Atomic force microscopy observation of layer-by-layer growth of ultrathin silicon dioxide by ozone gas at room temperature

Abstract

Atomic structures on active oxidized silicon films by an ozone gas at room temperature are investigated by an atomic force microscopy. A step-terrace structure similar to that on a clean Si (001) prepared by a silicon homoepitaxy is preserved on the ozone oxidized surface. These atomically regulated structures are also discernible on the SiO2/Si interface when a 1.0-nm-thick SiO2 film oxidized by an atmospheric ozone is removed by a diluted HF etching. It is revealed that the homogeneous lateral oxide growth, i.e., layer-by-layer growth, proceeds at room temperature by an active oxidant such as ozone.

Ultrathin zirconia/SiO2 dielectric stacks grown by ultraviolet–ozone oxidation

“…© 2002 American Institute of Physics. 8 Similar results on the superior electrical properties of UVO-grown SiO 2 have been reported by Nakanishi, Ohkubo, and Tamura. While several materials are being investigated, zirconia is considered to be a potential candidate owing to its high dielectric constant, 1 predicted thermal stability on silicon, 2 and large conduction-band offset with silicon, 3 which helps in reducing leakage current across the dielectric.…”

Stretchable Transparent Electrode via Wettability Self-Assembly in Mechanically Induced Self-Cracking

“…Fluoropolymer, paraffin, or OTS can be used as the coating for the hydrophobic layer on PDMS, as shown in step II. Thus, once defects appear in the brittle layer, it will cause the breakage of the polymer molecular chain in the polymer substrate and expand to the crevice channel since the brittle layer and the substrate are bonded together . In step III, the biaxial stretching process induces the expansion of defects to form crevice channels on PDMS, as shown by the top-view SEM (Figure e).…”

“…Thus, once defects appear in the brittle layer, it will cause the breakage of the polymer molecular chain in the polymer substrate and expand to the crevice channel since the brittle layer and the substrate are bonded together. 32 In step III, the biaxial stretching process induces the expansion of defects to form crevice channels on PDMS, as shown by the topview SEM (Figure 1e). The short-time UV−ozone treatment turns the hydrophobic crevice channel into a hydrophilic one (as shown in step IV of Figure 1a), yet the hydrophobic layer (fluoropolymer, paraffin, and OTS) retains relative hydrophobicity (Figure 1h).…”

“…On the other hand, hydrophobic layers are prepared using hydrophobic polymer films or hydrophobic ends of molecular layers. For example, a brittle layer growing in situ on the surface of the elastomer while being subjected to UV–ozone treatment for a long period of time results in the formation of countless defects inside the layer, which will spread into crazes and finally lead to larger cracks under tension due to the strong bonding of the oxidized layer with the elastomer . Theoretically, there are three pure fracture modes which depend on the direction of the applied load: (1) opening (tensile), (2) sliding (in-plane shear), and (3) tearing (out-of-plane shear) .…”

Growth of epitaxially oriented Ag nanoislands on air-oxidized Si(111)-(7×7) surfaces: Influence of short-range order on the substrate

“…Investigations regarding the oxidation process on H-terminated Si(001) surfaces show a 0.5 nm thick oxide layer growth on the surface at RT after keeping the sample for one day in air where the step-terrace structure was found to be preserved even after the oxidation [28]. However, clean surfaces, when exposed to air, undergoes the oxidation process comparatively rapidly (with a sticking coefficient of 10 −4 -10 −1 ) [29].…”