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In this study, an area‐selective metal‐organic vapor‐phase epitaxy (MOVPE) for trench‐confined InP‐based epitaxial regrowth in‐between arrayed rectangular‐shaped device elements is reported. Test structures are fabricated to investigate the influence of MOVPE growth and other processing parameters on regrowth control, doping incorporation, and morphology. For correctly chosen crystallographic mesa orientation and mask geometry, good control of growth selectivity, layer morphology, and doping concentration can be achieved, although with an enhanced and non‐constant growth rate. This is discussed in terms of orientation‐dependent growth rate and loading effects. In addition, a selective etch and regrowth approach which allows for the processing of field‐effect transistors of significance for spatial light modulators with trench‐integrated driver electronics is successfully implemented. [ABSTRACT FROM AUTHOR]

Highlights: [•] A diode was designed in the shape of a silicon cube with p–n junctions on all sides. [•] The purpose was to create an X-ray detector with angular independent response. [•] The cubes were manufactured with a micromachining process. [•] The angular variation in the response was reduced with a factor 7. [ABSTRACT FROM AUTHOR]

Looks at how distributed feedback (DFB) laser parameters have been determined using a method based on least-square fitting of theoretical spectra to measured, subthreshold DFB laser emission spectra. Identification of such parameters; Brief information on the method used.

Generation of large areas of graphene possessing high quality and uniformity will be a critical factor if graphene-based devices/sensors are to be commercialized. In this work, epitaxial graphene on a 2" SiC wafer was used to fabricate sensors for the detection of illicit drugs (amphetamine or cocaine). The main target application is on-site forensic detection where there is a high demand for reliable and cost-efficient tools. The sensors were designed and processed with specially configured metal electrodes on the graphene surface by utilizing a series of anchors where the metal contacts are directly connected on the SiC substrate. This has been shown to improve adhesion of the electrodes and decrease the contact resistance. A microfluidic system was constructed to pump solutions over the defined graphene surface that could then act as a sensor area and react with the target drugs. Several prototypic systems were tested where non-covalent interactions were used to localize the sensing components (antibodies) within the measurement cell. The serendipitous discovery of a wavelength-dependent photoactivity for amphetamine and a range of its chemical analogs, however, limited the general application of these prototypic systems. The experimental results reveal that the drug molecules interact with the graphene in a molecule dependent manner based upon a balance of π -stacking interaction of the phenyl ring with graphene (p-doping) and the donation of the amine nitrogens lone pair electrons into the π - π *-system of graphene (n-doping). [ABSTRACT FROM AUTHOR]