Ohmic contacts to AlGaN/GaN heterostructures, which have low contact resistance and a good surface morphology, are required for the development of high temperature, high power and high frequency electronic devices. The paper presents the investigation of a Ti/Al based Ti/Al/Ni/Au ohmic contact to AlGaN/GaN heterostructures. Multilayer metallization of Ti/Al/Ni/Au was evaporated by an electron g...

We demonstrate experimentally the manipulation of supercurrent in Al-AlOx-Ti Josephson tunnel junctions by injecting quasiparticles in a Ti island from two additional tunnel-coupled Al superconducting reservoirs. Both supercurrent enhancement and quenching with respect to equilibrium are achieved. We demonstrate cooling of the Ti line by quasiparticle injection from the normal state deep into t...

Metallic-intermetallic laminate (MIL) composites are promising materials for structural applications especially in the aerospace industry. One of the interesting laminate composites is the Ti-TiAl 3 multilayer. In this work, commercially pure sheets of aluminum and titanium with almost equal thickness of around 0.5 mm were explosively joined. The achieved multilayers were annealed at 630 ℃in di...

This licentiate thesis reports experimental and theoretical work on the high temperature mechanical properties and the thermal stability of cubic (c)-(Ti-Cr-Al)1-N1 coatings. It is demonstrated that it is possible to tailor and improve the properties of hard nitride coatings by different degrees of multicomponent alloying. When Cr is added to Ti-Al-N the coatings exhibit age hardening up to 100...

With using the carbon nano-tube (CNT) of high chemical activity, nano-TiCx particles with different growth shapes were synthesized through the self-propagating high temperature in the 80 wt.% metal (Cu, Al, and Fe)-Ti-CNT systems. The growth shapes of the TiCx particles are mainly octahedron in the Cu- and Al-Ti-CNT systems, while mainly cube- and sphere-like in the Fe-Ti-CNT system.

Ni-20 wt pct Cr wires, as individual wires or within 3D woven structures, are alloyed with Mo, Al, and Ti by gas-phase surface deposition and volume interdiffusion. Mo deposition creates Mo-rich coating and Kirkendall pores. Al+Ti co-deposition creates uniform triple-layered coating. The resulting homogenized and aged Ni-(17.4-19.6)Cr-(1.6-1.8)Al-(2.5-3.6)Ti-(1.54.5)Mo(wt pct) wires exhibit c+ ...

The use of water-soluble sacrificial layer Sr$_3$Al$_2$O$_6$ has tremendously boosted the research on freestanding functional oxide thin films, especially thanks to its ultimate capability produce high-quality epitaxial perovskite films. However, costly single-crystalline substrates, e.g. SrTiO$_3$, were generally discarded after obtaining Here, we demonstrate that SrTiO$_3$ substrates can be r...

This article investigates high dielectric constant gate insulators for GaN-based devices. Exploiting TiO2 as a high-j insulator typically compromises leakage current and temperature stability of the film. In this work, the authors compare TiO2 mixed with either Al2O3 or HfO2 to form composite films Ti-Al-O and Ti-Hf-O, respectively, deposited by atomic layer deposition on both AlGaN/GaN and InA...