Patent ID: 6225181
Filing Date: 2001-05-01
Classification: H01L

Abstract:
A process for forming a bipolar device comprising the steps of:performing an isolation implant of dopant of a first conductivity type into a semiconductor substrate to form an isolation layer;thermally driving the isolation implanted dopant into the substrate;performing a first masked buried layer implant of dopant of the first conductivity type into the semiconductor substrate to form a first buried layer;performing a second masked buried layer implant of dopant of the second conductivity type into the semiconductor substrate outside of the first buried layer to form a second buried layer;creating additional lightly doped semiconductor material of the first conductivity type on top of the substrate;forming a first sinker of the first conductivity type extending from a surface of the additional semiconductor material to the isolation layer;forming a second sinker of the second conductivity type extending from the surface of the additional semiconductor material to the second buried layer;performing a first well implant of dopant of the second conductivity type into the additional semiconductor material above the second buried layer to form a first well, the first well including the second sinker;forming a base region of the first conductivity type within the first well; andforming an emitter of the second conductivity type within the base region.