Bipolar transistor design for low process-temperature 0.5 mu m Bi-CMOS

A low-temperature (800-850 degrees C) processes bipolar transistor design suitable for high-performance 0.5- mu m BiCMOS process is discussed. It was found that insufficient activation of arsenic in the emitter, fast base boron diffusion in the low-concentration region caused by implantation damages for the direct-ion-implanted emitter case, and insufficient arsenic diffusion from the poly-Si for the poly-Si emitter case should be considered as serious problems when the low-temperature furnace anneal is used. High-temperature RTA (rapid thermal annealing) is shown to solve those problems. Based on the impurity diffusion behaviors and related electric bipolar characteristics, the optimum conditions and structures for bipolar transistor design for the high-performance 0.5- mu m BiCMOS process are discussed.<
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