Heteroatom Functionalization of H-Terminated Diamond Surfaces.

Diamond surface functionalization has received significant research interest recently. Specifically, H-termination has been widely adopted because it endows the diamond surface with negative electron affinity and the hole carrier is injected in the presence of surface transfer dopants. Exploring different functional groups' attachment on diamond surfaces and their impact on the electronic structure, using wet and dry chemical approaches, would hence be of interest in engineering diamond as a semiconductor.

Phase Stability of Hexagonal/Cubic Boron Nitride Nanocomposites.

Boron nitride (BN) is an exceptional material, and among its polymorphs, two-dimensional (2D) hexagonal and three-dimensional (3D) cubic BN (h-BN and c-BN) phases are most common. The phase stability regimes of these BN phases are still under debate, and phase transformations of h-BN/c-BN remain a topic of interest. Here, we investigate the phase stability of 2D/3D h-BN/c-BN nanocomposites and show that the coexistence of two phases can lead to strong nonlinear optical properties and low thermal conductivity at room temperature.

Chip-Scale Droop-Free Fin Light-Emitting Diodes Using Facet-Selective Contacts.

Sub-micron-size light sources are currently extremely dim, achieving nanowatt output powers due to the current density and temperature droop. Recently, we reported a droop-free fin light-emitting diode (LED) pixel that at high current densities becomes a laser with record output power in the microwatt range. Here, we show a scalable method for selectively metallizing fins via their nonpolar side facet that allows electrical injection to sub-200 nm wide -ZnO fins on -GaN with at least 0.

Utilizing Fused Filament Fabrication for Printing Iron Cores for Electrical Devices.

This work details a polyolefin-elastomer-based binder system to prepare fused filament fabrication (FFF) filaments and print cores for coils for electrical engines. The processability, homogeneity, and thermal properties of the polyolefin-elastomer-based filaments are explored. A two-step debinding and sintering process was established for manufacturing dense iron parts.

Indium Tin Oxide Film Characteristics for Cathodic Stripping Voltammetry.

The combination of conductivity, optical transparency, and wide anodic potential window has driven significant interest in indium tin oxide (ITO) as an electrode material for electrochemical measurements. More recently, ITO has been applied to the detection of trace metals using cathodic stripping voltammetry (CSV), specifically manganese (Mn). However, the optimization of ITO fabrication for a voltammetric method such as CSV is yet to be reported, nor have the microstructural properties of ITO been investigated for CSV.

Rapid Wafer-Scale Growth of Polycrystalline 2H-MoS by Pulsed Metalorganic Chemical Vapor Deposition.

High volume manufacturing of devices based on transition metal dichalcogenide (TMD) ultra-thin films will require deposition techniques that are capable of reproducible wafer-scale growth with monolayer control. To date, TMD growth efforts have largely relied upon sublimation and transport of solid precursors with minimal control over vapor phase flux and gas-phase chemistry, which are critical for scaling up laboratory processes to manufacturing settings. To address these issues, we report a new pulsed metalorganic chemical vapor deposition (MOCVD) route for MoS film growth in a research-grade single-wafer reactor.

Surface-directed Nanoepitaxy on a Surface with an Irregular Lattice.

Understanding and developing metrics on how nanocrystals respond to local external surface stimuli at their interfaces during growth or operation is a key step in advancing scalable and deterministic approaches for fabricating functional one- and two-dimensional (1D and 2D) nanoscale networks. Here, we present early results on a general approach for surface-directed nanocrystal epitaxy on a surface with an irregular lattice constant. We show that patches of lattice matched areas as small as 7 nm in a background of surface lattice disorder could satisfy the condition for epitaxial growth of a crawling nanocrystal over the disordered region.