Time-resolved photoluminescence spectra in sputtereda-Si:H

We report measurements of the time-resolved photoluminescence spectra of sputtered $a$-Si:H. The dependence of $E_p$, the peak energy of the luminescence spectrum, on time for 10 ns $t<\mathrm{}0.1\mathrm{}$ ms, is discussed for samples produced under different conditions and characterized by other property measurements. A feature in $E_p\mathrm{}\left(t\right)\mathrm{}$ for 10 ns $t$$\mu s$ is observed and attributed to an electron-hole Coulomb contribution. The excitation energy dependence of $E_p\mathrm{}\left(t\right)\mathrm{}$ is also measured and discussed.