This combined for the manufacture of bipolar transistors with oxide vertical insulated with respect to the bipolar transistors lateral information insulated with respect with oxide and structures thus manufactured

摘要

A process for fabricating oxide-isolated vertical bipolar transistors and complementary oxide-isolated lateral bipolar transistors incorporates the steps of growing a doped epitaxial layer of single- crystal silicon on a silicon substrate, applying a first insulation material in a selected pattern over the epitaxial layer to define oxide- isolation regions and device regions, etching grooves in the areas in which oxide-isolation regions will be formed, applying a self-aligned base insulation material over those portions of the interface between the first insulation material and the grooves which bound the region between the base of any vertical bipolar transistor to be formed and the emitter of any lateral bipolar transistor to be formed, applying an impurity of a conductivity type opposite to the conductivity type of the epitaxial layer to those groove areas not covered by the self-aligned base insulation material, the impurity serving to prevent emitter-to-collector inversion along the wall of the base of any vertical bipolar transistor without shorting the emitter and collector of any lateral bipolar transistor, forming oxide- isolation regions in the grooves and forming the vertical bipolar transistors and the lateral bipolar transistors in the device regions. The process of the present invention will produce discrete lateral bipolar transistors, discrete vertical bipolar transistors capable of operation in the conventional mode or in the inverse mode, or a composite structure which merges both a vertical bipolar transistor and a lateral bipolar transistor together on the same silicon island to form an injection-logic gate in which the base of the vertical bipolar transistor serves as the collector of the lateral bipolar transistor, the vertical transistor being operated in the inverse mode.