Strong Temperature Dependence of the Initial Oxide Growth on the Si(111)7 × 7 Surface

Abstract

Temperature dependence of oxide growth kinetics on the Si(111)7×7 surface has been investigated by ultraviolet photoelectron spectroscopy. The amount of adsorbed oxygen on the Si surface during oxidation can be obtained from the O 2p spectra, which showed that the amount of oxygen increased with temperature below 600 • C. It was found that the results cannot be described by the dual-oxide-species model for Langmuir-type adsorption in which adsorbed oxygen hardly moves on the surface. Therefore, we propose a new reaction model in which the migration and agglomeration of metastable oxygen on the surface should be considered. By studying the results of work function, we concluded that more adsorbed oxygen on the surface may incorporate into the back bond and a larger amount of defects can be generated at the Si/SiO2 interface at higher temperature.

Relation Between Oxidation Rate and Oxidation-Induced Strain at SiO2/Si(001) Interfaces during Thermal Oxidation

“…O 2 molecules adsorb on the Si surface and react with Si atoms with the dangling bond, and then the area of the reaction site decreases with increasing oxide coverage. Therefore, the surface oxidation proceeds by Langmuir-type adsorption, and the oxygen uptake curve is interpreted by the equation 5,12,22,23)…”

Self‐accelerating oxidation on Si(111)7 × 7 surfaces studied by real‐time photoelectron spectroscopy

“…The O 1s intensities I O1s at RT and 550 °C shown in Figs (a) and (b) were obtained from the O 1s spectra by subtracting the background with a straight line. The O 1s intensities were fit using Eqn , which is based on a modified Langmuir‐type adsorption model, in which surface oxidation proceeds by Langmuir‐type adsorption, where A 0 is the amount of oxygen absorbed on the surface, and 1/ τ 0 is the reaction coefficient. According to the modified Langmuir‐type adsorption model, the oxidation of Si(111) surface transitions from surface oxidation to interface oxidation at an O 2 dosage of ~5000 L (1 L = 1.33 × 10 −4 Pa s) at RT and ~9000 L at 550 °C.…”

“…The O 1s intensities I O1s at RT and 550°C shown in Figs 1(a) and (b) were obtained from the O 1s spectra by subtracting the background with a straight line. The O 1s intensities were fit using Eqn (1), which is based on a modified Langmuir-type adsorption model, [16] in which surface oxidation proceeds by Langmuir-type adsorption,…”

Mechanism of Crack Propagation during Hot‐Rolling Process of a Medium‐Carbon 40Cr Alloy Steel

“…[1][2][3] Surface defects of a medium-carbon steel in products may occur, the surface microstructure of a mediumcarbon steel products is often strengthened by laser bionic texture to improve fatigue wear resistance of medium-carbon low-alloy steel during actual service. [1,[3][4][5][6][7][8] Furthermore, a larger cross section of blooms and addition of alloy (such as Mn and Cr) are required to satisfy the requirements of high-strength and high-toughness steel, while this increases the higher crack sensitivity during continuous casting and rolling process. [9][10][11][12] In addition, the cracks started forming in surface of blooms during the continuous casting process and the surface cracks often appear severe cracks propagation conditions during hotrolling process.…”