Specific Process Knowledge/Cross Contamination: Difference between revisions
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= Cross Contamination = | = Cross Contamination = | ||
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. | ||
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|Please note, as a multiuser facility we need to establish working procedures to provide the best possible working environment for all our users, not only in terms of safety, but also regarding reliability of equipment and processes. '''We expect all users to adhere strictly to the guidelines and equipment usage rules, with particular attention to preventing cross-contamination between tools.''' We are happy to assist you in reviewing and refining your process flow to help streamline your work and ensure compatibility with our facility standards. You can find more information on how to create a process flow [[ | |Please note, as a multiuser facility we need to establish working procedures to provide the best possible working environment for all our users, not only in terms of safety, but also regarding reliability of equipment and processes. '''We expect all users to adhere strictly to the guidelines and equipment usage rules, with particular attention to preventing cross-contamination between tools.''' We are happy to assist you in reviewing and refining your process flow to help streamline your work and ensure compatibility with our facility standards. You can find more information on how to create a process flow [[Specific Process Knowledge/Process Flow|'''here''']]. | ||
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We have created a cross contamination sheet available in Labmanager as a guideline regarding which materials are allowed to enter an equipment. It is also possible to show the cross contamination between two tools. You can find more information below. | We have created a cross contamination sheet available in Labmanager as a guideline regarding which materials are allowed to enter an equipment. It is also possible to show the cross contamination between two tools. You can find more information below. | ||
Cross contamination can origin from many different sources: the substrate | Cross contamination can origin from many different sources: the substrate itself, films deposited or grown on top of the substrate, traces from previous processes, and the environment. To make it easier for our users, we have sorted them into groups according to the sources of contamination. | ||
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