p -Type NiO thin films obtained via an electrochemical-thermal route

The development of procedures for the synthesis of p -type NiO on top of non-degenerate semiconductors is of great interest due to the potential applications in several areas of microelectronics. In this work, p -type NiO films with different resistivity values are obtained by heating at different temperatures Ni(OH) 2 layers electrodeposited on n -type monocrystalline Si substrates. Characterizations by X-ray diffraction and X-ray photoelectron spectroscopy have evidenced the phase change, from hexagonal β-Ni(OH) 2 to cubic NiO for all treated samples, with improved crystallinity for higher heating temperatures. The effect of the electrochemical parameters and heat treatment temperatures on the thickness and surface morphology of the films was also analyzed by mechanical profilometry and scanning electron microscopy, respectively. The p -type behavior of the films and the electrical resistivity values were determined from electrical measurements using a two-point probe system in a sandwich configuration. Higher resistivity values were found for films subjected to higher heat treatment temperatures.