US Patent 11699621 Method for patterning a lanthanum containing layer

Embodiments described herein relate to a method for patterning a doping layer, such as a lanthanum containing layer, used to dope a high-k dielectric layer in a gate stack of a FinFET device for threshold voltage tuning. A blocking layer may be formed between the doping layer and a hard mask layer used to pattern the doping layer. In an embodiment, the blocking layer may include or be aluminum oxide (AlO