STUDY ON THE RELATION BETWEEN STRUCTURE AND HOT CARRIER EFFECT IMMUNITY FOR DEEP SUB-MICRON GROOVED GATE NMOSFET''''s

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     

DEMOS在热载流子应力下的混合失效模式

研究了18V漏极延伸金属氧化物半导体场效应晶体管(DEMOS)在高栅极电压下的热载流子注入效应。实验观察到两种失效模式,分别是热空穴的注入效应和高栅压导致的阈值电压增大,发现其对器件损伤分别局限在漏极区域和沟道区域,对器件的性能影响正好相反,前者减少了漏极串联电阻,而后者增大了沟道电阻。描述了这两个失效模式的物理过程,分析并讨论了器件参数的退化曲线。讨论了如何提高DEMOS在高栅压下的抗热载流子的能力,指出了漏极上方的氧化层的质量和栅极氧化层中自由电荷数量,对于提高器件的可靠性至关重要。