LED Characterization Station

Electroluminescence (EL) by definition is the illumination from the material under the passage of an external voltage bias (electrical field) or injection current. This phenomenon is ‚Äčthe result of radiative recombination in a material. In the direct bandgap semiconductor, the excess electrons and holes flow into the semiconductor, recombine and release their energy as photons without changing the crystal momentum. The photons are emitted as output light in the LEDs. The intensity of the output light is then collected by spectrometer under various injection currents. At the same time, the device electrical properties are also investigated, such as current versus voltage (I-V), and output light power versus current injection (L-I). In these characterizations, we can understand the device physics and carrier recombination mechanism in our membrane LED. The experiment setup in KAUST Photonics Lab is as below.

I-V, L-I and EL setup: Keithley 2400 source meter, Newport 2936C power meter and Ocean Optics QE65000 spectrometer.