摘要 |
In sophisticated semiconductor devices, the encapsulation of sensitive gate materials, such as a high-k dielectric material and a metal-containing electrode material, which are provided in an early manufacturing stage may be achieved by forming an undercut gate configuration. To this end, a wet chemical etch sequence is applied after the basic patterning of the gate layer stack, wherein at least ozone-based and hydrofluoric acid-based process steps are performed in an alternating manner, thereby achieving a substantially self-limiting removal behavior. |