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We present a lamellar grating interferometer realized with microelectromechanical system technology. It is used as a time-scanning Fourier-transform spectrometer. The motion is carried out by an electrostatic comb drive actuator fabricated by silicon micro ...
UV detection is interesting for combustion optimization, air contamination control, fire and solar blind rocket launching detection. Most of these applications require that UV detectors have a huge dynamic response between UV and the visible, and a very lo ...
Resonant-cavity InGaN/GaN quantum well light emitting diodes have been fabricated. Nitride layers were grown by molecular beam epitaxy on Si (111). We fabricated the structures using a combination of Si substrate etching, GaN etching and dielectric (Ta2O5/ ...
A blue resonant cavity light emitting diode with a 50% Al-content crack-free GaN/AlGaN distributed Bragg reflector is reported. The structure shows excellent optical properties and the benefits of the cavity structure are clearly seen in the narrowed spect ...
Thin, single semi conducting layer of GaInN, possibly containing a small percentage of arsenic, phosphorus or antimony, the said layer emitting at least two visible lights with determined colours which can be combined, particularly to obtain white light. M ...
We present a study on the dependence of the external Quantum Efficiency (QE) of Light Emitting Diodes (LEDs) on the device properties and p-contact metallisation. The external QE could be doubled by changing the p-type contact from oxidised Ni/Au to non-an ...
A device includes a silicon substrate provided with a coating including at least one stacking constituted by a plane of GaN or GaInN quantum dots emitting visible light at room temperature in a respective layer of AIN or GaN. The method of making the devic ...
Multicolor, multi-quantum well light emitting diodes have been fabricated by molecular beam epitaxy by inserting quantum wells of various widths in the active region. The In content of the wells is 15%-20% and the color is governed by carrier confinement a ...
The use of photonic crystals (PCs) for realistic light emitting diodes (LEDs) is discussed, given the constraints of planar semiconductor technology. A viable route for the fabrication of high-efficiency high-brightness electrically injected LEDs is presen ...
We have measured the temperature dependence of the mobility of the two-dimensional electron gas in AlGaN/GaN heterostructures grown on bulk GaN substrates. The linear dependence of the inverse mobility on temperature at temperatures below 50 K indicates th ...