Temperature dependence of low-frequency electrical noise and reliability of semiconductor lasers

Abstract

Measurements of low-frequency electrical noise (LFN) in quantum-well (QW) semiconductor lasers have been conducted using index guided AlGaInP lasers. To investigate location and origin of the LFN in QW lasers, temperature dependence of the LFN is investigated over a wide range of injected current from 10-7 to 6 X 10-2 A, at temperatures between 0 degree(s)C and 65 degree(s)C. The effects of a short duration of burn-in process on the LFN have been investigated by measuring the LFN in the virginal device and the device after 20 hours stress (current I equals 45 mA, temperature T equals 40 degree(s)C). We find, (1) there are different noise mechanisms associated to the observed terminal current noise when laser diodes operate above and below threshold current; (2) it is much more clear to see the effects of the stress on the LFN versus injected current (SI - ID) than in current versus voltage (ID - V) and optical-power versus injected current (PO - ID); (3) over the wide range of injected current, we did not observe the temperature dependence of the 1/f, though different g-r components appear in the spectra of the LFN measured at different temperatures. We have qualitatively analyzed the noise mechanisms and their location. We will also demonstrate that the noise measurement can be used as a diagnostic tool for the reliability of QW laser diodes.