Published online by Cambridge University Press: 10 February 2011
Two-pulse-echo field-sweep spectra of boron-doped samples show in addition to dangling bonds (DB) a very broad feature of approximately 500 G width. This feature is the sum of several lines whose relative intensities change with doping and temperature. The total intensity increases with doping. The spin-lattice relaxation time TI of the resonance at g=1.998 referred to as conduction electrons (CE) has been studied for undoped and P-doped microcrystalline silicon. The discrepancy between T1 values previously reported has been resolved and the values for CE are at least two orders of magnitude smaller than those of the DB. In undoped samples cross-relaxation between the CE and DB spin systems might explain the similar T1 values obtained for CE and DB in inversion recovery measurements.