ROLE OF DANGLING BOND CENTERS ON RADIATIVE RECOMBINATION PROCESSES INPOROUS SILICON

The role of Si dangling bonds (P-b center) on the bread luminescence b and around 1.1 eV of porous Si is discussed, based on transient wave f orm measurement of optically detected magnetic resonance. The observed wave form is compatible with the nongeminate shunt path scheme and th e characteristic time constant of this nonradiative process is deduced to be 15 mu s at 1.6 K, whereas the competing radiative channel has a shorter decay time of 3 mu s. Therefore, P-b centers are unlikely to be involved as a radiative state in this infrared luminescence. Result s are also discussed in conjunction with the visible luminescence proc ess. (C) 1995 American Institute of Physics.