Thermally stable ZrN/Zr₃N₄bilayered barrier system for through-Si-via process

We propose the use of a system composed of successively deposited ZrN (diffusion barrier)/Zr 3 N 4 (insulating layer) barrier layers with the same constituents in the via-last through-Si-via (TSV) process. A preliminary examination of low-temperature-deposited Zr 3 N 4 films by reactive sputtering reveals that the films show good characteristics as an insulating layer comparable to those of SiN x films prepared at low temperatures. The TSV model system of Cu/ZrN/Zr 3 N 4 /Si tolerates annealing at 500 °C for 60 min without any change in structure and/or configuration, showing good thermal stability as a candidate TSV barrier system.