LOCOS with Sacrificial Poly-Silicon

Here is a comparison of the LOCOS process with and without some sacrificial poly-Si:
LOCOS with sacrificial poly-Si layer
Provided, some of the oxide is removed by an "etch-back" process, the lateral extension can be kept somewhat smaller than in the conventional case.
While this makes things quite complicated, the final versions of the LOCOS process were even more complicated.

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go to 6.2.2 LOCOS Process

© H. Föll (Electronic Materials - Script)