Abstract: A Bi-CMOS device comprises a first insulating layer formed on a principal surface of a semiconductor substrate to extend outwardly from an edge portion of a base region of a bipolar transistor and from an edge portion of each source/drain region of each MOS transistor. A first polycrystalline semiconductor layer is formed on and in contact with a surface area of the base region of the bipolar transistor and a surface area of each source/drain region of each MOS transistor so as to extend on the first insulating layer. A second insulating layer is formed to cover the first polycrystalline semiconductor layer, a base-emitter junction exposed at the principal surface of the substrate and a portion of each of the base region and the emitter region adjacent to the exposed base-emitter junction. The second insulating layer also covers an inside edge of each source/drain region of the MOS transistors, and portions of each source/drain region and a channel region adjacent to the inside edge.

Abstract: A Bi-CMOS device comprises a first insulating layer formed on a principal surface of a semiconductor substrate to extend outwardly from an edge portion of a base region of a bipolar transistor and from an edge portion of each source/drain region of each MOS transistor. A first polycrystalline semiconductor layer is formed on and in contact with a surface area of the base region of the bipolar transistor and a surface area of each source/drain region of each MOS transistor so as to extend on the first insulating layer. A second insulating layer is formed to cover the first polycrystalline semiconductor layer, a base-emitter junction exposed at the principal surface of the substrate and a portion of each of the base region and the emitter region adjacent to the exposed base-emitter junction. The second insulating layer also covers an inside edge of each source/drain region of the MOS transistors, and portions of each source/drain region and a channel region adjacent to the inside edge.

Abstract: A method of producing an integrated circuit device having a bipolar transistor and P-channel and N-channel MOS transistors (Bi-CMOS IC) is disclosed. This method includes the steps of forming a collector contact hole, depositing a polycrystalline silicon layer after formation of the collector contact hole, and diffusing impurities through the polycrystalline silicon layer into a collector region through the collector contact hole to form a collector contact region. The polycrystalline silicon layer doped with impurities is employed as a collector electrode and gate electrodes. The impurities in the collector contact region are re-diffused into the collector region by the subsequent heat treatments used in forming an emitter region and source and drain regions of the respective MOS transistors. A Bi-CMOS IC in which the collector resistance of the bipolar transistor is lowered is thereby produced without a great increase in manufacturing steps.