Silicon-Germanium multi-quantum well photodetectors in the near infrared

Single crystal Silicon-Germanium multi-quantum well layers were epitaxially grown on silicon substrates. Very high quality films were achieved with high level of control utilizing recently developed MHAH epitaxial technique. MHAH growth technique facilitates the monolithic integration of photonic functionality such as modulators and photodetectors with low-cost silicon VLSI technology. Mesa structured p-i-n photodetectors were fabricated with low reverse leakage currents of ∼10 mA/cm² and responsivity values exceeding 0.1 A/W. Moreover, the spectral responsivity of fabricated detectors can be tuned by applied voltage.