Mobility Variation Due to Interface Trap Generation in Plasma Oxynitrided PMOS Devices

By Ahmad Ehteshamul Islam1, Souvik Mahapatra2, Muhammad A. Alam3

1. Air Force Research Laboratory 2. Indian Institute of Technology Bombay 3. Purdue University

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Mobility degradation due to generation of interface
traps, Δµeff(NIT), is a well-known phenomenon that has been
theoretically interpreted by several mobility models. Based on
these analysis, there is a general perception that Δµeff(NIT) is
relatively insignificant (compared to Δµeff due to ionized
impurity) and as such can be safely ignored for performance and
reliability analysis. Here, we investigate the importance of
considering Δµeff(NIT) for reliability analysis by analyzing a wide
variety of plasma oxynitride PMOS devices using both
parametric and physical mobility models. We find that contrary
to popular belief this correction is fundamentally important for
robust and uncorrupted estimates of the key reliability
parameters like threshold-voltage shift, lifetime projection,
voltage acceleration factor, etc. Therefore, in this paper, we
develop a generalized algorithm for estimating Δµeff(NIT) for
plasma oxynitride PMOS devices and systematically explore its
implications for NBTI-specific reliability analysis.


Vrajesh D. Maheta
Hitesh Das
Souvik Mahapatra

Sponsored by

We acknowledge financial supports from Applied Materials,
Renesas Technologies and Taiwan Semiconductor Manufacturing
Company in this work. Thanks to Network for Computational
Nanotechnology at Purdue University for providing the necessary
computational facilities.


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and Circuit: Models, Mechanisms and Scaling Effects," IEDM
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[3] S. Mahapatra, K. Ahmed, D. Varghese, A. E. Islam, G. Gupta,
L. Madhav, D. Saha, and M. A. Alam, "On the Physical
Mechanism of NBTI in Silicon Oxynitride p-MOSFETs: Can
Differences in Insulator Processing Conditions Resolve the
Interface Trap Generation versus Hole Trapping Controversy?,"
Proc IEEE IRPS, pp. 1-9, 2007.


“Mobility Degradation Due to Interface Traps in Plasma Oxinitride PMOS Devices”, A. E. Islam, V. D. Maheta, H. Das, S. Mahapatra, and M. A. Alam, Proc. of International Reliability Physics Symposium, Apr 2008, pp. 87-96.

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Researchers should cite this work as follows:

  • Ahmad Ehteshamul Islam, Souvik Mahapatra, Muhammad A. Alam (2008), "Mobility Variation Due to Interface Trap Generation in Plasma Oxynitrided PMOS Devices,"

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