摘要:
Methods for etching a dielectric barrier layer with high selectivity to a dielectric bulk insulating layer are provided. In one embodiment, the method includes providing a substrate having a portion of a dielectric barrier layer exposed through a dielectric bulk insulating layer in a reactor, flowing a gas mixture containing H2 gas, fluorine containing gas, at least an insert gas into the reactor, and etching the exposed portion of the dielectric barrier layer selectively to the dielectric bulk insulating layer.