Compact Physics Hot-Carrier Degradation Model Valid over a Wide Bias Range.

We develop a compact physics model for hot-carrier degradation (HCD) that is valid over a wide range of gate and drain voltages (Vgs and Vds, respectively). Special attention is paid to the contribution of secondary carriers (generated by impact ionization) to HCD, which was shown to be significant under stress conditions with low Vgs and relatively high Vds. Implementation of this contribution is based on refined modeling of carrier transport for both primary and secondary carriers. To validate the model, we employ foundry-quality n-channel transistors and a broad range of stress voltages {Vgs,Vds}.

Correlated Time-0 and Hot-Carrier Stress Induced FinFET Parameter Variabilities: Modeling Approach.

We identify correlation between the drain currents in pristine n-channel FinFET transistors and changes in time-0 currents induced by hot-carrier stress. To achieve this goal, we employ our statistical simulation model for hot-carrier degradation (HCD), which considers the effect of random dopants (RDs) on HCD. For this analysis we generate a set of 200 device instantiations where each of them has its own unique configuration of RDs. For all "samples" in this ensemble we calculate time-0 currents (i.e. currents in undamaged FinFETs) and then degradation characteristics such as changes in the linear drain current and device lifetimes. The robust correlation analysis allows us to identify correlation between transistor lifetimes and drain currents in unstressed devices, which implies that FinFETs with initially higher currents degrade faster, i.e. have more prominent linear drain current changes and shorter lifetimes. Another important result is that although at stress conditions the distribution of drain currents becomes wider with stress time, in the operating regime drain current variability diminishes. Finally, we show that if random traps are also taken into account, all the obtained trends remain the same.

The FAST module: an add-on unit for driving commercial scanning probe microscopes at video rate and beyond.

We present the design and the performance of the FAST (Fast Acquisition of SPM Timeseries) module, an add-on instrument that can drive commercial scanning probe microscopes (SPM) at and beyond video rate image frequencies. In the design of this module, we adopted and integrated several technical solutions previously proposed by different groups in order to overcome the problems encountered when driving SPMs at high scanning frequencies. The fast probe motion control and signal acquisition are implemented in a way that is totally transparent to the existing control electronics, allowing the user to switch immediately and seamlessly to the fast scanning mode when imaging in the conventional slow mode. The unit provides a completely non-invasive, fast scanning upgrade to common SPM instruments that are not specifically designed for high speed scanning. To test its performance, we used this module to drive a commercial scanning tunneling microscope (STM) system in a quasi-constant height mode to frame rates of 100 Hz and above, demonstrating extremely stable and high resolution imaging capabilities. The module is extremely versatile and its application is not limited to STM setups but can, in principle, be generalized to any scanning probe instrument.