Selective epitaxy base transistor (SEBT)

A bipolar transistor using selective epitaxy for base formation in a double-poly self-aligned structure is presented. The intrinsic base was formed by a selective-epitaxial deposition in place of ion implantation. Such epitaxial base processes are capable of achieving a narrow intrinsic base sheet resistance R/sub bi/ and base-emitter diffusion capacitance c/sub be/ compared to advanced ion-implanted processes. A selective epitaxial base can be simply introduced in advanced double-poly self-aligned processes compared to a nonselective epitaxial layer.<
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