Interaction of vinyltrimethylsilane with the Si(111)-(7×7) surface

Abstract

Vinyltrimethylsilane (vtms) serves as a ligand in the precursor molecule Cu(I)(vtms)(hfac) used in copper chemical vapor deposition. Investigations of the interaction of vtms with the Si(111)-(7×7) surface utilizing scanning tunneling microscopy, Auger electron spectroscopy, and thermal desorption spectroscopy (TDS) are reported. The adsorption is found to be highly site sensitive with an initial sticking coefficient most probably in excess of 0.03. With the exception of hydrogen, TDS spectra do not display vtms or any other desorbing species. Heating of the vtms covered surface to ≊530 °C leads to the formation of three-dimensional clusters which remain stable in shape and size up to temperatures as high as 1100 °C. We believe the observed clusters consist of carbon and/or SiC. In addition, the observation of (5×5) reconstructed areas between the clusters suggests the deposition of silicon during the annealing process. This indicates that vtms undergoes thermal decomposition on a silicon surface. This is in significant contrast to the observed behavior on metal and insulating surfaces. Consequently we cannot expect contaminant-free interfaces between the Si(111) substrate and copper films grown from the Cu(I)(vtms)(hfac) precursor.

Chemical manipulation of multifunctional hydrocarbons on silicon surfaces

“…While spectroscopic evidence presented above suggests that it binds quite [224], the similar type of addition on Si(111)-7×7 was not singled out by Andersohn et al [372]. Several surface reactions have been considered by this group but no spectroscopic evidence was presented and the paper largely focused on the thermal decomposition of vinyltrimethylsilane that leads to the formation of silicon carbide [372].…”

Complex Thermal Chemistry of Vinyltrimethylsilane on Si(100)-2×1

“…In fact, the three-atom intermediate has been considered by Andersohn et al for VTMS on Si(111)-7×7. 5 It was demonstrated that VTMS adsorption onto the Si(111)-7×7 surface is site-specific. 5 VTMS interacts primarily with the center adatoms (most-depleted of negative charge), and the resulting adsorbed molecules are mostly immobile.…”

Magic islands and barriers to attachment: ASi/Si(111)7×7growth model

“…1,2,5 The experimental value of χ=0.75 for T =680 K and T =770 K was reported in Ref. 13. In this experiment, samples were prepared at a given temperature by deposition of ≈0.15 BL Si on the Si(111)7×7 surface followed by rapid quenching to room temperature.…”