A comprehensive understanding of the efficacy of N-Ring hardening methodologies in SiGe HBTs.

Conference · Sat May 01 04:00:00 EDT 2010

OSTI ID:1013798

Phillips, Stanley D; Dodd, Paul Emerson; Cressler, John D; Vizkelethy, Gyorgy; Najafizadeh, Laleh; Diestelhorst, Ryan; Moen, Kurt A; Sutton, Akil K

We investigate the efficacy of mitigating radiation-based single event effects (SEE) within circuits incorporating SiGe heterojunction bipolar transistors (HBTs) built with an N-Ring, a transistor-level layout-based radiation hardened by design (RHBD) technique. Previous work of single-device ion-beam induced charge collection (IBICC) studies has demonstrated significant reductions in peak collector charge collection and sensitive area for charge collection; however, few circuit studies using this technique have been performed. Transient studies performed with Sandia National Laboratory's (SNL) 36 MeV 16O microbeam on voltage references built with N-Ring SiGe HBTs have shown mixed results, with reductions in the number of large voltage disruptions in addition to new sensitive areas of low-level output voltage disturbances. Similar discrepancies between device-level IBICC results and circuit measurements are found for the case of digital shift registers implemented with N-Ring SiGe HBTs irradiated in a broadbeam environment at Texas A&M's Cyclotron Institute. The error cross-section curve of the N-Ring based register is found to be larger at larger ion LETs than the standard SiGe register, which is clearly counter-intuitive. We have worked to resolve the discrepancy between the measured circuit results and the device-level IBICC measurements, by re-measuring single-device N-Ring SiGe HBTs using a time-resolved ion beam induced charge (TRIBIC) set-up that allows direct capture of nodal transients. Coupling these measurements with full 3-D TCAD simulations provides complete insight into the origin of transient currents in an N-Ring SiGe HBT. The detailed structure of these transients and their bias dependencies are discussed, together with the ramifications for the design of space-borne analog and digital circuits using SiGe HBTs.

• Research Organization: Sandia National Laboratories
• Sponsoring Organization: USDOE
• DOE Contract Number: AC04-94AL85000
• OSTI ID: 1013798
• Report Number(s): SAND2010-3155C
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
46 INSTRUMENTATION RELATED TO NUCLEAR SCIENCE AND TECHNOLOGY
CHARGE COLLECTION
DESIGN
DIGITAL CIRCUITS
GERMANIUM SILICIDES
HETEROJUNCTIONS
ION BEAMS
RADIATION EFFECTS
RADIATION HARDENING
TRANSISTORS