Solid-State Electronics, Vol.56, No.1, 47-55, 2011
Optimization of SiGe bandgap-based circuits for up to 300 degrees C operation
An investigation of the performance and reliability issues associated with operating silicon-germanium (SiGe) devices and circuits at temperatures up to 300 degrees C is presented, along with a new bypass compensation technique for optimizing bandgap reference performance at these extreme temperatures. In addition to the device-level characterization of a SiGe BiCMOS platform, improved circuit design and a device-level collector-substrate leakage suppression technique are shown to improve the viability of SiGe bandgap reference (BGR) circuits on low-cost, bulk Si wafers for high temperature applications. A shunting technique using various transistors to further improve BGR performance above 200 degrees C is presented, and optimized compensation designs predict new performance records for a bulk-silicon based technology across temperatures from -200 degrees C to 300 degrees C. Finally, a closely-related SiGe temperature sensor circuit is characterized for operating environments up to 300 degrees C. (C) 2010 Elsevier Ltd. All rights reserved.
Keywords:Silicon-germanium;BiCMOS;SiGe HBT;High temperatures;Bandgap voltage reference;Temperature sensor