Specific Process Knowledge/Cross Contamination: Difference between revisions
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As explained | As explained on the [[Specific Process Knowledge/Process Flow|'''Process Flow''']] page, there is a large variety of cleanroom fabrication and characterization methods that can be combined to create new materials or structures. Some processes are very sensitive to contaminants and equipment cannot always be cleaned easily running a pre-process cleaning step. | ||
For example, contaminants during a thermal oxidation process to grow silicon dioxide (SiO₂) layers on silicon wafers can significantly degrade the quality and functionality of the resulting oxide layer. Especially metal ions pose a serious issue as they increase leakage currents, reduce the breakdown voltage, reduce the dielectric strength, and cause threshold voltage shifts in MOS devices. But contaminants can also alter the stoichiometry or uniformity of the oxide layer due to non-uniform growth rates and the formation of defective or porous oxides. Therefore, thermal oxidation furnaces have to be maintained extremely clean and the cannot be cleaned easily. | For example, contaminants during a thermal oxidation process to grow silicon dioxide (SiO₂) layers on silicon wafers can significantly degrade the quality and functionality of the resulting oxide layer. Especially metal ions pose a serious issue as they increase leakage currents, reduce the breakdown voltage, reduce the dielectric strength, and cause threshold voltage shifts in MOS devices. But contaminants can also alter the stoichiometry or uniformity of the oxide layer due to non-uniform growth rates and the formation of defective or porous oxides. Therefore, thermal oxidation furnaces have to be maintained extremely clean and the cannot be cleaned easily. | ||