The effect of emitter sidewall isolation on the emitter junction in a double layer polysilicon bipolar process

摘要

The 2D equi-concentration dopant contours are revealed for the first time for a cross-section through a 1 mu m double-layer polysilicon bipolar device. The planarity of the emitter junction is shown to be dependent on the presence of emitter sidewall spacer filters. Implications for ultrashallow junction devices are presented.