Chemical-mechanical polishing as an enabling technology for giant magnetoresistance devices

Abstract

Giant magnetoresistance (GMR) devices, integrated with conventional Si interconnects (ICs), are promising candidates for future data-storage applications. Chemical-mechanical polishing (CMP), a surface smoothing and planarization process, is anticipated to be a key technology in the demonstration of full functionality of such GMR components. In this work, we report on the fabrication of GMR device elements through chemical-mechanical polishing of silicon nitride interlevel dielectrics (ILD). Our results show that the silicon nitride polishing process using commercially available slurries and pads is compatible with copper interconnects and copper metallized GMR elements. Contact resistivity between Cu and Cu as low as 5×10 −10 Ω-cm 2 has been achieved with the CMP process and related processing techniques, as obtained by de-embedding the contact resistance from GMR device measurements.