[Photoelectron decay properties of doped AgCl microcrystals under chemical sensitization]

The photoelectron decay characteristic directly reflects the photographic efficiency of silver halide crystals. Measurement of the electronic decay time-resolved spectrum of silver halide microcrystals can provide important information about the photoelectron decay action in latent image formation process. In order to know the influence of shallow electron trap dopant K4 Fe (CN)6 and S+Au on photoelectron decay, the photoelectron decay time-resolved spectra of AgCl emulsion doped by K4 Fe(CN) and that doped by K4 Fe(CN) firstly and then sensitized by S+Au were detected by microwave absorption dielectric technique, which can be used to study the decay process of free photoelectrons and shallow-trapped electrons in semiconductor crystals. The experimental results show that when the doping content is 10(-8)-10(-7) mol x mol(-1) Ag, the photoelectron decay process becomes slower, namely, the photoelectron decay time is longer, as the doping is near the grain surface before sensitization. After S+Au sensitization, the photoelectron decay becomes faster, showing that the sensitization centre acts as a deep electron trap. And when the doping is near the grain surface with 90% Ag, the photoelectron decay time becomes shorter, showing that the doping centre and the sensitization centre may interact.