Characterization, film stages

Thin-Film Stage. The mechanism of thin-film formation is characterized by three simultaneous crystal building processes nucleation (formation), growth, and coalescence of three-dimensional crystallites (TDCs). 

The self-sustaining nature of the process leads to a drastic reduction in the stability of the passive film. Stage HI is characterized by the breakdown of the passive film due to the attainment of what has become known as the critical crevice solution. This solution has a low pH [typically 1 or less (23)] and a high Cl"... 

SIMS Cluster Ion Characterization During Oxygen Adsorption and Oxidation. For heavy oxidation, that is essentially bulk oxide films, the oxidation state of the metal can be determined from the positive and negative SIMS intensity distributions (1 ). Though similar attempts have been made to characterize the nature of the surface during the early stages of oxygen interactions (14,15), we now know from the extensive information available from other techniques that such interpretations are incorrect. We use the by now well-characterized W(100)/O and Ni(100)/0 systems as examples. 

Tremiliosi-Eilho G, Jerkiewicz G, Conway BE. 1992. Characterization and significance of the sequence of stages of oxide film formation at platinum generated by strong anodic polarization. Langmuir 8 658-667. 

As is the case for most natural phenomena, oxide films often have a rapid initiation, a vigorous youthful growth period, a fruitful middle age, a declining later period and, finally, destruction. In this vein, we can list at least ten overlapping stages which may characterize an oxide film at one time or another during its lifetime. 

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