Growth, characterization and avalanche photodiode application of strain compensated InGaAsP/InAlAs superlattice

We applied InGaAsP/InAlAs strain compensated superlattice (SCSL) structure to the multiplication region of avalanche photodiode (APD) for the first time using gas-source molecular beam epitaxy. For the InGaAsP/InAlAs SCSL structure, material quality was evaluated by means of cross-sectional transmission electron microscope analysis and X-ray rocking curves. SCSL-APD device was fabricated and dark current property was also compared to normal InGaAsP/InAlAs superlattice avalanche photodiode (SL-APD). It was found that application of the SCSL structure to the multiplication layer in SL-APD improves the dark current property.