Selective epitaxial growth silicon bipolar transistors for material characterization

Abstract

In development of the epitaxial lateral overgrowth (ELO) bipolar transistor, devices were fabricated in silicon selective epitaxial growth (SEG). These devices were used to electrically characterize the quality of the SEG material. Three silicon bipolar transistors, with almost identical doping profiles and geometries were simultaneously fabricated on the same wafer and their electrical characteristics compared. The three transistors were located in the substrate, a single SEG layer, and a double (interrupted growth) SEG layer. The SEG silicon was grown in a reduced-pressure RF-heated pancake-type epitaxial reactor at 950 degrees C and 150 torr. The transistors were tested for junction ideality factors, junction reverse-bias leakage currents, and forward DC current gain. Test results indicated the excellent device quality of the SEG material relative to the substrate. >