The impact of trench geometry and processing on the performance and reliability of low voltage power UMOSFETs

S. A. Suliman, N. Gallogunta, L. Trabzon, Jianhua Hao, G. Dolny, R. Ridley, T. Grebs, J. Benjamin, C. Kocon, J. Zeng, C. M. Knoedler, M. Horn, O. O. Awadelkarim, S. J. Fonash, J. Ruzyllo

Research output: Journal article publicationJournal articleAcademic researchpeer-review

5 Citations (Scopus)

Abstract

We report on the performance and reliability of n-channel U-shaped trench-gate metal-oxide-Si field-effect transistors (n-UMOSFETs). Damage induced on the trench sidewalls from the reactive ion etching of the trench is concealed by post-etch cleaning as witnessed by the independence of the effective electron mobility in the channel of trench geometry. However, charge pumping measurements coupled with electrical stressing of the gate oxide in the Fowler-Nordheim (FN) regime, have shown that the oxide edge adjacent to the drain and the oxide/silicon interface therein are the most susceptible regions to damage in the n-UMOSFET. Using scanning electron microscopy this is shown to result from gate-oxide growth non-uniformity that is more pronounced at the trench bottom corners where the oxide tends to be thinnest. We also report on the n-UMOSFET's performance and hot electron stress reliability as functions of the p-well doping.
Original languageEnglish
Pages (from-to)308-314
Number of pages7
JournalAnnual Proceedings - Reliability Physics (Symposium)
DOIs
Publication statusPublished - 1 Jan 2001
Externally publishedYes

Keywords

  • Channel doping
  • Charge pumping
  • Fowler-Nordheim stress
  • Gate-oxide growth
  • Hot-electron reliability
  • Plasma damage
  • Power transistors
  • UMOSFETs

ASJC Scopus subject areas

  • Electrical and Electronic Engineering
  • Safety, Risk, Reliability and Quality

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