Low-temperature scanning tunneling microscope-induced luminescence of an InGaN/GaN multiquantum well

We report the scanning tunneling microscope-induced luminescence of an InGa N/GaN multiquantum well. Spectral analysis confirms the dominance of quantu m well luminescence. This dominance is discussed in terms of the extent of band bending near the surface. The onset of light emission occurs at a bias larger than the emitted photon energy. This observation agrees with a tunn eling in the GaN cap prior to a transport to the quantum well. Luminescence images exhibit features 30-100 nm in size and are discussed in relation to previous studies. (C) 1999 American Institute of Physics. [S0003-6951(99)0 2510-3].