In this study, the super-steep retrograde N-channel doping profile was found to degrade the gate oxide integrity (GOI), hot carrier lifetime and the ESD performance. Therefore, a simple method was proposed to from the conventional -channel doping profile without adding the masking step. In addition, to improve the oxide/Si interface quality, a modified LDD structure with As and P31 co-implant followed by gate re-oxidation was also proposed to improve the hot carrier lifetime. To improve the ESD failure threshold, after the real-time I-V characteristics measurement during ESD zapping event and detail failure analysis, a modified multi-finger protection structure with P+ diffusion into source regions was also proposed to relieve the current crowding effect. Moreover, for reducing the snapback voltage, a P- type dopant was proposed to implant into the drain region of the ESD transistor.
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