Low-Frequency Noise in Semiconductor Optical Devices

Abstract

Low-frequency noise measurements were carried out on semiconductor optical devices in the frequency and temperature ranges from 10 Hz to 100 kHz and from 77 K to 300 K, respectively. The samples are mainly photocouplers which include light emitting diodes (LED) and photodiodes (PD). The noise spectra of LED are considered to be superpositions of generation-recombination (g-r) noise components caused bv traps, and the activation energies of these traps are determined from the temperature dependence of noise. We also calculated the current dependence of noise and the correlation coefficients of noise between LED and PD, and discussed the mechanism and relation of these noises.