This article is focused on GaN-based power amplifiers for applications up to 10 GHz. Several PAs developed in both MMIC and hybrid technologies for different RF and microwave frequency bands will be described. In particular, the designs of two ultra-wideband (UWB) PAs are reported together with experimental results. The first one is based on commercial GaN-on-SiC technology while the other one ...

Hall electron mobility H and sheet concentration ns in AlGaN/GaN heterostructures have been measured from 77 to 1020 K. The effect of the deposited Al2O3 layer is also investigated with varying its thickness. It is found that H decreases monotonously with the temperature T and its dependence is well approximated with the function of H=4.5 10 3 exp −0.004T in the temperatures over 350 K. The fun...

Uniform GaN nanorod arrays are grown vertically by selective area growth on (left angle bracket 0001 right angle bracket) substrates. The GaN nanorods present six nonpolar {1⁻100} facets, which serve as growth surfaces for InGaN-based light-emitting diode quantum well active regions. Compared to growth on the polar {0001} plane, the piezoelectric fields in the multiple quantum wells (MQWs) can ...

Gallium Nitride (GaN) is a unique material system that has been heavily exploited for photonic devices thanks to ultraviolet-to-terahertz spectral tunability. However, without a cost effective approach, GaN technology is limited to laboratory demonstrations and niche applications. In this investigation, integration of GaN on Silicon (100) substrates is attempted to enable widespread application...

The authors investigate the effect of the thermal boundary resistance between the GaN layer and the substrate on the current–voltage characteristics of GaN MESFETs. Using material specific models for carrier drift-diffusion and thermal conductivity the authors determine the dependence of the breakdown voltage on thermal boundary resistance. The mechanism of the thermal breakdown in GaN transist...

The strain induced by lattice mismatch at the interface is responsible for the different value of the band discontinuities observed recently for the AlN/GaN (AlN on GaN) and the GaN/AlN (GaN on AlN) polar (0001) interface. We present a first-principles calculation of valence band offsets, interface dipoles, strain-induced piezoelectric fields, relaxed geometric structure, and formation energies...

Many aspects of and factors required for DNA replication are conserved across all three domains of life, but there are some significant differences surrounding lagging-strand synthesis. In Archaea, a 5'-to-3' exonuclease, related to both bacterial RecJ and eukaryotic Cdc45, that associates with the replisome specifically through interactions with GINS was identified and designated GAN (for GINS...

Several dihedral angles prediction methods were developed for protein structure prediction and their other applications. However, distribution of predicted angles would not be similar to that of real angles. To address this we employed generative adversarial networks (GAN) which showed promising results in image generation tasks. Generative adversarial networks are composed of two adversarially...

temperature. This wide spectral range enables potential applications from the infrared to the deep ultraviolet regions of the electromagnetic spectrum. This makes GaN-based nitrides one of the most important materials for light sources such as light-emitting diodes (LEDs). [ 1–5 ] Sapphire has long been used as a substrate for GaN-based LEDs, and silicon (Si) is becoming its strong competitor d...