Interface chemistry modulation and dielectric optimization of TMA-passivated HfDyO_x/Ge gate stacks using doping concentration and thermal treatment

Abstract

In this work, the effects of different Dy-doping concentrations and annealing temperatures on the interfacial chemistry and electrical properties of TMA-passivated HfDyOx/Ge gate stacks have been investigated systematically.

Revisiting the Chemical Stability of Germanium Selenide (GeSe) and the Origin of its Photocatalytic Efficiency

“…To investigate surface chemical reactivity of a defective GeSe surface, we introduced Se vacancies by sputtering the surface with Ar ions, so as to modify the stoichiometric GeSe sample into a GeSe 0.6 surface (in which also a minor component of Ge 2 Se 3 is present). The emergence of a component at BE = 29.5 eV in Ge 3d is consistent with the presence of metallic Ge on the surface, [ 28b,32 ] as expected after the creation of Se vacancies in GeSe 0.6 . The evolution of core levels in GeSe 0.6 during the exposure to 1 mbar O 2 in the NAP‐XPS apparatus shows that the intensity of GeSe x components slightly increases (up to ≈20%), metallic Ge decreases, and that new features are ascribed to Ge 2 O 3 and GeO 2 [ 28 ] (≈4% of Ge 3d spectrum area) emerge (Figure 4c,d).…”

“…The emergence of a component at BE = 29.5 eV in Ge 3d is consistent with the presence of metallic Ge on the surface, [ 28b,32 ] as expected after the creation of Se vacancies in GeSe 0.6 . The evolution of core levels in GeSe 0.6 during the exposure to 1 mbar O 2 in the NAP‐XPS apparatus shows that the intensity of GeSe x components slightly increases (up to ≈20%), metallic Ge decreases, and that new features are ascribed to Ge 2 O 3 and GeO 2 [ 28 ] (≈4% of Ge 3d spectrum area) emerge (Figure 4c,d). A comparison between pristine and defective GeSe core levels, both measured in the same NAP experimental conditions, clearly confirm that the defective GeSe sample is more prone to oxidation in comparison to the defect‐free GeSe surface, in agreement with our theoretical predictions (Table 1).…”

“…The Ge 3d core level (Figure 3a) of O 2 ‐exposed sample shows, besides the GeSe x (≈27% Ge 3d and ≈34% Se3d spectra area) and Ge 2 Se 3 ‐GeSeO x (≈17% Ge 3d and ≈21% Se 3d spectral area) components, additional features located at BEs of 30.9, 31.4, and 32.4 eV, which can be identified with Ge oxides having different oxidation states: GeO (Ge 2+ , ≈7%), Ge 3 O 4 (Ge 2+ /Ge 3+ , ≈10%), and Ge 2 O 3 (Ge 3+ , ≈3%), respectively. [ 28 ] The peaks corresponding to a higher oxidation state progressively grow up with increasing O 2 doses (Figure S7c,d, Supporting Information), consuming GeSe. The thickness of the mixed phase of different Ge oxides after a dose of 10 6 L O 2 was estimated to be ≈(0.4±0.1) nm through quantitative XPS methods, described in Section S4, Supporting Information.…”

Formation and characterization of holmium oxide on germanium‐based metal‐oxide‐semiconductor capacitor

“…Hence, it is predicted that GeO 2 and Ge 3 N 4 become more stoichiometric for 10 and 15 minutes samples due to the reduction of sub‐stoichiometric unstable phases of GeO x and GeO. It is believed that the content of Ge 2+ (GeO) and Ge 4+ (GeO 2 ) are more thermally unstable than those of Ge 1+ (Ge 2 O) and Ge 3+ (Ge 2 O 3 ) 53,54 . Consequently, the presence of a large amount Ge 2+ (GeO) and Ge 4+ (GeO 2 ) will cause sharp degradation on the thermodynamic stability of the gate stack.…”

Lithium Argyrodite Sulfide Electrolytes with High Ionic Conductivity and Air Stability for All-Solid-State Li-Ion Batteries

“…In addition, the XPS spectrum of the precursor GeS 2 for Ge 3d was compared with that of Li 6+ x Sb 1– x Ge x S 5 I ( x = 0.5 and 0.75), as shown in Figure S7. The XPS spectrum of GeS 2 in Figure S7a indicates the coexistence of Ge 2+ (29.8 eV, blue) and Ge 4+ (31.8 eV, green), while the Ge 4+ state was dominant (72%). − The chemical state of Ge was changed during the synthesis process, forming GeS 4 4– at 30.9 eV in Li 6+ x Sb 1– x Ge x S 5 I, suggesting substitution of Ge into the SbS 4 3– tetrahedra.…”