Electronic properties of then-doped hydrogenated silicon (100) surface and dehydrogenated structures at 5 K

Abstract

We present a comparative study of the electronic properties of the clean Si͑100͒ and the hydrogenated Si͑100͒:H surfaces performed with a low-temperature ͑5 K͒ scanning tunneling microscope. Various surface structures such as single silicon dangling bonds and bare silicon dimers created by local desorption of hydrogen atoms from the Si͑100͒:H surface are also investigated. The experimental scanning tunneling spectroscopy ͑STS͒ curves acquired locally on each of these structures are compared with STS measurements performed on the Si͑100͒ and Si͑100͒:H surfaces. First principle density-functional theory calculations of the projected local density of states, taking into account the influence of the dopant atoms ͑As͒, enable to assign the observed STS spectra.

Atomic scale fabrication of dangling bond structures on hydrogen passivated Si(001) wafers processed and nanopackaged in a clean room environment

“…It shows a characteristic "butterfly" contrast in the empty state image. These observations are in agreement with previous STM measurements performed at RT [23], 80 K [24] and 5 K [11]. Interestingly, the buckled, asymmetric configuration of the isolated Si bare dimer, where it is tilted with respect to the surface plane by about 19 • , is often considered as the native geometry [24].…”

“…This is coming from the narrow states of the Si(0 0 1) DB dimers, which are located at a +1.5 eV energy (Fig. 5) and which correspond to * antibonding states of the Si dimer back bonds, as reported by Bellec et al [11]. Such description of observed dI/dU maxima is also in agreement with STS data obtained for bare Si(0 0 1) surface [26].…”

“…A reconstructed and atomically flat surface like Si(0 0 1):H is then required, as it can provide regular and aligned atomic rows and would thus be an ideal platform for STM-based lithography [6][7][8][9]. This technique enables the formation of well-defined, nanoscale DB patterns: from single and double DBs [7,8,[10][11][12] to DB lines and Si-nanopads [6,9,[13][14][15].…”

Atomic-scale study of the adsorption of calcium fluoride on Si(100) at low-coverage regime

“…4(g), and they reveal that the surface gap is slightly enlarged when the dI-dV measurements are performed on the dark structures compared to the bare silicon surface, in particular for V s ranging between 0 and +1 V. This difference mainly concerns the unoccupied π * surface states, which are delocalized along the coupled Si dimers of the silicon dimer rows. 29 This suggests that coupled Si dimers do not exist anymore in the type-A areas, most probably due to the chemical reaction of CaF 2 molecules with the silicon surface.…”

Subatomic electronic feature from dynamic motion of Si dimer defects in Bi nanolines on Si(001)

“…A symmetric butterflylike appearance has been observed in empty state STM images of isolated dimers, despite being physically asymmetrically buckled [12,13]. The butterflylike appearance consists of two dominant round outer lobes, and a central sharp lobe oriented perpendicular to the Si dimer.…”