VVMOS功率晶体管的负阻击穿

VVMOS晶体管是一种开有V形槽的垂直沟道高频功率MOS场效应器件,它的一个主要优点是与其它MOS器件一样不会发生二次击穿,然而近来一些作者报道MOS器件有负阻击穿效应,而这种负阻击穿效应也会引起二次击穿,导致器件烧毁。我们在测量自制的VVMOS晶体管时,也观察到了负阻击穿,经过研究,提出了纵向寄生npn双极晶体管的VVMOS晶体管负阻击穿模型,在此基础上还提出了几种抑制负阻击穿效应的方法,在采用了这些方法后,负阻击穿效应被减弱,甚至被消除,从而证实了所提出的VVMOS晶体管负阻击穿模型。

THE NEGATIVE RESISTANCE BREAKDOWN EFFECT IN VVMOS POWER TRANSISTOR

VVMOS transistor is a new type of high frequency power MOS transistor with vertical channels at the surface of the V-groove. Like other MOSFET s, one of the important features is no secondary breakdown, However, these is negative resistance breakdown, effect in MOSFET's is reported recently by some authors. The reported effects may eause secondary breakdown, and result in destructive damage to the de-vices.While measuring the VVMOSFET s made in our laboratory, we have also observed the destructive negative resistance breakdown effect. And model based on the effect of parasitic vertical bipolar npn transistor is proposed to explain this effect. Some using these method, the negative resistance breakdown effect has been lowered of even eliminated, and thus the proposed negative resistance breakdown model for VVMOSFET's is verified.