STM characterization of the Si-P heterodimer

Abstract

We use scanning tunneling microscopy (STM) and Auger electron spectroscopy to study the behavior of adsorbed phosphine (PH${}_3$) 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 $\sim$0.002 Langmuirs of PH${}_3$ results in the adsorption of PH${}_x$ (x=2,3) onto the surface and some etching of Si to form individual Si ad-dimers. Annealing to 350${}^{\circ }$C results in the incorporation of P into the surface layer to form Si-P heterodimers and the formation of short 1-dimensional Si dimer chains and monohydrides. In filled state STM images, isolated Si-P heterodimers appear as zig-zag 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.

arXiv comment6 pages, 4 figures (only 72dpi)

References in corpus (3)

• Atomically precise placement of single dopants in Si
• Towards the fabrication of phosphorus qubits for a silicon quantum computer
• Encapsulation of phosphorus dopants in silicon for the fabrication of a quantum computer

Cited by in corpus (6)

• Initiating and monitoring the evolution of single electrons within atom-defined structures
• The impact of stochastic incorporation on atomic-precision Si:P arrays
• Structural studies of phosphorus induced dimers on Si(001)
• Simultaneous conduction and valence band quantisation in ultra-shallow, high density doping profiles in semiconductors
• Probing the Atomic Arrangement of Sub-Surface Dopants in a Silicon Quantum Device Platform
• STM study of single phosphorus incorporation into silicon by heating PBr3 on Si(100)