Silicon oxidation transport

O. Najmi, I. Montero, L. Galan, and J. M. Albella, Study of the silicon oxide transportation during the breakdown process. Mater. Sci. Forum. 185-188, 535, 1995. 

B. Agius, M. Froment, and S. R. Rochet, Oxygen transport studied by labeling in thin thermal silicon oxide films in connection with their structural characteristics, in Passivity of Metals and Semiconductors, M. Froment (ed.), p. 453, Elsevier, Amsterdam, 1983. 

Pentacene is attracting considerable attention as its charge transport properties are excellent [4, 48], and films of pentacene on silicon oxide are commonly used for thin film transistors in which the silicon oxide serves as gate dielectric. 

From a resource utilization viewpoint this seems to be an ecologically excellent development, as silicon oxide is the most available mineral on Earth. Industrial processes needed to process minerals into useable products do, however, create wastes and consume energy. Sustainable production means that no aspects of human life should be threatened by this processing and that its products should improve living conditions on Earth. The Bmndtland Commission states that sustainable development must be based on availability of metals and materials for use in building, construction, transportation, tools, and necessary equipment. 

The oxidation of silicon has been studied extensively due to the need for formation of dielectric silica layers on silicon by thermal oxidation for semiconductor devices. Deal and Grove (1965) have written a classic paper on this subject in which gas phase diffusion rates, linear reaction rates of oxygen with silicon, as well as oxygen transport rates through the growing silica scale are all considered. It was found that silicon oxidation can be described by a linear parabolic rate law ... 

Another problem in the construction of tlrese devices, is that materials which do not play a direct part in the operation of the microchip must be introduced to ensure electrical contact between the elecuonic components, and to reduce the possibility of chemical interactions between the device components. The introduction of such materials usually requires an annealing phase in the construction of die device at a temperature as high as 600 K. As a result it is also most probable, especially in the case of the aluminium-silicon interface, that thin films of oxide exist between the various deposited films. Such a layer will act as a banier to inter-diffusion between the layers, and the transport of atoms from one layer to the next will be less than would be indicated by the chemical potential driving force. At pinholes in the AI2O3 layer, aluminium metal can reduce SiOa at isolated spots, and form the pits into the silicon which were observed in early devices. The introduction of a tlrin layer of platinum silicide between the silicon and aluminium layers reduces the pit formation. However, aluminium has a strong affinity for platinum, and so a layer of clrromium is placed between the silicide and aluminium to reduce the invasive interaction of aluminium. 

Group 3 Nitrate/metal compositions without sulphur Compositions with <35-65% chlorate Compositions with black powder Lead oxide/silicon with >60% lead oxides Perchlorate/metal Burn fast Large firework shells Fuse protected signal flares Pressed report cartridges in primary packagings Quickmatches in transport packagings Waterfalls Silver wheels Volcanoes Black powder delays Burn very violently with single-item explosions... 

---