Dynamic reflection high-energy electron diffraction observation of 3C-SiC(001) surface reconstruction under Si2H6 beam irradiation

Abstract

The transition of 3C-SiC(001) surface superstructures under Si2H6 gas molecular beam irradiation was dynamically observed by reflection high-energy electron diffraction. Starting from the C-terminated c(2×2) structure, the surface structure changed in the order of c(2×2)→(2×1)→(5×2)→(3×2) with continuing irradiation. The amounts of Si2H6 dose required for the transitions c(2×2)→(5×2) and c(2×2)→(3×2) were approximately 1.16 and 1.36 times as much as that for c(2×2)→(2×1). These ratios are interpreted as the relative amount of the constituent Si atoms of the superstructures. This experimental result supports the simple dimer model for (2×1) (1 monolayer of Si) and the additional dimer model for (5×2) (1.2 monolayer) and (3×2) (1.33 monolayer), respectively, as the proper configurations of these surface superstructures.

Vibrations at 3C-SiC(001)-(3 2) surfaces

“…To allow a semiconducting surface the Si restlayer is expected to form dimers perpendicular to the adlayer dimers, not shown in Figure 1a. The coverage of the adlayer amounts to 1/3 of a monolayer (ML) what agrees well with experimental observations [5][6][7]. Recent atom-resolved scanning tunneling a e-mail: nienhaus@uni-duisburg.de [8].…”

“…Although extensively studied by various experimental and theoretical methods [3][4][5][6][7][8][9][10][11][12][13], two conflicting models of the geometric structure of 3C-SiC(001)-(3 × 2) surfaces are presently under discussion. Yan et al proposed an alternate dimer-row model sketched in Figure 1a where the Si adlayer and the Si restlayer beneath are shown [4].…”

Optical Anisotropy of theSiC(001)-(3×2)Surface: Evidence for the Two-Adlayer Asymmetric-Dimer Model

“…The b-SiC(001) surface, exhibiting three major surface phases, c(2 3 2), (2 3 1), and (3 3 2), serves as a prototype in that respect. It has been intensively investigated by both experiment [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16] and theory [17][18][19][20][21][22]. Of particular importance are Si-rich conditions, because of the high Si vapor pressure in most methods of growth.…”

Theoretical study of hydrogenated 3C–SiC(0 0 1)-(2 × 1) surface

“…The temperature-induced reversible phase transition between c(4 · 2) and (2 · 1) reconstructions found by high temperature STM observation [5] further supported the AUDD model. This surface is terminated by 1 monolayer (ML) Si atoms in accord with the coverage measurements [1,6,7]. This AUDD reconstruction has also been reproduced by Catellani et al [8] in their ab initio calculations with an applied tensile stress.…”