Determination of the electric field distribution within multi-quantum-well light emitting diodes by the use of electron beam induced methods

Dynamic electron beam induced methods are applied to determine the local electrical field distribution of devices with small depletion regions. The dissipation volume generated by the electron beam is much larger than the depletion region during these investigations. The frequency behavior of the electron beam induced signal must be analyzed in order to determine the field strength accurately. The characteristics of the in-phase and quadrature components are discussed for lock-in detection in the frequency domain. Additionally, change of the collection efficiency due to the depletion region widening effect at different biasing conditions has to be taken into account. The advantage and possibility of this technique are demonstrated exemplarily for a commercial multi-quantum-well light emitting diode.