Two approaches involving phosphorus- and arsenic-doped poly emitters for bipolar device optimization in a 1 μm BiCMOS process are reported. An evaluation includes a comparison of process and device parameters for the two emitter types in the context of a junction-isolated process. The impact of device optimization as measured by ECL and BiCMOS ring oscillators and a BiCMOS 256 K SRAM is discussed. Finally, the reliability of phosphorus and arsenic poly emitters, in terms of beta degradation due to reverse biasing of the emitter-base junction, is presented Author(s) Landau, B. Nat. Semicond. Corp., Puyallup, WA, USA Bastani, B. ; Haueisen, D. ; Lahri, R. ; Joshi, S. ; Small, J.