A first principles study of H₂S adsorption and decomposition on a Ge(100) surface

Abstract

We employed density functional theory (DFT) calculations to examine the adsorption configurations and possible reaction paths for H2S on a Ge(100) surface.

Total Dose Effects and Bias Instabilities of (NH4)2S Passivated Ge MOS Capacitors With Hf<italic>x</italic>Zr1–<italic>x</italic>O<italic>y</italic>Thin Films

“…This can be attributed to the build-up of Ge dangling bonds at Ge/dielectrics interface. It has been reported that the passivation of Ge surface by sulfide can result in Ge-S bonds and thus decrease the interface traps [12,16]. Moreover, it is suggested that H + protons generated at the anode by positive bias can drift to the Ge interface and break the passivated Ge-S bonds as shown in Fig.…”

“…Moreover, it is suggested that H + protons generated at the anode by positive bias can drift to the Ge interface and break the passivated Ge-S bonds as shown in Fig. 5 [12,27,30]. One possible reaction of the formation of an interface trap is shown in (7), Ge -S + 2 H +  Ge + + H2S…”

“…However, a fundamental issue of the application of Ge in CMOS technology is that Ge easily forms unstable oxides GeOx on the surfaces, which can result in a poor quality interface between the Ge channel and high-k dielectrics and low carrier mobility in the channel. This technological issue has been overcome by the passivation of Ge surface, which can prevent oxidation formation during device processing [12][13][14]. It has been reported that sulfur passivation of germanium is very effective in preventing the formation of the GeOx at the interface, which can lead to superior Ge gate stack [15,16].…”

Review of Theoretical and Computational Studies of Bulk and Single Atom Catalysts for H2S Catalytic Conversion

“…On the fcc transition metal (100) surfaces, three high symmetry sites are considered for adsorption of H 2 S: top, bridge, and hollow sites (Figure 4a). On Fe, [98] Cu, [99] Pd, [100] and Au(100) [101] surfaces, molecular H 2 S prefers to adsorb on the top site, while on Ni, [102] Mo, [103] Rh, [104] and Ge(100) [105] surfaces, molecular H 2 S prefers to bind on the bridge site (Table 3). Former theoretical results show that the adsorption energies of molecular H 2 S on 3d metals (Fe, Ni, and Cu(100) surfaces) are in the range of À 0.50 to À 0.76 eV, while the adsorption energies of molecular H 2 S on 4d metals (Mo, Rh, and Pd(100) surfaces) are in the 100) surface with the adsorption energy of À 0.36 eV.…”