A DETAIL ANALYSIS OF ELECTRICAL AND OPTICAL FLUCTUATIONS OF GREEN LIGHT-EMITTING DIODES BY CORRELATION METHOD
A detail analysis of electrical and optical fluctuations of large power (1 W) green light-emitting diodes (LEDs) is presented. Special attention was directed to measurement and interpretation of correlation coefficient between electrical and optical fluctuations. The correlation coefficient was measured not only over frequency range from 10 Hz to 20 kHz, but also in every one-octave frequency band by using digital filters. It is shown that correlated part of electrical and optical fluctuations for investigated green LEDs is related with random potential fluctuations of parameters of quantum well due to charge carrier capture by the defects in the active layer, while uncorrelated part of electrical noise is caused by parallel leakage channel which resistance is many times higher than that of p-n junction.