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Given that pediatric genomic sequencing (GS) may have implications for the health and well-being of both the child and family, a clearer understanding of the key drivers of the utility of GS from the family perspective is needed. The purpose of this study is to explore what is important to caregivers of pediatric patients regarding clinical GS, with a focus on family-level considerations. We conducted semi-structured interviews with caregivers (n=41) of pediatric patients who had been recommended for or completed GS that explored the scope of factors caregivers considered when deciding whether to pursue GS for their child. We analyzed the qualitative data in multiple rounds of coding using thematic analysis. Caregivers raised important family-level considerations, in addition to those specifically for their child, which included wanting the best chance at good quality of life for the family, the ability to learn about family health, the impact on the caregiver’s well-being, privacy concerns among family members, and the cost of testing to the family. We developed a framework of key drivers of utility consisting of four domains that influenced caregivers’ decision making: underlying values, perceived benefits, perceived risks, and other pragmatic considerations regarding GS. These findings can inform measurement approaches that better capture the utility of pediatric GS for families.

Titanium nitride (TiN) is a recent material of interest for plasmonics and electrodes due to its high-temperature stability, robustness, and CMOS-compatibility. Previously we found that optical plasmonic quality correlated with the microstructural quality of TiN, and both properties depended on deposition temperature: TiN grown at 550 °C resulted in favorable optical properties for plasmonic materials. The present work investigates strain and stoichiometry of TiN films as a result of varying deposition temperature. Six (111)-oriented TiN films were grown on c-sapphire with reactive magnetron sputtering; substrate temperatures ranged from 280 °C to 760 °C. The TiN films were analyzed with x-ray photoelectron spectroscopy, x-ray diffraction, and high-resolution transmission electron microscopy to examine composition, strain, lattice constants, unit cell angles, dislocation defects, mosaicity, and low-angle tilt boundaries. We found that lattice constants only remained a constant 4.242 A at temperatures above 490 °C. Above this substrate temperature the deviation from a 90˚ unit cell angle remained at a minimum, indicating less strain. When combined with the previously-found plasmonic material properties of the films, this trend suggests that more relaxed films grow above 490 °C and yield lower relative optical loss, and favorable plasmonic material quality factors. Rocking curves suggested fewest dislocation defects and least mosaicity in the optically favorable 550 °C film. The results of this work indicate that microstructure, most significantly strain and defects, correlates with optical properties in TiN. This work emphasizes the importance of specific deposition conditions—in this case, substrate temperature—to minimize strain and defect density for achieving optimal plasmonic properties for TiN thin films.

Scandium nitride (ScN) is a degenerate n-type semiconductor with very high carrier concentrations, low resistivity, and carrier mobilities comparable to those of transparent conducting oxides such as zinc oxide. Because of its small lattice mismatch to gallium nitride (GaN)

Titanium nitride (TiN) is a mechanically robust, high-temperature stable, metallic material receiving considerable attention for resilient plasmonics. In this work, the authors fabricated six heteroepitaxial TiN films on sapphire using controllably unbalanced reactive magnetron sputtering. They examined the effect of substrate growth temperature on the plasmonic and crystalline quality of the film. Optical properties of all films were obtained from spectroscopic ellipsometry; plasmonic quality factors were determined from the real and imaginary parts of the dielectric function. The authors determined crystallinity using x-ray diffraction and surface morphology using atomic force microscopy. X-ray diffraction showed (111) TiN peaks with Pendellosung fringes indicating consistent heteroepitaxy. Atomic force microscopy showed smooth surfaces with root mean square surface roughness ranging from 0.2 to 2.6 nm. Based on this characterization, the authors determined that the substrate deposition temperature of 550 °C yielded (111)-oriented heteroepitaxial TiN with minimal surface roughness. The authors found that 550 °C also gave highest plasmonic quality factors for all wavelengths, approaching the values of today's best plasmonic materials (such as Au and Ag). Further, the Q-factors at wavelength 1550 nm inversely correlated with calculated lattice constants. Their results indicate that the plasmonic response of TiN is directly linked with structural quality of the film.Titanium nitride (TiN) is a mechanically robust, high-temperature stable, metallic material receiving considerable attention for resilient plasmonics. In this work, the authors fabricated six heteroepitaxial TiN films on sapphire using controllably unbalanced reactive magnetron sputtering. They examined the effect of substrate growth temperature on the plasmonic and crystalline quality of the film. Optical properties of all films were obtained from spectroscopic ellipsometry; plasmonic quality factors were determined from the real and imaginary parts of the dielectric function. The authors determined crystallinity using x-ray diffraction and surface morphology using atomic force microscopy. X-ray diffraction showed (111) TiN peaks with Pendellosung fringes indicating consistent heteroepitaxy. Atomic force microscopy showed smooth surfaces with root mean square surface roughness ranging from 0.2 to 2.6 nm. Based on this characterization, the authors determined that the substrate deposition temperature of 5...

InAs growth on GaAs has been studied extensively and most recently for the self-assembly of quantum dots on the surface. In this work, we have studied the growth conditions to form planar InAs, at an In beam-equivalent pressure of 3.1×10−8 Torr, under the metal rich (4×2) reconstruction and the subsequent formation of quantum dots (QDs) condensed from this layer by a rapid change in the As4 pressure. Atomic force microscopy (AFM) studied the surface morphology of InAs resulting from a nominal 12 ML growth with various As4 growth pressures while maintaining a metal rich condition. It was found that the surface roughness was dependent on the As4 pressure. At the higher As4 pressures studied, the growth was extremely rough and much smoother at the lower As4 pressures. For a beam-equivalent pressure of 1×10−7 Torr for As4 and 3.1×10−8 Torr for In, growth was seen to remain planar for a deposition thickness up to 3 ML. AFM analysis showed that a fingered morphology was formed with a roughness of ∼1 ML. When th...