Experimental-Modeling Framework for Identifying Defects Responsible for Reliability Issues in 2D FETs.

In this work, a self-consistent method is used to identify and describe defects plaguing 300 mm integrated 2D field-effect transistors. This method requires measurements of the transfer characteristic hysteresis combined with physics-based modeling of charge carrier capture and emission processes using technology computer aided design (TCAD) tools. The interconnection of experiments and simulations allows one to thoroughly characterize charge trapping/detrapping by/from defects, depending on their energy position.

Efficient Direct Band-Gap Transition in Germanium by Three-Dimensional Strain.

Complementary to the development of highly three-dimensional (3D) integrated circuits in the continuation of Moore's law, there has been a growing interest in new 3D deformation strategies to improve the device performance. To continue this search for new 3D deformation techniques, it is essential to explore beforehand, using computational predictive methods, which strain tensor leads to the desired properties. In this work, we study germanium (Ge) under an isotropic 3D strain on the basis of first-principles methods.

Variations of paramagnetic defects and dopants in geo-MoS from diverse localities probed by ESR.

Exfoliated flakes from molybdenite crystals often still serve as benchmark substrates for two-dimensional MoS fundamental and device-oriented research. In this article, results are reported of a multi-frequency electron paramagnetic resonance (EPR) study on a series of natural 2H MoS crystals taken from various (seven) geological sites with the intent to explore the variations in quality and properties in terms of occurring paramagnetic point defects, with particular focus on the assessment of the predominant type of impurity dopant. The sample set covers three types of overall doping regimes, i.

Band alignment at interfaces of two-dimensional materials: internal photoemission analysis.

The article overviews experimental results obtained by applying internal photoemission (IPE) spectroscopy methods to characterize electron states in single- or few-monolayer thick two-dimensional materials and at their interfaces. Several conducting (graphene) and semiconducting (transitional metal dichalcogenides MoS, WS, MoSe, and WSe) films on top of thermal SiOhave been analyzed by IPE, which reveals significant sensitivity of interface band offsets and barriers to the details of the material and interface fabrication, indicating violation of the Schottky-Mott rule. This variability is associated with charges and dipoles formed at the interfaces with van der Waals bonding as opposed to the chemically bonded interfaces of three-dimensional semiconductors and metals.

Material-Selective Doping of 2D TMDC through AlO Encapsulation.

For the integration of two-dimensional (2D) transition metal dichalcogenides (TMDC) with high-performance electronic systems, one of the greatest challenges is the realization of doping and comprehension of its mechanisms. Low-temperature atomic layer deposition of aluminum oxide is found to n-dope MoS and ReS but not WS. Based on electrical, optical, and chemical analyses, we propose and validate a hypothesis to explain the doping mechanism.