PHYSICAL MODELING OF THE ENHANCED DIFFUSION OF BORON DUE TO ION-IMPLANTATION IN THIN-BASE NPN BIPOLAR-TRANSISTORS

Using the most advanced physical models of diffusion, we have simulated boron diffusion in the context of a low thermal budget technology for thin-base integrated bipolar transistors. We demonstrated that simulation was able to account for the base broadening due to arsenic implantation in a monocrystalline emitter. Moreover, even in polysilicon emitter bipolar transistors, where the effect of the emitter implantation is suppressed, we found that the extrinsic base implantations could still induce a non-negligible base broadening.