Time resolved spectroscopy of mid-band-gap emissions in Si-doped GaN

Abstract

Silicon is until now the most promising dopant for n-type GaN. Besides the near-band-gap emission centred at 3.461eV, which becomes broader with increasing Si concentration also transitions at lower energies are observed. These emissions decrease strongly when the silicon concentration increases. While the near-band-gap emission is due to fast transitions (with decays shorter than 10μs) the lower energy emissions have longer components whose behaviour is discussed.