Saddle Fin Structure Effects on the DRAM Access Transistor Performance

Continuous scaling of DRAM chips requires further optimization of saddle fin access transistor performance. This paper presents the TCAD simulation studies of the fin structure effects on the threshold voltage, drivability and subthreshold swing. Fin height simulation results indicate that the increase of fin height can improve the drive current and subthreshold swing. However, the drive current will gradually saturate. Single side gate height simulations also show the similar results. Besides, we found that the device with roundest saddle top has the best performance. These results will help to determine the fin height of new generation devices and provide reference for further scaling and development of saddle fin devices.