Low Resistivity Hafnium Nitride Thin Films Deposited by Inductively Coupled Plasma Assisted Magnetron Sputtering in Microelectronics.

Abstract

Hafnium nitride (HfN) thin films with low electrical resistivity were obtained by inductively coupled plasma assisted magnetron sputtering as a function of ICP power. Microstructural, crystallographic and sheet resistance characterizations of HfN films were performed by field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), X-ray diffraction (XRD) and 4 point probe method. The results show that ICP has significant effects on coating's microstructure, structural and electrical properties of HfN films. With an increase in ICP power, thin film microstructure evolved from a porous columnar structure to a highly dense one. HfN thin films with different crystal structure and phases were obtained as a function of ICP power. The minimum resistivity of 125 µΩ-cm, the smoothest surface morphology with Ra roughness of 5.9 nm were obtained for the HfN films deposited at ICP power of 200 W.