Abstract A simple, solution‐processed route to the development of MoO x thin‐films using oxomolybdate precursors is presented. The chemical, structural, and electronic properties these species are characterized in detail, within solution thin‐films, electrospray ionization mass spectrometry, grazing angle Fourier transform infrared spectroscopy, thermogravimetric analysis, atomic force microscopy, X‐ray photoelectron ultraviolet spectroscopy. These analyses show that under suitable...

β-(AlxGa1−x)2O3/β-Ga2O3 heterostructures were grown via plasma-assisted molecular beam epitaxy. The β-(AlxGa1−x)2O3 barrier was partially doped by Ge to achieve a two-dimensional electron gas (2DEG) in Ga2O3. formation of the 2DEG confirmed capacitance–voltage measurements. impact Ga-polishing on both surface morphology and reduction unintentionally incorporated Si at growth interface investigated using atomic force microscopy secondary-ion mass spectrometry. Modulation field-effect...

Mg redistribution into a subsequently regrown GaN epilayer by metalorganic chemical vapor deposition (MOCVD) is studied. Dopant profiles from secondary ion mass spectrometry (SIMS) on n–p–n samples have been analyzed. The regrowth study in Mg-free reactor reveals that Mg-rich film present MOCVD as-grown GaN:Mg base layers and can be removed an acid etch, slow decay the sequentially results this surface film. We believe commonly seen memory effect causes accumulation of surface. From grown...

The effect of substrate roughness on the orientation lamellar microdomains symmetric poly(styrene)-block-poly(methyl methacrylate) [PS-b-PMMA] was investigated. Thin films three molecular weights PS-b-PMMA were prepared organic polyimide and inorganic indium tin oxide substrates whose surfaces characterized for surface energy. It shown, through cross-section transmission electron microscopy (TEM) dynamic secondary ion mass spectroscopy (dSIMS), that above a critical all produced...

Ge and Sn as n-type dopants in (001) β-Ga2O3 films were investigated using plasma-assisted molecular beam epitaxy. The concentration showed a strong dependence on the growth temperature, whereas remains independent of temperature. maximum temperature at which wide range concentrations (from 1017 to 1020 cm−3) could be achieved was 675 °C while same 750 °C. Atomic force microscopy results revealed that higher shows better surface morphology. Therefore, our study reveals tradeoff between...

We report on metalorganic chemical vapor deposition (MOCVD) growth of controllably Si-doped 4.5 μm thick β-Ga2O3 films with electron concentrations in the 1015 cm−3 range and record-high room temperature Hall mobilities up to 200 cm2/Vs, reaching predicted theoretical maximum phonon scattering-limited mobility value for β-Ga2O3. Growth homoepitaxial was performed Fe-doped (010) substrates at a rate 1.9 μm/h using TEGa as Gallium precursor. To probe background concentration, an...

An alternative approach is presented for the plasma-assisted molecular beam epitaxy of high-quality GaN. Under N-rich growth conditions, an unexpected layer-by-layer mode was found a wide range temperatures in GaN thermal decomposition regime (>750°C). Consequently, superior surface morphologies with roughness less than 1nm (rms) have been achieved. For lightly Si-doped films, room-temperature electron mobilities exceeding 1100cm2∕Vs were measured, surpassing commonly insulating...

Transition metals, such as Fe, are commonly used in either layers or substrates to serve deep intentional acceptors realize semi-insulating substrates, regrowth interfaces, buffer layers. The unintentional incorporation of the compensating acceptor subsequent is a major concern epitaxial growth. In this paper, we report on Fe for homoepitaxial growth (010) β-Ga2O3 by plasma-assisted molecular beam epitaxy Fe-doped substrates. was found incorporate heavily into films grown at 500 °C, while...

The synthesis, characterization, and incorporation of phenyl-C61-butyric acid methyl ester (PC61BM)-like derivatives as electron transporting materials (ETMs) in inverted perovskite solar cells (PSCs) are reported. These compounds have the same structure except for substituent, which was varied from to phenyl thienyl pyridyl. three latter performed better than PC61BM PSCs, mainly attributed specific interactions fullerenes with layer, evidenced by X-ray photoelectron spectroscopy (XPS)...

Plasma-assisted molecular beam epitaxial growth of Mg-doped, p-type and Si-doped, n-type m-plane GaN on 6H SiC is demonstrated. Phase-pure, films exhibiting a large anisotropy in film mosaic (∼0.2° full width at half maximum, x-ray rocking curve scan taken parallel to [112¯0] versus ∼2° [0001]) were grown substrates. Maximum hole concentrations ∼7×1018cm−3 achieved with conductivities as high ∼5Ω−1cm−1 without the presence Mg-rich inclusions or inversion domains viewed by cross-section...

Using secondary ion mass spectroscopy we have shown that oxygen incorporation in AlGaN films is dependent upon the III/V growth conditions and temperature of films. grown under excess group III (Ga-rich) exhibited step flow at least a factor 3 less than V (N-rich conditions). We found into decreases as increased. The lowest levels were achieved by growing 750 °C Ga-rich conditions. Possible sources unwanted are discussed.

The lamellar dimension, D, for pure and blended block copolymer (BCPs) thin films of symmetric poly(styrene)-block-poly(methyl methacrylate) was measured using atomic force microscopy analysis surface patterns perpendicularly oriented structures. It approximately verified, SAXS AFM analysis, that perpendicular structures in bounded by a neutral roughened interface did not significantly alter the bulk phase separation thermodynamics. In case blends, it also verified there uniform distribution...

Low temperature (LT) flow modulation epitaxy (FME) or “pulsed” growth was successfully used to prevent magnesium from Metalorganic Chemical Vapor Deposition (MOCVD) grown p-GaN:Mg layers riding into subsequently deposited n-type layers. Mg concentration in the subsequent lowered ∼1 × 1018 cm−3 for a medium at 950 °C 1016 low 700 via FME. The slope of drop FME sample 20 nm/dec—the lowest ever demonstrated by MOCVD. For on implanted GaN layers, regrowth ∼10 nm/dec compared >120 high...

In this work, we report the growth of Mg-doped (010) β-Ga2O3 via plasma-assisted molecular beam epitaxy. Mg concentrations from 2 × 1016 to 8 1020 cm−3 with sharp doping profiles were realized. The incorporation in showed little dependence on temperature and Ga:O flux ratio. Annealing at temperatures 925 1050 °C resulted significant diffusion, thus limiting application lower techniques processing. accumulation near sample surface after diffusion gives insight into rich point–defect...

Abstract In this paper, we report on the growth and electrical characterization of (Al,Si)O dielectrics grown by metalorganic chemical vapor deposition (MOCVD) using trimethylaluminum, oxygen, silane as precursors. The rates, refractive indices, composition films Si(001) were determined from ellipsometry XPS measurements. Crystallinity properties in situ c -plane GaN characterized grazing incidence X-ray diffraction capacitance–voltage with current–voltage measurements, respectively. Si...

An examination of the mechanism electrical doping films poly(3-hexylthiophene) by a strong Brønsted acids reveals heavily doped surface layer that limits diffusion acid into bulk.

We demonstrate InGaN-based semipolar 560 nm micro-light-emitting diodes with 2.5% EQE on high-quality and low-defect-density (20-21) GaN templates grown scalable low-cost sapphire substrates. Through transmission electron microscopy observations, we discuss how the management of misfit dislocations their confinement in areas away from active light-emitting region is necessary for improving device performance. also patterning influences material properties terms surface roughness undesired...

We report on the electrical and structural characterization of Mg-doped Al-rich p-type Al0.69Ga0.31N alloys SiC substrate grown by metal organic chemical vapor deposition. The impact growth conditions dopant activation annealing conductivity was investigated. most efficient achieved in N2 gas at 1000°C for 3min presence a SiO2 cap. p-GaN contact layer thickness also studied. Higher temperature resulted lower Mg incorporation, constant concentration resistivity increased with increase...

Deep ultraviolet light emitting diode structures with a peak wavelength of 275 nm were grown by metalorganic chemical vapor deposition on (0001) silicon carbide. Despite its strong absorption, carbide was chosen as substrate rather than sapphire for improved thermal conductivity and the potential vertically conducting devices. An output power 0.11 mW observed at 300 mA DC during single device on-wafer testing, powers 2.09 1.3 A obtained from packaged, silicone encapsulated array five Forward...

Migration of additives to organic/metal interfaces can be used self-generate interlayers in organic electronic devices. To generalize this approach for various additives, metals, and devices it is first necessary study the dynamics additive migration from bulk top interface. In study, we focus on a known cathode interlayer material, polyethylene glycol (PEG), as P3HT:PC71BM blends its blend/Al interface during metal deposition effect solar cell (OSC) performance. Using dynamic secondary ion...

Free-standing and supported films with a lateral gradient in composition were prepared using blends of poly(acrylic acid) (PAA)/sodium salt its copolymers acrylamide (AAm) an applied electric field. The gradients stabilized by complexation carboxylate groups metal species. To find the favorable conditions components for successful blending interaction Fe Ce species, we studied two PAA samples molecular weights 2000 15 000 Da AA AAm (with 10 70 wt % units) these Fe(III) Ce(IV) ions. structure...