Temperature dependent pulsed and ramped substrate bias measurements are used to develop a detailed understanding of the vertical carrier transport in the buffer layers in a carbon doped GaN power heterojunction field effect transistor. Carbon doped GaN and multiple layers of AlGaN alloy are used in these devices to deliver an insulating and strain relieved buffer with high breakdown voltage cap...

substitution of two or four carbon atoms by nitrogen in the corannulene molecule as a carbon nanostructure was done and the obtained structures were optimized at mp2/6-31g(d) level of theory. calculations of the nucleus-independent chemical shift (nics) were performed to analyze the aromaticity of the corannulene rings and its derivatives upon doping with n at b3lyp/6-31g(d) level of theory. re...

Magnesium (Mg) is the most commonly used acceptor dopant in gallium nitride (GaN) devices. Acting as a deep acceptor with an activation energy of ~ 200 meV, Mg can introduce electrical and optical complications. Carbon has been demonstrated to be a possible alternative acceptor dopant atom with a lower activation energy [1]. Carbon-doped GaN (GaN:C) samples were homoepitaxially grown on <10-11>...

p s s current topics in solid state physics c status solidi 1 Introduction AlGaN/GaN high electron mobility transistor (HEMT) technology is rapidly advancing into the 100-200 GHz operation regime with the scaling of gate length, and the reduction of parasitic elements. Scaling of vertical het-erostructure dimensions is needed to support further improvements in HEMT performance. Therefore, ultra...

in this work we report synthesis and magnetic characterization of cobalt doped zno nanoparticles (with different percent of doped cobalt oxide). synthesis of the materials was carried out at room temperature by polyacrylamide-gel method, using zink sulfate and cobalt nitrate as source materials, acrylamide as monomer and n,n-methylene bisacrylamide as a lattice reagent. characterization of the ...

We report flicker noise measurements combined with deep-level transient spectroscopy of the doped and undoped channel GaN/AlGaN heterostructure field-effect transistors. The lowtemperature noise spectra for the doped devices show clear generation-recombination peaks. The value of the activation energy extracted from these noise peaks is consistent with the activation energies measured using dee...

A comprehensive methodology to qualify the reliability of GaN products 2 Introduction The industry takes the reliability of silicon power transistors for granted due to over thirty years of experience and continuous improvement. This longstanding experience has resulted in a mature qualification methodology, whereby reliability and quality are certified by running standardized tests. These test...

P-type doping in high Al-content AlGaN alloys is a main challenge for realizing AlGaN-based deep ultraviolet optoelectronics devices. According to the first-principles calculations, Mg activation energy may be reduced so that a high hole concentration can be obtained by introducing nanoscale (AlN)5/(GaN)1 superlattice (SL) in Al0.83Ga0.17N disorder alloy. In this work, experimental evidences we...

This work focuses on investigations of the luminescence properties of coaxial InGaN layers around single GaN nano-tubes on top of GaN micro-pyramids. The nano-tube structure was formed after the controlled desorption of ZnO nano-pillar templates during the coaxial GaN epitaxy. An intense and broad photoluminescence (PL) peak centered around 2.85 eV is attributed to transitions from a shallow do...