Unification of contemporary negative bias temperature instability models for p-MOSFET energy degradation Nissar Mohammad Karim n , Sadia Manzoor, Norhayati Soin Department of Electrical Engineering, University of Malaya, Kuala Lumpur 50603, Malaysia article info Article history: Received 10 May 2012 Received in revised form 14 June 2013 Accepted 16 June 2013 Available online 16 July 2013 Keywords: Energy degradation Reliability CMOS lifetime abstract In this article, we present contemporary research advancements on negative bias temperature instability (NBTI) degradation models which are responsible for p-MOSFET energy degradation. Hence, we propose a unified theory on the recent models in order to predict the transistor aging by considering the energy effect. Development of the newly modified model in this article is followed by a reassesment on NBTI models considering energy degradation. Unlike many of the previous models, the proposed theory of NBTI degradation projects the reliability in both stress and recovery phase; which follows power law. & 2013 Elsevier Ltd. All rights reserved. Contents 1. Introduction ........................................................................................................ 776 2. Reassessment of NBTI models .......................................................................................... 777 2.1. Reaction–diffusion (RD) model ................................................................................... 777 2.2. Maricau and Gielen ............................................................................................ 777 2.3. Contemporary degradation models................................................................................ 778 3. Discussion ......................................................................................................... 779 4. Conclusion ......................................................................................................... 779 Acknowledgement....................................................................................................... 779 References ............................................................................................................. 779 1. Introduction In the field of engineering, reliability has always been an issue to affect system performance and energy consumption. In this regard, previously there has been works on mini and mega power systems [1,2]. Many of these works focused on reliability based modeling for improvising energy efficiency [3–5]. On the other hand, most of the power electronic devices we have around are mainly composed of integrated circuits (IC). And, CMOS is widely used in the IC implementation technology. We found that there are still scopes to work on the reliability aspect of energy efficiency of sub-nanometer CMOS structures. Energy shift of any CMOS system can be affected due to various reasons like hot carrier injection [HCI], time dependent dielectric breakdown [TDDB] and negative bias temperature instability [NBTI]. But among these, at high temperature and at nanoscale technology NBTI is the most dominant type of defect affecting reliability as per Mishra et al. [6]. In comparison with HCI and TDDB, for lower technology nodes, NBTI is the most catastrophic reliability issue to cause shift in threshold voltage, drain current, linear drain current, saturation current, channel mobility, subthreshold slope, off current and transconductance [7,8]. The degradation of threshold voltage and drain current cause energy degradation. Therefore taking [7,8] into account, energy degradation will be more due NBTI. Moreover, as geometric and process advancement continues further, NBTI becomes more catastrophic at a high temperature [9]. NBTI degrades transistor performance which mainly include threshold voltage, linear drain current, saturation current, trans- conductance, channel mobility, sub threshold slope and off cur- rent. The degradation of any of these parameters can result in Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/rser Renewable and Sustainable Energy Reviews 1364-0321/$ - see front matter & 2013 Elsevier Ltd. All rights reserved. http://dx.doi.org/10.1016/j.rser.2013.06.004 n Corresponding author. Tel.: +60169695243; fax: +60 3 79675316. E-mail address: kingnissarkarim@gmail.com (N.M. Karim). Renewable and Sustainable Energy Reviews 26 (2013) 776–780