0.1 μm SOI-MOSFET의 적정 채널도핑농도에 관한 시뮬레이션 연구

In submicron MOSFET devices, maintaining the ratio between the channel length (L) and the channel depth (D) to 3:1 or larger is known to be critical in preventing the deleterious short-channel effects. In this study, n-type SOI-MOSFETs with the channel length of 0.1mm and the Si film thickness (channel depth) of 0.033mm (L:D=3:1) were virtually fabricated by using TSUPREM-4 process simulator. To form functioning transistors on such a thin Si film, a protective layer of 0.08mm-thick surface oxide was deposited prior to the source/drain ion implantation, in order to dampen the speed of the incoming As ions. The p-type boron doping concentration of the Si film, where the device channel is formed, was used as the key variable in the process simulation, and the finished devices were electrically tested with Medici device simulator. The results indicate that, for the channel doping concentration of 1.9~2.51018cm-³, the threshold voltage is 0.5~0.7V, and the subthreshold swing, 70~80mV/dec. These value ranges are all quite reasonable and should form a 'magic region' in which the SOI-MOSFETs run optimally.