Method for isotropic etching

摘要

According to one embodiment, the invention relates to a method for the anisotropic etching of patterns in at least one layer to be etched through a hard mask comprising carbon in an inductive-coupling plasma etching reactor (ICP), the method being characterized in that the hard mask is made from boron doped with carbon (B:C), and in that, prior to the anisotropic etching of the patterns in said layer to be etched through the hard mask of carbon-doped boron (B:C), the following steps are performed:
realization of an intermediate hard mask situated on a layer of carbon-doped boron intended to form the hard mask made from carbon-doped boron (B:C),etching of the layer of carbon-doped boron (B:C) through the intermediate hard mask in order to form the hard mask made from carbon-doped boron (B:C),

the realization of the intermediate hard mask and the etching of the hard mask made from carbon-doped boron (B:C) being done in said inductive coupling plasma etching reactor (ICP).

主权项

1. A method for anisotropic etching of a pattern in at least one layer to be etched through a hard mask comprising carbon in an inductively-coupled plasma etching reactor, the method comprising:
etching an intermediate layer to obtain an intermediate hard mask situated on a hard mask layer comprising carbon-doped boron, then etching the hard mask layer comprising carbon-doped boron through the intermediate hard mask to form a hard mask comprising carbon-doped boron, and then anisotropically etching the at least one layer to be etched, wherein: the etching of the hard mask layer comprising carbon-doped boron is performed in a plasma comprising chlorine (Cl2), argon (Ar), an oxygen-based gas and a fluorinated gas, and the etching of the intermediate layer and the etching of the hard mask layer comprising carbon-doped boron are both performed in the inductively-coupled plasma etching reactor.