High-speed fully self-aligned single-crystal contacted silicon bipolar transistor

A novel high-speed self-aligned npn bipolar transistor fabrication process is presented. Base contacts are formed by epitaxial lateral overgrowth of single-crystal silicon on silicon-dioxide. Impurity-enhanced oxidation of silicon is used to achieve self-alignment of the emitter. Ultra-low resistance p-type base contacts have been fabricated with measured sheet resistances of 19 Omega / Square Operator .