50-nm Nano-Scaled Vertical-Transistor with NiSi₂ Seed-Induced Vertically Crystallized Poly-Silicon Channel for Very-Large-Scale-Integration.

Vertical-channel MOSFETs are hard to demonstrate a high electrical performance than the planar MOSFETs because of its polycrystalline-silicon (poly-Si) channel for 3-D CMOS ICs. In this paper, we have demonstrated a vertical poly-silicon-channel (VPSC) transistor NiSi2 seed-induced vertical crystallization (SIVC) and compared with the typical SG-VPC MOSFETs with solid-phase crystallization (SPC). The SIVC poly-Si showed large longitudinal grains with low defect trap sites, while the SPC poly-Si showed small spherical grains with large defect trap sites. Therefore, the electrical performance of SG-VPC MOSFETs with SIVC was superior to the SG-VPC MOSFETs with SPC in all aspects.