Specific Process Knowledge/Thermal Process/Oxide mask

Oxide mask thickness

A thermal oxide mask can protect areas from diffusion during a pre deposition and drive-in process. It can also be used during a PECVD based diffusion process. The required oxide thickness differs for phosphorous and boron diffusion as the respective diffusion coefficients are different. The figures below indicate the minimum thermal oxide thickness to be used based on temperature and diffusion time.

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