Bandgap Engineering and Scaling Approaches to SiGe HBT Optimization for Mobile and Optical Networking IC's

Auburn University, Auburn AL

Investigators

Abstract

0112923 Niu Driven by both consumer and commercial needs, the Internet is becoming mobile and broadband, thus allowing the user high speed access to the world wide web from their cell phones and other wireless devices. Optical networking and mobile communication are the key enabling technologies for a mobile and broad-band Internet. Because of its high performance, low cost, and compatibility with silicon CMOS, SiGe HBT technology has recently emerged as a contender for both mobile and optical networking applications. Current SiGe HBTs designs are focused on improving the speed of these devices, while our recent experiments have shown that the optimum device structure for wireless applications are considerably different. Issues important for mobile and optical networking, such as 1/f noise, phase noise (frequency domain sideband and time domain jitter), and linearity, have not been researched as a function of the device structure, or optimized for these performance targets. This ITR proposal is aimed at systematically examining the impact of bandgap engineering and scaling on all of the device figures-of-merit that are of interest to wireless and optical communication IC's, and use of these results to optimize the SiGe profiles and geometries for various circuit applications. In the process, scientifically intriguing and technologically important questions, such as why SiGe HBTs with a nonlinear I-V can have excellent linearity, will be answered. This is a brand new area of SiGe device research, and has a high potential payoff given the exploding industry interest in applying SiGe technology to wireless and optical networking systems. The outcome will include a scientific understanding of important open questions on SiGe HBTs, a modification of the design approach and methodology, as well as hardware demonstration of the novel SiGe profiles through our close collaboration with IBM, thus ensuring a timely impact on current and future development in SiGe technology. Given the enormous amount of interest in applying SiGe technology to both wireless and optical networking applications, the PIs will develop an advanced course on SiGe HBTs using WebCT, so that the outcome of the proposed research can be remotely accessed by graduate students and practicing engineers in industry.