Enhanced bandgap blue-shift in InGaAsP multiple-quantum-well laser structures by low-temperature-grown InP

Quantum well intermixing (QWI) in an InGaAsP multiple-quantnm-well (MQW) la ser structure is demonstrated using an InP epitaxial layer grown at 300 deg reesC, by gas source molecular beam epitaxy, followed by rapid thermal anne aling. Photoluminescence is used to compare the magnitude of the QWI proces s between low-temperature (LT)- and normal-temperature (NT, 470 degreesC)-g rown InP layers as a function of both anneal temperature and time, For exam ple, after an anneal at 780 degreesC, a large bandgap blue-shift of similar to 197 nm is observed in MQW structures capped with LT-InP as compared to an similar to 35 nm shift in identical structures capped with NT-InP, Also, the effect of the LT-InP capping is compared to NT-InP, capped with a diel ectric (similar to 100 nm of SiO2), following anneal at 800 degreesC for 60 s. This shows blue-shifts of similar to 243 and similar to 142 nm, respect ively.