Ge nanodots embedded in a silica matrix
نویسندگان
چکیده
The properties of GeSiO films consisting of Ge nanodots embedded in SiO2 matrix, prepared by sol-gel and magnetron sputtering methods, followed by an adequate thermal annealing, are studied and discussed in this paper. Structural investigations were performed by means of transmission electron microscopy and Xray photoelectron spectroscopy. In the sol-gel films one finds amorphous Ge nanodots distributed in the amorphous matrix, while in the sputtered ones tetragonal Ge nanodots are evidenced. The electrical and photoconductive properties of sol-gel films treated by rapid thermal annealing technique were also studied. For this, measurements of current-voltage and conductance-temperature curves, spectral and bias dependences of the photocurrent were carried out. These films have weak rectifying behaviour and show a very high photoconductivity.
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