An optimized ZnO:Al/a-pin SixC1-x:H/Al configuration for the laser scanned
photodiode (LSP) imaging detector is proposed. The LSP utilizes self-field-
induced depletion layers as detector and a laser beam for readout. The effe
ct of the sensing element structure, cell configuration and light source fl
ux are investigated and correlated with the sensor output characteristics.
Experimental data reveal that the large optical gap and the low conductivit
y of the doped a-SixC1-x:H layers are responsible for an induced inversion
layer at the illuminated interfaces which blocks the carrier collection. Th
ese insulator-like: layers act as MIS gates that prevent excess signal char
ge from spreading to the nearby dark regions, which would lead to image sme
aring. The physical background of the LSP is discussed.