Effect of substrate temperature on the thermal stability of Cu/Zr–N/Si contact system

Abstract

The effect of substrate temperature on the thermal stability of Cu/Zr–N/Si contact systems was investigated. Zr–N films were deposited on the Si substrates by RF reactive magnetron sputtering under various substrate temperatures. Cu films were in-situ sputtered onto the Zr–N films subsequently. The contact systems were characterized using four-point probe sheet resistance measurements (Rs), X-ray diffraction (XRD), and scanning electron microscopy (SEM) respectively. It was found that the sheet resistances of Cu/Zr–N (350 °C)/Si contact system were lower than those of Cu/Zr–N (150 °C)/Si specimens after annealing at 650 °C. Cu/Zr–N (350 °C)/Si contact systems showed better thermal stability so that the Cu3Si phase could not be detected. It is indicated from the comparison analysis results that the Zr–N film showed better diffusion barrier performance deposited under higher substrate temperature.