An electron spin resonance study of Si1−xGex alloy nanocrystals embedded in SiO2 matrices—effects of P doping

Electronic Structure of 1 to 2 nm Diameter Silicon Core/Shell Nanocrystals: Surface Chemistry, Optical Spectra, Charge Transfer, and Doping

“…The intensity of these transitions should decrease with increasing distance between donor and acceptor. This result is generally consistent with the prior proposal in luminescence studies that the P electron will transfer to, and pair with, the radical extra electron. − …”

“…There is an interesting experimental connection between luminescence, dangling bonds, and doping. − The effect of P doping has been studied in oxide films containing oxide passivated Si (also SiGe alloy) nanocrystals emitting near 1.4 eV on their band gap transitions. Luminescence increases, and the ESR dangling bond signal decreases, as P content initially increases.…”

“…This result is generally consistent with the prior proposal in luminescence studies that the P electron will transfer to, and pair with, the radical extra electron. [49][50][51][52][53][54] The ionization potential of the PH donor nanocrystal Si 65 H 64 -(Psurf) is 3.79 eVsquite lowsbut still higher than the electron affinity of the radical nanocrystal 3.09 eV. In a vacuum when the nanocrystals are at infinite separation, transfer is endothermic.…”