Non-radiative distant pair recombination in amorphous silicon

Luminescence decay in hydrogenated amorphous silicon and silicon nanostructures

“…The t I L (t) spectrum calculated from the luminescence decay is consistent with the QFRS life time spectrum with the two peaks in refs. [5] and [6] and the life times obtained are almost coincident. The t I L (t) spectra at E L = 1.10 eV in Fig.…”

“…The result of the quadrature frequency-resolved spectroscopy (QFRS) supports the existence of the fast and slow luminescence with these life times near LHeT [5,6]. Furthermore, the luminescence with the life times from 1 μs to 10 s due to the radiative tunneling recombination of the distant electron-hole pairs, which is distinguished from the fast and slow luminescence components, is found in the QFRS [6].…”

Coexistence of geminate and non-geminate recombination in a-Si:H and a-Ge:H observed by quadrature frequency resolved spectroscopy

“…A double-peaked lifetime distribution of PL consisting of the short-lived ($ls) and long-lived ($ms) components obtained by the QFRS, suggests the exciton recombination in a-Si:H [1] and a-Ge:H [2] at low temperatures T ; the short-and longlived components involve singlet and triplet excitons, respectively, under the geminate recombination condition for generation rate G 6 10 19 cm À3 s À1 . We further confirmed, by extending the QFRS to ns region, that no peak exists around ns in the lifetime distribution, and estimated the singlet-triplet exchange energy to be $40 meV for aSi:H from the PL spectra of the two components [3,4].…”

Understanding the photoluminescence over 13-decade lifetime distribution in a-Si:H

“…It is difficult to identify the two lifetime components on the basis of the RT model [9,10]. Stachowitz et al [11] proposed exciton involvement in the double peak phenomena, attributing the short-and long-lived components to singlet and triplet excitons, respectively. We observed double-peak lifetime behavior not only in a-Ge:H but also chalcogenide amorphous semiconductors (e.g., g-As 2 S 3 and a-Se), which supports the exciton model [12,13].…”