ゲートオールアラウンドナノシート電界効果トランジスタにおける寄生ボトムチャネル制御改善のためのリモートプラズマ選択的シリコンエッチングによるチューナブルサブフィンプロセスの実現

The parasitic Sub-Fin, beneath the stacked nanosheet FETs, limits both leakage and heat dissipation, acting as the bottleneck for improving the performance of NS-FETs. A Sub-Fin edit technology based on remote plasma etching is proposed to modulate the formation of the Sub-Fin. By controlling the process parameters, the Sub-Fin profile can be continuously modulated from "arrow-shaped" to "bell-shaped," which provides the flexibility to improve the thermal resistance and reduce the parasitic Sub-Fin-induced degradation, making it suitable for low-power and high-performance applications, respectively. The Sub-Fin edit technology is fully compatible with mature Gate-All-Around (GAA) fabrication processes and offers a feasible approach to balancing the trade-off between Sub-Fin degradation and heat dissipation through the Sub-Fin.