Geometry dependence of total-dose effects in bulk FinFETs

I. Chatterjee, E. X. Zhang, B. L. Bhuva, R. A. Reed, M. L. Alles, N. N. Mahatme, D. R. Ball, R. D. Schrimpf, D. M. Fleetwood, D. Linten, E. Simoen, J. Mitard, C. Claeys

Research output: Contribution to journalArticle (Academic Journal)peer-review

62 Citations (Scopus)


The total ionizing dose (TID) response of bulk FinFETs is investigated for various geometry variations, such as fin width, channel length, and fin pitch. The buildup of oxide-trapped charge in the shallow trench isolation turns on a parasitic transistor, leading to increased leakage current (higher {{I}-{{\rm OFF}}}) The TID-induced degradation increases with decreasing fin width. Transistors with longer channels degrade less than those with shorter channels. Transistors with large fin pitch degrade more, compared to those with narrow fin pitch. TCAD simulations are used to analyze the buildup of trapped charge in the trench isolation oxide and its impact on the increase in leakage current. The strong influence of charge in the STI in narrow-fin transistors induces a parasitic leakage current path between the source and the drain, while in wide-fin devices, for the same amount of trapped charge in the isolation oxide, the subsurface leakage path is less effective.

Original languageEnglish
Article number6971245
Pages (from-to)2951-2958
Number of pages8
JournalIEEE Transactions on Nuclear Science
Issue number6
Publication statusPublished - 1 Dec 2014


  • Buried oxide
  • charge trapping
  • FinFET
  • geometry dependence
  • hole traps
  • isolation oxide
  • subthreshold slope degradation
  • threshold voltage shift
  • total ionizing dose
  • Worst-case bias


Dive into the research topics of 'Geometry dependence of total-dose effects in bulk FinFETs'. Together they form a unique fingerprint.

Cite this