Mcrostructure And Optical Properties Of Ge(Si) Dots Grown On Si

The microstructural, luminescence properties and photoresponse of multi-layer Ge(Si) quantum dots grown on Si (100) substrates are studied. The strain and composition of the dots are studied by synchrotron-radiation x-ray. The dots are found to be Si0.58Ge0.42 alloy with 50% strain relaxed in average. The photoluminescence from the dots is obseved up to room temperature. The thermal stability of the quantum dots is studied. P-i-n structures are grown with Ge(Si) dots embedded in the i-layer for photodetection investigation. The photoresponse wavelength of Ge(Si) dots covers the wavelength range of 1.3-1.52 mum and relatively high external quantum efficiency is obtained.