Effects of 3D Channel Shape on the Performance of Nanoscale Gate-All-Around FETs

Recent research on transistors has focused on gate-all-around (GAA) structures, which possess better gate controllability than previous fin field-effect transistor (FinFET) structures. The characteristics of these devices have been optimized through different channel shapes. However, the characteristics of GAA-FETs with channels that have the same cross-sectional area warrant further research. In this study, we simulated n-type GAA-FETs using the Global TCAD Solutions simulation tool to analyze the effective characteristics obtained by setting equal cross-sectional areas. The results show that the total on-current exhibited up to 40.5% enhancement based on shape for the same area. Similarly, under the same conditions, the on/off current ratio exhibited a difference of approximately 1.5 times based on the shape. These findings help determine the optimal shape of the GAA channel and predict the performance when physical limitations restrict the channel shape. Furthermore, they contribute to improving the characteristics of GAA-FETs in mass production.