Future of GaN RF Technology in Europe
In the last years GaN has remained a key technology in Europe in particular, but not only, for RF Applications. After an intensive period of research and development the scope has shifted towards industrialization and product development. This is especially true for the applications up to around 20GHz where systems are now being built using European GaN-based components. At the same time, an increasing part of the research activity has moved toward higher frequencies beyond 20GHz.
Comparison of the performances of an InAlN/GaN HEMT with a Mo/Au gate or a Ni/Pt/Au gate
Abstract In this paper GaN based HEMT structures characterized by a 6.3 nm InAlN barrier layer and a different gate contact (Mo/Au and Ni/Pt/Au) are described. The effects of a different gate contact structure on DC and pulsed main characteristics are discussed. Despite no meaningful variation is noticed during DC analysis, pulsed evaluation demonstrates that the use of a Mo/Au gate contact leads to an improvement of trapping characteristics. Reliability performances of the devices are finally investigated by means of a OFF state three terminals step stress, proving that the use of a Mo/Au stack does not affect significantly the device stability during the stress.
Mucoadhesive Nanoparticles for Drug Delivery to the Anterior Eye
While the use of topical drops for the delivery of drugs to the anterior of the eye is well accepted, it is far from efficient with as little as 5% of the drug instilled on the eye actually reaching the target tissue. The ability to prolong the residence time on the eye is desirable. Based on the acceptability of 2-hydroxyethyl methacrylate based polymers in contact lens applications, the current work focuses on the development of a poly(2-hydroxyethyl methacrylate (HEMA)) nanoparticle system. The particles were modified to allow for degradation and to permit mucoadhesion. Size and morphological analysis of the final polymer products showed that nano-sized, spherical particles were produced. FTIR spectra demonstrated that the nanoparticles comprised poly(HEMA) and that 3-(acrylamido)phenylboronic acid (3AAPBA), as a mucoadhesive, was successfully incorporated. Degradation of nanoparticles containing N,N′-bis(acryloyl)cystamine (BAC) after incubation with DL-dithiothreitol (DTT) was confirmed by a decrease in turbidity and through transmission electron microscopy (TEM). Nanoparticle mucoadhesion was shown through an in-vitro zeta potential analysis.