CHENOT , S.

In this work, a series of AlGaN/GaN high electron mobility transistors (HEMTs) have been grown on patterned (Al)GaN-on-Si seed layers by metalorganic chemical vapor deposition (MOCVD) to study the effect of the (Al)GaN buffer thickness and its aluminum content on the vertical breakdown voltage. The atomic force microscopy (AFM) analysis...

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We report magnetotransport measurements performed on AlGaN/GaN devices with different buffer layers. Standard samples with a 1 μm thick GaN buffer show a linear Hall resistance and an almost constant magnetoresistance, as expected from a single two-dimensional electron gas (2DEG) at the AlGaN/GaN interface. Other samples, with an Al x Ga1– x N...

International audience

International audience

We present capacitance-voltage [C(V)] measurements of self-assembled wurtzite-GaN quantum dots (QDs). The QDs are embedded in a charge-tunable diode structure and were grown by molecular beam epitaxy in the Stranski-Krastanov growth method. The internal electric fields present in GaN and its alloys together with its wide bandgap make this...

The use of tunnel junctions (TJs) is a potential solution in blue LEDs to poor p-contacts, replacing it by another n-contact. TJs are even more advantageous for UV emitting structures, which suffer from the considerably low injection efficiency in high Al concentration UV LEDs. In this work we report our work on Ge n-doped GaN and AlGaN TJs...

Any arbitrary state of polarization of a light beam can be decomposed into a linear superposition of two orthogonal direction of the oscillations, each of which has a specific amplitude of the electric field. The dispersive nature of diffractive and refractive optical components generally affects these amplitudes significantly over a small...

AlGaN based light emitting diodes (LEDs) will play a key role for the development of applications in the ultra-violet (UV). In the UVB region (280–320 nm), phototherapy and plant lighting are among the targeted uses. However, UVB LED performances still need to be improved to reach commercial markets. In particular, the design and the...

Due to giant built-in electric fields excitons in wide GaN/(Al,Ga)N quantum wells (QWs) are spatially indirect iven in the abscence of any external electric bias and posess microsecond lifetimes, large dipole moment in growth direction, and tens of microns diffusion lengths [Fedichkin2016]. This make them potentially interesting for excitonic...