p-Type Cuprous Oxide Thin Films Electrodeposited on Si Nanowires with (100) Orientation

The n- type silicon nanowires with vertically aligned different lengths and diameters were produced from the commercial n-type silicon wafers with (100) rientation using the metal assisted chemical etching method. Then, in order to fabricate p-type cuprous oxide/n-type silicon nanowire heterojunctions, the p-type cuprous oxide thin films were electrodeposited on the produced n-silicon nanowires. The X-ray diffraction patterns revealed that both the n-type silicon nanowires and p-type cuprous oxide/n-type silicon nanowire heterojunctions have cubic structure with a single phase. The cross-section field emission scanning electron microscopy images clearly showed the formation of the nanowires that have different lengths and diameters changing with the etching time. The optical characterizations by ultraviolet-visible-near infrared region spectrometry indicated that the reflectivity values of silicon nanowires and p-cuprous oxide/n-type silicon nanowire heterojunctions are much lower that of n-type silicon wafer. In addition, the diode performances of the heterojunctions were determined by current-voltage measurements and their ideality factors were found to be changed considerably depending on the structure of nanowires.