Abstract: Selective and non-selective epitaxial growth is utilized to form a bipolar transistor having self-aligned emitter and base regions. A substrate of semiconductor material of a first conductivity type is provided and a first layer of semiconductor material of a second conductivity type is non-selectively epitaxially grown on the substrate. An insulating element is formed on a portion of the first layer of semiconductor material and a second layer of semiconductor material of the second conductivity type is selectively epitaxially grown on the first layer such that a portion of the second layer laterally overgrows onto an upper surface of the insulating element. The lateral overgrowth forms an aperture in the second layer to expose a region of the upper surface of insulating element. A layer of insulating material is formed on the second layer to isolate the second layer of semiconductor material from a subsequent deposition of conductive material.