Annealing to 350 degreesC results in the incorporation of P into the surface layer to form Si-P heterodimers and the formation of short one-dimensional Si dimer chains and monohydrides. In filled state STM images, isolated Si-P heterodimers appear as zigzag features on the surface due to the static dimer buckling induced by the heterodimer. In the presence of a moderate coverage of monohydrides this static buckling is lifted, rending the Si-P heterodimers invisible in filled state images. However, we find that we can image the heterodimer at all H coverages using empty state imaging. The ability to identify single P atoms incorporated into Si(001) will be invaluable in the development of nanoscale electronic devices based on controlled atomic-scale doping of Si.
|Title:||STM characterization of the Si-P heterodimer|
|Keywords:||SCANNING-TUNNELING-MICROSCOPY, QUANTUM COMPUTER, SI(001) SURFACE, PHOSPHINE, SI(100), SILICON, ADSORPTION, PHOTOEMISSION, PHOSPHORUS, HYDROGEN|
|UCL classification:||UCL > School of BEAMS > Faculty of Maths and Physical Sciences > London Centre for Nanotechnology|
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