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Title: Design of SiGe HBT RF Building Blocks for Extreme Environment Applications
Committee:
Dr. Cressler, Advisor
Dr. Peterson, Chair
Dr. Wang
Abstract: The objective of the proposed research is to design RF circuits optimized for extreme environment operation. Typically, space environment imposes detrimental conditions for normal circuit operation. One of those extreme conditions is the exposure to high-energy heavy-ions. During the collisions with these heavy-ions, the particles travel through the entire silicon volume, causing circuit malfunctions or reliability damages. Mitigating the impact of this single-event effect (SEE) has been a challenging issue for circuit and system designers. Silicon-germanium (SiGe) heterojunction bipolar transistor (HBT) technology has exhibited significant advantages for high frequency millimeter-wave applications since they can provide high unity gain frequency and maximum oscillation frequency than CMOS devices in a similar technology node by optimizing germanium profile and structural configuration. These features are well suitable for high data bandwidth communications systems and imaging systems. However, strategies and techniques for SEE mitigation still need more investigation for their successful use in space-based applications. In this proposal, SiGe HBT-based RF circuits including switches, low-noise amplifiers, and mixers are proposed for SEE mitigation by various radiation-hardening-by-design (RHDB) approaches. SiGe HBT-based RF single-pole single-throw (SPST) switches are proposed and inverse-mode SiGe HBT-based LNAs/mixers are presented in order to reduce transient peaks and durations. TCAD simulation and two-photon absorption experiment results are used to understand and analyze the physical phenomena. In addition, the associated design issues are addressed.