天线效应对LPNP管输出曲线的影响

天线结构是监控半导体工艺过程中等离子体损伤的一种典型结构,一般主要用来监控MOS器件栅氧的损伤。文中,该结构用来监控横向PNP(LPNP)管工艺过程中的发射极结损伤。实验发现,带天线结构的LPNP管的输出曲线容易出现翘曲现象,分析认为该异常不是由于发射极结损伤造成的,因为发射极结工艺过程中并没有受到损伤。同时发现该翘曲现象在LPNP管保护环接低电位时会消失,该低电位在很大范围内变化时,输出曲线基本一致,且输出曲线电流较保护环悬空时的电流整体偏大,在集电极电压较大时,输出电流和保护环悬空时的电流一致。

The Impact of Antenna Effect in Process to Output IV Curve of LPNP Transistor

Antenna structure is the typical method that monitors plasma damage during semiconductor manufacture process. Generally, this structure is used for monitoring MOS transistor gate oxide damage in plasma process. In this paper, the structure is used to monitor the process damage to LPNP transistor emitter junction. Experiment shows that the output IV curve of LPNP transistor with antenna appears kink effect. It is not considered as a result of emitterljunction damage and the process does no damage to the emitter junction. The kink effect will disappear with the guard ring connected with low voltage potential. The guard ring voltage potential varies in wide range, but the output IV curve shows no difference. The current with guard ring connected with low potential is bigger than that with guard ring floating. With the collector voltage increasing, the current is equal to each other.