Spectral features of the photoresponse of structures with silicon nanoparticles

The spectral characteristics of the photoresponse of heterostructures with layers of densely packed amorphous silicon nanoparticles produced by laser electrodispersion are studied. The structures exhibit rectifying properties. Annealing in air results in the appearance of silicon oxide nanoparticles in the layers and, in addition, there occurs partial crystallization of the nanoparticles. The spectral characteristics of the photoresponse of the heterostructures have a number of specific features. Compared with standard silicon photodiodes, the sensitivity spectra of the structures under study are shifted to shorter wavelengths, with the shift becoming more pronounced upon annealing. The structures with an annealed layer of nanoparticles exhibit sensitivity in the spectral range 350–600 nm, which exceeds by more than an order of magnitude the sensitivity of unannealed structures. This effect can be attributed to a transistor-like effect in the structure.