By Topic

Insights in the Physical Damage of V_{\rm GS} = V_{\rm DS} High-K PMOSFET Degradation in AC Switching Conditions

Sign In

Cookies must be enabled to login.After enabling cookies , please use refresh or reload or ctrl+f5 on the browser for the login options.

Formats Non-Member Member
$31 $13
Learn how you can qualify for the best price for this item!
Become an IEEE Member or Subscribe to
IEEE Xplore for exclusive pricing!
close button

puzzle piece

IEEE membership options for an individual and IEEE Xplore subscriptions for an organization offer the most affordable access to essential journal articles, conference papers, standards, eBooks, and eLearning courses.

Learn more about:

IEEE membership

IEEE Xplore subscriptions

4 Author(s)
La Rosa, G. ; Semicond. R&D Center, IBM Microelectron., Hopewell Junction, NY, USA ; Rauch, S. ; Guarin, F. ; Boffoli, S.

In this paper, the device degradation enhanced by localized drain self-heating (LDSH) effects at VGS = VDS bias condition has been measured and characterized in the pMOSFET transistors of an advanced CMOS HKMG 28-nm bulk technology in both dc (constant voltage) and ac (rectangular pulse) conditions. A comparison with the pMOSFET aging during symmetric (VDS = 0 V) negative bias temperature instability (NBTI) condition gives experimental evidence that the physical damage generated at VGS = VDS bias conditions is dominated by the quasi-permanent component of a symmetric “NBTI-like” thermally activated process with an effective temperature determined by LDSH effects dominating during switching. Similar to conductive (VGS ≈ 1/2VDS) hot carrier phenomena, a quasi-static approximation can be assumed for the VGS = VDS condition during ac switching. In this case, however, the device damage relates to the NBTI response to the effective temperature profile reached during the VGSVDS transients as well as the relation of the associated duty cycles to the values of the LDSH thermal time constants at the stress conditions. The obtained results clearly show that end-of-life projections using dc models will greatly overpredict the level of VGS = VDS degradation expected in typical digital applications. On the contrary, our study provides experimental evidence that the VGS = VDS bias condition is not expected to contribute to device aging during typical digital switching frequencies (f ≈ GHz) and brings further light on the physical mechanism responsible for its observed reduced sensitivity from dc to ac.

Published in:

Device and Materials Reliability, IEEE Transactions on  (Volume:13 ,  Issue: 1 )