Dry etching of layer sequence, for anisotropic etching of aluminum-containing substrates, by etching fourth layer in plasma comprising halogen-containing gas, and third layer in plasma comprising halogen- and nitrogen-containing gases

摘要

The method involves applying a mask to a fourth layer, and etching the non-masked regions of the fourth layer in a first plasma (P1), mainly comprising halogen-containing gas. The third layer is etched in a second plasma (P2), mainly comprising halogen-containing and nitrogen-containing gases. The second layer is etched in a third plasm (P1), which is preferably the same as the first plasma.