Hydrogen equilibration in polycrystalline silicon

Hydrogen equilibration in polycrystalline silicon was investigated as a function of annealing time and temperature using electron spin resonance and hydrogen effusion measurements. During a vacuum anneal at least 1.5x10(21) cm(-3) H atoms are mobile in the lattice, however, only about 3.7x10(18) cm(-3) H atoms passivate Si dangling bonds. The results show that the annealing treatment can cause the vast majority of H atoms to accumulate in H stabilized platelets. Since defect passivation preferentially occurs at grain boundaries and platelet nucleation and growth are confined to the interior of single-crystal grains, H equilibration is governed by two spatially separated processes. Moreover, the data demonstrate that the hydrogen density-of-states distribution is dynamic and changes in response to experimental parameters. (c) 2007 American Institute of Physics.