Coherent Ge quantum dots embedded in Si spacing layers were grown on Si substrate by molecular-beam epitaxy in the Stranski-Krastanov mode. Photoluminescence measurement showed a Ge-dot-related peak at 1.46 μm. p-i-n photodiodes with the intrinsic layer containing Ge dots were fabricated, and current-voltage (I-V) measurement showed a low dark current density of 3×10-5A/cm2 at -1 V. A strong photoresponse at 1.3-1.52 μm originating from Ge dots was observed, and at normal incidence, an external quantum efficiency of 8% was achieved at -2.5 V.
All Science Journal Classification (ASJC) codes
- Physics and Astronomy (miscellaneous)