Anodic electrodeposition of ZnO onto p-Si substrates assisted by light irradiation
Résumé
ZnO was electrodeposited on p-type silicon substrates with the assistance of light irradiation in order to allow the presence of electrons at the interface of the semiconductor/ electrolyte. The electrodeposition was performed at -0.9 V versus Standard Hydrogen Electrode (SHE). Scanning electron analysis revealed that the ZnO deposit consisted of small islands of ZnO randomly dispersed on the p-Si surface. The small islands are in the order of the micron size, and cover *37% of the whole surface after 4 min of deposition. The characteristic E2 vibration mode in the Raman spectroscopy was clearly observed from the asdeposit ZnO. Photoluminescence measurements of the deposit reveal that the near band edge emission of ZnO is *12 times more intense than the defects emission band around 543 nm, which is attributed to the presence of interstitial oxygen, and may come from the electrodeposition process in an oxygen rich medium.