Photoelectromagnetic effect in amorphous silicon

The short-circuit current and open-circuit voltage of the photoelectromagnetic effect have been measured at room temperature in discharge-produced amorphous hydrogenated silicon (undoped, n type). From the magnitude and spectral distribution of the effect, the minority (hole) diffusion length and the hole μτ product are estimated to be 0.09 μm and 3×10−9 cm2/v, respectively, while the electron mobility is 5×10−2 cm2/v sec. From the photoconductivity the electron μτ product (majority carrier) was 8×10−8 cm2/v. Derived quantities are then hole mobility 9×10−3 cm2/v sec, hole lifetime 3×10−7 sec, electron lifetime 1.7×10−6 sec. The sign of the effect is normal. It does not show the inverted sign reported for the Hall effect in the dark.