Phonon-assisted nonradiative energy transfer from colloidal quantum dots to monocrystalline bulk silicon

In this work, we used bulk monocrystalline p-type Si (100) substrate as the acceptor and core/shell CdSe/ZnS QDs as the donor. To match the absorption spectrum of silicon, QD peak emission wavelength was set to 580 nm. Our Si substrates possessed approximately 1.65 nm thick native oxide on the top, as verified by the ellipsometry measurement. We deposited Al2O3 thin film on pre-cleaned Si substrates as a dielectric spacer using atomic layer deposition(ALD) technique.