Comparative Study of n-Type 4H-SiC: Raman vs Photoluminescence Spectroscopy
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We study the influence of the growth conditions on the residual strain and related optical and structural properties in the case of 3C-SiC films grown on (001) silicon substrates. We show that two possible mechanisms compete to manage the final sample bow: one is by controlling the composition of the gaseous phase (C/Si ratio) the other one by...
Investigation of Aluminum Incorporation in 4H-SiC Epitaxial Layers
Raman Investigation of Heavily Al Doped 4H-SiC Layers Grown by CVD
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Influence of Growth Temperature on Site Competition Effects During Chemical Vapor Deposition of 4H-SiC Layers
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Photoluminescence study of Mg-doped GaN and AlxGa1-xN (x<0.4) grown by molecular epitaxy
Piezoelectric effects on the optical properties of GaN/AlN quantum dots have been investigated by both continuous-wave and time-resolved photoluminescence (TRPL) measurements. The increase in excitation density in CW-PL leads to a blue shift of the transition energy. The TRPL measurements reveal a very large blue-shift (0.6 eV) of the PL peak...
Effect of Temperature on Electrical Transport Properties of MBE grown Mg-doped GaN and AlGaN
We analyze the low temperature photoluminescence properties of two multi-layer stacking of GaN/AlN quantum dots. We report drastic differences of linewidths between continuous wave and time-resolved photoluminescence experiments. After the pulsed excitation, time-resolved photoluminescence reveals a substantial red shift of the line, which...
In the case of molecular beam epitaxy (MBE), the Mg acceptors are electrically active in the as‐grown material and a priori no additional annealing procedure is necessary. However, there are still some peculiarities in the electrical properties of ammonia‐process grown GaN:Mg and some annealing effect can be observed. Additionally, the...
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Abstract Ultrawide bandgap (UWBG) semiconductors offer new possibilities to develop power electronics. High voltage operation for the off‐state as well as high temperature stability of the devices in on‐state are required. More than AlGaN/GaN heterostructures, AlGaN/AlGaN heterostructures are promising candidates to meet these criteria....