We report on the investigations of the fin-shaped GaN/AlGaN field effect transistors with two lateral Schottky barrier gates exactly placed on the edges of the fin-shaped transistor channel. This kind FinFET modification (EdgeFET) allowed us to efficiently control the current flow in two-dimensional electron gas conduction channel. We present experimental data of sub THz detection by EdgeFETs. We describe also how it is beneficial for observation of resonant plasma wave THz detection and emission.
We report on the investigations of the fin-shaped GaN/AlGaN field effect transistors (FinFETs) with two lateral Schottky barrier gates exactly placed at the edges of the fin-shaped transistor channel. This kind of FinFET modification (called EdgeFET) allowed us to efficiently control the current flow in two-dimensional electron gas conduction channel. Moreover, due to depletion, regions of the channel at a certain range of reverse bias form a nanowire, which is beneficial for the tunable resonant THz detection. Our studies of current-voltage characteristics and response in the sub-terahertz frequency range confirm the validity of the approach.
In the present work we demonstrate a concept of a "weak plasmonic cladding" for the improved transversal optical confinement in the
structures of nitride lasers diodes emitting in the violet and blue spectral region. We show that by using highly doped GaN:O or
GaN:Si layers we can induced the reduction of the refractive index by around 1-2% comparing to a lightly doped material. Such a
material can be effectively used as optical cladding replacing thick, highly strained AlGaN layers. Plasmonic claddings can be grown
by two methods: first of them is High Nitrogen Pressure Solution growth (an introduced donor is an oxygen) and Molecular Beam
Epitaxy with silicon as a donor. In the both cases we can reach a free carrier concentration of up to around 1020cm-3. MOVPE method
so far did not show capabilities for achieving so high doping level. We demonstrate the use of such layers for the construction of the
violet and blue laser diodes and laser diodes mini-arrays showing a total suppression of the substrate mode leakage.
We report on the 1.5 μm intersubband absorption measured on GaInN multi-quantum wells with AlInN barriers grown by RF plasma assisted molecular beam epitaxy (PAMBE). The intersubband light absorption was
demonstrated as a function of the well width (1.3 nm - 3 nm) at the wavelength 1.4μm - 2.5 μm. The use AlInN barriers allowed to achieve strain compensated and crack free structures on GaN substrates. The preformed XRD mapping of a and c lattice constants show that AlInN/GaInN MQWs are fully strained and have up to 7% of indium in the barriers. The replacement of AlGaN by AlInN barriers opens new possibility to grow strain compensated crack free intersubband based devices like electooptical modulators and switches operating at telecommunication wavelengths.