Monolithically integrated InGaAs/AlGaAs multiple quantum well photodetectors on 300 mm Si wafers
Résumé
Near infrared light detection is fundamental for sensing in various application fields. In this paper, we detail the properties of
InGaAs/AlGaAs multiple quantum well (MQW) photodetectors (PDs) monolithically integrated by direct epitaxy on 300 mm Si(001) substrates. A MQW high crystalline quality is achieved using 300 mm Ge/Si pseudo-substrates with a low threading dislocation density of
4 × 107 cm−2 from electron channeling contrast imaging measurements. The localized states in the MQW stack are investigated using
temperature-dependent photoluminescence. Two non-radiative recombination channels are identified. The first one is due to delocalized excitons generated by potential’s fluctuations because of the InGaAs/AlGaAs interfacial roughness (with an activation energy below
4 meV). The second one is due to exciton quenching because of the presence of numerous threading dislocations. A low dark current density of 2.5 × 10−5 A/cm2 is measured for PDs on Ge/Si substrates, i.e., a value very close to that of the same PDs grown directly on GaAs(001) substrates. A responsivity of 36 mA/W is otherwise measured for the photodiode on Ge/Si at room temperature and at −2 V.
Domaines
Physique [physics]| Origine | Fichiers éditeurs autorisés sur une archive ouverte |
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