We report on the top-down fabrication of vertically-stacked polysilicon nanowire (NW) gate-all-around (GAA) field-effect-transistors (FET) by means of Inductively Coupled Plasma (ICP) etching and nanostencil lithography. The nanostencil is used to form sub-μm GAA gates over polysilicon NW array channels with high aspect ratio, considerably simplifying the lithographic steps above regions with deep 3D topography and non-planar surface features. This process lead to fabrication yields larger than 70% and authors envisage even larger yields of ⩾85% with optimized mask design. Electrical measurements confirm the results obtained from similar devices fabricated with a standard lithography method while achieving higher density, larger reproducibility and yield, maintaining the performance improvement related with scaling.
Edoardo Charbon, Claudio Bruschini, Ekin Kizilkan, Pouyan Keshavarzian, Francesco Gramuglia, Myung Jae Lee