Persistent photoconductivity and field-enhanced conductivity in amorphous-silicon doping-modulated superlattices

We have found both a large persistent photoconductivity and a remarkable field-enhanced conductivity (FEC) showing a three-orders-of-magnitude enhancement after application of low electric fields (20–100 V${\mathrm{?}}^{\mathrm{-}1}$) in nipnip. . . doping-modulated superlattices of amorphous hydrogenated silicon. The structures are up to ten times wider (1 cm) than previous structures. The dependence of the FEC on field and temperature shows it is caused by a relatively limited number of trap states.