An ion-implanted N-well bipolar process for university analog integrated circuit fabrication

A five-mask-level, isolated bipolar process was developed. Phosphorous was selectively implanted and annealed into p-type wafers to form the electrically isolated n-wells, and a double diffusion process was used to create active devices inside the n-wells. Several bipolar transistors and simple circuits were successfully fabricated and tested over three developmental processing runs.<
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