利用泊松方程和连续性方程对Al2O3/GaSb p-MOSFET进行二维数值分析,研究其在高场和载流子速度饱和下的电学特性以及漏极电流的开关电流比.与实验研究相对比,沟道长度为0.75 μm的GaSb p-MOS器件获得漏极电流最大为61.2mA/mm.改变沟道长度和GaSb衬底的掺杂浓度,由于高k介质栅电容效应和低阈值电压,漏极电流变化不大.在理想条件下,该器件获得超过三个数量级的漏极开关电流比以及较低的夹断漏电流(10-15A/μm).结果表明,基于高k介质的GaSb MOSFET是III-V族p沟道器件良好的候选材料.

To study the high-field electrical property and the drain current Ion/Ioff ratio of Al2O3/GaSb p-MOSFET, the Poisson and continuity equations with carrier velocity saturation were solved consistently with two-dimensional numerical analysis. The simulation results show that a maximum drain current of 61.2 mA/mm has been reached for 0.75-μm-gate-length GaSb p-MOSFET device. The results have been compared with that of experiment. With change of the channel length and doping-level in substrate GaSb, the drain currents exhibit little change due to the effects of gate capacitance with high-k dielectric and low-threshold voltage. In addition, a high Ion/Ioff ratio with more than three orders of magnitude and relatively low pinch-off leakage current Ioff with 10-15 A/μm are predicted in an ideal condition. The results indicate that GaSb-based MOSFET with high-k dielectric is promising for future p-channel III-V device.