The degradation of MOSFETs induced by the via etching of interlayer low-k polymers


Trabzon L., Awadelkarim O.

13th International Conference on Microelectronics (ICM 2001), Rabat, Malta, 29 - 31 October 2001, pp.103-106 identifier

  • Publication Type: Conference Paper / Full Text
  • City: Rabat
  • Country: Malta
  • Page Numbers: pp.103-106

Abstract

We report on the effects of via etching through two low-k polymers (FLARE and BCB) used as Interlayer dielectrics, on the prerformance of 0.35 _ m long n-channel MOSFETs with 45-Angstrom-thick gate oxides. It is observed that the via etching of the polymers damages the MOSFET and that this damage Is severer in the case of BCB via etching. The inclusion of and insulating Si3N4 layer underneath the polymer is found to be very effective in reducing the MOSFET's damage. Alternatively, annealing In forming gas at 350 degreesC for 30 min after the via etching can further eliminate device damage.