Investigation of total dose effects in SiGe HBTs under different exposure conditions. (October 2018)

• Record Type: Journal Article
• Authors: Sun, Yabin; Liu, Ziyu; Fu, Jun; Li, Xiaojin; Shi, Yanling
• Is Part Of: Radiation physics and chemistry. Volume 151(2018:Oct.)
• Page Start: 84
• Page End: 89
• Publication Date: 2018-10
• Subjects: SiGe HBT -- Total dose effects -- Ionization damage -- Displacement damage; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2018.05.019
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: This paper presents the total dose effects of gamma ray and swift heavy ion irradiation on silicon-germanium heterojunction bipolar transistors (SiGe HBTs). The direct current (DC) characteristics, such as forward-Gummel, reverse-Gummel and current ideality factors before and after irradiation are analyzed and used to quantify the dose tolerance. Experiment results show that the performance degradation depends on the dose rate and bias condition during gamma ray irradiation. Compared to gamma ray irradiation, more serious base current degradation exists in the transistors exposed to 25 MeV Si ion. The base current in forward- and reverse-Gummel mode are found to show a distinct sensitivity to gamma ray and swift heavy ion irradiation. An increase in emitter current appears in the reverse-Gummel test after heavy ion irradiation. The underlying physical mechanisms are analyzed and investigated in detail. Highlights: Total dose effects induced by gamma rays and heavy ions are investigated in SiGe HBT. Dependences of dose rates and bias conditions on gamma rays radiation are studied. Serious base current degradation appears in the case of swift heavy ions irradiation. Forward and reversed IB shows various sensitivity to the two radiation sources. The influences of special device structure on base current degradation are analyzed.