Grooved gate structure Metal-Oxide-Semiconductor (MOS) device is considered as the most promising candidate used in deep and super-deep sub-micron region, for it can suppress hot carrier effect and short channel effect deeply. Based on the hydrodynamic energy transport model, using two-dimensional device simulator Medici, the relation between structure parameters and hot carrier effect immunity for deep-sub-micron N-channel MOSFET’s is studied and compared with that of counterpart conventional planar device in this paper. The examined structure parameters include negative junction depth, concave corner and effective channel length. Simulation results show that grooved gate device can suppress hot carrier effect deeply even in deep sub-micron region. The studies also indicate that hot carrier effect is strongly influenced by the concave corner and channel length for grooved gate device. With the increase of concave corner, the hot carrier effect in grooved gate MOSFET decreases sharply, and with the redu Grooved gate structure Metal-Oxide-Semiconductor (MOS) device is considered as the most promising candidate used in deep and super-deep sub-micron region, for it can suppress hot carrier effect and short channel effect deeply. Based on the hydrodynamic energy transport model, using two-dimensional device simulator Medici, the relation between structure parameters and hot carrier effect immunity for deep-sub-micron N-channel MOSFETs is studied and compared with that of the conventional conventional planar device in this paper. Negative junction depth, concave corner and effective channel length. Simulation results show that grooved gate device can suppress hot carrier effect deeply even in deep sub-micron region. The studies also indicate that hot carrier effect is strongly influenced by the concave corner and channel length With the increase of concave corner, the hot carrier effect in grooved gate device and with the redu