Ryan, Mason & Lewis, LLP
Reduction of multi-threshold voltage patterning damage in nanosheet device structure
Devices and methods are provided to fabricate nanosheet field-effect transistor devices having dummy nanosheet channel layers disposed above active nanosheet channel layers to protect the active nanosheet channel layers from oxidation during work function metal patterning processes that are implemented as part of a multi-threshold voltage process module. The dummy nanosheet channel layers have a reduced thickness so that the dummy nanosheet layers do not function as active channel layers of the nanosheet field-effect transistor devices. The dummy nanosheet channel layers serve as oxygen infusion blocking layers to protect the active nanosheet channel layers from being infused with oxygen and oxidized by a directional plasma etch process performed during a work function metal patterning process.
International Business Machines Corporation
B H H H H H H H H H H H H H H H
B82Y H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L H01L
inventional additional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional inventional
Kangguo ChoongHyun Juntao Shogo
Cheng Lee Li Mochizuki