SI-GE HETEROJUNCTION BIPOLAR TECHNOLOGY FOR HIGH-SPEED INTEGRATED-CIRCUITS

This review discusses the fundamentals of SiGe epitaxial base heteroju nction bipolar transistor (HBT) technology that have been developed fo r use in analog and mixed-signal applications in the 1-20 GHz range. T he basic principles of operation of the graded base SiGe HBT are revie wed. These principles are then used to explore the design optimization for analog applications. Device results are presented that illustrate some important trade-offs in device design. A discussion of the use o f UHV/CVD for the deposition of the epitaxial base profile is followed by an overview of the integrated process. This process, which has bee n installed on 200 mm wafers in IBM's Advanced Semiconductor Technolog y Center in Hopewell Junction, N.Y., also includes a full range of sup port devices. The process has demonstrated SiGe HBT performance, relia bility, and yield in a CMOS fabrication with the addition of only one tool for UHV/CVD deposition of the epi-base and, with minimal addition al process steps, can be used to fabricate full BiCMOS designs. This p aper concludes with a discussion of high-performance circuits fabricat ed to date, including ECL ring oscillators, power amplifiers, low-nois e amplifiers, voltage-controlled oscillators, and finally a 12-bit DAC that features nearly 3000 SiGe HBT devices demonstrating medium-scale integration.