Unprecedented Uniform 3D Growth Integration of 10-Layer Stacked Si Nanowires on Tightly Confined Sidewall Grooves

Bottom-up catalytic growth offers a high-yield, versatile, and powerful tool for the construction of versatile 3D nanocomplexes, while the major challenge is to achieve a precise location and uniformity control, as guaranteed by top-down lithography. Here, an unprecedented uniform and reliable growth integration of 10-layer stacked Si nanowires (SiNWs) has been accomplished, for the very first time, via a new groove-confined and tailored catalyst formation and guided growth upon the truncated sidewall of SiO₂/SiN multilayers. The SiNW array accomplishes a narrow diameter of D_nw = 28 ± 2.4 nm, NW-to-NW spacing of t_sp = 40 nm, and extremely stable growth over L_nw > 50 μm and bending locations, which can compete with or even outperform the state-of-the-art top-down lithography and etching approaches, in terms of stacking number, channel uniformity at different levels, fabrication cost, and efficiency. These results provide a solid basis to establish a new 3D integration approach to batch-manufacture various advanced electronic and sensor applications.