Traditional von Neumann computing architecture with separated computation and storage units has already impeded the data processing performance and energy efficiency, calling for emerging neuromorphic electronic and optical devices and systems which can mimic the human brain to shift this paradigm. Material-level innovation has become the key component to this revolution of information technology. Chalcogenide phase-change material (PCM) as a well-acknowledged data-storage medium is a promising candidate to tackle this challenge. In this review, the use of PCMs to implement artificial neurons and synapses from both the electronic and optical respects is discussed, and in particular, the structure-property physics and transition dynamics that enable such brain-inspired and in-memory computing applications are emphasized. Recent advances on the atomic-level amorphous and crystalline structures, transition mechanisms, materials optimization and design, neural and synaptic devices, brain-inspired chips, and computing systems, as well as the future opportunities of PCMs, are summarized and discussed.
In this work, we present a comprehensive theoretical and experimental study of quantum confinement in layered platinum diselenide (PtSe 2 ) films as a function of film thickness. Our electrical measurements, in combination with density functional theory calculations, show distinct layer-dependent semimetal-to-semiconductor evolution in PtSe 2 films, and highlight the importance of including van der Waals interactions, Green's function calibration, and screened Coulomb interactions in the determination of the thickness-dependent PtSe 2 energy gap. Large-area PtSe 2 films of varying thickness (2.5-6.5 nm) were formed at 400°C by thermally assisted conversion of ultra-thin platinum films on Si/SiO 2 substrates. The PtSe 2 films exhibit p-type semiconducting behavior with hole mobility values up to 13 cm 2 /V·s. Metal-oxide-semiconductor field-effect transistors have been fabricated using the grown PtSe 2 films and a gate field-controlled switching performance with an I ON /I OFF ratio of >230 has been measured at room temperature for a 2.5-3 nm PtSe 2 film, while the ratio drops to <2 for 5-6.5 nm-thick PtSe 2 films, consistent with a semiconductingto-semimetallic transition with increasing PtSe 2 film thickness. These experimental observations indicate that the low-temperature growth of semimetallic or semiconducting PtSe 2 could be integrated into the back-end-of-line of a silicon complementary metaloxide-semiconductor process.npj 2D Materials and Applications (2019) 3:33 ; https://doi.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.