Degradation Analysis of Lateral PNP Transistors Exposed to X-Ray Irradiation

Author

Kato, Masataka ; Nakamura, Tohru ; Toyabe, Toru ; Okabe, Takahiro ; Nagata, Minoru

Author_Institution

Central Research Laboratory, Hitachi Ltd., Kokubunji, Tokyo 185 Japan 0423-23-1111

Volume

31

Issue

6

fYear

1984

Firstpage

1513

Lastpage

1517

Abstract

Degraded current gain by X-ray irradiation is analyzed for lateral pnp transistors. The relationship between the total dose of X-ray and the surface recombination velocity is also studied. Surface recombination velocity is evaluated in two regions: the depletion region of the emitter-base junction and the non-depleted charge-neutral region of the base surface. X-ray total dose dependency of surface recombination velocity is experimentally derived as: sdep = 0.33D0.9 for depletion regions, and sSur = 3.8D0.8 for non-depleted surface region in the device structure. A radiation hardened structure with a surface potential barrier for lateral pnp transistors is proposed. The possibility of more than one-order of magnitude improvement in radiation hardness is demonstrated by both simulation and experiments.

Keywords

Bipolar transistors; Degradation; Density measurement; Diodes; Interface states; Ionizing radiation; Laboratories; Radiation hardening; Velocity measurement; Voltage;

fLanguage

English

Journal_Title

Nuclear Science, IEEE Transactions on

Publisher

ieee

ISSN

0018-9499

Type

jour

DOI

10.1109/TNS.1984.4333540

Filename

4333540