To further improve the performance of highly stacked GeSi channels, the 6 stacked GeSi nanowires without parasitic channel are demonstrated by optimizing the wet etching. The device has the SS of 80mV/dec and ION/IOFF of 1.5E5. The ION per stack of 120μA and ION per footprint of 4600μA/μm are achieved at VOV=VDS=0.5V among Ge/GeSi 3D nFETs. The results have been published in 2022 VLSI-TSA, and won the Best Student Paper Award. Increasing the number of stacked channels is needed to further enhance the transistor ION. The 10 stacked GeSi nanowires without parasitic channel are demonstrated with the ION per stack of 140μA (6500μA/μm), and the results have been published in 2022 SISC. The 16 stacked GeSi nanowires are demonstrated with the ION per stack of 190μA (9400μA/μm) by the co-optimization of CVD epitaxy and isotropic wet etching, and the results have been submitted to Nature communications engineering.