Oliver Ambacher

TL;DR: In this paper, the growth of nominally undoped GaN/AlxGa1−xN/GaN (x < 0.4) high mobility heterostructures with N-face or Ga-face polarity on sapphire substrates by plasma-induced molecular beam epitaxy (PIMBE) and metalorganic chemical vapor deposition was studied.

TL;DR: In this paper, a method of separating two layers of material from one another in such a way that the two separated layers are essentially fully preserved is proposed. But the method is not suitable for the case where the electromagnetic radiation is absorbed at the interface or in the region in the vicinity of the interface and the absorbed radiation energy induces a decomposition of material at the interfaces.

TL;DR: In this paper, the authors present theoretical and experimental results demonstrating how polarization induced electric fields and bound interface charges in group-III nitrides can lead to the formation of two-dimensional carrier gases suitable for the fabrication of high power microwave frequency transistors.

TL;DR: In this paper, the piezoresistive effect in piezoelectric AlGaN layers is investigated and the dependence of the gauge factor on the Al content is attributed to the influence of strain induced piezOElectric fields.

TL;DR: In this article, the performance of a number of relevant exhaust gas components (H 2, HC, CO, NO) was tested with the test gas concentrations and the composition of background gases were chosen to simulate exhaust gas emissions from lean-burn engines.