Due to the growing severity of the short-channel effect in semiconductor devices, a new type of device, the FinField-Effect Transistor (FinFET), has been proposed, developed and applied. This paper aims to establish a 15 nm n-type Bulk FinFET device model to investigate the impact of basic structural parameters, device temperature, and gate material on the performance of Bulk FinFETs. Simulations are conducted to analyze the effect of different gate lengths, fin widths, fin heights, channel doping concentration, device operating temperature, and gate materials on the performance of FinFETs. The results show that increasing the gate length, decreasing the fin width, and increasing the fin height can effectively suppress the short-channel effect. Moreover, the channel doping concentration below 1×10¹⁷ cm^-3 has little effect on the device characteristics, while high doping concentration causes device failure. Additionally, increasing the operating temperature leads to device performance degradation. Finally, using high K dielectric material as the gate material is found to enhance device performance compared to using conventional SiO₂ material.