We are able to achieve two different GaN semipolar surfaces by growing on patterned sapphire substrates: (101̄1) GaN on (112̄3) sapphire and (112̄2) on (101̄2). By this approach, the growth of a coalesced semipolar layer on a large area of about two inches diameter is possible. Well known from the c-plane direction, an in-situ deposited SiN interlayer could reduce the defect density also in semipol...

Approximately 4-μm-thick GaN epitaxial films were directly grown onto a GaN/sapphire template, sapphire, Si(111), and Si(100) substrates by high-temperature pulsed laser deposition (PLD). The influence of the substrate type on the crystalline quality, surface morphology, microstructure, and stress states was investigated by X-ray diffraction (XRD), photoluminescence (PL), atomic force microscop...

BACKGROUND Acute kidney injury (AKI) remains a deadly condition. Tissue inhibitor of metalloproteinases (TIMP)-2 and insulin-like growth factor binding protein (IGFBP)7 are two recently discovered urinary biomarkers for AKI. We now report on the development, and diagnostic accuracy of two clinical cutoffs for a test using these markers. METHODS We derived cutoffs based on sensitivity and spec...

Sapphire nanopatterning is the key solution to GaN light emitting diode (LED) light extraction. One challenge is to etch deep nanostructures with a vertical sidewall in sapphire. Here, we report a study of the effects of two masking materials (SiO2 and Cr) and different etching recipes (the reaction gas ratio, the reaction pressure and the inductive power) in a chlorine-based (BCl3 and Cl2) ind...

In the present work, biobased protic ionic liquid crystal bis(2-hydroxyethyl) ammonium palmitate (DPA) has been studied as neat lubricant under linear reciprocating sliding at 75 °C, in crystalline region, and 110 above its melting point. Three different tribopairs have using AISI 52100 steel, 316L stainless steel sapphire balls against disks. Tribological results °C are agreement with pairs co...

• In 1982 researchers at Lincoln Laboratory operated a tunable laser based on Ti:Al20 3 for the first time. A wide variety ofdevelopments in Ti:Alz0 3 1aser technology then followed the advances in crystal growth that occurred during the mid-1980s. Since that time researchers have demonstrated high efficiency, wide tunability, frequency-stable continuous-wave operation, and generation of very s...

Today pressure transmitters have high requirements such as reliability, quality, measurementaccuracy, the ability to work in extreme conditions and resistance aggressive environments.The main problems achieving these target indicators are: cost of originalproducts, laboriousness technological process serial production, limitationsthat affect accuracy original devices. Solving is thesubject this...

This Licentiate thesis summarizes the work carried out by the author the years 2004 to 2008 at the University of Iceland and the Royal Institute of Technology (KTH) in Sweden. The aim of the project was to investigate the structure of sapphire (?-Al2O3) surfaces, both for pure scientific reasons and also for potential use as substrate for GaN-growth by molecular beam epitaxy. More generally the...