High-quality Cr-doped InGaAs/InP(100) MQWs grown by tert-butylarsine in a MOVPE apparatus

We have studied the introduction of deep levels in InGaAs/InP multi quantum wells (MQW) grown by metal organic vapour phase epitaxy (MOVPE) using tert-butylarsine (tBuAsH2) as arsenic precursor as well as chromium (bis-cyclopentadienyl chromium) and zinc (dietyl-zinc) as dopant elements able to promote recombination centres in the ternary alloy. We have utilized secondary-ion mass spectrometry to measure dopant concentrations and high-resolution X-ray diffraction (HRXRD) for structural characterization. Particularly for the chromium-doped systems, frequency- and time-resolved optical spectroscopy of the MWQ ground-state transition confirms an increase of the carrier recombination rate upon an increase of defect density, while the electronic and structural properties of the sample are largely preserved.